Musicians are picky about their tone, and none more so than effects enthusiasts. From the particular stomp boxes you choose to their placement, your pedal collection is just that—yours. But no matter what pedals you select, what cables you prefer and how you organize them, one thing is certain: It all affects the overall quality of your tone. All of it.
You may already be an effects expert, or perhaps you’re just starting to dabble. Either way, being educated about different types of pedal circuitry can help create the sound you want . Different types of effects wiring can either aid or hinder your signal, and that’s where the concept of “true bypass” comes in.
How Do Pedals Work?
First, let’s look at the basic switching of a traditional stomp box without true bypass. Stepping on the footswitch activates the pedal and places it in the “on” position. When an instrument is played, the signal passes through the pedal circuitry, and the desired effect is produced before reaching the output. In the “off” position, the signal passes through the pedal without triggering the effect—that is, it bypasses the pedal circuitry that creates the effect.
Easy enough, right? Well, the reality isn’t so cut and dried. Through the late 1970s, pedals were designed so that signals didn’t technically bypass the effect wiring in its entirety. A signal had to partially pass through a pedal’s circuitry, even with the pedal in the off position. The design often caused a loss in high frequencies, which is why many musicians started looking for more organic-sounding alternatives—i.e., a “true bypass.”
How Does True Bypass Work?
The concept of true bypass had, in fact, been around for a couple decades by then--in fact, the mid-’60s Arbiter Fuzz Face distortion pedal popularized by Jimi Hendrix featured an early incarnation of true hardwire bypass.
So, how exactly does this feature operate? A true-bypass pedal has special switching that routes a signal through the effect circuitry or from input to output directly. If you dissected a true-bypass pedal, you’d notice the double-pole/double-throw (DPDT) switch that enables this kind of signal routing. Using the footswitch to alternate between throws, a player can produce the effect or cleanly bypass it through the secondary circuit.
The benefit of true-bypass circuitry is that by sending a signal straight to the amp, the signal completely clears the circuitry that creates the effect (thus the name “true bypass”). The signal remains fully “intact”; passing through the effects pedal with no unwanted tonal coloration, or loss of strength/frequencies.
What are the Setbacks?
Though true-bypass pedals certainly have their advantages, it’s important to note that they’re not for everyone. Their benefits are subjective and dependent on your needs as a player.
They’re best for musicians with a limited number of pedals (ideally three or four). The same cardinal rule applies: The farther a signal has to travel, the greater the possibility for signal loss. Using a lot of pedals essentially duplicates the effect of an extremely long cable. More pedals also increases the likelihood of more prominent switching noise as you alternate stomp boxes.
Many pedals without true bypass contain buffering or preamp circuitry that helps condition the signal and travel through longer pedal chains without losing strength. With a large collection of true-bypass pedals, a buffer at the beginning of the chain can give the signal the added boost it needs to travel through the entire effects setup, keeping its tonal integrity intact.