EHX B9 Organ Machine

Started by A2theT, June 20, 2014, 03:36:09 PM

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A2theT

Really cool, so thought I'd share if you havent seen it already.   Some great stuff in this demo.

HEAVY on the METAL
Axe-Fx II, Roland VG-99 + FC-300, Roland GR-55, Digitech Jamman Stereo, Ibanez/ESP/Jackson Guitars

Bill Ruppert

#1
Thanks!
It really is a hip little pedal.
I was lucky to not only do the video demo but program the DSP.

sixeight

#2
Cool Bill. Excellent unit and demo. So we can all buy a boxed up version of you.  ;D
All it lacks is a Midi out, so you could program my VG99 as well...

aliensporebomb

#3
Great demo - the "obvious" organ sounds are all there but there were some slick ones too - that last bit with the almost twelve string + organ effect - sessions guys in the seventies would have died for that capability. 

Can you imagine two amps in stereo?  Slick.  Also, I have a sweet spot for the percussive "green eyed lady" bits, that never got old to me.

The Jon Lord and Procol Harum bits were cool too - really nice convincing fingerings.

Bill, what is that interesting guitar that looks like a neck with no body - talk about compact!
My music projects online at http://www.aliensporebomb.com/

GK Devices:  Roland VG-99, Boss GP-10, Boss SY-1000.

Elantric

#4
QuoteBill, what is that interesting guitar that looks like a neck with no body - talk about compact!

Ministar

https://www.vguitarforums.com/smf/index.php?topic=9504.msg68333#msg68333


PD FX

#5
Yes, very, very cool MR. Ruppert!  10 points from me!
Which DSP did you use?   Did you apply a FFT bin resynthesis after a bin modification or does it function via IR-like strategy?
I often play a doubleneck, 2 necks same tuning, my guess is, that it would work also with that :)


mbenigni

#6
QuoteI was lucky to not only do the video demo but program the DSP.

Jesus this is brilliant.  So impressed... again.

One question: does the mod section affect the guitar path at all?  I.e. can you turn up dry and mod, turn down organ and click, and use the pedal as a tremolo in a pinch?  I'm probably going to want one of these eventually - it would be nice if I could get another pedal off my board in the process.

This looks like a much easier way to get consistently authentic tones vs. a HOG, which will give you enough rope to hang yourself.

Bill Ruppert

#7
Quote from: Guitarpolson on June 22, 2014, 04:36:55 AM
Yes, very, very cool MR. Ruppert!  10 points from me!
Which DSP did you use?   Did you apply a FFT bin resynthesis after a bin modification or does it function via IR-like strategy?
I often play a doubleneck, 2 necks same tuning, my guess is, that it would work also with that :)


Thanks! If I talk about its workings Mike Matthews would have me in cement shoes at the bottom of the Atlantic!
He does own a boat...

The software and algorithm are created by the genius David Cockerell.
David is the Leonardo Da Vinci of guitar effects.
He designed the EMS synth of Pink Floyd /Eno fame.
To work with him has been a huge life thrill for me, he like Mike is a hero of mine.

Bill Ruppert

#8
Quote from: aliensporebomb on June 21, 2014, 09:34:41 PM
Great demo - the "obvious" organ sounds are all there but there were some slick ones too - that last bit with the almost twelve string + organ effect - sessions guys in the seventies would have died for that capability. 

Can you imagine two amps in stereo?  Slick.  Also, I have a sweet spot for the percussive "green eyed lady" bits, that never got old to me.

The Jon Lord and Procol Harum bits were cool too - really nice convincing fingerings.

Bill, what is that interesting guitar that looks like a neck with no body - talk about compact!


Thanks Todd
The guitar is a Ministar Lestar Pro. Its their new model and my fav of all them.
I also have the super small Micostar 3/4 which I take EVERYWHERE.(fits under the seat on an air plane!) other wise both go right in the overhead.
The Lestar is one piece of hard maple and sustains as well as any guitar I have. I just love it to death.
I have recorded with it a lot!
The DO need set up when you get them, but if you do and get a good one they are gold.
The other models are ok. I have many of them.

GeePeeAxe

#9
Bill, Roland should pay you at least 1 million USD for programming the new VG-XXX!
I am desperately awaiting a serious VG, not only a toy.
Maybe next year we will get something better than a Boss multi-pedal with limited functions...

