Boss RT-20 Rotary Speaker Simulator

As with most digital doo-dads, the tweakability is enormous. Plenty of tonal variations---read the manual!

I'm using this for guitar, on a pedalboard, after the wah and before the OD/distortion and delay pedals. No effects looping, just straight into the input of a Fender or Marshall amp. I tried moving it (the RT-20) down the effects chain, but I found it tended to compress the OD/distortion in an uncomplementary way. It's very quiet, but be careful with the built-in distortion. It wicks up the volume considerably (this can be compensated for with the blend control). The Leslie tones are delightful (even in non-stereo mode) and the Univibe is nice, too---although it's difficult to balance the intensity and speed effectively.

Jeez, it's built like the proverbial brick **** house.

No need . . . yet.

What a great pedal! It does exactly what I'd hoped for . . . it gets that big, fat Leslie sound without having to carry a 120-pound piece of furniture. The Univibe sounds right on the money, too. Just add a shade of the built-in distortion and channel Jimi or Robin. Bear in mind, this thing will not physically throw the sound around the room like a real Leslie, but logistically, it'll spare your back and get that tone---and EVERYBODY will comment on the super-groovy spinning lightshow it puts on (but don't use it drunk, it'll make you barf).

Just an update to my review of the RT-20 below

I moved the RT-20 from the stereo configuration into the front end of my amps to the parallel effects loop of one amp in my rig. I liked the stereo effect, but found it difficult to control my overall sound. With the effct in the paralell loop I found the rotary effect was not pronounced enough. I added an EQ in front of the RT-20. After some experimenting with the EQ frequencies, I found that a boost at 400 and 1600 HZ (the rest flat) brought the RT-20 to life in the parallel loop. These 2 frequencies sit on either side of the horn / rotor crossover which better matches the guitar to the leslie effect IMO. It has taken some time to integrate this effect into my rig however I now have my original sound, plus an excellent Leslie effect enhanced for guitar. What I mean by this is you can voice your notes to sit on the horn (treble) side or the rotor(bass) or in the middle. (Magic Carpet ride organ solo) Playing the effect by timing the fast and slow speeds relative to the tune you are playing adds, a lively color that accentuates your music as only a leslie can.
This review is not meant to say the RT-20 is difficult to work with. It is another tool in the arsenal, just took some moving around to dovetail it into the sound I am looking for.I hope the EQ discovery might help out someone else, might work in front of the amp as well however I have not tried this.

Simple controls, detented midpoints give good starting points for dialing in the correct sound. Display shows mode and rotating speed.

I'm running a Hammond Porta-B into the RT-20. The stereo output then runs to my stereo keyboard mixer/amp, and also to the main board for house sound. The key to getting a great sound is to have a really good ear and then tweak each of the settings to find it's sweet spot. I've got it set to mimic my leslie 145. If you listen closely in a quiet room, you can tell it's a simulator. In a band situation, it sounds exactly like a miked leslie. I've been playing Hammonds since the 1970's, and worked for a Hammond Dealer setting up new B-3's, so I've got a pretty good idea of what the proper sound is.

Built like the proverbial Mack Truck

Haven't had to use it.

If you are a Hammond player and looking to downsize your rig for practice, or open mic nights, etc. I'd strongly suggest you take a look. On a Hammond console you'll need to add a 1/4 inch output or make an adapter cable. On the Porta-B and all clones you'll already have the 1/4 line out. The only thing that keeps me from giving it a 10 is the overdrive. Try as I might, I just can't find a setting that really sounds like an overdriven 122 or 147.

The unit is relatively easy to get operational. Plug and play. Out of the box all the knobs set to 12:00 position, distortion off. plugged into amp input, First reaction was this sweet 3D chorus like sound, then hit the switch for the higher speed and it ramped up like a leslie. Sound is useful at the 12:00 tremolo speed, ramped back down and you could here the inertial lag of the rotor. Perfect. The manual is terse, explains the function of all controls and connections with supporting graphics. The manual explains the difference between the guitar and keyboard settings. I would have liked some additional verbage regarding the stereo operation.

85 strat, 85 Lado solo 2, 71 ES330 ---> A ---> FL9 ---- DC30
B ---> Chieftain --- RT-20(parallel FX loop)

All of the following was performed with RT-20 into the front end of the amps
First thing I did was set the brake on the RT-20 and adjusted the effect and direct levels by alternating between dry and effect , to balance the dry / effect level ( Mode 1). There is definitely some tone coloration, which I expected from the effect. BTW You can adjust the tone of the pedal by adjusting the horn balance knob even while braked. (an observation) When you switch between the various modes the RT-20 begins to spin at chorale speed even though you were in brake mode.I eventually settled in (around 9 - 10 o'clock for both the effect and direct pots). Then verified unity volume by alternating between effect bypass, chorale and Tremolo speeds tweaking till the bypass and effect were closely matched. (another observation) I noticed a brief signal aberation when switching from bypass to effect on which is annoying. Effect to bypass is clean though. I plan to AB switch the effect out of the signal chain anyhow so I'll deal with it. The pedal is not noisy however with the pedal engaged and with a very low input signal, there is some digital artifacts audible as the signal decays. This is not apparent if you strum a chord and let it decay, more apparent with just a low input signal, like it's below the threhold of a compressor or expander. I can live with that :-)

Now for the fun, I personally like the sound of the bass rotor acceleration and deceleration. To me this is the heart of a leslie, I listen to Bryan Lee's keyboard player, Mark, Lucky Peterson, John Lord the iconic Zep "since i've been loving you" etc. The way these guys toggle the leslie, select the draw bar voicings and chords to use the crossover 'hole' to select the rotor and horn is the nuance I am looking for, and is how I plan to operate the pedal. The Boss engineers have done a fabulous job of modeling the inertial effects of the bass rotor and horn. To a lesser degree the phasing relationship is in there as well. I have adjusted the horn / rotor balance to around 10 O'clock to give more emphasis to the rotor. I adjusted the ramp speed to around the 10 O'clock, high speed at 12. Flexibility of speed and ramp adjustments is a deciding factor for me. The slower ramp time gives more wump wump during acceleration and deceleration. Think "magic carpet ride". The horn / rotor speed relationships are truly random whem toggling the speed footswitch, exactly like a real leslie. This effect is NOT a slow /fast speed syrupy chorus pedal.

After playing for a few hours, I have actually adjusted my playing style and chord voicings to enable me to play the effect. This means constantly tapping between Chorale (slow) and tremolo (fast) as I play. Not going to find constant speed, vibratone "Cold Shot" here, this pedal does much more. The boss style footswitch is perfect for this repetetive switching.It's not a 147 or 122 with the combo preamp, which I have played through, but it is damn close.

