Buffer circuit before or after effects

Started by oldrocker, August 13, 2006, 12:58:25 PM

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oldrocker

I was thinking of adding a buffer circuit in my effects signal chain.  Should it be in front of my effects or after?  Where have most who implemented this used it.  I'm speaking of a separate buffer not one that already built into a pedal effect.  And which one would you recommend?  Opamp, Jfet or NPN transistor type?
Another question.  Is the buffer circuit always engaged even when the effect is on or only used when in bypass?

Gilles C

I like a Fet Preamp cable for a start. The preamp is closer of the guitar

http://www.till.com/articles/PreampCable/index.html

A Mosfet Boost is my second choice for a preamp in a box

http://www.muzique.com/schem/mosfet.htm

I've got more choices, but nothing permanent enough to be mentioned...

Gilles

oldrocker

Another dumb question.  I noticed Gilles C. show me links to boosters.  So then Is the StratoBlaster I recently built considered a buffer and if not maybe I could modify it to be one.

Seljer

if you're not using to to boost the signal then its prettymuch acting as a buffer

Gilles C

Yes, the Strato was originally designed to be used inside the guitar. I forgot that one. I still have one in a guitar.

http://alembic.stores.yahoo.net/blaster.html

Gilles

Bernardduur

I use a AMZ Superbuffer at the start and the end of all my rigs and am very satisfied. When you use 1, place it at the start of the chain
Am learning something new every day here

SquareLight | MySpace account

QSQCaito

Im going to build multi fx box, the first 2 circuits have internal buffers, vibin champ and blues breaker, if there are going to be almsot on, is there any need for buffer, what about when bypassed, buffers needed also??

thanks a lot

sorry for thread hijack:P

bye bye

dac
D.A.C

Pushtone

Quote from: oldrocker on August 13, 2006, 02:03:17 PM
So then Is the StratoBlaster I recently built considered a buffer and if not maybe I could modify it to be one.

Yes. 

I built many boosters this summer. The Stratoblaster, among others, has that annoying thing going on
with the vol pot that all the boost is crammed into the last quarter of the rotation.

I replaced the Startoblaster's pot with a 100K resistor and turned it into a unity gain buffer.
The MOSfet booster was mentioned and it has the same problem with the pot that the Stratoblaster had.

I'm about to post some pictures on the picture thread of a Fetzer Valve boost pedal that uses the Stratoblaster as a buffer instead of bypass. So the footswitch selects between buffered bypass and boost. This is great if you have many True Bypass pedals because the moment you turn off the booster on a TB boost you are plunged into tone suck by all the capacitance of 8 (or more ) TB pedals.

A buffered bypass booster is a great pedal to have at the start of a long signal chain of true bypass pedals to prevent capacitance tone suck.

It's also suitable before a long cable run. For fun I connected three 20 foot cables between the buffer and the amp. The "Strat-o-Buffer" drove the load well and it sounded better than a 20 foot cable with no buffer (more sparkly high end).

A few things to keep in mind...

All BOSS pedals use a buffered bypass
Too many buffers = noise
Not enough buffers = tone suck (usually one buffer is enough to drive lots of true bypassed pedals)
The effect of a buffer ends at the start of the next circuit.


A good place for buffers.
1. At the effect returns in a efx loop box.
2. at the start of a long chain of True Bypass pedals. (Buffered Bypass)
3. Before a long cable run.
4. On the output of certain effects that cause a dip in the perceived level, ie Small Stone Chorus, MXR Envelope Filter


Which one would I reccommend?
1. The GGG IC buffer is very small and can therefore go into anything. It's sound is dependant on the type of op amp, but all sound mostly good. Maybe one op amp is noisier than another. Use a socket and have some fun switching a few around. The sound is clean and full range.

2. The GGG Strat-o-Blaster has that pot rotationissue but it makes a great buffer! Bigger than the IC buffer but still quite small. Its sound has some character over the IC buffer with a more pronounced low end along with the strong top end buffers are known for.  I like it because it's not sterile. Remember this was originally designed as an on-board preamp for guitar.

3. MOSfet booster has the least amount of character IMHO. Thinner sounding and it can be noisy (hiss) unless you find a good transistor for it. I have a bunch of BS170 and they are all hissy in the circuit. It's been recommended to me to try a 2N7000 in the MOSfet booster. And like the statoblaster it has the pot rotation issue (and I think it rotated backwards too). It's PCB is also starting to get a bit large for a buffer.

I don't use it much, but I built three GGG IC buffers into a 1590A box if I ever wanted to split the guitar signal 3 ways without loading down the pickups.
It's time to buy a gun. That's what I've been thinking.
Maybe I can afford one, if I do a little less drinking. - Fred Eaglesmith

oldrocker

OK!! :icon_biggrin: Thanks people for all the great responses.  I had a feeling how to use a buffer circuit and I see I was right mostly.  One more question.  Does the Strato need a pull down load resister to eliminate popping or will that 2.2M in the front do that?

hilbi

I use a AMZ Superbuffer at the start and the end of all my rigs and am very satisfied. When you use 1, place it at the start of the chain
Quote

I use also the amz super buffer as first in my signal path.
hilbi

Built so far: PNP FuzzFace, MXR Dynacomp, EA Tremolo, AMZ Mosfet Boost, AMZ Super Buffer, Blue Magic, Peppermill, RM Axis Face, Sparkle Boost, BSIABII, ROG Ruby, AMZ Mini Booster, MXR Phase 45 Univibe, Tremulus Lune, Dallas Rangemaster, Ross Comp

Gilles C

Quote from: oldrocker on August 13, 2006, 03:04:46 PM
OK!! :icon_biggrin: Thanks people for all the great responses.  I had a feeling how to use a buffer circuit and I see I was right mostly.  One more question.  Does the Strato need a pull down load resister to eliminate popping or will that 2.2M in the front do that?

Normally, you wouldn't switch it In an Out of the circuit. You would keep it connected all the time. But if you switch it, use this configuration

http://www.generalguitargadgets.com/diagrams/asb_sc_i.gif