Boss RT-20 Rotary Speaker Simulator

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.

Very easy to use. All knobs at 12' seem to be perfect (except overdrive).
The manual is ok.

I use this unit as a virtual hammond-leslie (that's what it's mainly built for), not as an further effect for their guitar like a some of the other guys in this review. I have a Voce V5. In my opinion on of the best hammond clones on the market. I also own a Hammons M-101 and the real thing, a leslie 145.

It's not noisy at all.

The four different sound settings are obviously, for me, no. 1 is the most convincing and useable.

The leslie effect is incredible. I have also a H&K Rotosphere and compared it not only via headphones but also during a session with my band.

My results:

the Rotosphere sounds great when overdriven (it has a real tube)and in slow". When turned to "fast", it get's a bit cheesy and definitely doesn't sound as the real thing (as I wrote above, a own a 145)!

The RT-20 has generally a different sound character and has not that extreme left-right separation (which is, played over a PA, a plus in my opinion). Slow is great, fast is even greater. You can almost hear the growling and the sizzling of the horns. The two different loudspeakers are very convincing in terms of the separation, acceleration, velocity, etc. Similar to the built in leslie in the VK-8.

The overdrive is, on the other hand, a disappointment. It begins that when you turn the knob just a bit to the right, it's already to much. There's also an annoying change in sound colour, when on (even before you actually hear a distortion). I played the Voce with a volume pedal but I wasn't able to get a convincing amount of overdrive unless it produces that mashed, mutty sound. Try the Rotosphere and you will hear the real tube overdrive. It really screams, when played high, overdriven tones. The RT-20 weeps...
So once again: digital cannot totally reproduce an analog overdriven tube. The guys from H&K know this.

I would have given a 10, if there wasn't that weak overdrive.

Seems to work forever. Only the unnecessary "lightshow" with all these LEDs, which marks the velocity of the two horns may brake one day.

-

I play keyboards over 20 years. In former days I played hardrock, since 5 years I also play in a soul and funk band, so for me the most important sounds are the classics: piano, Rhodes, Wurli, Clavinet and Hammond. Sometimes some strings and brass sounds.

For the first four, I have my Yamaha P-120, for the Hammond the Voce and now the RT-20. ( used to use the 60s&70s expansion card of my Roland XP-30, but it's nothing compared to the sound, handling and the "real" drawbars of the Voce). For the rest my XP-30.


The dilemma: I will definitely play the RT-20 and give the Rotosphere away. But I need an additional tube overdrive. Maybe, I try the Tube Factor from H&K or the Speakeasy Vintage Tube.

I'm very curious, if somebody has experience concerning tube preamps for organs.

Things won't get easier...

Thanks for reading.

This is my first (preliminary) review of the device--I hope to add it to my own arsenal, but only after trying it with my rig (sometimes a pedal will sound great in the store with a borrowed guitar & amp, but not respond well and go to crap with your own rig--in my own case, the Boss CS3 did that).

Having said that, this thing's pretty dang good-MUCH better than the Line6 stompbox (too shrill, brittle and digital-sounding), the H&K Rotosphere (too noisy, too expensive, too noisy, too brittle and did I mention too noisy?) the Electro-Harmonix Wiggler (just too "ehhh, vanilla-boring"-sounding for an effect that's supposed to be very dynamic), the Peavey Delta Stomp (the best of the rejects, but just a hair too digital-sounding, and prone to vanilla) the Digitech Eric Clapton Crossroads "Badge" setting (I really wanted that one to work--the tone was there but it was just too dang noisy) and the Dunlop RotoVibe (it just doesn't sound like a real Leslie). Screw the Uni-Vibe--it's a cool effect, but it's not a true Leslie simulator effect; it's its own thing. I have obviously been looking for a good Leslie effect for quite a while, and tried many things...so far, this one takes first prize.

The knobs, with the exception of the "Settings 1-4" knob were all self-explanatory, and that one exception wasn't a problem. Just tweak until you get the sound you want, and it was good. If I remember correctly, settings 1 & 2, slightly heavier on the drum and lighter on the horn were my favorites.

