Designing New Effects Pedals

Stuff that alters the sound going in or out of the amp, JVM Loops, XLR Out, Line Out, Stereo setup with 2 amps, Midi

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Casey_Butt
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Designing New Effects Pedals

Post by Casey_Butt » Fri Nov 29, 2019 5:55 pm

This was continued from here: viewtopic.php?f=1&t=11322
okgb wrote:
Thu Nov 07, 2019 8:00 pm
you've read the tale by cjones right ?
http://freestompboxes.org/viewtopic.php?f=7&t=1159

Hope it does well for you and let us know!
I've never read that before. It's an interesting story. Thanks for linking it.

That's just the tip of the iceberg, though. Even most of the very big names in the boutique industry can't seem to come up with even the most rudimentary of their own original designs. I can think of four major players whose companies produce almost exclusively clones of old pedals under different names - usually with a component or few swapped here and there and the latest trend being using digital relaying to swap different components into the old circuits.

But there's also a balance that has to be struck between new and what's expected. People expect an overdrive pedal to sound like a Tubescreamer or Boss OD, so if you stray too far from that basic formula people get put off. On the other hand, why make yet another Tubescreamer variation? IMO, if you're going to go the overdrive route the pedal has to be able to produce all the qualities of the old pedals but with more - more control over the qualities, more of the qualities in general, and less of the shortcomings. But to truly do that (not just mojo and hype) you have to know more about electronics than just how to copy someone else's schematics. You have to completely understand the functioning of the circuit and how those electronic characteristics translate to sound qualities. That's a very in-depth knowledge of three different fields - electronics, the physics/mathematics of sound waves and what's pleasing musically. Very, very few builders seem to have anything more than a basic knowledge of the first two... that's probably because they were guitarists first and not electronics engineers and physicists. They're following their passion, but they really don't have the backgrounds to deep dive into electronics design. On the other hand, very few electronics engineers are good enough musicians and know enough about the physics of sound to translate their engineering knowledge to what sounds good and behaves well to musicians. There's an awful lot of disciplines that have to come together there. Actually, Santiago, though I've only had limited contact with him personally it's still obvious, is one of the very few of those people with such an encompassing background - that's why he could design something original yet true to the classics like the JVM.

...FYI, the magic Tubescreamer requires four component swaps, not three. This is why, in that story, the Goose's OD pedal was so easily replicated by Gomer. Had the Goose only known about the fourth component he would have revolutionized the entire overdrive market.
okgb wrote:
Fri Nov 29, 2019 3:43 pm
The pedal biz? I don't get it, if you can't compete and make a " better " sounding pedal, you make one that sounds worse ?
Well, some people are just in it for the potential sales money and others love the craft. But, unfortunately, loving the craft doesn't necessarily mean you're good at it. That's why 90+% of the boutique builders are essentially limited to fuzzes, overdrives and Dyna Comp clones - they're typically simple circuits that are easy to copy.
Sounds like you're in this at ground level Casey, I would substitute the word useful for familiar, the new part of the pedal you can grow with and the familiar part use right away.
That's been sort of my approach to most of the designs. That and addressing age-old shortcomings of some staple effects. For instance, plenty of people want a Tubescreamer or SD-1 type pedal with the option for more bass, but almost every attempt to deliver that results in a loose, flubby bottom end. It's certainly do-able but doing it requires a much more in-depth design than just trying bigger coupling caps up front. The typical boutique builder who plays around with modding existing circuits typically doesn't have the electronics background to really tackle those issues. Add in expanding the design so it cleans up better yet also has as much gain on tap as a high-gain amp and can be tonally transparent on demand and you're getting into some fairly heavy electronics design. That's just an example but that sort of reworking of the classic effects is basically what set me off.

