Somebody tell me what "true bypass" means...

[cazksbass]

I'm looking for a good, simple, no-frills A/B box to switch my Fender from (A) into my rack tuner to (B) into my amp. I been noticing a lot of bragging that some boxes are "true bypass". What does that mean? I'm fairly electronics-savvy, so if anybody is a whizkid don't be afraid to get all technical on me.

Thanks in advance...

[ShowKing]

true bypass basically means the tuner, when in the chain between ur bass and amp, will not alter ur tone in any way

[bigchiefbc]

Originally Posted by ShowKing

true bypass basically means the tuner, when in the chain between ur bass and amp, will not alter ur tone in any way

The commonly accepted definition of true bypass in the effects world is usually taken to mean that when the bypass switch is pressed, the input is connected directly to the output, and the circuit in the pedal is physically disconnected from the signal path.

[cazksbass]

Originally Posted by ShowKing

true bypass basically means the tuner, when in the chain between ur bass and amp, will not alter ur tone in any way

Hmm, thanks...but I was referring to the maker of of an A/B box making the claim that their box is "true bypass" or not. Interestingly, you've nailed my situation exactly. I currently run my bass into my Korg rack tuner (D-1000) and take the tuner's out straight into my amp. But what I want to do is to run my bass into an A/B box first so I can stomp it to choose the tuner or the amp.

Originally Posted by bigchiefbc

The commonly accepted definition of true bypass in the effects world is usually taken to mean that when the bypass switch is pressed, the input is connected directly to the output, and the circuit in the pedal is physically disconnected from the signal path.

AHA! That's what I was after. So...you mean that a "true bypass" switching device is one that physically disconnects from the alternate signal path? OK, I can now easily see why that would back up a claim that it won't alter your tone. But...that implies that other switching devices that are not true bypass do not physically disconnect from the alternate signal path. Is that right? Am I missing something? Clearly, I would choose true bypass over "non-true bypass" any day...

[Implosion]

A good read about true bypass

http://www.tech21nyc.com/technotes/index.html

[cazksbass]

Originally Posted by Implosion

A good read about true bypass

http://www.tech21nyc.com/technotes/index.html

Ahhh...thanks. That looks like it teach me a lot...

[DreadRaver]

That Tech21 article does not cover every type of true bypass system.
For instance, Cusack Music's True Bypass Switching system incorporates a telecommunications relay, which offers the absolute cleanest signal path and has the advantage of staying in bypass if your battery dies.

[bigchiefbc]

Originally Posted by cazksbass

AHA! That's what I was after. So...you mean that a "true bypass" switching device is one that physically disconnects from the alternate signal path? OK, I can now easily see why that would back up a claim that it won't alter your tone. But...that implies that other switching devices that are not true bypass do not physically disconnect from the alternate signal path. Is that right? Am I missing something? Clearly, I would choose true bypass over "non-true bypass" any day...

That is correct, most non-true-bypass pedals do not physically disconnect the circuit from the signal path. The most common of these (such as those used by Boss pedals) are usually referred to as "buffered bypass". But this is not always a bad thing. Remember that a long string of true bypass pedals is basically just like a long cable. So if you have a long cable going into the pedalboard, and then a long cable between there and the amp, you could potentially end up with what is basically a single REALLY long cable, and this can also degrade your signal. A good buffer in your signal chain can prevent that issue from popping up.

[cheapbasslovin]

The merits of true bypass versus buffered are debatable and vary largely on the quality of buffer used.

A third type that you'll see called 'true mechanical bypass' among other things is actually output bypassing. This means that a switch connects your input directly to the output (disconnecting the output from your pedal circuitry), but leaves the input circuitry electrically attached to the signal circuit. True bypassing as described by Bigchief is undeniably better than this output bypassing. This can add load to the circuit and will likely cause some tone suck. Most older EHX and (to my knowledge) MXR pedals work this way.

[Jared Lash]

True bypass is very similar to "True Romance" except instead of Christian Slater you have Burt Reynolds.

[Smurf-o-Deth]

So, true bypass lets me go bandit?

[cazksbass]

OK, now I think I'm over my head. I thought I wanted to learn all the technical stuff but it just makes my head hurt . The Tech21 article was good but then one of youse guys said it doesn't cover all of the buffering schemes.

Maybe I should just cut to the chase and ask what's the best A/B box for my passive Fender bass. Should I make a new thread for that or not?

[gnasher1993]

True bypass means that when the effect is bypassed, the fragile harmonics in the crystal lattice are retained and no tone loss can be heard.