"buffered" pedals

[riffmeister]

Which of my pedals are "buffered" (and is it only when they are switched on?)

Dunlop Crybaby 535Q wah
Maxon Analog Delay
Fulltone Choralflange
Voodoo Labs Analog Chorus

 

[jrockbridge]

I don't know the specifics about your pedals. In general, pedals without a true bypass switch have a buffer. The buffer is on when the pedal is off.

Some buffers are not very good and can have adverse affects on tone. So, a trend developed in the gear industry to design pedals with TB switches. The theory is that a TB switch will eliminate the tone sucking problems caused by specific types of effects or bad buffers. The reality is that a long chain of TB pedals may experience some signal loss which has an adverse affect on the tone as well. Also, when switching a TB pedal on or off, there is often an audible click or pop sound.

To address the problems of signal loss and drops in high frequency, gear makers offer pedals with the specific function of being a buffer. So, contrary to popular guitar culture, a buffered pedal is not necessarily a bad thing. In fact, having a few good pedals in the chain that just happen to have quality buffers built into them instead of TB switches may be a benefit.

FYI, certain types of pedals, like a classic fuzz face circuit, will not sound right with a buffer in front of them, so pedal order can become critical. Also, a wireless guitar setup will use a buffer, so plan accordingly.

 

[Blix]

Which of my pedals are "buffered" (and is it only when they are switched on?)

Dunlop Crybaby 535Q wah Not true bypass, sucking tone
Maxon Analog Delay True bypass
Fulltone Choralflange Both TB and buffered bypass, not sucking tone
Voodoo Labs Analog Chorus True bypass

Answers in bold above.

 

[riffmeister]

Thanks for the helpful/educational responses.

Blix......so the the wah is "buffered" when on and off?.......and can you explain more about the Choralflange, is there a dip switch inside to switch between TB and BB?

Thanks again!

 

[jrockbridge]

FYI, traditional wah pedals (fassel type) are notorious tone suckers. They load down the pickups reducing dynamics and high frequency. It's the nature of the circuit. That's one pedal that can REALLY benefit from a true bypass switch. Yet, many of them don't have TB. Crazy.

My old Crybaby was a tone sucker until it was modified with a TB switch. Also, it has a multilevel gain switch mod.

I also have an EX7 with a couple of digital models of wah pedals. That pedal has a buffer which is good IMO.

 

[Blues Lyne]

Most any pedal acts as a buffer when on*, so when wondering if a pedal is buffered you are usually talking about whether it is buffered when bypassed.

*So we don't get all confused (or perhaps to confuse matters more), some pedals have an input buffer as the first thing and an output buffer as the last thing in the pedals circuit. This buffers the pedals circuit from what comes before and after it. Some pedals don't have input and/or output buffer, so the pedal itself isn't buffered from what comes before or after it.

The reason I say most pedals act as buffers when on is because even if the pedal doesn't have input and output buffers, the circuitry of the pedal itself creates a buffer so that any thing coming after the pedal is buffered from what comes before the pedal when the pedal is turned on. Any pedal that is turned on will keep a long, high capacitance cable run from the pedal to the amp from loading the pickups of the guitar, but the pedal itself may load the pickups if the input impedance is too low (you generally want a low impedance feeding a high impedance), or the long cable run could load the output of the pedal if the pedal's output impedance is too high. For example, a Fuzz Face will load the guitars pickups when it is on because the input isn't buffered and it has a low input impedance. However, when it is turned on it will act as a buffer between the pickups and anything that comes after the Fuzz Face. Generally this isn't an issue because you can dial the pedal in to sound how you want when it is on. In the case of a Fuzz Face the loading of the pickups is part of what gives it its sound and makes it react to the picking and volume knob changes the way it does. You are generally concerned with multiple bypassed effects and the capacitance of your cable run from loading the pickups when your pedals are bypassed. When buffered inputs and outputs become an issue is when two pedals don't have an optimum impedance match between them and and turning one on while the other is already on can change the sound drastically. Some have found this to be an issue when using an Eternity with certain other pedals because it doesn't have a buffered input or output.

Ok, that sounds a bit confusing, so maybe this will help. Strat > Cable > Pedal > Cable > Amp. Any pedal will buffer "Strat > Cable" from "Cable > Amp", but the pedal itself will not be buffered from "Strat > Cable" or "Cable > Amp" unless it has input and output buffers. If you add a second pedal Strat > Cable > Pedal 1 > Pedal 2 > Cable > Amp, when the first pedal is on it will buffer "Strat > Cable" from "PEdal 2 > Cable > Amp" but pedal 1 will not be buffered from "Strat > Cable" and Pedal 2 unless it has input and output buffers.

*******Disclaimer************* I'm no expert, this is just my understanding of buffers in pedals.

 

[Rumblemeister]

If you want to know if a pedal is buffered, disconnect battery and/or remove power. When the pedal is supposed to be "off" the signal will not pass through.

 

[chervokas]

......so the the wah is "buffered" when on and off?.......

Vintage and vintage style wah circuits are typically neither buffered nor true bypass. They're "hardwire bypass" which means some part of the effects circuitry is loading the guitar even when the pedal is switched off. In the case of the wah typically the load impedance is low enough to cause "tone suck" -- changing the frequency balance and reducing overall level.

Both true bypass and buffered bypass are bypass schemes designed to combat the tone suck experienced with hardwire bypass pedals that have input impedances that are too low.

