Boss RT-20 Rotary Speaker Simulator

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.