So far I've built and tested prototypes of an overdrive preamp, distortion preamp, fuzz preamp, compressor (OTA-based), optical tremolo, stereo chorus, phaser (optical), uni-vibe (with no bulb and runs on 9V), and flanger.
_ JVM410H: "Blackface" Clean channel, "Plexi" Crunch channel, "Dual Rec" OD2 channel, 3rd stage bias pot with switchable 100nF bypass cap, switchable 470k/470pF "treble peaker", OD1/2 Orange and Red extra gain pot, signal boost into power amp, PI voltage set to 2203 levels, 5H choke w/ 50uF on screens, -ve feedback pot.
_ Marshall 2203/1959 clone - switchable (with FX loop, resonance control and -ve fb pot) built from a Peavey Windsor 'donor' head
_ Fender Deluxe Reverb clone head
_ ADA MP-1, ART Power Plant, Tech 21 PSA-1
_ 1960A cab w/ Celestion G12-65s and G12-75Ts in X-pattern, Peavey JSX cab with Celestion G12M's (UK 6402 cones)
_ Fender Pro 185 (rebuilt) - open back 2x12" with Jensen C12Ks

okgb
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Re: Designing New Effects Pedals

Post by okgb » Fri Nov 29, 2019 6:54 pm

When I mod tube amps for people, I consider the caps & tone shaping to serve the fundamental sound [ & overdrive ]
Why not put an eq in the loop after the root sound is accomplished ? I say this in regards to " where to add low end "
there have been some famous people who prefer the sound of a fender style overdrive [ early eq ]
for the average guy , buy an eq , experiment, find out [ develop more taste ]

In the car market, you come up with a new model every year, for software there's fewer new features to come up with and hence the subscription model , the pedal market? mostly more people trying to cash in on the same old thing! the race for the bottom [ cost wise ] is people who don't have the conviction to back up their choices [ by actually knowing what they like ] so they can spend a small amount and feel like they're in the game without losing! A pedal with allot of digital control? why not have a rack mount multi fx that already does that?

You, I trust, but being a good muscian or having a great song these days is not enough, one has to really be a " player " [ follow the money! ]

Do all the new builders try to out do each other and not the classics? but like heavy metal [ for example ] which will always have their demographic
people want " their " stuff not their parent's or older people, for awhile ........until they figure it out!

Anyway, be sure to let us know where when we can find & try something and offer our support!
Amps JVM 410H [too many mods to mention ] '73 50w lead, 70's vibrochamp , mesa mkIII U.S. Vox pacemaker
Rock , pop rock & Blues style's mainly played
Gtr's Musicanman " Luke " wolfgang [ carved top w pearly gates ] Hondo lazer , Warmoth strat
Fx t.c. 2290 , Lexicon tc verb
Pedals tbone plexi , t.c. chorus , various handmade & usual suspects t.s. , zen , CB wah ..........

Greg_L
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Re: Designing New Effects Pedals

Post by Greg_L » Fri Nov 29, 2019 7:14 pm

I think the pedal craze has jumped the shark. People don't play guitar or amps anymore. They play pedals.
My gear list? Do a search.

okgb
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Re: Designing New Effects Pedals

Post by okgb » Fri Nov 29, 2019 7:24 pm

Yeah , I can see recreating sounds from a release, [ pity you if you're in a cover band ] but some big guys have someone doing the switching for them
although there's a certain amount " old guys don't get it " [ I don't ] as the baby boomers die out so do the classic [ good ] sounds?

Thinking about it, odd weird or interesting sounds is more " production " then music itself , I guess some will call it Art.
perhaps the successful builders will offer weed store discount coupons ?
Amps JVM 410H [too many mods to mention ] '73 50w lead, 70's vibrochamp , mesa mkIII U.S. Vox pacemaker
Rock , pop rock & Blues style's mainly played
Gtr's Musicanman " Luke " wolfgang [ carved top w pearly gates ] Hondo lazer , Warmoth strat
Fx t.c. 2290 , Lexicon tc verb
Pedals tbone plexi , t.c. chorus , various handmade & usual suspects t.s. , zen , CB wah ..........