I purposely used a slightly bright guitar with single coils (more prone to noise) through a "cold-sounding" transister amp, due to the fact that many/most of the Leslie effects I've tried have been too bright, brittle, shrill and/or NOISY (sounds like my wife's cousin!).
Plus, I am using single coil-equipped guitars 98% of the time (Telecaster, Stratocaster, & a lipstick-loaded Danelectro), so it would give me a somewhat accurate rendering of what I want to know.

I think so many effects manufacturers are trying to get every nuance of a real Leslie and start allowing/ignoring the excessive noise that can occur with a real Leslie; this would not be a problem except the fact that other pedals in the signal chain, the amp, the guitar, etc. will also add small amounts of noise--it all adds up to a big humming mess, especially when recording.

Having said that, the RT20 was VERY quiet, even without any kind of noise suppression (I use a Rocktron Hush pedal at the end of my signal chain). My favorite way to test how noisy any pedal will be is to find a setting I like, then put my ear near the amp and damp the strings--just listen to the amount of hum generated by normal room interferences (fluorescent lights, other amps, etc.); then I let go of the strings and listen again. That usually tells me a great amount about how much noise a particular effect (by itself) adds.

The tone was warm (!) and tube-y sounding (even through the bright little transistor amp I was using at the store), with little or no digital brittleness, even with the horn setting cranked. It did a pretty good Jimmie Vaughan "Tip On In" tone, SRV "Cold Shot" sound, and the sound I was looking for on my own compositions, "Travis County Line" and "Monkey Hips".

The final test will be when I try the effect through my own rig and also with my harmonica (I run the harp through my effects, and on certain songs, I will use the harp through a Leslie effect to get a Hammond-y sound).

I have a couple of Boss pedals, and they've never gone out on me.

Their main website was pretty useless (mainly a sales propaganda site), but there was a secondary site that was more technical, and it was very helpful in figuring out that the 1-4 settings were supposed to be, and etc.

I've never contacted the OEM directly, so I'll give them a 7.

I play Texas Roadhouse music--mix uneven amounts of Blues, Rock and Outlaw Country--in the Screamin' Armadillos. Someone described us as early Fabulous Thunderbirds touring with ZZ Top and Waylon Jennings (I took that as a compliment). This type of music begs for some Leslie-effected guitar.

What I have done as a stop-gap measure in the meantime is dimed out the speed control on my MXR Phase 90, then turned it slower/back about 3/8 of an inch--with some medium overdrive BEFORE the phase shifter, you'll get a fairly good, airy Leslie effect--not too brittle or noisy...it's the best I have been able to find to fit with the dynamics of my picking style, etc.

I play guitar, slide guitar, harp and vocals. I already compared it to other similar effects above, and this one seems to be the best of the lot so far...I really want this to be "the ONE"...I'm tired of looking, but I won't settle for something sub-par. If the RT20 sounds as good the next time as it did the first time, we've got a winner!

As a complete side-note, I loved the little LED spinning speaker visual effect--that was really cool.

My rig is as follows: Ibanez TS9(ReIssue) Tubescreamer, 70's block-logo MXR Phase 90, Crybaby Wah, Boss DS1, Jim Dunlop Jimi Hendrix JH2S Classic Fuzz, Danelectro Daddy-O, DOD 7-band EQ, Rocktron Hush pedal, all into a 1963 Reissue Fender Vibroverb (the one with brown Tolex and 2 ten-inch speakers).

I use a 1940's Astatic microphone for harp work, and play a US-made 1962RI Stratocaster, a classicly styled hecho-en-Mexico Telecaster and a Danelectro DC3. There will soon be a P90 equipped axe in the arsenal.

A piece of cake for any gear heads who know their way around signal processing gear. For all others a reading of the manuel should answer any questions. Unlike other companies, Boss manuels are reasonably well written.

