True Bypass - Just Say Perhaps

[Hemisaurus]

Nice counter argument against true-bypass. http://www.petecornish.co.uk/case_against_true_bypass.html

The "true bypass" function, which is promoted by some, can create dreadful problems with a system that uses many pedals. Take for instance a 15 ft guitar cable linked to ten pedals, each linked by a 2 ft cable, and then onto the amp by a 30 ft cable. If all pedals have "true bypass", and are off, then the total cable length hanging on the guitar output will be 63 ft. This will cause a huge loss of tone and signal level particularly if the guitar is a vintage type with low output and high impedance. The amp volume is then turned up and the treble control increased to compensate for the losses. The inherent background noise now increases by the amount of the gain and treble increase and is usually, in my experience, too bad for serious work. If one of the pedals is now switched on, then it's (hopefully) high input impedance (and usually low output impedance) will buffer all the output cables from the guitar and the signal level will rise due to the removal of some of the load on the pickups (i.e.: 17 ft instead of 63 ft of cable). The treble will rise and the tone and volume will not be as before. If that pedal was say a chorus or delay, devices which are usually unity gain, then your overall signal level and tone will vary each time an effect is added...not a very good idea.

Some pedals have an input impedance which is far from high in real terms; the input impedance of the vast majority of amps is 1 Megohm (one million ohms) and in my experience there are few effects pedals that have the same input impedance. A load on the guitar of less than 1 Megohm will reduce the volume and high frequency content of the pickup signal thus giving rise to complaints that "this pedal looses tone/volume" etc. Many effects I have tested have an input impedance of less than 100 Kilohms (ie: only one tenth of the amp input impedance) and cause serious signal losses in the effects chain.

My system, which I devised in the early 70's, is to feed the guitar into a fixed high impedance load, which is identical to the amp input, and then distribute the signal to the various effects and amps by low impedance buffered feeds. This gives a constant signal level and tonal characteristics, which do not change at all when effects are added. The proof that this works are in the recordings of our clients: Roxy Music; The Police; Queen; Pink Floyd; Bryan Adams; Lou Reed; Dire Straits; Paul McCartney; Sting; Jimmy Page; Judas Priest; Black Sabbath....

So the answer to your question re "true bypass" is no, I do not use this system in my Effects Boards/Racks as it can seriously degrade your sound. All my current effects pedals (excluding Vintage Series) which are derived from our large systems have, as the main input stage, a fiendishly clever pre amp that has the same characteristics as the input of a tube amp (1 Megohm/20pF), a highly efficient filter to eliminate the possibility of radio breakthrough and a low output impedance so that any following pedals/ cables etc. will not impose a load on the guitar signal. This pre amp is fitted to all our large stage systems and has always met with huge approval; not only from the guitarist but also the PA operator who is so happy to have constant level and tone presented to his mixing board. I go further with large systems and provide several inputs, each with the isolating pre amp and a gain compensation pre amp so that many different guitars can be level matched into the system. In addition a 20 segment PPM type display provides visual indication of signal level in our Effects Boards and Rack Systems.

[rayinreverse]

I'm sure cornishes argument works great for ultra mega guitar players he works for. It's a good argument,but only holds water for huge rigs with massive cable runs

[spookstrickland]

Yes and No

If all your pedals are buffered pedals as well you will be causing micro amounts of distortion and tone sucking for every one that is engaged.  What you want is:

To have all of your pedals be True Bypass except the first pedal in the Chain to be buffed.  That's all you need.  And that's pretty much what Pete is talking about except he want's to sell you a super expensive board and buffer when all you need to do is run a simple cheap boss pedal first then all of your sweet True Bypass boutique pedals after it and you will be just fine.

[Baltar]

Exactly, you nailed it Spook.  I'm only running 4 pedals right now, all 3pdt,  no buffer, but my wah is bright, Tonebender is bright, amp is bright.  I end up turning down the treble.  Kevin Shields from My Bloody Valentine runs like 50 pedals, two of 'em are Cornish, so he needs some buffers.

[Hemisaurus]

Actually, he cocked it up slightly, he forgot to add the insertion loss of each connector. Every connector has a certain amount of loss involved in it, even the best contacts, so 2 x 20ft cables with a pedal in the middle have more loss than a 40ft cable. Every connection will degrade your signal, whether bypassed or buffered.