Moving forward I tried a couple of pedals in front of the RT-20. It's a little touchy due to the crossover but you can dial in some decent sounds, An Ibanez CP9 made the horn to bright, The TS9 is on the edge but much better than the onboard distortion for guitar, the Boss CE-5 caused a volume drop when engaged. I connected it in stereo as the manual eludes to. Not sure if there is some kind of a phase relationship issue here, but it didn't work very well. I don't like this pedal anyhow. I connected an old DOD fx65 Chorus pedal which I normally don't like either but it actually complemented the RT-20 swirl. Turned it into a monster chorus but that's something I won't use. Would have been great back in the 80's, LOL. I tried a Ibanez FL9 in front which sounded very good.
Distorion is pure mush for guitar. Not useable

Don't forsee any reliability issues from this device. Boss has been around for years, they have a reliable switching system and robust mechanical pedal design. I would gig this pedal without a backup.

I did email to ask about the stereo operation. Received same day appropriate response, BTW Rt-20 is not 2 channel stereo but a blend.

I did significant research on the currently available rotary pedals. I found the youtube demos to be marginal at best. Some are just plain atrocious. Most of these videos contain too much talk and then the individuals demoing the pedals don't demonstrate the nuances that these effects are about. Are you listening proguitarshop?

I started to focus on the RT-20 and Rotosim. Even the rotosim MP3 downloads, and Boss vids are marginal. We're all so subjective creatures so you have to try any pedal before you buy. I played an RT-20 at Motor City Guitars prior to this purchase, unfortunately they did not have a Rotosim. I read a couple of blogs and finally found comments from an individual that made sense at Gilmourish.com. I managed to find an RT near my home for a reasonable price, so I purchased it.

I play mostly blues /blues rock. I started playing a week after the Beatles were on Ed Sullivan :) the late 60's and early 70's keyboard bands are my favourites and of course the great Government Mule. My main sound is straight into the amps, the RT is for fun & color. I'll be using this pedal for the rythm parts of slow blues tunes. I think it is a perfect match for my playing style and music genre.

I wish the pedal had seperate horn and rotor outputs, separate ramp up and down speeds, and the ability to EQ (emphasize) the horn on acceleration and the rotor on deceleration. Most leslies you hear on a recording and live for that matter have at least 2 mics. This gives the opportunity to fade the mix to emphasize the doppler on acceleration and the amplitude modulation on deceleration.

Over the years I've owned A 67 ash bodied tele, a 50's Les Paul junior, a70's Les Paul Deluxe, a blonde 65 Fender Bassman, played through a Fender Showman and Traynor Bassmasters, ART sgx2000 Xpress with a stereo power amp etc. found my sound 8 years ago with the Chieftain, then 5 years ago with the DC-30 clone & the Chieftain. The Lado is my favorite playing guitar(a gift from my wife).I love the sound of the strat as well. It is a very expressive instrument.

The unit definitely helps make music. I have moved from in front of the amp, into the tube buffered parallel effect loop on the chieftain(addition) It can add very nice controlled color to a tune by appropriately timing and hitting the speed switch, I sometimes get goosebumps when I play with this . Nuff said!

Very easy to use. Keep it on the first choice(122)

Im using this now with a Hammond M3(Baby B) through a Fender Princeton.

Let me say that I was looking/struggling to find the "Leslie" sound without purchasing a 122. Let me just tell you right now. You cant get a 122 sound from ANYTHING other than a 122 or a "Leslie" type speaker of the same physical and mech. specs. So stop looking.

I have owned MS Pro3x and currently* own the Motion Sound Pro 3t/Low Pro. It sounds great but these units are old and moving parts will eventual fail. Plus...its heavy and my back hurts.

So I like the Lonnie Smith, MMW ,Robert Walter sound on the Hammond. The Choral/Trem of a leslie is important but I really wanted the tone(Tube Drive).

My Pro 3t/Low Pro comes close.

This Pedal NAILS IT. Just a Little Dirt on the dial and a mix with Dry(Direct) and "Effect". Bang!

So far so good.

Playing JaZZ Funk for 10 years...If you need the Third/Perc setting and you want a nice clean sound you can get it. If it was stolen I would def. get another one. I love that it doesnt break my back and sounds "Bossy".

I havent played it though a keyboard amp just through guitar(not stereo) and it just sounds great.

The Boss RT-20 is a Leslie speaker emulator based upon the Leslie 122. Its four modes offer two choices of mic position, a Leslie emulation fronted by a Marshall 1959 emulation (John Lord fans take note), and a Univibe emulation. A variable drive control is supposed to emulate an overdriven Leslie power amp, but falls short of the real thing by being dark and muffled-sounding. Fast and slow speeds as well as ramp time are all adjustable. A bicolored rotating display which indicates rotor and drum speeds is not as distracting at it appears it might be. One foot pedal turns the effect on and off while the other toggles speed. Pressing both pedals simultaneously sets or releases the brake.

Aside from the issues with the drive sound (which can be disabled) the RT-20's Leslie emulation can be fairly convincing. The trick (counter-intuitively) is to mix the direct and effect sound using the individual controls on the panel.

It took me a long time to warm up to the RT-20. If you're looking for an authentic Leslie sound it's going to take a bit of tweaking to get it right. (I have a real Leslie 147 for comparison.)

I play a pair of Koll DL Thinline guitars into various clean amps or a DI into a venue's PA.

The RE-20 can do a fairly accurate impresssion of a real Lesiie, but it takes patience and a good ear to find the right settings. If all you want is a some kind of mutant swirly sound then the RE-20 can deliver.

I've had the RT-20 for seven months. I don't expect to have problems.

I don't expect to have to contact Boss for support.

I play improvised fingerstyle guitar in a style that I call "psychedelic folk jazz." The RE-20 contributes nicely to the "psychedelic" aspect of my sound.

I started playing in the mid 1960s and have been playing seriously for eight years.

I've played a lot of other Leslie emulators. Although the RE-20 is far from being "plug and play" (the Leslie mode of the Digitech EX-7 walks away with that award) it has a pretty good sound and a good interface (on/off, fast/slow, brake).

I could do without the spinning display. Although it's less distracting than one might expect, that's faint praise. The display really doesn't add anything to the functionality of the RE-20. I'd like to see the panel space used for an additional control to independently adjust the ramp time of the rotor and drum.

While all the knobs are self explanatory in my opinion this pedal does take a while to get the sweet spots in. If your impatient then this pedal is going to be a very daunting task to work with. Whats great about it is the jack in the back for an expression pedal.
If you dont plan on using a power supply with this thing then you are a fool.

Getting one thing out of the way... strictly for guitar the distortion is absolutely worthless in any way. It just sounds muddy and digital.

