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Is True Bypass better than Buffered Bypass?

Which one is better? I have heard mixed opinions about this topic, and am not sure which side is correct? I have one true bypass pedal and it sounds just as good as all of the rest. So why would it be better/worse?

Is it possible to be neither?

I was also wondering can a pedal be neither Buffered nor True Bypass? Is there something else out there? And how does it compare? All help is appreciated!

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TL;DR

Which is better? That's up to your ears. Both bypasses have trade-offs: True Bypass is the most pure and high-fidelity, but it exposes your signal to long-cable degradation (plus it's more expensive). Pedals with buffered bypass will color your tone (especially if you have many of them), but you can run long cables without worry.

More explanation

True Bypass means that when the pedal is not engaged, your guitar's signal travels directly to the pedal's output along a simple wire. This ensures that the pedal doesn't color the signal, preserving your guitar's tone with the highest possible fidelity. In other words, when the pedal is off, it's as if it's not even there. True Bypass is generally a feature on high-end, boutique pedals, in part because the necessary internal components are more expensive.

Pedal manufactures market True Bypass as the cleanest, most faithful bypass possible. And it is, except for one thing: guitar signals are high impedance. As a consequence, if you run a guitar's signal through a long enough cable, it will start to lose some of the high end. This is why it's hard to find guitar cables longer than about 30 feet, while its easy to find mic cables that are 100 feet or more; mic signals are low impedance and aren't susceptible to signal degradation over long cable lengths.

So if you plug your guitar into a 30-foot cable, plug the cable into a True Bypass pedal, and then plug the pedal into another 30-foot cable before it gets to the amp, the "bypass is a simple wire" nature of True Bypass means that when the pedal is off, you've effectively plugged your guitar into a 60-foot cable, and this will have a noticeable effect on your sound. The more True Bypass pedals in your chain, the longer the effective cable length when they're off, and so the more impedance loss your signal will suffer.

Buffered bypass is designed with exactly this scenario in mind. Instead of the bypass being a simple wire, the pedal runs the signal through a small buffering amp first. This solves the impedance issues and ensures that your guitar's signal won't degrade over the long cable length. But while buffering amps are very very clean, they can't possibly be as clean and true as a simple wire, and so your signal is affected, at least somewhat. The more buffered-bypass pedals in your chain, the more buffering amps your signal goes through, and so the more it's affected.

  • The big problem with buffering amps isn't that they're not clean, but that they shelter a guitar from any downstream impedance effects that could influence the signal that the guitar is putting out. If the impedance effects are seen as a bad thing, sheltering the guitar from them is good. If a guitarist likes what the impedance effects do to his sound, however, such sheltering would lose their benefit. – supercat Sep 29 '14 at 3:01
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This has become a particularly heated area of debate recently on the internet, but personally I think a lot of it is blown way out of proportion. Basically, a lot of older effects pedals (and most current Boss ones) were always "buffered" or non-true bypass. What this means is that even when the effect pedal is off, your guitar's signal is still going through some of the pedal's circuitry, which could potentially degrade your sound/tone. The tone purists will say it "sucks" all the tone out of your signal, so especially when you are using many pedals in your setup, by the end of the chain the sound of your guitar is significantly affected, even when all the pedals are off. This is a very subjective experience and I have never noticed too much of a change, but I only ever use a handful of pedals at a time.

True bypass has become very popular recently because everyone is scared of the "tone suck" so manufacturers are jumping on the chance to make their pedals seem superior. A true bypass pedal will not necessarily sound better by itself than a buffered pedal. There are a ton of great buffered pedals out there, and a lot of them don't have much negative effect on your tone. On the other hand, not all true bypass pedals sound great, so you really need to let your ears be your guide and don't listen to all the hype.

One thing worth mentioning, if you do have a chain full of true bypass pedals, it is often recommended that you include at least one buffered pedal in the chain (usually towards the beginning) to keep the signal from losing some of the high-frequency content that can happen over long cable runs or with many true-bypass pedals chained together. The buffer does this by using a high input impedance to get the most out of your guitar signal and a low output impedance to better transmit your guitar's signal across its entire frequency range.

One interesting product out there that solves some of these problems is the true-bypass pedal switcher. It is basically a box with a number of effects loops, and a true bypass switch to turn on/off each loop separately. This is useful because when you aren't using any of your pedals, your signal goes directly from your guitar to your amp, and doesn't touch a single pedal. The signal only goes to the pedals when you activate their particular loop.

