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Robert
September 28th, 2007, 07:53 AM
Is the term "true bypass" just a hype? Is the term designed to allow boutique pedal manufacturers to charge insane amounts of money for their products?

Or do you think true bypass make a huge difference?

As far as I understand it, true bypass means the signal goes from input jack to output jack via a switch, when the pedal is not engaged. It doesn't go through all the "meat and gadgetry" (the electronic parts) in there.

So if you have many pedals but you are maybe using only a couple at a time, your tone will not suffer much since the signal is bypassed through all the electronics in there on those pedals you are not using.

Then there's the all these terms you see on guitar forums. Like "virtual bypass", "hardwire bypass", etc. There's the term "buffer" and some say true bypass isn't needed if the pedal has a good buffer, etc.

I don't know enough about this stuff in order to be able to shed any light on it, so can someone step up to the plate and give us a good explanation of all this? :D (cookies for you, or maybe :pancake )

Tone2TheBone
September 28th, 2007, 08:04 AM
I dunno I believe it. Of course they make pedals way better today than they did with yesterday's components so that probably helps too. True bypass...I believe in it. Besides I like the nice modern 'click click click' you get with the new TB switches instead of the 'SHHCLUNKPOP SHHCLUNKPOP SHHCLUNKPOP' of old ones.

duhvoodooman
September 28th, 2007, 08:36 AM
Rather than attempt to explain this myself and muck it up or confuse people, instead I would refer you to THIS (http://www.muzique.com/lab/truebypass.htm) short and insightful article by Jack Orman, one of the true gurus of effects pedals. It covers both true bypass and input buffering. Just google either of those terms if you want to read more.

Pretty much all of this stuff is focused on avoiding "tone-sucking" due to loading of the guitar's pickups by low-impedance circuits connected to the signal path. In point of fact, unless you use vintage effects (like an old 70's era Cry Baby wah, which was notorious for this problem), you're unlikely to run into much of this kind of thing. Newer effects almost invariable use either true bypass or a high-impedance buffer (or both) to avoid this problem.

Spudman
September 28th, 2007, 09:05 AM
In point of fact, unless you use vintage effects (like an old 70's era Cry Baby wah, which was notorious for this problem), you're unlikely to run into much of this kind of thing.

And there is a fix for it.
I have the Thomas Cry Baby and it is really noticeable compared to the JH1 or 535Q. My tone with the mod would be much better.

http://homepage.ntlworld.com/s.castledine/greenfuz/wah.html

elavd
September 28th, 2007, 09:31 AM
Do you know Pete Cornish (http://www.petecornish.co.uk/)?

He is the man who has been making custom pedalpoards for many guitarists over the years.

His best customer is David Gilmour!!!

So take a look at his opinion about True bypass:

http://www.petecornish.co.uk/case_against_true_bypass.html

Tone2TheBone
September 28th, 2007, 09:37 AM
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.


I don't know anyone that connects their pedals with "2 foot cables". Yeah that would pretty much suck your tone. I do understand his implication though with the pedals off. He just does things a different way.

duhvoodooman
September 28th, 2007, 11:02 AM
I think he's referring to a major-league gigging rig here--a signal chain 63 feet long?? Yikes! I doubt that mine, even with my beaucoups pedals,exceeds 20' or so. And with a mix of true-bypass and high-input impedance pedals, I don't run into any of the stuff he's referring to....

Tone2TheBone
September 28th, 2007, 11:20 AM
I think he's referring to a major-league gigging rig here--a signal chain 63 feet long?? Yikes! I doubt that mine, even with my beaucoups pedals,exceeds 20' or so. And with a mix of true-bypass and high-input impedance pedals, I don't run into any of the stuff he's referring to....

I don't run into that either and I have 12 pedals all hooked up. I don't understand his comment about the 2' cables connecting the pedals. I use a 15' cable to the pedal board then about 6 of the connecting cables which are 6" long and a couple that are 1' long then a 15 footer to the amp. That's about 38 linear feet. I have no tone suck.

duhvoodooman
September 28th, 2007, 11:31 AM
Do you know Pete Cornish (http://www.petecornish.co.uk/)?

He is the man who has been making custom pedalpoards for many guitarists over the years.

His best customer is David Gilmour!!!

So take a look at his opinion about True bypass:
I'll see your Pete Cornish with my Jack Orman and raise you an R.G. Keen and an Andreas Moller! ;)

Seriously, what this points out is that there is a healthy debate on this subject with many and differing opinions even among the "experts". I think it comes down to listening closely to your signal chain and determining if you have bad things going on.