Casey_Butt
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Re: Designing New Effects Pedals

Post by Casey_Butt » Fri Nov 29, 2019 11:33 pm

okgb wrote:
Fri Nov 29, 2019 6:54 pm
When I mod tube amps for people, I consider the caps & tone shaping to serve the fundamental sound [ & overdrive ]
Why not put an eq in the loop after the root sound is accomplished ? I say this in regards to " where to add low end "
there have been some famous people who prefer the sound of a fender style overdrive [ early eq ]
for the average guy , buy an eq , experiment, find out [ develop more taste ]
With overdrive, tuning the top and bottom ends before and after clipping are key (as you obviously already know). Typically, overdrives filter off the bottom up front to keep the sound tight... but that also tends to make the sound thin. If you trim the trebles up front you lose the high-end harmonics, which are better filtered off after... yet too much high-end clipping again thins out the note. The classic pedals all balance this out successfully in their own fixed ways but none of them really give you much control over it all.

When I designed my overdrive I made the heart of it very Tubescreamer/SD-1-ish and added a cascaded preamp section with a flatter voicing, then I added active bass boost and treble trim controls, post gain, so you can fine-tune it. With all the knobs CCW it's essentially a transparent clean boost with a tonally flat voicing. With OD up and Preamp down it's a classic OD pedal in the Ibanez/Maxon/Boss style (but with less of the clean signal blended back in), with OD down and Preamp up it's a very Fender-ish type driven sound, and with both OD and Preamp up you get basically the sound of cranked high-gain Marshall. The topology and voicing lets you get everything from a clean boost, to a fat Fender type overdrive to a high-gain metal amp, with as much bottom end as you like without losing tightness. There are also some other little features in there like "tuned" asymmetrical clipping in the OD section (which Boss pedals attempt to do but they actually don't), but that's the gist of it.

This is the graphics... assuming the screen printing comes out clearly.

Axiom Overdrive Preamp OP-1 - Copy.jpg
Axiom Overdrive Preamp OP-1 - Copy.jpg (62.9 KiB) Viewed 169 times
okgb wrote:
Fri Nov 29, 2019 6:54 pm
Do all the new builders try to out do each other and not the classics?
It seems to me the operating model of most, if not all, of the analog builders is to put their own twists on the classic effects and effects categories - a new Fuzz Face, new Dyna Comp, new Rat, new delay, etc. That's totally fine because some people might like their "twist" better than the others. What bothers me is when someone copies a pedal, changes a cap or two, renames it, pretends they've invented the ultimate pedal and charges a small fortune for it. I have no respect for those fakes. I designed pedals that I always wished I had, in part by "fixing" the pedals that I've always felt needed some improving. For instance, I always wanted the ultimate phaser - fully analog with a clean blend, control over the center of the frequency sweep and the ability to adjust the modulation from triangular to sinusoidal. I couldn't find one, so I designed one myself. I'm sure I'm not the only person looking for that phaser. Another example, the Dyna Comp is legendary but it has serious limitations. Studio compressors have a full control suite but sound sterile and lifeless when plugged into a guitar. Why doesn't someone make a compressor that can still capture the dynamics of an old Boss CS-2 but with the performance standards and features of a studio compressor as well? No one else seems to be doing it, so I had to do it myself. So my approach has been to take the best-in-class effects in each major effects category, determine the electrical characteristics that make them the best, and then redesign them from the ground up to exceed their original specifications. It's like a eugenics program for pedals. :))) ...Why even make something if you know someone else is making it better?
Greg_L wrote:
Fri Nov 29, 2019 7:14 pm
I think the pedal craze has jumped the shark. People don't play guitar or amps anymore. They play pedals.
...And looking for "pedal friendly" amps to go with them.
okgb wrote:
Fri Nov 29, 2019 7:24 pm
as the baby boomers die out so do the classic [ good ] sounds?
I hope not. I think if you design for electrical and audio performance rather than music trends or styles you'll be on the right track. For instance, I've been working on a flanger for months and my standard is getting delay times, frequency response and modulation shape that beats the legendary A/DA. How people use that tool is up them.
_ JVM410H: "Blackface" Clean channel, "Plexi" Crunch channel, "Dual Rec" OD2 channel, 3rd stage bias pot with switchable 100nF bypass cap, switchable 470k/470pF "treble peaker", OD1/2 Orange and Red extra gain pot, signal boost into power amp, PI voltage set to 2203 levels, 5H choke w/ 50uF on screens, -ve feedback pot.
_ Marshall 2203/1959 clone - switchable (with FX loop, resonance control and -ve fb pot) built from a Peavey Windsor 'donor' head
_ Fender Deluxe Reverb clone head
_ ADA MP-1, ART Power Plant, Tech 21 PSA-1
_ 1960A cab w/ Celestion G12-65s and G12-75Ts in X-pattern, Peavey JSX cab with Celestion G12M's (UK 6402 cones)
_ Fender Pro 185 (rebuilt) - open back 2x12" with Jensen C12Ks