Cheers,
Djordje

Bill Ruppert

#10
Quote from: mbenigni on June 23, 2014, 06:31:11 AM
Jesus this is brilliant.  So impressed... again.

One question: does the mod section affect the guitar path at all?  I.e. can you turn up dry and mod, turn down organ and click, and use the pedal as a tremolo in a pinch?  I'm probably going to want one of these eventually - it would be nice if I could get another pedal off my board in the process.

This looks like a much easier way to get consistently authentic tones vs. a HOG, which will give you enough rope to hang yourself.

Thank you!
The guitar and organ are in parallel with the organ/effects so the dry guitar has no effects applied.
On the positive side this give the combo of both organ and guitar a better sound by separating
them  giving each sound its own space.

mbenigni

#11
Quote from: Bill Ruppert on June 23, 2014, 09:36:09 AM
The guitar and organ are in parallel with the organ/effects so the dry guitar has no effects applied.
On the positive side this give the combo of both organ and guitar a better sound by separating
them  giving each sound its own space.

Thanks for the quick reply, Bill.  This is pretty much as I figured, and I agree that summing in the guitar before the mod would have been a tradeoff at best - unless there were some kind of switchable routing, but that would be pretty scope-creepy for a pedal this specialized.

QuoteThanks! If I talk about its workings Mike Matthews would have me in cement shoes at the bottom of the Atlantic!
He does own a boat...

Ha!

QuoteThe software and algorithm are created by the genius David Cockerell.
David is the Leonardo Da Vinci of guitar effects.
He designed the EMS synth of Pink Floyd /Eno fame.
To work with him has been a huge life thrill for me, he like Mike is a hero of mine.

Well deserved.  Add yourself to that list of heroes.

Elantric

#12
QuoteThe software and algorithm are created by the genius David Cockerell.
David is the Leonardo Da Vinci of guitar effects.
He designed the EMS synth of Pink Floyd /Eno fame.
To work with him has been a huge life thrill for me, he like Mike is a hero of mine.

Its a great view from above when you are Standing on the shoulders of Giants -

Congratulations on this and all future efforts Bill! 

aliensporebomb

#13
Glad Cockerell is still involved in the music FX biz - he's been involved with a lot of classic gear.

Cool.

That guitar looks like it would be great for traveling!
My music projects online at http://www.aliensporebomb.com/

GK Devices:  Roland VG-99, Boss GP-10, Boss SY-1000.

Elantric

#14
http://valhalladsp.wordpress.com/2009/05/20/electronic-music-tech-hero-david-cockerell/

Electronic Music Tech Hero: David Cockerell

I was following a discussion on Chris Randall's blog about vocoders, and the Electro-Harmonix Voice Box came up. This is a simply incredible sounding vocoder, and is "designed by the same EMS genius who made vocoding famous," according to the EHX web site. The "EMS genius" is the mighty David Cockerell.

David Cockerell designed the EMS products* from 1969 to 1972, including the VCS3, the VCS4, the Synthi-100 (famous as the BBC Radiophonic Workshop's "Delaware"), the Synthi/AKS, and the Hi-Fli pedal.  Cockerell then went on to design some of the classic Electro-Harmonix pedals of the 1970?s: Small Stone, 16-Second Digital Delay, the Microsynth, and so on. In the 1980?s, Cockerell designed the Akai samplers, including the S900. Today, David Cockerell is back at Electro-Harmonix, cranking out pedals such as the HOG/POG/MicroPog, the Stereo Memory Man with Hazari, the 2880 loop sampler, and the Voice Box.




David Cockerell
Interview Date: May 12, 2008
Job Title: Inventor
Tags:
Electro-Harmonix
electronic music
guitar effects
Keyboards-Sound Synthesis
product engineers
synthesizers

David Cockerell designed one of the earliest synthesizers produced in the United Kingdom. The Synthi was introduced in the late 1960s by EMS Ltd. The unit, which came in a case with a KS keyboard, used patch cords to root reverb and ring modes. David also included two oscillators both with shape and level controllers as well as a frequency control. The design marked the beginning of many contributions to the industry over the years including his work on guitar effects pedals for Mike Matthews in the 1980s.



