# SVDS / SoloDallas Storm



## Chuck D. Bones (Apr 25, 2020)

This is a clone of the SoloDallas Storm, same as the Closed Circuit Booster Limiter.  I built the Aion Gale because the PedalPCB board was not yet available at the time.  Nice tone, subtle limiter, plenty of clean boost available and the 386 can drive a mile of cable.  Read the Aion build docs about the origins of the SoloDallas Storm, pretty interesting!  The Aion board contains two optional capacitors, both of which I ended up installing.  One is a 120pF cap at the input to filter out RF interference.  Most pedals have that, so including it was a no-brainer.  The 2nd cap is a 10uF in parallel with the opto's LED.  I started out with this cap omitted.  Notes at the bottom end of the scale had some distortion at higher limiter settings. Bench testing confirmed that the opto's response time was fast enough for the LED ripple to modulate the LDR's resistance at low frequencies.  Some optos are slow enough that this is not a problem.  I installed the 10uF cap and the distortion was gone.  The limiter's attack is still plenty fast.  I socketed the 4558D with the idea that I might try swapping opamps.  I was plenty satisfied with the sound, so I left well enough alone.


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## cooder (Apr 26, 2020)

Nice one! I have the pedalpcb one in the works, only the opto coupler missing.
Yes the Aion build docs are really well done with a lot of research and effort.


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## Gordo (Apr 26, 2020)

Nice!  I built the Aion's board as well and it's a regular on my pedalboard. I never did install the caps, but will try them.


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## Barry (Apr 26, 2020)

Nice looking build


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## HamishR (Apr 26, 2020)

If it ever starts to sound a bit crooked it's because your boards are installed crooked. Does it ever sound crooked?


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## Mourguitars (Apr 26, 2020)

Awesome Chuck !

How does it sound ?

Mike


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## Chuck D. Bones (Apr 26, 2020)

HamishR said:


> If it ever starts to sound a bit crooked it's because your boards are installed crooked. Does it ever sound crooked?



I was waiting for someone to bust my balls on that.  I didn't notice that the board was cockeyed when I was soldering the pots.  I wasn't going to reflow the pots just to straighten out the boards.  I like asymmetrical clipping, so an asymmetrical board doesn't bother my sensibilities.


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## Chuck D. Bones (Apr 26, 2020)

Gordo said:


> Nice!  I built the Aion's board as well and it's a regular on my pedalboard. I never did install the caps, but will try them.



You won't hear the 120pF cap.  I'd only install the 10uF cap if you notice unwanted distortion when hitting the low notes.


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## Chuck D. Bones (Apr 26, 2020)

Mourguitars said:


> Awesome Chuck !
> 
> How does it sound ?
> 
> Mike



It's pretty transparent, just a little bit of the top end sparkle is shaved off.  With the LIMITER dialed down, the dynamics are pretty much intact.  Turning up the GAIN and the LIMITER up reduces the attack, just like you'd expect.  It's quite smooth, no "breathing."  Plenty of gain and volume available if you want to overdrive an amp.  Makes me want to play an AC/DC song.

Now here's the stupid part:  When I first reassembled it after painting, it hummed like crazy even in bypass.  I didn't follow my own rule of cleaning the paint off of the inside of the box.  It looked pretty clean, but it turns out there was a thin coating of over-spray around the jacks on the inside, just enough to screw up the grounding.  Some cursing and a few minutes with some emery cloth and now it's working like it should.  For that, I'm awarding myself _*Asshat of the Week*_.


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## music6000 (Apr 28, 2020)

Yes, That looks better!


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## Chuck D. Bones (Apr 28, 2020)

Hey, while you're at it, can you clean some of the paint out from the inside?  

Thaaaaaaaaaaaaanks.  That'd be great.