I play keys and guitar. With a Roland VK-7 organ I found that thr RT-20 was more robust, and juicier than the built in, on board Leslie simulator. And much more realistic. The fact that I was able to control the speed in realtime with a Roland EV-5 expression pedal was a real plus. On ascending chord progressions (think the pre turnaround chord progression in Stormy Monday) I was able to precisely time the increase from slow to fast so that by the time I got to the end of the progression I was at maximum speed. Without the expression pedal I used to have to toggle the speed back and forth if I found that the rate of change was too fast. Also noteworthy is that I found the onboard overdrive on the VK-7 to be warmer and more bubbly than what I was able to get out of the RT-20. For most applications I would use the overdrive on the keyboard, but I did find that the brighter more grinding overdrives on the RT-20 were great for getting a wicked grind out of low register single notes.
With guitar I was also very pleased. A Strat into the RT-20 played through a Boogie DC-5 head with a Boogie 2-12 Recto cabinet loaded with Vintage 30 's yielded the best Leslie simulation that I have ever had the pleasure to try. I had been relying on a Fulltone Deja Vibe and a Fulltone Choralflange to approximate the sound of a Leslie with unimpressive results. Both of these pedals are great, but they don't realistically capture the sound of a Leslie. The RT-20 is the real deal though. I was able to get the bubbling-shimmering sound that SRV gets on the solo to Cold Shot by combining a touch of overdrive from a Fulltone Fat Boost with the RT-20. The guitar break in Eric Clapton's Badge was also realistic enough to bring a smile to my face.
The built in overdrive sounds very much like the Fender and '59 Stack overdrives that I have in my Roland GT-6 processor. This should come as no surprise as Boss uses the same proprietary COSM technology in both devices. Personally I prefer analog produced overdrive to digital when I turn to a pedal to provide overdrive. I expect that I'll be using my various and sundry boutique overdrives when I want to combine overdrive and the Leslie effect. This isn't to say that the onboard overdrive on the RT-20 isn't any good. In certain situation it would be fine for certain songs.
On the down side, I did notice a little hi frequency noise. This gets processed and adds a helicopter like character to the overall sound. I seem to remember that real Leslies had a touch of this. At any rate it was acceptable when I adjusted the Rotor balance to what I personally found the best setting for guitar (at about 10:30).

This is my 9th Boss effect. I've never had a problem. Boss must be confident that it will last, otherwise they wouldn't offer a 5 year warranty.

Don't know. Never had to deal with Boss.

I play Blues and Rock. I've been playing for more than 40 years. I've tried several devices that attempt to duplicate the Leslie sound, and this is definitely the best yet. I know that a lot of people are going to criticise this pedal because the only indepently adjustable parameter of the rotors is the relative volume balance between the bass rotor and the treble rotor. I'm sure there are many who would like to indepently adjust the rise time and minimum and maximum speads of the rotors as well. This was indeed a concern of mine when I was considering purchasing this product. After playing through it though I can honestly say that I don't miss those features. It appears that regardless of how you set the speed and rise time, there is always a difference of speed and acceleration between the two rotors, just like a real Leslie. So even though, for example, one control affects the rise time of both rotors, they appear to accelerate and de-accelerate at slightly different rates. The operative word here is "appears". The rotors spin so quickly it's difficult to say for sure. I would be curious to hear what others have to say about this. And similarly, even though the slow speed adjust both rotors simultaneously, I still get the sense that they are spinning at slightly different speeds relative to each other. This may actually be a good thing that rate and speed are not indepently adjustble. On my VK-7 they are, and I've found that sometimes an objection "beat" results with certain combinations of speeds.

super easy
Way lighter than a real 122

headphones, direct and into a tube amp, gorgeous leslie tones, usable distortion, the rotors spin reversly to each others, like the real thing
minus one for being digital(easy to clip if the 24 bit converters are overdriven)

it's a boss double pedal, a double tank;0
the rotor disply will die before the pedal, i'm pretty shure

it's a boss

beside the tube rotosphere MKII, one of the best emu IMHO

Extremley easy to get a good sound. The important variables, i.e the nobs that are most key are notched at the 12 O'clock position so that you can point everything at 12 and have a great standard sound for a slow and fast leslie.

To pedals (part of the boss twin series) left = on/off right = fast/slow. Holding both down at once activates the breaking function - just like a real leslie would do.