Watch the David Cockerell interview here:

http://www.namm.org/library/oral-history/david-cockerell

Elantric

#15
Bill,

Your EHX B9 product is going viral


http://www.gizmag.com/electro-harmonix-b9-organ-machine/32650/

New York's EHX (electro-harmonix) has designed an effects pedal that allows guitarists to dial in classic tonewheel and combo organ sounds from the 1960s and 70s without having to worry about trudging through multiple MIDI parameters or having to route a signal through a special synth pickup to a computer before it gets to the amp. The B9 Organ Machine offers nine presets with either chorus, tremolo or vibrato effects, a percussive "key" click control and knobs to determine the mix of dry signal and organ preset at the output jack.

The B9 uses the electric or bass guitar's output signal to produce the sound of the chosen organ preset, with EHX reporting that the tracking is flawless. A nine-position white knob to the right of the stomp's logo is used to select a classic organ tone. Four black knobs sit above.

The Dry control is used to blend in the dry instrument signal at the Organ output jack to fatten up your tone or have a rich harmonic backdrop accompany your picking. Its neighbor sets the organ sound volume level. These knobs determine the mix at the Organ jack. EHX has also included a Dry output jack, which caters for signals to be routed to different amps.

The Mod knob controls the speed of the modulation effect that accompanies each preset, while the Click has been designed to simulate the percussive attack on organs like the iconic Hammond B3, though for a few presets this knob controls specific parameters. "For maximum authenticity, the click is added to the very first note or chord played and only retriggers when current notes have been released and their amplitude falls below a threshold," explains EHX.

The footswitch toggles between effect mode and buffered bypass, which will help maintain signal level and quality in both effect and bypass mode.

The Mod dial controls a chorus effect for the first six presets. Position number one is given over to an organ simulation called Fat & Full which adds an extra octave above and below the guitar sound to fill out the tone. The Jazz preset is said to be reminiscent of the sound of Jimmy Smith, and appears to be a good fit for some Green Onions love, as you can see in the video at the end.

If you're looking for a Reverend Cleophus vibe to open a soulful blues belter, Gospel is the preset for you. The Classic Rock preset is described as just a little dirty, and is said to call upon the tones of Procol Harum's Whiter Shade of Pale for inspiration.

As the name suggests, the Bottom End preset is used to add a lower drawbar sound to a guitar's sound. Octaves adds an extra octave tone to the proceedings, with the Click control used to dial in higher harmonics. Cathedral should help you to get your Dr Phibes groove on, the Mod knob for this preset is a tremolo effect, and the Click control is used to adjust its depth.

The Vox Connie is one of my favorite keyboard sounds from the 60s, and probably the best looking combo organ ever. It provides the canvas for Alan Price's key-thumping mastery in the House of the Rising Sun by The Animals, the wonderful melodic backdrop for Jim Morrison's smoldering vocals on Light My Fire, and a somewhat familiar riff for (We ain't got) Nothin' Yet from Ralph Scala of the Blues Magoos. The Continental preset brings it all back in style, and sports a vibrato modulation effect, with the Click control used to alter the depth.

The last of the nine is the Bell Organ preset, which combines an organ sound with that of an electric piano. The Mod knob controls a tremolo effect and the Click adjusts the amount of "bell" that's added to the sound.

The B9 Organ Machine comes supplied with a proprietary 9.6DC-200BI power supply and carries a list price of US$293.73, though the street price will likely be lower.

The video below shows the stomp in action.

Product page: EHX B9


http://www.ehx.com/products/b9

alexmcginness

VG-88V2, GR-50, GR-55, 4 X VG-99s,2 X FC-300,  2 X GP-10 AXON AX 100 MKII, FISHMAN TRIPLE PLAY,MIDX-10, MIDX-20, AVID 11 RACK, BEHRINGER FCB 1010, LIVID GUITAR WING, ROLAND US-20, 3 X GUYATONE TO-2. MARSHALL BLUESBREAKER, SERBIAN ELIMINATOR AMP. GR-33.

mbenigni

Got mine over the weekend.  Amazing!!!