I suppose the best way to do it would be, if you know your pedalboard won't change, hardwire the pedals together in a case a la Cornish. You'll still have cable losses internally, but they'll be less than the combined connector losses.

Also note he specifically mentions vintage guitars, those with modern higher output humbuckers are going to be less affected.

I'm not advocating one way or another, far too tweaky for me

[spookstrickland]

Actually, he cocked it up slightly, he forgot to add the insertion loss of each connector. Every connector has a certain amount of loss involved in it, even the best contacts, so 2 x 20ft cables with a pedal in the middle have more loss than a 40ft cable. Every connection will degrade your signal, whether bypassed or buffered.

I suppose the best way to do it would be, if you know your pedalboard won't change, hardwire the pedals together in a case a la Cornish. You'll still have cable losses internally, but they'll be less than the combined connector losses.

Also note he specifically mentions vintage guitars, those with modern higher output humbuckers are going to be less affected.

I'm not advocating one way or another, far too tweaky for me

That's a good point Hemi about the connector loss that's something that you just don't hear much about anymore but is a real problem.  I guess you would need gold plated plugs and jacks to minimize the lose or some sort of a new fangled connector or to hardwire them like you mentioned.  It would take some pretty big balls to hard wire you pedal board! especially with rare or vintage effects.

[Hemisaurus]

I actually though it was more of a good save for cheap FX. Look at the pedalboard he did for Julian Cope.



Those look kinda like standard Boss pedal knobs, I've been looking at parts places this evening trying to source buttons like that. You can take your cheap FX out of it's plastic box, mount it on the casing where the knobs are protected, and just remove the cheapo microswitch and hook it to the giant push button. I've got an old DOD delay, and a pair of Behringer pedals that would benefit from a transplant. Maybe fling in my old Flanger or get another Behringer.

Maybe I can figure out some kind of switching matrix, if I want flexibility. Anyways something else to add to the project pile.

[bitter]

That looks like military Equipment or something. Kinda like someone pulled an electronics panel out of a tank! 

[Hemisaurus]

Well the pedal looks like a Morley, and the phase, delay and turbo look like Boss. The rest is probably the built in preamp / mixer, if you look at other views of it on his website it has a whole bunch of output options and such.

[VOLVO)))]

Watch that fuzz documentary, There's many big time builders saying it's just a marketing ploy...

[spookstrickland]

The other good thing about true bypass is if the battery dies or the pedal fucks up some how in the middle of a show you just click it off and you are good to go.  If it's not true bypass your signal dies along with the pedal.

[moose23]

More good reading on bypass:

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

[Hemisaurus]

I was surprised by the variance of input and output impedances of Boss's pedal range, I think the DS-1 must be a misprint, 470 ohm input impedance, I think someone may have dropped a K from the spec sheet, but even so, some are 1M in 10K out, some are 470K in 1K out, etc. etc.

Like vintage mic's impedance has more effect on low output pickups, which tend to be either vintage, or vintage cloned, so people rocking DiMarzios, or Seymour Duncans, or heaven help them EMG's have less to worry about.

[Instant Dan]

No I want to run all true bypass! Especially with my Klon Centaur into my Dumble amp and 59 burst while I play Mustang Sally at the local bar and grille.

[RacerX]

Eh, my rig makes such an unearthly racket that no one's gonna hear the difference.

I run my TU-2 first in the chain anyway, so I'm covered.

[clockwork green]

Damn! And I thought that some of my pedals actually sound pretty good...I guess I was wrong.

That article has been around for a long time. The new thing blues lawyers are doing now is going all true bypass and adding a buffer. Buffers have issues, true bypass has issues, there are no absolutes.

[spookstrickland]

The switches that most pedal builders use that they say "pop" in the article can either be fixed by a pull down resistor or you can wire them up so that when switched out the input and output caps are grounded which works even better.

I think that the Techno Nerds with the money are just trying to steer pedal buyers away from the little guy doing business in his basement because to do the switching they are talking about is going to ad more time and more money to each build and in doing so increase the price and pretty soon the little guy will no longer be competitive.

