How do you prevent buffered (modulatn) pedals from clipping?

[mathias]

Iv'e got some buffered pedals (rather than true bypass) on my pedal board near the end of the chain, after my dirt and a vol jr pedal. It seems like I'm getting clipping/distortion in the buffered pedals (not enough headroom on them? dunno if you can add more voltage to Boss or Behringer style pedals...) because I'm hearing it even when I just use a SHO-style boost. Turning down the volume/output on all my dirt to below unity gain seems to work but then I have to boost at the end, which seems like a losing battle of tweaking and trying to match volumes. It's almost like I need a preset volume pedal behind the modulation that I can kick in at the same time as my dirt, but that also seems un-ideal.

What do you do to prevent your buffered pedals from clipping? (Besides just not using non-true-bypass pedals -- I guess this could also be a question of how do I keep my modulation pedals from clipping when they're engaged, since I have the option of putting my Samurai Switch around the buffered pedals to take them out completely.)

[goroth]

No idea as to the actual question but where you been dude!!?

[mathias]

but where you been dude!!?

I think the solution to my problem is gonna be rehousing the behringer pedal in a new box with true bypass.. shouldn't be terribly hard but it's a lot of work for an (admittedly good sounding) $25 pedal :-) And I'll get a momentary stomp switch for its unlatch feature, which will be nice and sturdy.

[mathias]

Oh hey -- the Samurai Switch was the solution after all. The Samurai Switch lives towards the beginning of my chain so it makes sense that inputs aren't clipping yet.

The SS loop gives me a true bypass option, and it turns out the pedal that I really cared about adding to my board (The Behringer VB-2 clone) makes cool spaceship noises when paired in a feedback loop with a little plastic Dano reverb. Zoom zoom!

[rustywire]

This is what lead me to sell a beloved Maxon CS-550.
Gorgeous chorus sound, downright ethereal...but if you set the mix pot +50% wet the headroom would vanish and it would get...ticky.

In fact, just about every single chorus/pitch vibrato pedal I've tried, has clipped for me in an unmusical, signal-too-hot-for-the-microphone kinda way
I use low output single coils...figured this kept happening because I enjoy boosting them with much gain. Much gain
Only when finally scoring a killer uni vibe clone, did I realize it isn't me after all!
Never had these issues with phasers & flangers either. Just op-amp based chorus/vibrato pedals, especially with a blend/mix pot.
Even the outstanding CCv3 was prone, but not the Tremolessence.
When playing clean? Never a problem. But restriction for me to play clean? That's a problem

[goroth]

I know Ryan has talked about a trade off between headroom and noise when it comes to the bucket brigade chips used in the Cosmichorus. Less noise= less headroom. I've noticed this issue with my old Boss BF-2, and to a certain extent the CCv3. Could just be just that BBD chips are old and noisy and you can't get super amounts of headroom out of them, especially not at 9V.


anyways, welcome back from outerspace duder!

[mathias]

In fact, just about every single chorus/pitch vibrato pedal I've tried, has clipped for me in an unmusical, signal-too-hot-for-the-microphone kinda way
I use low output single coils...figured this kept happening because I enjoy boosting them with much gain. Much gain
Only when finally scoring a killer uni vibe clone, did I realize it isn't me after all!

Yup, this was the Behringer VB-2 (vibrato) clone pedal. I got it literally today and immediately identified it as clipping in a not-at-all-nice way as you describe.

I've got a Wilson Haze (univibe-type pedal) coming soon that I'm hoping doesn't have this issue, but I'll be putting it at the beginning of my signal chain because it makes the most sense to put the dinosaur-swamp-chorus circuit there.

anyways, welcome back from outerspace duder!

thanks!