Elantric



(Tracking demonstration)
B9 Organ Machine Played with a Banana.
Guitar straight into the B9 and played with a pick.

mbenigni

Ha - any monkey can do it!

jayson

Nice!  Banana's through a toaster!   ;D

Cheers,

jayson

Elantric

http://www.harmonycentral.com/expert-reviews/electro-harmonix-b9

By Phil O'Keefe | August 21, 2014
Organ Machine effect pedal for guitar, bass and keyboards

By Phil O'Keefe


Guitarists can be rather weird sometimes. For example, consider our fascination with (some would say jealousy of) the sounds keyboardists can generate with electronic organs and rotary speakers. Univibes, phasers, rotary speaker emulators - all were developed in an attempt to give guitarists the swirly, phase-shifted tones that organists have used for decades. There's also a variety of octave generator pedals (such as the EHX POG2 and Micro POG) that can give guitarists more organ-like sounds, but short of using a guitar synth, nothing has really nailed the basic sound of an organ well enough to fool anyone who is really playing attention.

Electro-Harmonix claims that their new B9 Organ Machine actually does give guitar players the ability to convincingly sound like an electric organ. Let's take a look and see if their claims hold up to our testing.



What You Need To Know

The B9 Organ Machine has nine preset organ sounds, with basic yet descriptive names for each one listed on the front panel.
The B9 is housed in a die cast enclosure that measures roughly 3.5" W x 4.5" D x 2 1/8" H, including the knobs. The input jack is mounted on one side of the pedal, and two output jacks are located on the opposite side.
One output is labeled "Dry", and outputs the buffered dry guitar sound at all times, regardless of whether the pedal is activated or not. Think of this as a useful aux output. The second, or primary output is labeled "Organ." What comes out of this jack depends on how you have the B9's Dry and Organ Volume knobs set, and whether the effect is bypassed or not.
The B9 has a total of five knobs: Dry and Organ Volume controls, a Preset select knob, as well as Mod and Click controls.
The Dry Volume knob controls the amount of unprocessed guitar signal you'll hear coming out of the Organ output jack. Unity gain on this knob is when it's turned up all the way.
The Organ Volume knob controls the amount of organ sound in the mix at the Organ output. Unlike the Dry Volume knob, it's possible for the organ signal to be considerably louder than your dry, unprocessed guitar signal, so in order to get equal amounts of guitar and organ (if that's what you want), you'll need to keep this knob set fairly low.
For the best sound processing and amplifying flexibility, routing the organ and guitar signals to separate effects and amps is the way to go.
Dialing up a preset is as easy as turning the white knob to the desired preset number. A wide range of different organ sounds is provided, including several B-type sounds, a cathedral / pipe organ sound, an electronic "Continental" combo organ, and a "Bell Organ", which is somewhat similar to a cross between an organ and electric piano in tone. While some of the sounds are subjectively better than others, most are very good indeed.
The Mod control adds a bit of modulation to the signal, and the modulation type (chorus-like rotating speaker, vibrato or tremolo) is different depending on which preset is selected. With this knobs turned down all the way, the modulation is bypassed. Turning it up brings the modulation in, and the knob then controls the speed of the modulation.
The Click knob also serves multiple purposes, depending on which preset is chosen. With most presets it adds percussive key click to note attacks, but on some presets (Cathedral and Continental), it instead serves as a depth control for the tremolo or vibrato, and with the Bell Organ preset, it sets the amount of Bell or chime that is added to the sound.
Tracking is terrific. There are some concerns in terms of your playing dynamics that I'll detail later, but there's no appreciable latency like you have with most guitar synths, and the B9 will faithfully (although unrealistically from an "authentic organ sounds" perspective) follow and track string bends and other guitar-centric playing techniques just fine. Glissandos, or sliding up to or down from notes, is far more effective and realistic sounding with the B9 than string bending is.
While you can play with a pick, I found that playing fingerstyle generally resulted in more realistic sounding performances since unlike strumming, it allows you to trigger multiple notes at the exact same instant, much as a keyboardist does.
Electro-Harmonix recommends using the bridge pickup for best results. Low output pickups may be an issue in some cases, and if you have problems with this, a compressor or boost pedal placed in front of the B9 to increase the signal level feeding it is the recommended solution.
With the exception of the aforementioned compressor or boost pedal, the B9 should be the first pedal in the signal path. Any distortion or overdrive you want to use with it should be placed after the B9. And yes, it sounds great with some dirt added to it, so if you're looking for those big grinding Jon Lord type organ sounds, you can definitely get them!
There are no internal switches or trim pots inside the B9, and really no need to open it up at all since there's no internal battery compartment. Power is provided by the included 9VDC adapter, and the EHX B9 uses the industry standard 2.1mm center-negative power connector. The power jack is located at the top of the pedal. Current draw is 100mA.