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## K Pedals (Apr 28, 2020)

Chuck D. Bones said:


> This is a clone of the SoloDallas Storm, same as the Closed Circuit Booster Limiter.  I built the Aion Gale because the PedalPCB board was not yet available at the time.  Nice tone, subtle limiter, plenty of clean boost available and the 386 can drive a mile of cable.  Read the Aion build docs about the origins of the SoloDallas Storm, pretty interesting!  The Aion board contains two optional capacitors, both of which I ended up installing.  One is a 120pF cap at the input to filter out RF interference.  Most pedals have that, so including it was a no-brainer.  The 2nd cap is a 10uF in parallel with the opto's LED.  I started out with this cap omitted.  Notes at the bottom end of the scale had some distortion at higher limiter settings. Bench testing confirmed that the opto's response time was fast enough for the LED ripple to modulate the LDR's resistance at low frequencies.  Some optos are slow enough that this is not a problem.  I installed the 10uF cap and the distortion was gone.  The limiter's attack is still plenty fast.  I socketed the 4558D with the idea that I might try swapping opamps.  I was plenty satisfied with the sound, so I left well enough alone.
> 
> View attachment 4140
> 
> View attachment 4141


Sweet!!!
I like that enclosure ...


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## HamishR (Apr 28, 2020)

Sorry mate.  How are the balls?


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## joelorigo (Apr 28, 2020)

Cool! I also have this PCB and the parts are starting to arrive. I didn't include the 2 optional caps however, hmmmm...


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## Chuck D. Bones (Apr 29, 2020)

HamishR said:


> Sorry mate.  How are the balls?


That reminds me of a golfing joke.


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## HamishR (Apr 29, 2020)

You know I was only kidding. Who wants to be a straight? That has artistic flair with a slightly rebellious slant. I think you are saying to the viewer "don't push me Mutha". They can see that you are a fellow not to be messed with because YOU DON'T CARE!! You don't play by their rules, oh no. Sometimes you even use the wrong colour wire - deliberately, not just because you ran out of white.

Or maybe I'm reading to much into it and it's just sloppiness.


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## geekmacdaddy (Apr 29, 2020)

nice, as it usually is


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## Gordo (Apr 29, 2020)

Best ball I hit all day was stepping on a rake in the sandtrap...


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## Chuck D. Bones (Apr 29, 2020)




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## HamishR (Apr 29, 2020)

I feel bad now.  Sorry Chuck. Your pedal is beautiful and individual.


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## Chuck D. Bones (Apr 29, 2020)

These two women are out on the golf course. One of them tees up the ball and promptly shanks it into a foursome.  One of the guys is hit.  He groans and doubles over in pain, clutching both hands below the waist.  The two women run over, all apologetic.  The one who hit the ball approaches the injured man and tells him "I've very sorry I hurt you. I'm a physical therapist, and if you would allow me, I think I could relieve your pain."
The man reluctantly agrees, so the woman carefully loosens his belt and slides her hand inside his shorts.  She gently massages him for several minutes and then asks "Now doesn't that feel better?"
The man replies "That was great, but my thumb is still killing me."


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## beachbum (Feb 10, 2021)

Chuck D. Bones said:


> This is a clone of the SoloDallas Storm, same as the Closed Circuit Booster Limiter.  I built the Aion Gale because the PedalPCB board was not yet available at the time.  Nice tone, subtle limiter, plenty of clean boost available and the 386 can drive a mile of cable.  Read the Aion build docs about the origins of the SoloDallas Storm, pretty interesting!  The Aion board contains two optional capacitors, both of which I ended up installing.  One is a 120pF cap at the input to filter out RF interference.  Most pedals have that, so including it was a no-brainer.  The 2nd cap is a 10uF in parallel with the opto's LED.  I started out with this cap omitted.  Notes at the bottom end of the scale had some distortion at higher limiter settings. Bench testing confirmed that the opto's response time was fast enough for the LED ripple to modulate the LDR's resistance at low frequencies.  Some optos are slow enough that this is not a problem.  I installed the 10uF cap and the distortion was gone.  The limiter's attack is still plenty fast.  I socketed the 4558D with the idea that I might try swapping opamps.  I was plenty satisfied with the sound, so I left well enough alone.