Greg_L
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Re: Designing New Effects Pedals

Post by Greg_L » Sat Nov 30, 2019 3:16 pm

Casey_Butt wrote:
Fri Nov 29, 2019 11:33 pm

...And looking for "pedal friendly" amps to go with them.

Lol. I didn't wanna go there, but yeah. As soon as I hear someone talk about amps as being "pedal platforms" I wanna punch them in the throat.
My gear list? Do a search.

okgb
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Location: The Great White North-Winnipeg

Re: Designing New Effects Pedals

Post by okgb » Sat Nov 30, 2019 6:45 pm

Yeah when You get into the amp business, amps shouldn't " need " pedals and be gigable as they are but, nothing wrong with adding more flavor!
my great chase is getting a loud amp sound [ and feel ] with things that aren't loud amps, lively , harmonically rich but not overly distorted with good sustain, and smooth decay on the harmonics, adding a compressor helps. Attack & decay [ or total ADSR ] is necessary on comps but I can see how some manufacturers would limit control so users would stumble on more good sounds first [ have a harder time making them sound bad playing around ]

I appreciate that your amp mod posts back it up with explanation, Hope your not getting your pcb's made over seas! Do you have some protection like multi layer boards ? Jack Deville seems to do well with the hackers not getting into his stuff!

Misc. I don't know why it took the world so long to build the 1176 into a pedal, seemed a no brainer for a long time, problem with gtr comps is you need a couple presets to cover different thershold types of playing , like clean funk Vs distorted solo lines. the blend control is a good idea that came from the world of studio parallel compression. [ makes it harder to get in trouble! ]

What you describe for your phaser sounds like back in the day when they were rack mount devices, no where near as complex but I thought the MXR phase 99 , was a good update , dual mono / stereo sync options
Amps JVM 410H [too many mods to mention ] '73 50w lead, 70's vibrochamp , mesa mkIII U.S. Vox pacemaker
Rock , pop rock & Blues style's mainly played
Gtr's Musicanman " Luke " wolfgang [ carved top w pearly gates ] Hondo lazer , Warmoth strat
Fx t.c. 2290 , Lexicon tc verb
Pedals tbone plexi , t.c. chorus , various handmade & usual suspects t.s. , zen , CB wah ..........