 

[buddachile]

Most any pedal acts as a buffer when on*, so when wondering if a pedal is buffered you are usually talking about whether it is buffered when bypassed.

*So we don't get all confused (or perhaps to confuse matters more), some pedals have an input buffer as the first thing and an output buffer as the last thing in the pedals circuit. This buffers the pedals circuit from what comes before and after it. Not all pedals have input and/or output buffer, so the pedal itself isn't buffered from what comes before or after it. The reason I say most pedals act as buffers when on is because even if the pedal doesn't have input and output buffers, the circuitry of the pedal itself creates a buffer so that any thing coming after the pedal is buffered from what comes before the pedal when the pedal is turned on. For example, a Fuzz Face will load the guitars pickups when it is on because the input isn't buffered and it has a low input impedance. However, when the Fuzz Face is turned on it will act as a buffer between the pickups and anything that comes after the Fuzz Face.

This is the way to think of it.

BTW, Maxon AD9 is buffered (I'm pretty sure), but the AD9 Pro and the AD-999 are TB.

 

[Kelly]

Thanks for the helpful/educational responses.

Blix......so the the wah is "buffered" when on and off?.......and can you explain more about the Choralflange, is there a dip switch inside to switch between TB and BB?

Thanks again!

Yes, there is a dip switch inside the choralflange to change between buffer and true bypass.

 

[riffmeister]

Yes, there is a dip switch inside the choralflange to change between buffer and true bypass.

Ah yes.......I did a really unusual thing just now......I got out the leaflet that came with the CF and read it. Gotta try it in "buffered" mode now......

 

[Powder Jellyfish]

If you want to know if a pedal is buffered, disconnect battery and/or remove power. When the pedal is supposed to be "off" the signal will not pass through.

I think this is the Bypass test, you're talking about !

 

[Vulteroz]

Crybaby 535Q it has 2PDT switch and no LED- i dont see reason why it should not be a true bypass? I beleve its a true bypass, when i put after mine 535Q a fuzz face, fuzz reacts like i have my guitar directly plug in the fuzz


Maxon Analog Delay. Witch one? there are couple different models in the last 20-30 years, some are TB some are not

 

[Hector Arcadius]

If you want to know if a pedal is buffered, disconnect battery and/or remove power. When the pedal is supposed to be "off" the signal will not pass through.

+1

Exactly.

I think this is the Bypass test, you're talking about !

He is referring to the method with which you can determine if there is buffer in play when your pedal if ''off''. Which is what the OP was asking.

And he can verify with this that the 535Q has no buffer interferring with your signal when disengaged, therefore... no tone sucking issues from the pedal itself.

 

[Musikerochan]

If you want to know if a pedal is buffered, disconnect battery and/or remove power. When the pedal is supposed to be "off" the signal will not pass through.

not a true TBP test method. some vintage pedals pass signal when in bypass and DC input removed, but some parts of the circuit are still hanging at either the input or output of the " bypass" signal

 

[chervokas]

As per Dunlop's list here http://www.jimdunlop.com/blog/what-is-true-bypass/ ...the Crybaby 535Q is neither true bypass nor buffered bypass but is, like most wahs, hardwire bypass.

Hardwire bypass is exactly the sort of "tone sucking" circuit that both true bypass and buffered bypass were designed as solutions for.

With hardwire bypass the impedance of the effects circuitry always loads the device in front of it whether the pedal is switched on or off, and usually this means that the device will load the guitar with too low of an impedance causing signal loss and tone changes. This is very typically the case with hardwire bypass wahs.

With buffered bypass pedals a buffer ahead of the switching always loads the device in front of it, whether the pedal is on or off, but the buffer has sufficiently high input impedance so as not to cause signficant signal loss. With true bypass switching when the pedal is off the signal goes straight from input, through the switch to the output with out being loaded by any part of the effects circuitry, but, obviously, the device in front of the effect is loaded by the impedance of the effect's circuitry when the pedal is switched on. Both, as I say, are solutions for the tone sucking that results from hardwire bypass pedals with relatively low input impedances.

 

[ylo]

Chervokas: I believe some manufacturers use "hardwire bypass" to mean that the input is hard-wired DIRECTLY (well, through a DPDT or 3PDT switch usually) to the output, other pedal circuits switched out in bypass mode, hence no tone suck.

I'm not saying you are using the term incorrectly, just trying to reduce any confusion.

 

[chervokas]

Chervokas: I believe some manufacturers use "hardwire bypass" to mean that the input is hard-wired DIRECTLY (well, through a DPDT or 3PDT switch usually) to the output, other pedal circuits switched out in bypass mode, hence no tone suck.

I'm not saying you are using the term incorrectly, just trying to reduce any confusion.

Yes, Dunlop does in fact use the terminology, but on the page I linked to the company has a chart detailing the bypass schemes on all their pedals, and some are listed as "hardwire" like the wah in question, some "true hardwire" like, say the MXR Carbon Copy (and of course some are buffered, some are relay switched, etc.)

However, I just noticed this language at the very bottom of that chart w/ respect to the wah in question:

*The 535Q is almost true hardwire bypass. While the circuit is arranged for true hardwire bypass, there are very large resistors hanging off the input and output. These act to discharge any leakage from input and output capacitances, thus reducing the amount of ‘pop’ heard during switching.You must remove R41 and R42 in order to make the 535Q true hardwire bypass.