Now on to the effect. I have had this box for about 5 months now. When I first got it the thing I noticed was the VOLUME BOOST. Kick this thing on and your gonna hear a distinctive boost. To get around this I have turned my effect and direct settings to around 9 o'clock to avoid a sharp volume increase, this does take away from the intensity of the effect though. The second thing I noticed is that when left off

The rotary sound is very nice. Setting one is a classic Leslie sound which is awesome with a clean guitar. Distorted it seems to get a little to harsh for me. On the higher speed it is easy as hell to get into "Any Colour You Like" tones.

Setting two is the one I use most. It is kind of like setting one and a subtle univibe thrown together. This tone is where it's. It has a more drastic spin on it.
Setting three I have found no use for other that weird keyboard stuff (which I forgot to mention, keyboards and thing box are tops)
The univibe sutting (setting four), is kind of subpar when compared to even the Dunlop reissues so I choose not to use it much. It does give a nice Trower's Hannah tone though if the intensity is turned up.

All in all Settings one and two are going to be your money makers. They are a true sound and easier to carry around than a real leslie. When you kick this thing on and sit next to your cab you can almost hear the horns spinning around inside... It's a pretty cool 3D effect.

This thing is tough. With all my pedals I take advantage of the warranty and throw them down my stairs (im serious) first plan. If they survive then I can use them. If they break then I take em back and tell the guy that I opened it up and it was not working. The reason I do this is because when I play live I have a habit of stomping the crap out of my pedals.
This is a Boss and all Boss pedal I have used have passed the test.

I take this on gigs and it hasn't failed me but if it does then I have a Phase 90 in my board that I would use instead.

Overall this thing is ballin. It gives you awesome rock tones from Trower to some AWESOME vocal tones (I recorded some vocal with this thing and it was perfect for that "Planet Caravan" feel).
I play in a psychedelic/fuck/rock Mars Volta/Hendrix kinda outfit and this suits our styles perfectly.

I run it through my chain as such.
Fender modded strat > Vox V847 > Ibanez Analog Man TS808DX > Fulltone Fulldrive 2 > Seymour Duncan Tweak Fuzz > MXR Phase 90 (modded for true bypass) > Boss RT-020 > Marshall DSL50

I have been playing for 10 year and gigging for 8. If it was lost or stolen I would drop some bills for another one simply because it is the easiest way to get the Leslie sound I want.

I have two gripes about it though.
ONE: The damn horn display is extremely distracting to me... I have an affinity for spinning lights and I often find myself looking down and my board cause this thing is so psychedelic.
TWO: when turned off (like with all digital effects) I can feel a slight digital tinge is my sound rather than if I were to take it out completely. Although this is not as bad as it sounds. I find my tone a bit darker with this thing is chain.

Overall, go try one out for a good hour and get over the volume boost... i mean come on use your volume knob for christ's sake.

This is an easy peice to operate. There is one footswitch to turn the effect on and off and another to change the speed of the rotary effect. The knobs that effect the sound are easy to figure out with minimal fuss. The manual is pretty simple to follow plus it gives a couple starter settings.

I have been using this in my pedal board with the following signal chain. 51 RI Tele>Peterson SS2 Tuner>Fulltone Fulldrive 2>RT20>MXR Carbon Copy>Fender Deluxe Reverb RI. I also tried it with a mid 70's Silver Face Twin Reverb.

When I first tried the pedal I set the eceffect knob at unity gain and nearly blew my eardrums. The pedal has a lot of gain so I turned the output to 3 o'clock and the direct signal at about 12 o'clock. This made it pretty transparant and when switched on not as jarring. Since I already have the Fulldrive so I do not use the OD that is built in the unit. I did try it, but found it really altered the tone of my guitar. If you already have a decent OD you can just leave this off. You can also tweak how much of the "rotar" and "bass" you want.

You can get most of the stock "guitar through leslie" sounds straight out of the box. It nails the Joe Walsh sound down as well as the George Harrison sound on the solo from "Let It Be". The Uni-Vibe effect however is a little to bright and in your face. It's hard to get a subtle sound from this mode. the other two modes I found not much variant in sound. I would give it a 9 overall were it not for the jarring Uni-Vibe.

Well I have e not useed at a gig and I am running it through a Visual Sound One Spot on my board so with constant power it is very reliable. I wouldn't use the AA batteries since this thing looks like it has a hefty appetite for batteries. I tend to run modulation effects through dc anyway.

Haven't had it long enough and I never had a problem with Boss effects through the decades I have been playing.

Keep in mind that this is part of Boss's line of "Twin Pedals" so it has a larger than normal footprint. If your short on real estate on your pedalboard you may want to take this into consideration. With other Leslie simulators on the market this is one of the best sounding units available at a decent price. I have seen others that cost twice as much and if your going to pay that much for a leslie simulator you may as well just get a Motion Sound cabinet.

I play mostly 60's style rock as well as country and blues. This is a pretty flexible great peice of gear. If you want that tone from "Badge" it's here. It is a very musical effect.

I find the 4 position mode switch is lkind of unnecessary since the 1 st postion gives me everything I want. It seemed to me a little bit of overkill but that is what makes it flexible.

The controls are simple and it's very easy to adjust the settings to recreate classic Leslie effects. The brake control can be a little difficult to engage if the pedal isn't sitting perfectly flat or firmly anchored in a pedal board, but that is a minor complaint. It's also a major current drain so an AC adapter is a must.

My main instruments are a 1975 Gibson Les Paul Deluxe and a custom Strat with active EMG's played through a 50W 1981 Mesa Boogie Mark II. The rotary effect works very well with my rig and I am easily able to recreate every nuance of the classics - everything from Badfinger and George Harrison (Badge) to early Zep (Good Times Bad Times), Joe Walsh and SRV.

It's Boss, built like a tank. I've never had any problems with anything from these guys in more than 25 years of professional gigging.

Don't know... never had any occassion to need customer support for anything from these guys.

The effect isn't for everyone, but more than fits the bill if you're looking for a decent Leslie sound for you guitar rig and don't want to spend a fortune or deal with the space/weight of the real thing. I am extremely pleased with it - my only regret is that I didn't get one sooner.

It's a little more complicated than your typical effects pedal but it's not rocket science either. The controls are pretty intuitive and it's not difficult to get a decent sound from the RT-20. In fact, there are a few good sounds to be found here. The most difficult part is setting the levels (effect and direct) which is where most users probably start complaining. I've found for most curcumstances to keep the levels between 9 and 12 o'clock in order to keep the thing from boosting the volume too much. Other than that, it's pretty easy. Just fiddle around until you find what you like.

