Boss shrinks its RT-20 to make a new absolute classic Compact RT-2 Rotary Ensemble - THE perfect Rotary Speaker Emulator as far as I'm concerned

Jul 17, 202508:00 by

Stefan Karlsson

BossModulationRotary Speaker

Boss’s larger and now long since discontinued dual-foot-pad RT-20 was a well-loved bona fide classic - with that incredibly visual circulating LED display. That larger pedal was many players’ favourite Leslie / Rotary Speaker Effect. And Boss has now brought that effect back - and better and more practical than ever - and with all the essentials in tow - including a brilliant versions of the circulating LED display!

Readers will know that I’ve long been seeking the perfect Leslie / Rotary Speaker effect - something which properly sounds like that Hammond barrel organ - with that beautifully percolating output. I’ve long sought a fuller flavour unit, and never really been fully satisfied with the output of any of the existing ones. The latest Strymon Lex is decent, and I always loved the Tech 21 NYC Roto Choir - but neither of those is wholly perfect for me. I had hoped that that the Keeley Rotary / I Get Around variant would be the right one for me - as the Brett Kingman demo sounded excellent. But that pedal is flawed - with a massive volume drop when engaged! That pedal of mine is currently with my good friend Hello Sailor Joe - where I’ve asked him to modify said pedal for an increased output.

In the meantime Boss has pulled a total blinder as the saying goes. Boss has a superb track record with Modulation Pedals with several of the best variants in the key categories. And this new version of Rotary Ensemble is wholly magnificent and absolutely perfect for my preferences and sensibilities - delivering everything I need from a Rotary Speaker Effect. The only missing element per se is the ’Brake’ function you get on some of those kinds of units - while I don’t really use that much - and there are other pedals that can give you the specific functional effect. The new Boss RT-2 Rotary Ensemble is a total Triumph for me - and I’ve not been as excited for a specific Boss pedal for quite some time! UPDATE - as covered further below - you do have the ability to engage a Brake effect via a remote footswitch.

This RT-2 performs wholly beautifully for me - it delivers that fuller more syrupy flavour - with enormous range and versatility.

Boss has done some superb engineering work on this unit - which tackles some of my earlier criticisms of certain Boss Pedals. The Control Topology here is wholly perfect - with the perfect complement of controls :

7 Controls - Level | Drive [Balance], Fast | Slow, Mode : I / II / III, Rise/Fall Time : Slow / Fast, Drive Knob Function : Drive / Horn to Drum Balance (EQ), Press-Hold Footswitch to flip between Slow [5 seconds] and Fast [instant] Speeds.

Ports : CTRL Speed, Input A [Mono], Input B, Output A [Mono], Output B.

And you have magnificent new low-profile custom Dual-Concentric knobs - quite different to the ones used on the JB-2 Angry Driver. They are much more in line with the classic silver-top Boss knobs.

The innovations here - include that really cool LED display which is achieved by having a large sequential array of Blue and Magenta LED's which beautifully reflect the relative speeds of the Horn and Drum component of the Leslie.

For the first time we have Two Options switches on the back of the unit - one to set the Ramp Speed Slow or Fast. Slow is around 5 seconds, and Fast is pretty much instant. You can also select the function of the Drive Knob - which is default Drive, but can be switched to 'Balance' which is a kind of EQ where you balanced the Lows of the Drum with the Highs of the Horn as such.

The other major innovation is that we now have a 3-way Mode Toggle - where previously and on the Waza Craft pedals etc. that toggle has been binary up to now - and typically Stock / Custom.

These are the 3 Rotary Modes :

Mode i] - The sound of the standard setting of a Leslie 122. This is the most typical of the three modes, and can be used for a wide range of instruments. Has a little more low-end Drum by default in terms of Balance.
Mode ii] - An enhancement of Mode i], but adjusted for a wider range. When combined with other distortion effect units, a natural sense of spaciousness can be obtained. Sounds a little more focused and more mid-rangy than Mode i]. [My Favourite Mode i]
Mode iii] - A new dimension of Rotary sound that combines a strong sense of rotation and deeper
distortion. Compared to other modes, the attack feel, sonic definition and the amount of distortion are
emphasized, offering greater presence in an ensemble setting.

With each of those modes you get a slightly different balance and EQ - the first mode is a little more Low-end accentuated, the second a little more midsy, and the third a little brighter. I typically like Mode ii] the best, while I'm also on Mode i] quite a bit - but need to adjust the Balance for each mode really for optimal output. I tend to have the Balance at around 11 o'clock for Mode ii], while for Mode i] you get quite a lot of low-end and therefore lean more into the Horn brightness.

The firs two Modes are brilliant for me - I've not yet really gelled with the 3rd Mode - but they're all useful.

You also have 4 Pedal Switch Modes :

Type 1 [Effect On/Off Priority] - Bypass / Engage, and Press-Hold for Slow-Fast Ramping
Type 2 [Slow/Fast Priority] - Effect is default on - and you use the footswitch to primarily ramp up and down between speeds - versus Press-Holding as for Type 1
Type 3 [Effect On/Off Priority : Slow] - Defaults to Slow Mode, otherwise as Type 1
Type 4 [Effect On/Off Priority : Fast] - Defaults to Fast Mode, otherwise as per Type 1

As mentioned - I favour Mode ii] - where my preferred settings are Level @ Max, Drive @ Max, Balance @ 10-11 o'c, Fast @ Noon, Slow @ 9 o.c, Slow Ramping - which is around 5 seconds in duration.

I can't quite put into words how enamoured I am by this pedal - it totally deliver the perfect Rotary sound for me - I found everything else out there just a little too anaemic - this delivers that full proper Hammond syrupy sound - and the sort of doppler effect across the Stereo spectrum is utterly superb.

For me this blows every other Rotary pedal out of the water - it's also one of the easiest Boss pedals to deploy - and there are no real power-up niggles like say on the SL-2. For me the Boss engineers have done everything spot on here.

Some of the purists may bemoan the lack of a 'Brake' function - but for me - this is just the most perfect rendering of this effect. I have not a single critique here! UPDATE! actually there is a way to access the Brake function via attaching an FS-6 remote switch - you can then set the control mode as either being Fast/Slow, or engaging the Brake - which is useful for synth players in particular. Like I said - I don't miss it, and don't feel I need to add the further footswitch to accomplish that. But those that need to can!

And it's also a gorgeous shade of Sparkly Soft Gold.

If you love the Rotary Speaker Effect - then this one is a must-have. It's already in my hall of fame - as per the above visual. And this augurs well for the possibility of Waza Craft PN-2W Tremolo/Pan - hopefully that one is now more likely to happen!

This RT-2 is such a great proposition - and well priced too @ $219 / €269 / £233 and equivalent. I expect these to do extremely well and be sold out everywhere at International dealers real soon!