Ah the old true-bypass or not dilemma. I have been asked several times whether or not true bypass is ‘any good’ or if it truly makes any difference. Now I am not the most qualified person in the world to answer this question, but I will do my best in this article to explain some of the basics.
There are some pro builders out there who stand behind true bypass switching one hundred per cent, and then there are a few who stand against it one hundred per cent and crown a buffered bypass switching to be king. So, who is right? Well, they both are, to me anyway. I am one of those guys who is sat firmly in the middle, on the fence on this one, but I do think that if you are going to use a buffer it should be a high quality buffer that will actually help improve your signal and not just a couple of cheap parts thrown together.
So what is the difference?
True Bypass – This is a switching method whereby when the effect is turned off the signal is sent directly from the input jack, through the switch, and into the output jack, completely bypassing any circuitry.
Buffered Bypass – A buffer is a device which ‘gets back your signal’ after a long cable run. Think about it, you have a really long guitar cable, going into about ten or so effects pedals, then another long cable going into your amp. That is a lot of distance for the signal from your guitar to travel and ultimately high end frequencies begin to get lost somewhere down the line. A buffer can help restore these frequencies by means of amplification and get back your precious top end. A lot of pedals incorporate a buffer to help send a more realistic image of your signal through the effect circuitry. Probably the most obvious example is the Tubescreamer TS808 model. To me I cannot hear much signal loss or degradation when the 808 (or TS9) is in ‘bypass’ mode, but a lot of folks believe they can and prefer to have it modded for a true bypass option.
So, which is right? Well as I said earlier neither option is ‘wrong’, I think it totally depends on the situation. If you are a guy who plugs his guitar into one or two pedals and then straight to the amp, you can probably get by using true bypass pedals, but I believe I can hear a definite difference when using five or more pedals. Try plugging in (if you have them) five or more true bypass pedals (the more you use the more obvious the tonal difference will be). Leave them all in bypass mode and play your through your clean channel, you should notice that a lot of the top end ‘sparkle’ appears to be missing. Unplug your pedals and go directly to your amp, the ‘sparkle’ returns. This is because, like I said earlier, the signal has a LOT of ground to cover going through all of those cables and patch leads before it eventually reaches your speakers.
Now try the same five or so pedals but add in an extra pedal that uses a buffered bypass system, (such as the TS9). Try plugging it in, in different places along the chain, you should notice that most of your top end has remained intact, thanks to the buffer of one of the pedals amplifying the lost frequencies. Personally I like to use a buffer, or a buffered pedal, every three pedals or so. I currently have three pedals that incorporate some buffering of some kind in a chain of ten. Experiment for yourselves and find out which buffers you like the sound of, if any at all, and where in your signal you think they are appropriate or necessary.
Ultimately the decision is yours, but if you have a chain of five or more true bypass pedals then I would definitely recommend at least trying a buffer in your chain somewhere. If you are not happy using a pedal which has a buffer then why not check out some dedicated buffering circuits which can be bought, or made, reasonably cheaply by some good quality builders. I have read many opinions on buffers on the internet and one of the most popular buffers seems to be the one that is located in the Klon Centaur pedal. I have also heard that the buffers from the Arion SCH Chorus pedal sound great.
Further Reading
This is obviously just a very basic guide and a ‘for and against’ argument. There are in fact several different bypass option available to you. I recommend checking out some of these links for further reading, most of them by guys who know WAY more than I do on the subject.
http://www.gig-fx.com/products/True_Bypass_Measurement_Full_Article.pdf – This is an article by the GIG-FX team who used a frequency (spectrum) analyser to literally measure the effect that true bypass vs. Buffering can have on your tone. A good read.
http://www.geofex.com/Article_Folders/bypass/bypass.htm – A thorough article by R. G. Keen who is the chief engineer at Visual Sound. Very good read.
http://www.petecornish.co.uk/case_against_true_bypass.html – Pete Cornish’s argument AGAINST true bypass. Interesting points form a man who knows what he is talking about.