Casey_Butt
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Posts: 1469
Joined: Mon Nov 02, 2009 7:09 pm
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Re: Designing New Effects Pedals

Post by Casey_Butt » Tue Dec 03, 2019 12:16 am

okgb wrote:
Sat Nov 30, 2019 6:45 pm
Attack & decay [ or total ADSR ] is necessary on comps but I can see how some manufacturers would limit control so users would stumble on more good sounds first [ have a harder time making them sound bad playing around ]
It can be tricky to design a compressor with independent attack and release controls. That's why I think most analog stompbox compressors don't have them. You'd need a fairly competent electronics engineer to come up with it from scratch.
okgb wrote:
Sat Nov 30, 2019 6:45 pm
Hope your not getting your pcb's made over seas! Do you have some protection like multi layer boards ? Jack Deville seems to do well with the hackers not getting into his stuff!
Other than small batch prototyping, I haven't decided on who I'll go with for the production boards. I'd prefer to keep it domestic if at all possible, but in the end I'll let quality be the deciding factor.
okgb wrote:
Sat Nov 30, 2019 6:45 pm
Misc. I don't know why it took the world so long to build the 1176 into a pedal, seemed a no brainer for a long time, problem with gtr comps is you need a couple presets to cover different thershold types of playing , like clean funk Vs distorted solo lines. the blend control is a good idea that came from the world of studio parallel compression. [ makes it harder to get in trouble! ]
It's funny you should mention that. My original motivation to get into designing pedals was a FET compressor I was working on. I heard of the Origin Cali76 not too long after that and figured, "Well, that's been done." From there I went to a feed-forward VCA design (that turned out sounding too sterile for guitar). In the end, I decided to go with an OTA style compressor but rework the classic design to include attack, release, gain, blend/ratio, threshold... essentially a compressor that reacts like a classic stompbox compressor but with the full suite of studio compressor controls. I also fixed a few of the famous potential flaws of that sort of design.

AXiom Classic Compressor CC-1 - Copy.jpg
AXiom Classic Compressor CC-1 - Copy.jpg (74.06 KiB) Viewed 110 times
What you describe for your phaser sounds like back in the day when they were rack mount devices, no where near as complex but I thought the MXR phase 99 , was a good update , dual mono / stereo sync options
You're on the money again. I was actually going to get myself a Phase 99 but thought since I was at it, why not just go all the way and design a Phase 90 type phaser with all the trimmings? I had just finished a Uni-Vibe design and decided to play with an optical phaser design because I liked how smooth and distortion-free they are. I built a bunch and distilled it all down into one. Essentially, it's like a Phase 90 with a clearer sound and much more control over the parameters. I considered going stereo but that would take up enough space on the board that I'd have to cut a few of the other options - which I didn't want to do. So I designed the phaser as a single-channel with the full host of options and designed a stereo chorus with independent channel controls for people who want stereo spread.

AXiom Phase-Vibe PV-1 - Copy.jpg
AXiom Phase-Vibe PV-1 - Copy.jpg (76.98 KiB) Viewed 110 times
AXiom Stereo Chorus-Vibrato SCV-1 - Copy.jpg
AXiom Stereo Chorus-Vibrato SCV-1 - Copy.jpg (85.38 KiB) Viewed 110 times

By the way, anyone who has any suggestions on what they'd like to see in an analog pedal (no digitial... at least for now), feel free to make them here. I'll gladly take everything into consideration.
_ JVM410H: "Blackface" Clean channel, "Plexi" Crunch channel, "Dual Rec" OD2 channel, 3rd stage bias pot with switchable 100nF bypass cap, switchable 470k/470pF "treble peaker", OD1/2 Orange and Red extra gain pot, signal boost into power amp, PI voltage set to 2203 levels, 5H choke w/ 50uF on screens, -ve feedback pot.
_ Marshall 2203/1959 clone - switchable (with FX loop, resonance control and -ve fb pot) built from a Peavey Windsor 'donor' head
_ Fender Deluxe Reverb clone head
_ ADA MP-1, ART Power Plant, Tech 21 PSA-1
_ 1960A cab w/ Celestion G12-65s and G12-75Ts in X-pattern, Peavey JSX cab with Celestion G12M's (UK 6402 cones)
_ Fender Pro 185 (rebuilt) - open back 2x12" with Jensen C12Ks

okgb
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Re: Designing New Effects Pedals

Post by okgb » Thu Dec 05, 2019 2:11 am

F-You Casey! now I gotta buy all your stuff!