The RT-20 has awesome sound to my ears. I've had the Hughes & Kettner rotary pedal, an old Digitech RPM-1 rack (both had tubes), a Lexicon Vortex, plus I have the Damage control Glass Nexus (which is an amazing multi-effects pedal worth checking out) and the RT-20 has that swirling, gritty rotary tone. It's not a clean effect, it isn't s'posed to be. It can be fairly clean but it's a rotary unit, if it is emulating a real Leslie is going to be a little dirty. I do agree that the overdrive gets unusable anywhere past 9-10 o'clock (at least for my tastes) and I usually only turn it on a little, but that's not why I got it. The speeds are good and usable and it does have a brake to stop the swirl; it does everything a rotary should. It's not a Leslie so stop expecting it to be, but it does do the job very well. By the way, put the Boss RE-20 Space Echo after it and whoa ...

I've never had an issue with a Boss pedal in 15 years.

See reliability.

The RT-20 is a great value considering other pedals that do the same thing cost more and don't sound that much or any better depending on what you buy. I've been at this for 30 years and go through trading gear a lot, so I know what's available and what sounds good. Right now I'm using Damage Control pedals and a few Boss twin pedals and an AdrenaLinn III and a Boomerang, but I've had Lexicon, TC Electronic and Rocktron racks plus E-H, MXR, Line 6, Boss, Pigtronix ... pedals. For some reason Boss pedals always seem to grace my pedalboard.

The RT-20 is really easy to use. In fact, I ended up with all speed settings on 12 o'clock and the Leslie model I because that comes closest to what I wanted my sound to be like.
The only tricky part is the overdrive. I think that even in "keyboard"-mode it's a little too sensitive.

The RT-20 isn't as much "tweakable" as the Korg G4 or some Boss multi effects, but that's fine with me. It sounds good out of the box.
Oh yes, and you can't save anything as a preset. But in turn you've got knobs! No menus, no display, no questions - just 8 knobs to turn, and that's great!

Minus: They forgot a jack for a foot switch. Only an EXP-pedal is possible - but that doesn't make too much sense for an organ player. Pity.

I'm using the RT-20 with my Hammond XB-2 II to make it sound like an organ. If I have to bring my own stuff with me, I've got a Yamaha MG-10/2 for mixing and a Dynacord AM-12 active speaker.

The rotary simulation itself is the best I've ever come across. Of course you can't simulate the projection of a real Leslie, but it certainly comes close, especially if the speaker is at a little distance, so it gets some "air".
Overdrive is ok, but as mentioned above a little hard to adjust. If it works once, it sounds pretty authentic. Usually I have the overdrive set at about 10 or 11 o'clock and the volume on my Hammond XB-2 around 9. The output signal is pretty quiet, so you should use two mic inputs on the console, but the sound justifies that.
As I'm playing jazz and funk, I stuck to the rotary model I (122 with 122 drive, miking a little off), which is perfectly suited for that kind of music. It really sounds like it should.
Also nice: You can control the amount of distortion with the expression pedal, like real tube gear.


I rarely use the other models. The 122 close-miked is ok, 122 with the Marshall drive, too (but not suited for my music) and the UniVibe is nice, but I don't really need it. Furthermore it's pity that the overdrive on the UniVibe reacts so harshly. It would be great to give it just a little saturation without screaming distortion when playing with the Rhodes - but that's very difficult.

However, as I bought it for my organ, I'm fine. Once the drive is set, it sounds really good.

Should be ok. I've been using it for a year now - no problems at all.

I've never contacted Boss.

For jazz organists I think this one is a good choice. As I said, I've got about everything in the middle position, the 122 off-miked and drive adjusted to taste. Of course that doesn't convert an old XB-2 into a pristine B-3, but it's close enough. Next step up would be a real Leslie.
I've been playing piano the most of my life (about 18 years out of 22) and Hammond organ for 1 year. I'm using the XB-2/RT-20-combination with my organ trio (w/ guitar & drums) and have always been satisfied. Yes, it greatly helps me making music, as it makes the XB-2 sounding like an organ!

Nothing difficult about it. A knob for every parameter, it's a no-brainer.

First note that I'm using a real Hammond C2 with this, and would have a real Leslie if they weren't so much money, but I have played through them and I hear them in person several times a week...whether I'm sitting behind the organ or not.

Well the big complaint I see from people is the overdrive. I hated it at first too, but I found myself loving it after getting it set right. IF you just crank it up halfway and start ripping real loud on your instrument, then it sounds horrible. You gotta make it very subtle and then it is very realistic to a Leslie.
So what I do is set the overdrive "on" at the absolute minimum setting. I put the organ volume on max. and adjust the 1/4" output until the overdrive is at the maximum amount that I want. The trick here is that the overdrive is volume-sensitive, which is true to the Leslies I have played through. With it set this way, it gets just a little dirt as you get louder. But remember, minimum setting...just a little dirt, and make sure the max volume you put into it is set where it is only at the max amount of dirt that you want.

Everything else is good. I like that the horn and bass speed up differently. The default speed and ramp settings are realistc, although I tweak them about a centimeter just for my taste.

I thought it had some digital coloration at first, but I notice it less now. It may just be me getting used to it, but even after time away from it and hearing the real thing, it sounds 99% of the way there to me. What's really lacking is the 3-D sound of a real Leslie...with the sound bouncing off all the walls. That doesn't happen with any pedal and it simply can't happen without the physically rotating speaker.

For organists, whether you have a real Hammond or a clone, I think this is the best pedal available (but depending on what clone you may not even need this...mainly the older ones would benefit from a better sim). For guitarists the story may be a little different. I'm not a guitarist and I don't ever play a guitar through a Leslie so I couldn't tell you.

It's very sturdy, and always works flawlessly, I can't imagine it failing on me.

Have not dealt with them before but everybody I hear from says they are exceptional.

I would give this a 10 except for the price. It's a fantastic pedal and gives credence to "you get what you pay for," but it still seems expensive for a pedal these days. They could have at least included a power supply at that price. But I had an extra Boss adapter anyways...so it worked out fine in my case. With other pedals like the Line 6 at $120, it's tempting to get that instead, since it is also a good pedal and $100 cheaper, although it sounds a little less realistic.

But like I said above...for organs this thing sounds amazing. Guitars could be a different story...ask someone else because I don't know. :)

I got it since june-06. It's very simple, it's too much simple... now I want more parameters!

It sounds good? This is the question. YES and NO is the answer. It have a strange EQ leslie simulation. It truncate high frequency, but without a good filter or a good algorithm job... it seems a digital 16khz(or less) recording auto-cutoff: this produce non-accuracy high sound details, and a acute frequency enfasys in mid-8khz(or less) circa(my ears response..). The Balance knob don't help us.
I've tried it in many ways: in live through big speakers, with my band in a room, in my room through my Esi Near 05 monitor, with my old Yamaha Electone C-55N, with the Roland RS-5, with NI B4 II.
In Live or with the old Yamaha, it sounds good, very "rocky", very loudy, with an emotionant fast rotary speed, very simple. Plug and play.
The "secret" for use the "distortion" is give a VERY LOW signal input to the RT-20: this get the sound dirty, but I agree with other users, the distortion is not good.
With the B4, in studio, it sounds bad. I don't know why. In comparation with the leslie 122 simulation of the b4, the RT-20 lost.