I built one of these recently and curious if yours exhibits similar behaviour. Hi pregain and playing with the threshold yields your standard compressor squish. What I found interesting is actually how the output volume behaves when pushed, especially with the pregain and threshold turned down below 10-11 o'clock. Instead of just getting a clean boost, I'm actually getting a fairly healthy amount of saturation and clipping and it sounds pretty nice going through a super clean signal chain to add a bit of "chucka" to your attacks.


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## Chuck D. Bones (Feb 10, 2021)

I just put mine on the bench.  With PREGAIN & VOLUME dimed and THRESHOLD at zero, the maximum undistorted output is 7.25Vp-p with 280mVp-p input.  The measured gain is 28dB, which is what I'd expect with no compression (THRESHOLD at zero).

Next I tried your settings: PREGAIN & THRESHOLD at about 11.  I could drive the input up to 1Vp-p (that's as high as my sig gen setup goes) with no distortion and 2.5Vp-p output.

I'm not observing the saturation you're describing, however that much output will overdrive most amps or pedals, so maybe the distortion is coming from outside the Gale?

Do you have C5 installed?

What do you mean by "pushed?"


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## beachbum (Feb 11, 2021)

I'll try to record a clip, but I tested it straight into my interface, maybe going through the bigsky cabfilter.

pushed, just meant when you raise the volume past unity gain. 

c5 and c1 were are not installed.


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## Chuck D. Bones (Jun 8, 2022)

Follow-up:
I ended up removing C5, the optional smoothing cap in parallel with the opto's LED.


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## music6000 (Aug 18, 2022)

Chuck D. Bones said:


> Follow-up:
> I ended up removing C5, the optional smoothing cap in parallel with the opto's LED.


Why Chuck, Why?


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## Chuck D. Bones (Aug 18, 2022)

I wanted to restore the slight low-freq grind that the SVDS exhibits.  I can dial it in and out with the PREGAIN & THRESHOLD controls.


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## jeffwhitfield (Aug 18, 2022)

Nice build, Chuck!  

I built one of these some time ago. It's a good pedal...but really only good for a specific use. It's more of a tone sweetener to me. It's got some boost capabilities and the limiter is...err...somewhat limiting (kind of subtle). Really great circuit and perfect for the player looking to get the sound that this pedal helps with. However, I got a Source Audio ZIO shortly after and it ended up kicking this one off the board. I get more mileage out of my Source Audio ZIO and Atlas combo.


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## music6000 (Aug 18, 2022)

Chuck D. Bones said:


> I wanted to restore the slight low-freq grind that the SVDS exhibits.  I can dial it in and out with the PREGAIN & THRESHOLD controls.


Would increasing the limiter pot to A250K make it Squish more????


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## MichaelW (Aug 18, 2022)

I have this on my bench for this weekend. Confused now about the "optionals". Put em in? Leave them out?


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## Chuck D. Bones (Aug 18, 2022)

The 120pF cap at the input will sound the same in or out.  I recommend it to guard against radio interference.  If you don't have 120pF, 100pF will do.

I'd suggest leaving the smoothing cap out, play it and see if you hear any slight distortion when playing open chords.  Depending on the speed of your opto / LDR, that cap may be totally unnecessary.  Or you may like the tone.


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## Chuck D. Bones (Aug 19, 2022)

music6000 said:


> Would increasing the limiter pot to A250K make it Squish more????


No, and in fact it may do just the opposite.  Once IC1.2 saturates, you're not going get any more gain reduction.  If you want more compression, you can increase R3 or better yet, build a different compressor.  This circuit was tuned to have a specific tone and (I can't believe I'm saying this) modding it is probably *not* the best option.  The Hollis Flatline (Madbean Four-One) compressor uses a similar architecture and has more sustain.

I like this one because the limiter is subtle.  I have other compressor pedals for when I want huge sustain.


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