Envelope filters - is a buffer needed?

[blueswah]

Envelope filters in general seem to be touchy about the level of input.
Too little (aka volume on the guitar turned down) and they don't sound right.
Would a buffer between the guitar and the pedal help?

 

[Modulator]

A little compression might help keep the signal at a good level for the env follower. But it could change the envelope a little due to compression.

Maybe just turn up the volume to where you need it? I don't think a buffer would do much unless you got a long ass cable and lots of pedals between the guitar and the env follower, and even then, I don't think it would do much.

 

[kimock]

That's a good question.
I'm going to say it depends on the guitar, the quality of the buffer, and your preference.
I have a really weak Strat (lipsticks) that I think sounds better with my Mutron when I use my Steel Guitar Black Box before it.
Just a little rounder maybe, more 3-D.
I'm betting that's a pickup impedance issue that the BB is helping with, so the success of the buffer into envelope is at least somewhat guitar dependent.
I wouldn't limit the dynamic range with compression tho.
That's all the envelope follower is really following, dynamics. .

Anyway, you don't need a buffer for the effect, but you might like one for the guitar.

 

[blueswah]

Thanks all.

Is there a way to get the input signal into the Envelope filter to be consistent regardless of the guitars volume knob setting?
I guess this is what I was 'thinking' a buffer might help to achieve.
But it looks like that line of thought was/ is a little off base.

Right now I set it up to 'sound right' with the guitars volume maxed.
I use the same guitar/ same pups 99% of the time.

Hmmm, maybe a volume pedal after the Envelope filter would work?
The EF is first in my signal chain, then fuzz, clean boost (timmy), delay.

 

[vulcaniza P]

your problem can be fixed with a compressor not a buffer.


i would always have issues with bass synth pedals acting touchy. then i tried a compressor before the synth.....suddenly the pedal behaved as i wanted.

 

[redeyedjim]

Thanks all.

Is there a way to get the input signal into the Envelope filter to be consistent regardless of the guitars volume knob setting?
I guess this is what I was 'thinking' a buffer might help to achieve.
But it looks like that line of thought was/ is a little off base.

Disclaimer: I have nothing special to offer after kimock's answer, which I agree with...but I do have more info on the above question.

Yes, it is possible to craft a signal chain that is very EF friendly, and behaves just as you described: it takes the signal from the pickups, runs it into a buffer, then runs that out of the guitar to the pedals at full strength so they see a consistently solid signal, then back to the guitar, out through the guitar's volume pot (so you have a working volume control for amp's input volume, post-effects) and onto the amp. That's the essence of the Jerry Garcia unity gain buffer/on board effects loop architecture (UGB/OBEL). I'd guess that's more work/commitment than you want (guitar schematic here, buffer info here), but as someone whose gone down that path, I can tell you that the results are very, very good.

 

[zoooombiex]

Thanks all.

Is there a way to get the input signal into the Envelope filter to be consistent regardless of the guitars volume knob setting?
I guess this is what I was 'thinking' a buffer might help to achieve.
But it looks like that line of thought was/ is a little off base.

Right now I set it up to 'sound right' with the guitars volume maxed.
I use the same guitar/ same pups 99% of the time.

Hmmm, maybe a volume pedal after the Envelope filter would work?
The EF is first in my signal chain, then fuzz, clean boost (timmy), delay.

Disclaimer: I have nothing special to offer after kimock's answer, which I agree with...but I do have more info on the above question.

Yes, it is possible to craft a signal chain that is very EF friendly, and behaves just as you described: it takes the signal from the pickups, runs it into a buffer, then runs that out of the guitar to the pedals at full strength so they see a consistently solid signal, then back to the guitar, out through the guitar's volume pot (so you have a working volume control for amp's input volume, post-effects) and onto the amp. That's the essence of the Jerry Garcia unity gain buffer/on board effects loop architecture (UGB/OBEL). I'd guess that's more work/commitment than you want (guitar schematic here, buffer info here), but as someone whose gone down that path, I can tell you that the results are very, very good.

What he said.

And just to hopefully clarify what seems to be underlying your question -- EF's mainly respond to playing dynamics (both in terms of the overall signal level and the sharpness of the attack on each note). A buffer (at least in the strict sense) shouldn't be changing any of that - it just changes the impedance of your signal so that it is not as affected by long cable runs. (Though it's possible that change in impedance could have some secondary affect on how the EF reacts, as Kimock said.)

The purpose of the buffer in the Jerry setup is just to enable a long cable run directly from the guitar pickup to the pedals, then back to the guitar volume controls. So the EF is always seeing the pickups at full strength (pre-volume control), which helps stabilize the guitar-EF interaction. The buffer is sort of ancillary to that.

Putting a volume pedal at the end of your chain would (kind of) accomplish the same thing as the Jerry setup - guitar at max volume, through effects, then volume pedal at end to control the overall level.

 

[zoooombiex]

your problem can be fixed with a compressor not a buffer.


i would always have issues with bass synth pedals acting touchy. then i tried a compressor before the synth.....suddenly the pedal behaved as i wanted.

FWIW, I've never had much luck with compressors before EF's. That's not to say it might not help in a given setup with your guitar, pedal, amp, etc.

I've just found that (in my setup and in friends') it's usually a matter of (1) getting the right settings (particularly the gain, but also peak) on the pedal for your given style of playing, and (2) actually controlling your dynamics when you go to play (i.e., don't set the pedal while lightly picking at home and then expect it to sound good when slamming the strings at a show).

 

[midwayfair]

A little compression might help keep the signal at a good level for the env follower. But it could change the envelope a little due to compression.

Really, it depends on the kind of compressor and how much boost you're getting out of it for how the compressor works. If you're using a super squishy compressor, you don't want it in front of the filter. It'll trigger all the time or not at all, and I've also found that rippling effects can be introduced by the filter when the signal "rides" the edge of triggering. Sounds gross. A mild boost or less extreme comp, however, can be a huge improvement.

I did a demo that includes a pretty simply envelope filter design where I also showed how it reacts with some boost and compression (Orange Squeezer above unity volume), it might help give a feel for the difference (this should start at 8:28, if it doesn't fast forward [edit: okay, it doesn't start at the right time, just fast forward to 8:28]):


However, there's something else going on here. Most envelope filters default to the "heel down" position. This is why they don't really sound right if you don't feed them enough volume to trigger the envelope. Most envelope filters are also very particular about where the sensitivity (how much volume it takes to trigger) and range (tonal sweep) are set with any given guitar.

A buffer with some gain WILL actually help a little bit. It will boost the highs some and perhaps make the "heel down"/non-triggered EF sound a little more okay. It'll boost the gain so you don't have to play as hard to trigger the envelope.