I play funk, soul, blues-rock organ. It doesn't sounds jazzy, his sound is more usable for rock or for electric guitar IMHO. It's the best solution in live.

Well,,,,this is my second review as I've read so many reveiws here where there were so many disapointed with it, I thought I could give some feedback as to how one can get the best of this pedal.
I't's easy to use, but how you use it & in which signal chain you choos totally makes a difference of the performance of this great effect.
Bear with me,,, as I know there are not many people that run their rig the same way that I do, but this is where this unit will satisfy, no doubt in my mind.

I've tried this pedal in every way possible.
With guitar I've found that using the RT20 parallel with the mic signal chain is the best way to get the this pedal to sound as authentic, warm, & close to the real thing without playing with, or sucking your tone.

I run my rig as follows,,,,Guitar to my analog pedals,( overdrive, boost, wah, ect) then into the amp.
I don't have an effects loop as most of my heads or combos are vintage, besides, I don't like them in general anyways.

This leaves all my time based effects out of the amp, which I prefer as I seem to get better tone, definition, & balls this way.

What I do, & there are some others that have found this method of running time based digital effects to be far better, is run my mic (E-609) to a rack with a midiman line mixer, this unit has a very good mic preamp, it also has an effects send that works quite well indeed. I run the RT20 by routing the send signal to the input & I run the outputs into other channels in the line mixer & set the direct level of the RT20 on zero & the effect level full, so there isn't any of the direct sound coming out of the RT20, just the effect.
The direct sound is parrallel & unadulterated by the digital effect.
If you are skilled in setup of effects & tweaking, your ears will thank you.

This method has some drawbacks though,,,because in order to monitor your effects, you need a dedicated power amp & full range PA speakers.
To some this may be out of the question, but I use a Yamaha P3500 & a pair of Ramsa stage monitors, & there is no question that this rig sounds just killer to say the least, so I don't mind bringing it anywhere.
If you have a good soundman & a dedicated house monitor, you could get away with that as your soarce of referance too, but I've known guys to run the "wet dry wet" set up & haul even heavier stuff than me, & not even come close to the tone I get by running effects in the mic signal in parrellel & using my own dedicated small PA.
As I stated in my previous review the overdrive sounds like crap, but using it the way I described, I find I get that sound of the leslie growl with the overdrive completely off.
If you have the means to try running your effects this way, try it.

I give this pedal a 10 only because of the results I get by using it in this way, I agree with most, in front of an amp, this thing sucks.

Boss, need I say more?

Roland, need I say more?

I play guitar, I have good ears, & I know how to set up & tweak effects.
If more guitar players would have the patients to learn about how to use these tools to the best of there tonal benefits, there would be less bad reveiws.
I get an extremely good simulation of a leslie with the way I use this pedal, & I know what one should sound like as I have a real Leslie 147 as well.

Not easy to get a half decent sound with a guitar.
The best settings are: Mode:1 Rise:Noon Balance:full left
Effect:9:15 p.m. Direct:full Slow:full Fast:1 o'clock

It changes the tone of your guitar whether it's on or off. It brightens up your sound and gives it an awful digital tone, even when the effect is just slightly used. If you're like me and have a nice warm tube amp tone with all analog pedals, you won't like this unit.

It seems well built

Don't know.

I've been a pro lead guitarist for 16 years and play stuff like SRV, Hendrix, blues, rock etc. I've got really nice older Strats and vintage Fender tube amps with analog pedals. If I were to put this pedal in my box, it would ruin my tone whether it's on or off.
I do not recommend this pedal at all.

Very simple.No manual needed.

Good Leslie simulator.I use it with my Hammond A100 and Voce V5 wannabe.The only cons are :

1)the overdrive which is orrible matched with organ sound : sterile and harsh, 1000 miles far away from the warm tube overdrive of the real thing

2)the differences between the four models aren't noticeable (except for the Leslie16,monorotor,simulation)

3) too emphasys on higher frequencies

In a live contest is realistic,but lacks a bit of "wow" (depth in modulation) ; on recordings it gives a really good Leslie sound (if you keep the overdrive on "O" and adjust with a EQ the high frequencies!)

strong metal case

Good Leslie effect

Straight out of the box, well, it's as easy as you expect an FX pedal to be really....

It's not noisy... The overdrive is really terrible, but can be overcome if you keep it on "0". I use it with a tube mic preamp between my Hammond L122 and the PA and it sounds immaculate.
The rotary ramp up and ramp down is extremely convincing.

Would reccomend for any gigging keyboard player as a portable alternative to a leslie cabinet.

It gets a 9, but only because you have to use a seperate overdrive.

Absolutely 100% reliable.

Not required yet. Cannot comment.

For organists, especially where you'd be through a PA, this is virtually indistinguishable from the real thing. The distortion is totally unusable, but easily overcome. It's easier to set up, no mic'ing required.

It's obviously a hell of a lot cheaper than a Leslie 122, a lot easier to find, and half the price of it's nearest competitor- the H&K tube rotosphere.

For that reason, I'd reccomend it to any organist.

im a pretty smart guy so usually i put 10's here and scoff at anyone who cant figure out a pedal... but this pedal is not exactly care free use. not that its hard to figure out, especially w the manual, but just the way they have you interfacing with it in my opinion could be better...

as others have said, i really wanted to like this pedal. i went down to guitar center with 95% intention of buying this pedal and EV-5 expression pedal, and left with nothing.

Here is what i thought:
1) there is a volume problem. i found almost any setting has a noticable and annoying volume increase. i can get it to be very slight, but this is by reducing the mix of the effect, so you cant hear the effect that well !! its like solving the problem by giving up...
2) there are 4 settings, but i find as an "amature" to rotary sounds, there are only 2 discernable sounds. 1 and 2 sound exactly the same, and kind of like 3 or 4 too, but i forget which one sounds like which exactly.
3) over drive sucks
4) i play in stereo, and im trying to move all to stereo pedals, which this one is. only problem is that if i put it in front of my distortion, it sounds like utter $H!T and is basically toilet paper. if i put it behind distortion, it sounds ok, but then its not stereo anymore cuz i dont have a stereo distortion pedal ! (props to anyone who can suggest one)


I really wanted this pedal, one dumb reason being i hear this effect on the new tool CD and also would love to be able to manually ramp speed, but after testing in the store, i couldnt justify buying it. i was heartbroken....

would love it if anyone could suggst a better pedal !

bad pedal but im sure its reiable as boss ususally is. although i do have a DD3 a few years old that broke...

no clue

sounds cool, but not usable at all i think

As others have said, the controls are simple and the manual is good.

