What Is True Bypass? A Simplified Explanation February 18 2014, 0 Comments
When you're buying your first guitar pedals, you'll probably notice one term keep coming up over and over again – true bypass. However it's not always clear what it means.
There's a lot written about true bypass online, and it can get very technical and hard to understand. In this guide we'll keep things simple and tell you about the basics of true bypass; hopefully in clear and simple language and without the need for complex schematics!
If you're after true bypass pedals, our Biyang pedals are all true bypass.
True bypass is to do with a guitar pedal when it's part of a chain, but is turned off. So if you're going to get a pedal which will be on all the time, true bypass won't matter to you too much.
However if a pedal will be on and off frequently (like with a fuzz pedal), then true bypass does matter. This is because (if the pedal's not true bypass) it's still connected to the effect circuitry. Even when the pedal isn't in use. This can substantially alter your sound and lead to tone loss because the circuitry of the pedal can “suck” away some of your tone.
What a true bypass pedal does it this – it bypasses the circuitry of the pedal as if there wasn't a pedal there at all. It means the pedal, when turned off, acts more like an extension of your guitar cable. Hopefully these two very simple pictures will help explain this in further detail:
Hopefully you can see how, theoretically, the left pedal should sound better than the right one. Obviously when these pedals are on, the signal path would simply flow through the "Guitar Circuitry".
How Do They Actually Work?
Let's get a (tiny) bit more technical. If you actually open a pedal up, the above pictures would be pretty hard to see. To the untrained eye a true bypass pedal would look the same as a non true bypass one. One major difference is the switches used.
As we said above, a true bypass pedal pedal should bypass the circuitry of the pedal - this includes the LED too. This can be done using a Triple Pole Double Throw (3PDT) switch - both the LED and the signal can be bypassed this way. A 3PDT switch is common in boutique pedals, but because of its added expense (and unreliability) a Double Pole Double Throw (DPDT) switch is used in most mass market true bypass pedals. However if it's connected to the LED, it's not real true bypass. However special circuitry can be used to overcome this .
So the above two switches (used correctly) simply allow the two circuits (pedal on & pedal off) to be electrically separate. A non true bypass pedal on the other hand will usually use a SPDT (single pole double throw) switch. With this switch, when the effect is off, the circuitry is still part of the connection. This provides an opportunity for the tone to become “lost”.
Are There Any Disadvantages?
So we've established that a true bypass pedal should sound better than a non true bypass pedal when it's turned off. But are there any disadvantages associated with true bypass?
Adding Cable Length
You may know that the longer the guitar cable, the more tone loss, especially towards the high end of your sound. Having several true bypass pedals in your setup is similar to adding to the length of your guitar cable. So with enough pedals, you could experience loss, especially when you consider the patch cables connected to your pedals too. However it takes quite a few pedals to create a noticeable difference. With just a few, the difference will be barely noticeable.
With some pedals (such as delay or reverb) there may be a problem when you turn the effect off. You may want the effect to gradually & subtlety fade away. However remember how true bypass works – the effect will be cut out from the guitar signal path as if it never existed. This may be undesirable for some guitarists. In some cases non true bypass pedals can create a little bit of a gradual fade out with some effects.
I Keep Reading About “Buffers” - What Are They?
Again, this is an area where people like to go into excessive technical detail. Basically a buffer can help preserve your guitar sound when you have long cables or a lot of pedals. It helps keep a natural sound as if you were using a short guitar cable. Buffers can either be in the form of a separate pedal, or actually built into an effect. For new players buying their first few pedals, they're not something to worry about.
What's the Bottom Line?
As a beginner you don't want to overcomplicate things. If you're thinking of getting a few pedals then they'll probably sound better if they're true bypass. But at this stage, time spent worrying about your tone will be better spent practising.
Remember that sound, and what sounds “good” is subjective. So in a way, what I've told you here shouldn't matter too much. If it sounds good to you, then it is “good”.
Also remember that there are thousands of different pedals built in different ways. And that's not including boutique pedals. Any one of these pedals could be built differently than what has been generalised here. Without opening them up, and having the knowledge of electronics to actually know what you're looking at, there's no way for sure to know exactly how it's built.
So when buying pedals, rather than asking if it's true bypass or not, just ask yourself “Do I like the way it sounds?”. It's that simple.
Want to Know More?
Hopefully this article has at least brought you up to speed on some of the terminology which is often thrown around and given you a basic understanding of the terms. But hopefully we've helped you realise there's nothing wrong with the “I don't worry too much about tone – I just play” attitude. Especially at this early stage in your guitar playing life.
As we said in the start of the article, we've tried to keep everything nice and simple. But if you to get a little bit more technical check out this page. It gives you all the technical details any budding audiophile you could want.