No pathces, just the four different leslie models.

The manual is vrey thourough, and really explains everything very well. Athough it really doesn't need to, it's extremley self explanetory.

I've been through just about EVERY type of leslie effect short of getting an acutal rotating cab. It's my favourite modulation sound and integral to a couple of tunes off of my solo record. Up to now I haven't found one that is convincing. (On my record I used a virtual moddled leslie plug-in in pro-tools) I've tried all the various Line 6 ones, the Rocky Road, the H&K Rotosphere (which was the closest/best till now!)

I believe i've finally found the one in the boss rt-20. It fulfils all the featuer requirements I needed and also sounds fantastic, and is a lot smaller than the H&K.

I'm using this with;

Ibanez 152-7 string, Ibanez RG770 and a Japanese Strat in to --> BH1 Wah, Fulldrive 2, THIS PEDAL, Mesa Boogie Nomad 100 Amp -->FX Send Line 6 Echo Park -->RX Return.

Very quiet when on, and also excellent buffered bypass like the usual boss stuff.

Out of the 4 models on offer the first is the best and one that will see the most use. The standard 122 leslie model. Mode 2 is the same but more tremolo emphasized a bit more volume pulsing. Whils the 3rd mode is not very convincing and the 4th is a very "meh" Uni-Vibe model, which is only just useable and I dont think I will be. Too lumpy and notchy. But I bought this for its leslie sounds and boy are they amazing!

Its very warm, obviously it spins your head off, and not sterile like the L6 stuff. Sounds as good as the H&K but I find this quieter. The L6 rotomachine in particular was terrible :( I wanted to like it cause it was so cheap, but it definatley changed the signal tone even when off, and when on it was very harsh and didnt feel part of the overall tone.

The boss has an effect mix dial as well as a dry signal dial and you can get a great mix, and balance with your dry tone/off tone. Or if you prefer set it to boost in volume when turned on.

You can also set the balance between the bass rotor and the horn rotor, as well as setitng fast slow settings and changing the time it takes to ramp up or down to the fast/slow settings.

Holding both the pedals breaks/accelerates using the time setting of the aforementioned ramp dial. This is very cool.

Kind of pointless but very cool is the virtual light display showing the rotors. Cool and dorky at the same time, this definatley stands out on the pedal board.

Being true stereo you can also put an organ/keys through it and it even has a bias setting to optimize for either guitar or keys.

The only really poor thing about this pedal is the overdrive, whilst COSM modelling clearly has nailed the leslie effect the overdrive is only ok. For just a bit of crunch it is sweet but anything past 9 oclock and its very harsh. However sounds fantatic for crunching up and rotating organ though.

I use overdrive from a Fulldrive 2 though, or my mesa boogie so, again I dont need the OD, as mentioned I bought this purely for it's rotating abilities.

It will easily cop SRV (Cold Shot) Breaking Benjamin (So Cold), umm and many more. But most of what i use it for is on my original stuff.

It gets a 9 for sound cause 10 would be an actual leslie.

I've not much experience with the twin pedal series but no reason to think this will be any different to the usual boss sturdyness.

n/a

My solo/band record is modern rock/pop and contains some lead breaks and arps that have a bit of rotary on. Pretty distinctive really and and non-musos recognise when I'm giggin without a rotary on the board.

Been playing 12 years, other gear listed above.

Most definatley get another one if anyhting happened to it.

I love that its warm, and yet transparent, well swirly :). Dont like the onboard OD. It's also sounds great in the loop. Cant decide where to keep it yet.

Compared it to MANY been searching for the ultimate leslie for a whlie. I believe this is it so far! Hmm not really, maybe presets switching but you really dont need it. Two speeds, on/off and the break. Voila.

If you need a leslie effect then this and the H&K rotosphere are the only real contenders. And seing as you can buy TWO of these for the cost of 1 rotoshpere and that the footprint is damned sight smaller, its a no brainer.

Also, its a real nice effect if you're tired of chorus/phase and flange. You can set it slow and subtle and it can bring a nice swirlying shimmer.