I'm a keyboard player using this with a Viscount D9 organ, and into a PA. No other effects. For practice, I run it through a little Roland bass amp.

First off, as everyone else has said, the overdrive is not just disappointing, it's totally unusable. Fortunately, the D9 has an onboard overdrive that is way more satisfying, and easy to adjust on the fly while playing, so I don't really care about the OD.

I use the first preset 99% of the time, switching to setting IV for more of a radiohead sound sometimes.

At slow speed, the thing is lush and fairly realistic - at least as good and likely better than most any onboard leslie sim I've heard. Kick it into fast and the high and low ends ramp up at different speeds. Very realistic.

At fast, well, you're not going to mistake it for the real thing, but damn, it sounds really, really good. I find with some onboard distortion in front and the rotary on fast, you can get some of the bite and snarl of a real B3/leslie combo.

Toggling speeds and braking, you can really add a realistic texture to your organ sounds. I tried running my Yamaha SY77 through it for fun (you'd be surprised just how great a B3 simulation that synth can accomplish with the right patches). Again, it takes a thin, digital patch and adds real life and dynamics.

Haven't owned it long. So far so good. It seems really sturdy, and is standing up to regular stomping so far.

I ordered this before it was released. Roland/Boss delayed shipping any of these for months later than planned due to a parts problem with a supplier. I know that because I emailed them to ask what's up, and got a prompt and courteous reply from a real human. Like, within 24 hours. Impressive.

I use this thing for a lot of organ sounds from B3 simulation to overdriven Wurly to Farfisa. The Jam, Elvis Costello, Steve Miller, Talking Heads, Counting Crows, K-OS, Radiohead, and lots of other crap. Real mix of 70-s to present.

Look, if you are buying it for the overdrive, then just say no. If you want a Leslie sim that is reliable and fits in your hand, this thing is truly a blast for a keyboard player. Fatter, fuller, better sound.

Not too hard to find settings for a good sound, just tweek a few knobs.
the manual is fine, explains in enough detail

using fender strat custom shop 69 and mesa F-50 amp and badcat 2x12 cab

Now in bypass, its not too good, sucks tone, and if I use a fuzz pedal in the chain there is added hum and noise. But when its switched on, that extra noise and hum is gone and the rotary effect sounds fine.

The pedal does make a fine sounding leslie simulator though, and the uni-vibe is cool, although it may sound a touch digital, thats coz it is digital, it still does a fine job.
I can get a cool uni vibe sound like pink floyds - breathe.
and enjoy using the leslie setting for playing little wing by hendrix.

Also when using a wah in front of it, sometimes a kinda distorted overtone happens, if i push down on the wah fast.

The onboard overdrive doesn't seem to be popular, and I agree, it doesn't sound too bad when the speaker is stationary, but I don't like distortion, i prefer to use fuzz pedals and they sound cool running thru it.

I can depend on it, and would use it without a backup. only had it a few weeks.
its not an important pedal for live situations, so if it fails it wouldn't bother me

never dealt with the company

I'm into the late 60's and early 70's psychadelic, rock, funk sounds, like jimi hendrix, pink floyd, funkadelic.
It is a fine match for getting me leslie and uni vibe sounds, it does the job.
If it was stolen, I think i might check out the voodoo lab micro vibe, but I might consider another RT-20 if at a low price.

Just the bypass annoys me the most, but anyway, this pedal does the job, and I was able to get it at a reduced price, so I grabbed it.

still i might end up getting a voodoo lab micro vibe for the uni vibe analog sound.
but nothing will sound like a real leslie so this pedal does the job and i enjoy it. It's cool, but I wouldn't of paid the full AUS$500 for it. So I give it a 8 for the price I paid.

There are lots of parameters to tune in a possible useable sound.

The actual leslie simulator is quite good for guitar(which is what I'm reviewing this pedal for), but the the overdrive sound is really sterile sounding. Even with no overdive dailed in, all of the settings have this horrible digital overdrive overtone.

Didn't keep it long enough to rate.

N/A

IMO,unusable for guitar.

Very easy to use. Manual is pretty straightforward.
It is easy to get the best sound out of it you can get out of it...meaning, you get it at it's best right out of the box.

Well designed with the potentiometers which, on the parameters where it makes sense, it "notchs in" to the position that is default.

All my testing/playing of this was with a MIJ Strat, going through a Octron->Jekyll & Hyde->Digitech Tone Driver->**RT-20**->H2O (Chorus/echo)-> Bassman clone, also tried it in stereo to two amps, once with Bassman + Classic 30, once with Carvin MTS3212 + Peavey Classic 30.

Put succinctly, I had high and realistic hopes for this pedal. I really wanted to like it. I already have a couple of vibes (Mojovibe, Deja mini vibe) and the H2O pedal which has a "Leslie-style chorus", and I have had other (Captain Coconuts 2 and others) but reading the reviews on this pedal I was very hopeful about it. I know how a Leslie sounds and some reviews of this were to encouraging.

So I waited for it, and when I finally got it (was shipped new to me) I was rubbing my hands with glee, and told my wife I'd probably be down in my basement music room...a LONG time. I'm no kid, and have been playing for over 30 years and I am just mentioning that because I want to stress I had realistic high hopes for this pedal. I KNOW absolutely no pedal can truly recreate a Leslie sound, but from reading about it was hoping for that "vibe" and closer sound to what a Leslie is.

I also didn't get dissapointed right off the bat, I played around with many (all) of the knobs, trying to see what I could get out of the pedal...this is what I found.

The "overdrive" as some have mentioned, really sucks badly. I was prepared for this after reading reviews here and in magazines even. No surprise. I have great OD's I can use, I didn't feel a need for it anyway, so though I checked it often just to see if it was as bad in every setting, in every mode (it was) mostly I had it off.

The overall sound was thin, and very dissapointing. I tried all modes, I tried adjusting the "Direct" (how much, if any, of the direct sound mixed in with the effect sound) from off on up on all the settings. I tried adjusting the "mix" of bass and treble (horn and woofer) differently...it seemed to go from thin, right over to dark and dull sounding...nothing in between.

The plus side, the slow/fast setting, and rise time, and the fact that it ramps up like a real one IS pretty cool! I wonder if this pedal wouldn't be a lot better for organ or keyboards. Even though I thought this was cool (and is a major, or THE major selling point actually) realistically...it isn't worth the pedal space. I mean, okay, it's cool to us guitarists, but how often in a song or solo do I want to go from fast to slow? Even if a lot, my Mojovice accepts a expression pedal and I can "ramp up" manually if I really want to.

