The Truth About True Bypass

Some boutique effects pedal manufacturers these days tout the idea that true bypass is an essential feature to have. However, other quality manufacturers do not include it in their pedals and some go as far as to recommend against it. Let’s take a look at true bypass and the alternatives and try and make some sense out of it all…

What Is Bypass?

Bypass is the method used to turn off an effect when not using it. As you may know, the power is not turned off when you step on the switch, the guitar signal is simply routed away from the effect circuit (bypassing it), and routed directly to the output.

Types of Bypass

There are a few different ways to achieve bypass. Let’s take a look at then now…

True Bypass

True bypass simply switches both the input and the output away from the effect circuit. When bypassed, it is the next best thing to having a single cable plugged directly from your guitar to your amplifier, having little to no effect on the signal at all. The downsides to true bypass are that it is more prone to switch noise and does nothing to alleviate the problems often encountered with more complex effects chains, long cable lengths or substandard cables. Finally, some pedals are not suited to true bypass – particularly the time-based effects such as reverb and delay, where true bypass will cut the delayed signal short.

Output Switching

Output switching leaves the input connected to the circuit at all times, and merely switches the pedal’s output between the circuit’s output and the input. Output switching is common on many vintage effects and is a bit of a compromise as the circuit is always partially connected to the signal line. The effects most often accused of “tone suck” (especially vintage or vintage-style wah pedals) are usually output switched.

Active Bypass

Active bypass runs the signal through a buffer (preamp) first, switches the signal electronically, then buffers the output too. The buffers don’t boost volume, but change the signal from high to low impedance and are always in the signal path, even when the effect is bypassed. The buffers ensure that the guitar and amp (or next effect in a chain) always “see” the same impedance whether the effect is bypassed or not and do away with switch noise completely. Active is also a bonus when you are running lots of pedals, as the low impedance signal is much less prone to picking up noise in cables, plugs and sockets and avoids treble loss when running long cable lengths (and all those short cables on a board add up quickly). A well designed and made active bypass can be tonally transparent, not adding or subtracting anything audible from your tone or dynamics.

From all this it’s easy to think that active bypass is the be-all and end-all of effects bypass. Unfortunately, not all circuitry is designed and made equal and some less expensive pedals compromise on the quality of the buffers, which affect the tone of the pedal both in use and bypassed. Also, by the time you have a pedalboard full of pedals, even with good buffers, the tiny effect each has on the tone can accumulate until it becomes an audible degredation or noise.

Solutions

So, as you can see, each type of bypass has it’s pros and cons. There are however, ways to minimise the bad effects (as it were) of each and maximise the good.

Keep it Simple

A small pedalboard with six or less pedals will work best if they are all true bypass and all cables kept as short as possible. This is the sweetest, simple solution to tonal bliss and the perfect solution for tonehounds.

Complex Boards

If you simply must have a whole array of effects on your pedalboard and/or want to set up complex chains, then a good active bypass pedal at the front of your pedalboard (your compressor or drive would be perfect candidates) is the way to go with as many as possible of the other effects being true bypass. The buffering will retain your tone [i]better[/i] than a complex board full of true bypass pedals will and you’ll keep the adverse effects of having too many buffers in series. If all your pedals are already true bypass, consider adding a good sounding preamp pedal to the front of the chain, set it to unity gain (no volume boost) and leave it on all the time.

For The Troublesome Individual(s)

If you cannot live without a specific but troublesome vintage wah or fuzz pedals with output switching, get a true bypass loop switch pedal and run the problematic pedal “always on” in the loop, using the loop pedal to switch it in or out. If you have a few pedals that fit this description, there are even models that allow you to use up to eight effects, each in their own true bypass loop.

In Conclusion

The most important thing to bear in mind is if it sounds good, it probably is. Don’t worry about “solving” problems you can’t hear. If you want to check for tonal degredation, the best way to do it is plug in to the amp directly then via your pedalboard with all the pedals bypassed (you couls also use a true bypass looper to bypass your entire pedalboard). If you hear a big difference between the two, then only should you start looking for a problem.