[Pundan]

I've heard this before, seems it's harder to get a pedal without true bypass these days. But what you're guys basically are saying is that if you run a tuner pedal first in your chain it should be pretty cool to have true bypassed pedals after it? I can't say that I've really heard a difference from all pedals I have (I have an old 80's ROSS Distortion that's not true bypass).

[grimniggzy]

I've heard this before, seems it's harder to get a pedal without true bypass these days. But what you're guys basically are saying is that if you run a tuner pedal first in your chain it should be pretty cool to have true bypassed pedals after it? I can't say that I've really heard a difference from all pedals I have (I have an old 80's ROSS Distortion that's not true bypass).

Actually, people where talking about running a buffered bypass pedal (Boss for example) first in the chain.
I have the Korg Pitchblack Tuner which is true bypass but run a Boss OC-2 first in my chain to get the strongest signal from my bass for tracking reasons anyway.
Truthfully I heard no audible difference when I switched them around. But my setup is a little noisy to begin with.

[Pundan]

I've heard this before, seems it's harder to get a pedal without true bypass these days. But what you're guys basically are saying is that if you run a tuner pedal first in your chain it should be pretty cool to have true bypassed pedals after it? I can't say that I've really heard a difference from all pedals I have (I have an old 80's ROSS Distortion that's not true bypass).

Actually, people where talking about running a buffered bypass pedal (Boss for example) first in the chain.
I have the Korg Pitchblack Tuner which is true bypass but run a Boss OC-2 first in my chain to get the strongest signal from my bass for tracking reasons anyway.
Truthfully I heard no audible difference when I switched them around. But my setup is a little noisy to begin with.

Cool, thanks! I'm kind of retarded when it comes to this shit.

[grimniggzy]

I've heard this before, seems it's harder to get a pedal without true bypass these days. But what you're guys basically are saying is that if you run a tuner pedal first in your chain it should be pretty cool to have true bypassed pedals after it? I can't say that I've really heard a difference from all pedals I have (I have an old 80's ROSS Distortion that's not true bypass).

Actually, people where talking about running a buffered bypass pedal (Boss for example) first in the chain.
I have the Korg Pitchblack Tuner which is true bypass but run a Boss OC-2 first in my chain to get the strongest signal from my bass for tracking reasons anyway.
Truthfully I heard no audible difference when I switched them around. But my setup is a little noisy to begin with.

Cool, thanks! I'm kind of retarded when it comes to this shit.

"anytime"

[spookstrickland]

Here is good article on truebypass

http://www.muzique.com/lab/truebypass.htm

And this guy really knows his shit too!

[eyeprod]

it seems that the deal with the pete cornish pedal rigs is that he re-houses the players particular pedals in his own heavy duty enclosures. He's re-wiring most of the stuff, in particular he mentions separating the circuit board and controls from the switches. That's why you see parts of the pedal in some recessed cavity and those big ol' foot switches he uses. Basically he makes a bulletproof, low profile enclosure with good grounding and a shit load of custom options. People who buy that shit and don't play pro are lame. I respect his concepts and build quality though. Not a bad idea at all to focus on interesting full enclosures rather than building clones of classic circuits or trying to invent new ones.

as for the buffer thing. I've got mostly true-bypass pedals except some boss stuff. I usually run the tuner in front anyway, but tried taking it out of the chain. I could tell a bit of difference for sure. In my rig, the signal was a little stronger with the boss pedal at the front of the chain.

[Hemisaurus]

Not all buffers are created equal, just to mess with peoples heads some more.

I imagine some of the more reactive pedals, certain wah's and fuzzes that are famed for interacting with the pickup impedance, are possibly best pre-bypass? Not owning any of that vintage stuff, I can't tell you for sure.

[spookstrickland]

Not all buffers are created equal, just to mess with peoples heads some more.

I imagine some of the more reactive pedals, certain wah's and fuzzes that are famed for interacting with the pickup impedance, are possibly best pre-bypass? Not owning any of that vintage stuff, I can't tell you for sure.

For the Fuzzes you actually have to use a Transformer to simulate your pickup impedance if you place it in the middle of a buffered chain.  I've experimented with it and while it's not perfect there is some improvement if you want to take the time and really get picky with it.