[chaseblissaudio]

Really interesting discussion here. With regards to vibrato/chorus pedals, the nasty clipping you are hearing is almost certainly the bucket-brigade chip clipping. They just don't have a ton of headroom, and sound pretty bad when they clip, especially if the bucket brigade chip isn't biased well. That said, your concern is something I was *very* concerned with when I developed Warped Vinyl - I wanted it to be able to eat up a really hot signal before it and still sound really good. It's strange nobody talks about this issue more. I guess most people just don't boost the hell out of stuff, or something?

You're absolutely right that this can also be a problem with buffered pedals, if you send an extremely hot signal into them. Again, you just don't see this as a "pro / con" in the true bypass vs. buffered debate.

Anyway, cool "problem" and sounds like you were able to find a good solution to it.

[Doctor X]

I use low output single coils...figured this kept happening because I enjoy boosting them with much gain.

how high are the pickups? maybe a lowoutput single generates a hotter signal when its close to the string, than a higher output one further away

i've sold a few pedals in the past that clipped, maybe i was a bit hasty to do so.
what i do now is i go straight into the pedal that clip, and i lower the pickups until they don't clip anymore.
and thats the measure i use to determine the pickup height.
even though i end up boosting the signal with comp/buffery thing, i dont think anything is clipping anymore

[rustywire]

Hm, that's possible, certainly something to consider...and got me thinking. GG Doc.
But if my pickups' height is causing op-amp choruses to clip, then that's tough titty for me.
My Duo Sonic clone doesn't allow for easy pickup adjustments, they're pretty much fixed to the pickguard. I could go in and shim, but It's a sub $100 beater guitar so I'm not worried about it.
My *liability instrument* the '63 Casino has a dog-ear p90 with the pole piece screws, and I have everything where they sound how I like with both clean and/or fuzz, for a base tone to build upon. Never put it on a meter but I can hear it's conspicuously lower output compared to other p90s I've played/heard.

Either way I'm unlikely to ever adjust my pickups around chorus/pitch vibrato; it's putting cart before horse and AFAIC just not an essential effect to me in pedal format. There are some easier, temporary workarounds and compromises. Roll back volume knob, attenuate with an eq or preamp pedal etc.

[mathias]

That said, your concern is something I was *very* concerned with when I developed Warped Vinyl - I wanted it to be able to eat up a really hot signal before it and still sound really good. It's strange nobody talks about this issue more. I guess most people just don't boost the hell out of stuff, or something?

You're absolutely right that this can also be a problem with buffered pedals, if you send an extremely hot signal into them. Again, you just don't see this as a "pro / con" in the true bypass vs. buffered debate.

Anyway, cool "problem" and sounds like you were able to find a good solution to it.

I've been away from guitar gear for awhile so I totally missed the Warped Vinyl -- demo video looks great! I'd like to try one out, eventually.

[mathias]

Quick question to the pedal designers here -- is it possible to design a buffer such that it scales the input signal to an appropriate level? I guess I'm thinking automatically/dynamically scaling it versus just having an input volume knob.

I know that there's line-level converters and such that must do something similar. I'm wondering whether you could put something like that in front of a chorus/vibrato circuit such that it doesn't clip, but maintains the same output level regardless.

[D.o.S.]

... like a compressor or a limiter?


[/might be dumb]

[goroth]

Quick question to the pedal designers here -- is it possible to design a buffer such that it scales the input signal to an appropriate level? I guess I'm thinking automatically/dynamically scaling it versus just having an input volume knob.

I know that there's line-level converters and such that must do something similar. I'm wondering whether you could put something like that in front of a chorus/vibrato circuit such that it doesn't clip, but maintains the same output level regardless.

Yeah, just design a buffer with less than unity gain. For example, a typical jfet buffer has a gain of around 0.97 or something. probably quite a few dudes could help do the maths to make it work. Schlatte for one.

[mathias]

... like a compressor or a limiter?


[/might be dumb]

I've never really used a compressor for my playing but this sounds like a great idea. I'll try my Behringer comp before the Vibrato with the sustain and tone set at noon and see whether that helps to buffer the headroom when I'm using gain pedals. Thanks for the idea!