The B9 features buffered bypass. A red LED illuminates when the pedal is activated. Input impedance is 1MegOhm, and the output impedance is 500 Ohms for both the Dry and Organ outputs.

Limitations

You do need to be careful to play consistently in terms of picking dynamics with the B9 Organ Machine. I occasionally had notes that would "jump out" at me - usually as a result of my picking hand's "heavy thumb", and almost always when I was playing notes on the low E string. Putting a compressor pedal in front of the B9 to help even out your attack and volume makes it much easier to avoid this issue.
While the note range of the B9 is extensive, it does have some limits. Anything higher than high Eb (high E string at the 23rd fret) won't trigger organ sounds. Similarly, while you can use the B9 with an electric bass (or even a keyboard), low notes below C (A string, third fret) can be problematic, and playing below that is not recommended.
The onboard modulation is nice to have, but with relatively limited adjustability, it doesn't compete with outboard rotary sim and tremolo units. Patching in a good two speed rotary speaker simulator pedal is the way to go if you want to make the B9's organ simulation even more authentic-sounding, and you really haven't lived until you try running the B9 into a preamp and a real Leslie(™) speaker.

Conclusions

Yes, there's some caveats and limitations that you should be aware of, but make no mistake - the EHX B9 can absolutely give you classic organ sounds that are all but indistinguishable from the real thing. Yes, you have to do your part, but the sound is so similar as to be startling upon first exposure to it since it approaches the authenticity and tone of keyboard-based organ patches. Of course, the physical limitations of the guitar preclude using some of the techniques organ players typically employ, but if you think and play as much as possible like an organist instead of like a blues/rock guitarist, the sound simulation can be very convincing. In a studio environment where you can multitrack and overdub to get around some of those limitations, extremely convincing organ parts are achievable.

While you don't have the ability to dial up your own drawbar settings, EHX has provided a nice variety of basic organ sounds that are suitable for a wide range of musical genres. The onboard modulation isn't the best you'll find, but it's nice that it's included, and it can easily be turned off so you can use any of the numerous external units that are on the market. Effects are relatively easy - it's the basic organ sound that is so hard to achieve with a guitar, and it's there that the B9 excels. That is the real star here, and one that is deserving of the attention. If you want to get authentic organ sounds from your guitar, there's currently no better way short of a full-blown guitar synth to get them than the Electro-Harmonix B9 Organ Machine. 

Resources

Musician's Friend Electro-Harmonix B9 Organ Machine online catalog page ($293.73 MSRP, $220.30 "street")


http://www.ehx.com/products/b9

mbenigni

#22
I love mine!  The tones are really complex and convincing.  EHX hit a home run on this one - even the finish on the enclosure is classy.  I can't stop telling people about this pedal, even though half of me doesn't want everyone knowing about my "secret weapon".

There are a couple of things that could be improved.  These aren't complaints - especially not at this price! - but if they ever considered releasing a more expensive version down the road, more like a wish-list:

- Better filtering on the power supply.  The B9 is a little noisy if I use anything other than the power supply provided, but if I split their power supply to share with anything else, I find those devices are really noisy.
- Preset programmability - since different organ settings are best for different songs, and require different organ/dry mixes, the ability to store and recall presets would be awesome.  (I'm sometimes tempted to just buy extra B9's.)
- Improved modulation, e.g. a high-end rotary sim, and the ability to switch routing so that you can use it on your dry (guitar) signal when you need it.
- Two inputs: one that drives the organ component, and one that passes straight through to the guitar out, buffered.  Here's why (from a recent facebook discussion):

QuoteI've been meaning to get back to you on your "let's see how it integrates" comment above, which turned out to be a mouthful. The B9 itself is a bargain IMO, but I've spent significantly more money since trying to figure out how to work it into a broader guitar rig. The fundamental problem is that it, while it has two convenient outputs, it only has one input, so routing options are limited. If you need, for instance, gain on your guitar path, and a clean run from the organ to amplification, the B9's own switch becomes fairly useless. (See "Version WTF" post on my fb timeline.)