I really would like to have a two preset for the comps like a rythym/lead thing, or heavy & light , but the blend or dry control makes it harder to sound bad with heavy compression
Have you heard the FMR really nice compressor ? not necessarily for gtr but it's an analog circuit with digital control,[ 3 detections methods layered ] you can really compress without sounding overdone

Phaser doesn't have to be true stereo, a dry out on a switched jack works, set up two amps one with tremelo and one without and it feels like it's panning

How does you're chorus compare to the classic tc SCF ? [ my benchmark ]
Amps JVM 410H [too many mods to mention ] '73 50w lead, 70's vibrochamp , mesa mkIII U.S. Vox pacemaker
Rock , pop rock & Blues style's mainly played
Gtr's Musicanman " Luke " wolfgang [ carved top w pearly gates ] Hondo lazer , Warmoth strat
Fx t.c. 2290 , Lexicon tc verb
Pedals tbone plexi , t.c. chorus , various handmade & usual suspects t.s. , zen , CB wah ..........

Casey_Butt
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Re: Designing New Effects Pedals

Post by Casey_Butt » Thu Dec 05, 2019 11:08 pm

okgb wrote:
Thu Dec 05, 2019 2:11 am
F-You Casey! now I gotta buy all your stuff!
Haha. I've got to build them first... probably be another few months before things get off the ground.
okgb wrote:
Thu Dec 05, 2019 2:11 am
I really would like to have a two preset for the comps like a rythym/lead thing, or heavy & light , but the blend or dry control makes it harder to sound bad with heavy compression
Have you heard the FMR really nice compressor ? not necessarily for gtr but it's an analog circuit with digital control,[ 3 detections methods layered ] you can really compress without sounding overdone
For some reason, I have a soft spot for compressors... not just from a musician's perspective but the spec/electronics side as well. I actually had a RNC a few years ago. I sold it before I moved, but it was a "really nice compressor". Oddly enough, I never did play a guitar through it. Compressors are fascinating beasts - if you design them too "good" they don't play good. It's kind of like tubes - in order for them to do their magic they need to be biased "wrong", driven too hard, etc. Compressors are a balancing act between what's good in engineering spec and what's "good" actually plugged into something. The better you make them on paper, the deader they sound musically. With the compressor my goal was to capture the dynamics of the famous stompboxes but with the dynamics controls of a studio compressor. I always think if David Gilmour, Mike Casswell and Frank Sinatra would have liked it, then I got it.

I hear what you're saying about a two preset compressor. I think to make that useful it would need at least a digital switching scheme... and probably some digital processing as well. In analog, the issue that's limiting me is simply space on the board. That chorus I made literally doesn't have room left on the board for one more single resistor. It's the full size of a 1590BB with just enough space for the battery. I'm finishing the board for the flanger/chorus now and it's going to be tight too. On that one it's imperative that I get the minimum delay down to 0.4 ms, and to do that with modern BBD chips I need two 16 pin ICs in the clock/buffering circuit. It all adds up in real estate. I'm testing the noise gate on that one tomorrow (flangers that sweep much under 5+ ms delay times will start to "thump" at sufficiently high speeds without a gate).