I have my Mojo vibe on my pedalboad, but tested this RT-20 against my other vibe (I like the mojo vibe better than the mini vibe), the Deja mini vibe. Also the H2O.

Just to mention, the H2O Chorus side has three knobs only...SPEED, WIDTH, and DELAY...with those three simple knobs I could duplicate the basic sound and feel of any setting I had on the RT-20, BUT with the sound being MUCH more up-front, non-digitally sounding, more "real" sounding. I mean between that and a decent vibe, I found myself seriously wondering what the magazine reviewer was smoking. This sound LESS like a Leslie to me than the H2O.

I really think the selling points they targeted for this unit were the ramp up/down when changing speed, and the "nifty" display.

The nicest mode in my opinion on the unit was the first one. Maybe a little of the "II" one also. The "univibe" was really nasty. It sounds way too digital to me as well. It sounded a good deal better in stereo (of course) but not THAT much better, and here too...my H2O does two outputs also, and beats the hell out of this pedal there as well.

It is a huge pedal (I used to complain about the size of the H2O) and to take up that much space it needed to be lots better than it is.
I would really recommend anyone interested in this to audition it for themselves at the music store, AND try and H2O (which also gives you an Echo!) and see. It might be just my rig.

This pedal made me really appreciate my H2O again. I haven't had many choruses (except in ME effects) and didn't realize how much I liked the H2O one, and also matching up against the RT-20 made med reexplore the possibilities with the different settings.

This was a real dissapointment, but if I had no chorusy/Leslie effects, it could be useable. It isn't a "terrible" pedal by any means, just does not live up to all the hype SOUND-wise.
Features are cool (the LED is a little much though...)

I play blues, Hendrixy, SRV'y, Trowery, but also Buddy Guy, Pink Floyd, Stones, JEff Beck...anything. Have been playing for 30+ years. Have a lot of experience with effects in general, though just a few Chorus pedals experience, outside of Multi-effects.

I am returning the pedal as I write this. It isn't terrible, but it is not worth the money to me. I am kinda grateful that this has given me new appreciation of my H2O pedal though. Matching the sounds of the RT-20 (but the H2O made them sound better!) gave me more practice dialing in sounds on the other, and that was worth a lot.

Love the ramp up/down on the RT-20. It is a great idea. I may be the only person on the planet that wasn't turned on by the LED display though. It looks cheap and gaudy and my ears tell me where it is set way better. It can be misleading even I think.

I wish it had better sound.

Fairly easy to use, especially considering all the parameters that could be adjusted. As a starting point, I put everything at 12:00 and let fly--then I tweaked as I saw fit. I ended up with these approximate settings (but this is subject to change);
Treble/Bass Rotor Balance 2:00 (more bass than treble)
Overdrive: OFF
Direct and Effect adjustments both set to ~1:30

I liked preset 1 the best. The manual was good--very thorough.

My setup is as follows:
1980 G&L F100 Series II--or--1962(RI) Fender Stratocaster--or--
1995 Fender Telecaster (converted to 1953 Esquire specs)-?or--2000 Danelectro DC3--or--1940?s Astatic AS200 Harp Microphone (with various Lee Oskar and Hohner Harps)
--going into--
Boss TU2 Chromatic Tuner
Ibanez TS9 TubeScreamer Overdrive
MXR Phase 90 Phase Shifter
Dunlop Original Crybaby Wah
Boss RT20 Rotary Ensemble**
Danelectro Daddy-O Overdrive
Dunlop Jimi Hendrix JH2S Classic Fuzz
DOD FX40B 7-band Equalizer
Rocktron Hush Noise Reduction Pedal
Morley ABY Switch Box (into Normal and Bright channels of amp)
All pedals mounted on/powered by Furman SPB8 Stereo Pedal Board

1963(RI) Fender Vibroverb Amp (the one with brown Tolex and 2 ten-inch speakers)
(Mic?d with Shure SM57)

(I know that seems like a lot of pedals, but I can get any tone known to mankind with this setup; I use so many guitars because of alternate/slide tunings. I also run my harp through the effects).

The RT20 performed great! During sound check, I turned it on, and immediately both of the sound guys (both good guitarists in their own right) came up to the stage and started peppering me with questions. The other guitarist in the band also was impressed with the sound quality and realistic-ness (is that a word?) of the effect. Even the kids at the gig (we were playing a company picnic that had many families) were impressed--mainly because of the lightshow happening on my pedalboard. My harshest critic--my wife--told me after the gig that that was one of the best-sounding effects I have ever used.

As far as sound quality, it was dang near perfect--it was not noisy at all (which is a major issue with many other Leslie simulators), very dynamic and "alive" sounding--not processed or "digital" at all. It was warm and rich, (also an issue with some other Leslie simulators).

SWIRLY!!

I got a really great tone for my own compositions that call for a Leslie cab ("Travis County Line" and "Monkey Hips") and a very good "Cold Shot" SRV-like tone. It also worked well for the Jimmie Vaughan/Fabulous Thunderbirds song "Tip On In".

The only criticism of the effect is the overdrive--it just turns the tone to crap. To get some overdrive on the tone (a la "Cold Shot"), I set my Danelectro Daddy-O to the "Texas Blues" settings found in the Dano manual and placed it AFTER the RT-20 in my signal chain. When I turned on the TS9 TubeScreamer (BEFORE the RT20 in the signal chain), it had the same harsh crappiness of the overdrive function on the effect itself.

We recorded the gig, and the producer/drummer said the effect recorded great, too after listening to the raw mixes.

I liked the "ramp up" and "brake" features--it added to the realism of the effect.

I just have to comment again on the quietness of the pedal--that just puts the cherry on top of the sundae.

If it weren't for the uselessness of the overdrive, I would give this category a "10+".

Boss pedals are very reliable--I bought a severly abused DS1 distortion and CS1 compressor/sustainer from an angry guitarist (he took it out on his equipment) and both worked great--even after his mistreatment.

I also have owned a TU2 and a CS3, and both have been extremely tough and durable (although I was disappointed with the CS3's tone).

I will gig without a backup.

I have only contacted Boss once (directly after I bought the RT20), and they were extremely helpful and straightforward with me. One previous reviewer gave them a poor rating, but he hadn't even contacted them--I think he said something to the tune of "I can't imagine they would be helpful considering how big of a company they are".

I contacted them because I was concerned about the mA rating of my pedalboard's power supply being too low for the recommended rating of the RT20 (the Furman SPB8 is rated at 100mA, and the manual recommends the PS19 wall-wart which puts out 200mA). I went ahead and sprang for the PS19 to prevent the RT20 trying to pull more amperage out of the SPB8; this will extend the life of the pedal.

The operator was helpful and friendly, and I didn't have to wait on hold too long.