My best solution is to run the guitar out to guitar-specific effects (OD), then to the left input of a stereo pan pedal, and the organ out to the right input of that same pan pedal. The OD output has to be buffered, and all my other pedals happened to be true bypass, so I had to add yet another box for that. The two outputs of the pan pedal are run to an active A+B->Y pedal, which is subsequently run to shared effects (mod. and delay) and the amp. Alternately, you could run the organ side to its own amp/monitor.

So much for the Pedaltrain "Nano" vibe. But now I can use the pedal to crossfade from guitar to organ for "hits", or kill the organ (via the B9 switch), throw the pan pedal into volume mode, and use it as an old fashioned guitar volume pedal. I just wish I could find a stereo vol/pan pedal smaller than the Ernie Ball 6165, which has its own gravitational field.

I guess on that same topic I might add:

- An expression pedal input, for control over modulation, or - more importantly - crossfade between guitar and organ output.

mbenigni

#23
Anyone considering a B9, or anyone who already owns one but is having trouble integrating it with the rest of their rig:  you might want to consider adding an EHX Next Step Pan pedal.  Allowing for a couple of compromises, the EHX Pan has pretty much solved all my routing problems.

As I mentioned in my previous post, I was having trouble because I wanted to switch easily between clean organ and distorted guitar paths.  The best arrangement I could come up with prior to the EHX Pan involved a dedicated buffer, an Ernie Ball stereo pan, and an AB/Y switch.  The buffer and Y are active - requiring additional cables, and the Ernie Ball is, of course, massive.

The Next Step pedals are cool but a little funky. The biggest con by far is that they won't remain stationary anywhere except in the toe-down position.*  But... there just aren't a lot of alternatives for a stereo pan pedal vs. the Ernie Ball 6165, so I gave this a shot.  The first major benefit is that, being active itself, the EHX Pan is buffered on both inputs, so my buffer comes right off the pedal board.  The next major bonus is that the EHX Pan will automatically blend to one output if only one output is connected.  Off goes the AB/Y.  And the third benefit, which I didn't foresee, is that the sweep is tuned a bit better so that in the middle, you get more of both signals (whereas the Ernie Ball attenuates heavily mid-sweep.)

The only compromise is that I now get B9 tone on heel-down, where I would have preferred it on toe-down, but that was easy to get used to.  And since the pedal won't remain heel-down without my foot on it, it's very tricky to start a loop (stepping on my looper) comprised first of organ.  But overall, PSA re: another cool pedal from EHX.  It's worth noting that the Pan is the same price as the Volume and Expression pedals in the same line, and with a few small caveats, it can be repurposed as a volume and expression pedal in its own right.  Good value if you can deal with the no-park limitation.


*I just had a crazy idea that might help with this: a small amount of Velcro on the bottom of the pedal's "heel", so that you can park it in the heel-down position when needed.  Simple enough - why wouldn't it work?

Elantric

#24
http://www.jhspedals.com/products/mod-shop/electro-harmonix-b9-expression-mods/

Electro Harmonix B9 Expression Mods








The B9 from Electro Harmonix is a great organ emulator for guitar and we take it one step farther giving you fine-tune control over the B9's on-board "Mod" knob by use of an external expression pedal or an extra on-board expression knob.  The B9's Mod knob controls the speed of chorus/vibrato across all the various B9 modes....this is what you would consider the rotary speaker effect and vibe'y type sounds of organs.  By controlling the B9's Mod knob through expression, you can fine-tune your organ modulation on-the-fly and hands-free, just like you would a real organ.

After the Mod is complete, the red "Mod" knob on the B9 pedal will also allow you to set the limit on the maximum heel-down slow speed.  Turn the red Mod knob all the way to the left and you will have maximum spectrum of modulation speed when using the Expression Knob or external expression pedal.  As you rotate the red Mod knob to the right, you limit the slowest setting of available Mod knob.

Here are the Mod options:

Add on-board Expression Knob:
This option we install an oversized onboard expression knob to the side of the pedal enclosure allowing you to control the B9's Mod knob on-the-fly by using your foot to roll the expression knob.  Rolling the on-board expression knob will change the speed of the B9's chorus/vibrato.

Add Expression Jack:
This option allows you to plug in an expression pedal such as the M-Audio EX-P and control the B9's Modulation knob on-the-fly by use of the expression pedal.  Using an expression pedal changes the speed of the B9's chorus/vibrato.



http://www.jhspedals.com/products/mod-shop