AXiom Flange-Chorus FC-1 - Copy.jpg
AXiom Flange-Chorus FC-1 - Copy.jpg (91.71 KiB) Viewed 28 times
okgb wrote:
Thu Dec 05, 2019 2:11 am
Phaser doesn't have to be true stereo, a dry out on a switched jack works, set up two amps one with tremelo and one without and it feels like it's panning
I wouldn't be able to put it out knowing that it wasn't true stereo. Honestly. When I was making the chorus I experimented with that and the true 180* out of phase stereo lines were so much richer that I lost all respect for Boss. :) The MXR does it, as did the old Boss CE-3. I don't understand why Boss "updated" to the CE-5 and CH-1 and went to wet/dry. What I did with my stereo chorus is make the two lines 180* out of phase, but have separate controls for each channel so you can have wet/dry (on either side), wet/wet (180* out) or pure vibrato in both channels (again 180* out - that's freaky).
okgb wrote:
Thu Dec 05, 2019 2:11 am
How does you're chorus compare to the classic tc SCF ? [ my benchmark ]
I bought or built, simulated and tested 11 different choruses to make that design - all the Bosses, the MXRs, Arion SCH-1, TC SCF, etc. The SCF was one of the most complex (the rack unit Boss CE-300 was probably the most complex... and there's a fairly gnarly one built into the old Boss BE-5 multi-effects unit). They all do pretty much the same thing with the biggest defining factor being the center delay time. The old Boss CE-1 was centered faster than most choruses (like 5ms or less) and that gave it it's unique sound. Some newer choruses can delay 20+ ms. What made the SCF complex wasn't so much the chorus action - which was actually fairly simple and it's LFO was fairly standard - but rather the compander parts (it has both a NE570 and LM13600 OTA for that). I think what gives it its famous sound is the 180* true stereo outputs. It doesn't sound all that different from a slightly modded CE-3 I also had for comparison. In the end, I decided to go with pre-emphasis and de-emphasis circuitry instead of companding because while companding is clearly better for noise reduction I also feel it loses a bit of dynamics on really clean, quiet playing. That and the extra real estate space made me go with filtering. I also added a SWEEP control that adjusts the modulation gradually from square to sinusoidal to triangular. Triangular is fairly standard but at slower speeds sinusoidal sounds very smooth and is a definite edge for choruses that can do it.

So what I did was make the outputs 180* out of phase but with separate controls on each channel so you can adjust the dry-to-chorus-to-vibrato however you like. If you want wet/dry, true stereo or both pure vibrato, you can have it. I also put in a "width" control that actually controls delay time, so if you want tight CE-1 style chorus (almost flanging) you can adjust it for that or you can have very deep, wide chorus of 20+ ms. To account for the tonal differences in choruses (and what type of instrument you're playing) I put in effect treble and bass controls that adjust what frequencies the modulation is applied to. If you want unmodulated bass (so you don't get sea-sick after a few minutes) you can adjust for it. If you're playing with a lot of distortion and don't want that tinny effect on the high frequencies, you can filter it off. On the other hand, if you need the shimmering highs for acoustic or clean playing you can dial it in.

So, essentially, the chorus has enough range to cover just about any chorus sound you can think of. You can set it to sound like a SCF if you want or a CE-1 if you'd like that. It's a matter of adjusting the delay center (WIDTH), the band over which the effect is applied (E.BASS and E.TREBLE), and what the stereo outs are set to. I deliberately didn't want it to be another "flavor" of chorus, but one capable of covering the full spectrum of what the various famous choruses can do.
_ JVM410H: "Blackface" Clean channel, "Plexi" Crunch channel, "Dual Rec" OD2 channel, 3rd stage bias pot with switchable 100nF bypass cap, switchable 470k/470pF "treble peaker", OD1/2 Orange and Red extra gain pot, signal boost into power amp, PI voltage set to 2203 levels, 5H choke w/ 50uF on screens, -ve feedback pot.
_ Marshall 2203/1959 clone - switchable (with FX loop, resonance control and -ve fb pot) built from a Peavey Windsor 'donor' head
_ Fender Deluxe Reverb clone head
_ ADA MP-1, ART Power Plant, Tech 21 PSA-1
_ 1960A cab w/ Celestion G12-65s and G12-75Ts in X-pattern, Peavey JSX cab with Celestion G12M's (UK 6402 cones)
_ Fender Pro 185 (rebuilt) - open back 2x12" with Jensen C12Ks

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