I play guitar/slide guitar/harp/vocals Texas Roadhouse Music (combine varying amounts of blues, rock and Outlaw country) in a Fort Worth, Texas-based group called the SCREAMIN' ARMADILLOS. Someone described us as ZZ Top and the Fabulous Thunderbirds touring with Waylon Jennings.

This pedal fits in perfectly with our style (and specifically, my playing/picking style). Texas Roadhouse Music just begs for a Leslie-effected guitar.

I've been playing guitar for 17 years, and I've been looking for a good Leslie simulator for 15 of those years...I finally found one that satisfies what I want out of this effect.

I have tried and compared the H&K Rotosphere (too noisy, big, brittle, and expensive), the Line 6 MM4 (too digital and kind of expensive), the Danelectro Rocky Road (just...no), the Line 6 Stompbox (too brittle and noisy), the Jim Dunlop Rotovibe (just not "right"), the Uni-vibe (like the Rotovibe, it's just not the same sound as a Leslie), the Peavey Delta Stomp (pretty close, but it just is slightly too vanilla and digital-sounding), the Rotary setting on my Line 6 POD (it was "ok", but too digital-sounding, especially for live applications) and the Electro-Harmonix Wiggler (too vanilla). The only things I've ever been satisfied with before the RT20 are a Fender Vibratone (a real Leslie-like device that costs and weighs too much), a Motion Sound unit (also a real Leslie-like device that costs and weighs too much) and a real Leslie (again, cost and weight).

The RT20 wins, hands down!

If it were stolen, I would hunt down the poor fool and make the rest of his very short life VERY miserable, and then gently put the RT20 back in my signal chain.

I like everything about the product (sound, price, and looks--that light show is awesome) except the overdrive; but with my rig, that wasn't an issue.

One last thing--my wife bought this stompbox for me for our wedding anniversary (I only had to drop two hints; she also bought me the Daddy-O, the Hush and the Furman pedalboard on other occasions). That proves that I have a dang good woman in my life.

easy enough to use and i like the flexibility that it provides. there are controls for horn/drum balance, wet/dry balance, overdrive, fast and slow speed settings, ramp time and 4 global settings ranging from traditional leslie to u-vibeish type stuff. i pretty much just set it and forget it. also the dazzling light show let's you know visually how fast the thing is spinning.

i really wanted to like this pedal. it is cheaper than the H&K and has more functionality than the option 5 for a similar price. plus it looks so damn cool on my board. unfortunately, it sounds like crap. the overdrive is worthless, i won't use it all. i'm almost positive that it is not true bypass and i swear i can hear it when the effect is OFF!!! all of a sudden i was getting all this digital crap in my tone even when i wasn't using it (i use all analog effects, except digital delay, in front of a hot rodded customized vintage super reverb). when it is on it sounds very glassy and digital not to mention about 3-6 dB of level increase when kicked on. i ordered an option 5 destination rotation and am returning the RT-20 immediately after a few gigs. thank god for 30 day satisfaction garuntee's at guitar center.

i'm sure it is pretty reliable as are most boss products. i've had trouble with digital gear in the past. it tends to get all beat up on the road, even in expensive flight cases. my line 6 MM4 has been rapidly deteriorating due to the mother board and switches rumbling around on a trailor. that's why i bought the RT-20.

never dealt with boss before. can't imagine that their very friendly or helpful being that they are a massive company.

i wouldn't reccommend this to anyone who is a tone freak like me. hopefully the option 5 works out but i have a feeling i'll end up with a rotosphere. if only they weren't so damn big and expensive. i like the classic leslie sound but i also really like the swirly, psychadelic vibe that you get from the rotosphere spinning real fast. who knows, i may even end up with a freaking songworks rotating speaker. gear addiction is a serious problem, they should invent some kind of counseling for it.

It takes some tweaking to get the best sounds, the factory suggested settings in the manual are OK but it's best to use your ears to tell you what sounds the best.
The manual could be more specific on the use of the continuous control pedal option, especially when using it for the brake function.

This pedal is a great leslie simulator, for either guitar or keys, but with all things swirly there are a few minor shortcomings.

First the shortcomings,,,, the overdrive sound of this pedal set anywhere past off sounds like poo.
& it doesn't sound as good as my Leslie 147.

Lets face it,,, if those are the only shortcomings that this unit has, then we have a winner here folks!

I bought it yesterday & spent a few hours putting this pedal through it's paces, I came to the conclusion that the actual rotory speaker simulation with the ramp up & down & the horn & rotor rotating at seperate directions at different speeds, sound uncannily realistic especially in stereo!
I ran it into the front of my amp & also into my stereo line effects mixer post Hotplate running it parallel with my dry sound.

Now a real leslie has many factors that make it sound so wonderful, like the room reflections & the infamous doppler effect, that to simulate all those factors would be a feat worthy of the nobel prize.
The Boss sounds very close.
The reason I find that is sounds so good is that when run in stereo, it doesn't have that fake drastic stereo spread like some other simulators have, it sounds like a leslie in a room, just short of the magic that comes with with the sound of the a leslie with all the room reflections & doppler effects the come with the real thing.

One thing that really makes me happy with this pedal is, even when the overdrive effect is off, it still gives me a nice dark bluesy growl to my tone.
What I do if I don't want the roto effect is just use the brake function, this stops the rotor & horn in a fixed position, but the growly EQ sound remains.
It sounds sort of like that Robin Trower "Bridges Sighs" growl or Billy Gibbons type tone where it darkens the tone slightly.

I had the H&K tube rotosphere, I didn't like the way it colored my sound when on, made it muddy sounding, & the stereo spread didn't sound realistic IMHO..
The Arion SCH-1 chorus is cool for Fender vibratone simulation & univibe type sounds, but lacked the ramp up & down effect, it darkens the tone if desired too but not as nice as the Boss unit.
The Boss sounds very cool for guitar as long as you don't use the overdrive, at least it sounded bad on my rig, it didn't sound as bad with an organ but still I think my Digitech Bad Monkey sounds better for leslie type overdrive even with an organ sound.

I havn't had the chance to try it with my Hammond C3 or M3 yet, but I've heard it with a friend's Farfisa & I'm compelled to say that if it sounds that good with a portable, then it should sound quite stellar with a console tone wheel organ.

I am giving this pedal a 9 for sound, but if I give a real Leslie 147 a 10,,,, what does that tell you?!

I have just got this pedal so I can't comment, but as with all Boss pedals I've had before, they are very reliable.

Havn't tried.

This pedal is a blues players dream, getting that leslie sound in a nice porable package, getting that nice growl to the tone as well.
I play blues & medium to very hard rock, & I find this pedal to be a very cool addition to my effects chain.

I would buy it again if lost or stolen.
I highly reccomend it if you are in the market for a leslie simulator, try this pedal before you buy anything eles.