  • Good answer. Your point about putting a buffered pedal early in the chain should perhaps be phrased a bit differently: "driving all the pedals" is not really an issue, you always drive only the first one that's not in true-bypass mode. Unlike a guitar cable, a pedal in true-BP shouldn't even change the capacitive load (though some no doubt do, despite the name). Perhaps the most relevant concern is not to drive the cable going from the pedal-board to the amp, so what I should say is put a buffered pedal ᴀɴʏᴡʜᴇʀᴇ in your chain. – leftaroundabout Sep 28 '14 at 8:15
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    Also, note that a couple of pedals take a good deal of their characteristic sound from the unusual interaction with the guitar: they have a low-impedance input, which largely kills the pickup resonance and takes away a good deal of treble. This won't happen if the pedal comes after a buffered one. (You might argue colouration-by-impedance is horrible design, but then guitar circuits in themselves are horrible design... if I were to decide, I'd mandate guitar manufacturers to make all instruments active.) – leftaroundabout Sep 28 '14 at 8:18
  • thanks for the input, I edited that section for clarity. I'll keep the suggestion to put the buffer early in the chain because that's what most of my research/experience suggests, but worded it differently to imply that isn't absolutely necessary. – Charles Sep 28 '14 at 8:40
  • @leftaroundabout: Tone coloration by impedance interactions is not as nicely controllable and predictable as sound shaping by other means. The question of whether sound is more or less pleasing is subjective rather than objective, but the fact that low-impedance inputs do affect sound in ways which are different from high-impedance devices is not. – supercat Sep 29 '14 at 2:58
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Different amplifier or pedal input stages may have different characteristics. The sound of a guitar will be affected in some measure by the characteristics of the device to which it is connected. To use a mechanical analogy, consider the relationship between the strings and the sounding board on an acoustic guitar. The strings try to move the sounding board, but the sounding board in turn pushes back on the strings. The way in which the strings and sounding board actually move depends in a complex way on the interaction between them.

Many kinds of amplifier input stages are deliberately designed to behave as much as possible like "passive observers" [called a "high-impedance input"], and many amplifier output stages are designed to behave as much as possible like rigid motion controls [a "low-impedance output"]. If the string vibrates by 0.1", then a passive amplifier which was set for a 2:1 gain would not affect the vibration of the string, but would cause anything to which its output was attached to vibrate by 0.2", regardless of how much or how little force was required to do that.

Adding a buffer stage between two devices will make it impossible for the latter device to affect the signal coming from the former. In many cases, amplifiers are deliberately designed to minimize the effect that downstream devices have on upstream ones, so the fact that any residual effect (which isn't supposed to exist) doesn't get transmitted is not a problem. Because the direct signal from a guitar is not driven very strongly, it will often thus be liable to pick up noise. The signal from a buffered bypass may convey the same amount of "motion", but will be driven as strongly as necessary to produce that motion, making it less liable to pick up noise.

Although many amplifiers and pedals are designed to have only minimal effect on the incoming signal, that isn't true of all of them. Imagine, for example, a pedal which was wired just like the tone control on a guitar [e.g. to add a "tone control" function to a guitar which would otherwise lack one]. The tone control circuit sits across the guitar coil's output, and is designed to be electrically "move" easily at low frequencies, but with greater difficulty at higher frequencies. If a guitar were plugged directly into a pedal containing a similar circuit, or if it were plugged in through a pedal with a "true bypass", the tone control would work the same way as on a guitar. If, however, it were plugged in through a pedal with a "buffered bypass", the tone control would have very little effect since a typical buffered bypass is designed to overpower any "stiffness" the downstream device might have.

If an amplifier's input stage would affect the signal that gets fed into it, then such behavior will be totally changed by the addition of a buffered bypass. If such effects were desirable, the lack of them would be a bad thing. If such effects occurred but were considered undesirable, the lack of them could be a good thing. Only if the input stages of the buffered bypass matches that of the downstream recipient of the signal will there be no effect; effects when they occur, however, may be either good or bad. Unless one is deliberately using an amplifier or effects pedal which is designed to affect its input, however, the only way to know whether a change will be good or bad is to try it.

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