I can tell you from personal experience that with my particular mix of pedals (I currently have 12 pedals in the chain, a mix of T/B and high imped. input buffer) that I have tried pulling the cable from the guitar out of the front of the chain and plugging it directly into the amp, comparing the "before" and "after" tones. I've done this with several different pedal combinations, in different orders in the chain, and the difference in tone (to my ear, which is fairly good) ranged from undetectable to barely noticeable. YMMV....

elavd
September 28th, 2007, 11:34 AM
Seriously, what this points out is that there is a healthy debate on this subject with many and differing opinions even among the "experts". I think it comes down to listening closely to your signal chain and determining if you have bad things going on.
That's why I sold (almost) all of my 15 pedals that I used to play with , and use only my beloved TONELAB SE :Dude: :D

Robert
September 28th, 2007, 11:39 AM
What is "high impedance input buffer"?

duhvoodooman
September 28th, 2007, 01:59 PM
What is "high impedance input buffer"?
Again, rather than try to explain this in my own words, I will defer to those infinitely more learned than I--in this case, another highly respected pedal guru, R.G. Keen, who runs the information-packed Geofex.com (http://www.geofex.com/index.htm) website:


"Buffered bypass is the technique of designing a high input impedance amplifier to go ahead of the actual effect circuitry. The input impedance of this buffer is high enough to avoid tone sucking, and it has an output impedance low enough to drive the rest of the effect with no loading even if the effect proper has a low input impedance. This also allowed electronic switching from dry to effected signals, and became a favorite of several Japanese electronic companies. The best example is probably the Ibanez xx-9 series, which includes the fabled Tube Screamer 808 and 9. These effects do not get a lot of reports of tone sucking, although purists sometimes demand that they be converted to true bypass."The original TS-808's input buffer has an impedance of about 500Kohm, high enough to eliminate virtually any audible tone loss.

Robert
September 28th, 2007, 02:54 PM
So the consensus by everyone reading is that true bypass is over-hyped? (I am sticking my chicken head into the fire... or maybe I should put it in the sand :) )

duhvoodooman
September 28th, 2007, 03:06 PM
So the consensus by everyone reading is that true bypass is over-hyped?
If presented as the ONLY "right" way to wire an effect--yes.

If presented as one of several effective options for preventing tone-sucking, then no. It is popular because it is simple and unequivocally effective. Circuits that are physically disconnected from your signal path--and that is the essence of what T/B is all about--cannot possibly suck your tone.

To me, a more interesting discussion is on the various "flavors" of true bypass that are sold out there, some honestly and others with a clear intent to misrepresent/defraud. My favorite is "virtual true bypass". Now what the heck is THAT supposed to mean?? I have a pretty good idea what "virtual truth" is--and it's a staple of American politics!! :rolleyes:

SuperSwede
September 29th, 2007, 12:34 AM
This is what tech21 has to say about true bypass:

http://tech21nyc.com/tech_notes/technotesFrameset.html

333maxwell
October 2nd, 2007, 02:14 PM
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.


I don't know anyone that connects their pedals with "2 foot cables". Yeah that would pretty much suck your tone. I do understand his implication though with the pedals off. He just does things a different way.

I was thinking just like you when I read it.. 2 ft patch cords etc.. seemed like skewering the numbers to make a point..

Spudman
October 14th, 2008, 11:28 AM
Here is a great explanation of True Bypass and buffer interaction.
http://www.muzique.com/lab/truebypass.htm

Ch0jin
October 22nd, 2008, 11:24 PM
And there is a fix for it.
I have the Thomas Cry Baby and it is really noticeable compared to the JH1 or 535Q. My tone with the mod would be much better.

http://homepage.ntlworld.com/s.castledine/greenfuz/wah.html

Sorry Spudman but I wanted to clarify your comment.
You say your tone with the mod "would be" much better. So you haven't tried the mods from that link?

If you have I'd love your feedback because I have done most of those mods (I didn't change the inductor) on a 18yo JD Crybaby and that pedal went from "used regularly" to "lying in a pile of bits in a box" after the mods. I won't go fully OT and mention why its in pieces now, but suffice to say after mods it sounded awful and I haven't had the time to re-engineer it to more acceptable "Chojin-Spec".

Anyway, regarding Tru Bypass, yeah, crybaby wah's are a massive tone sucker muddying your highs very obviously. That's the only pedal I've used that does though. My BOSS OD's seem fine and all my home-mades are true bypass anyway.

Regarding long cable runs and the -downsides- of true bypass that have been mentioned, wouldn't it make more sense at the pro level to use a buffer/booster pedal at the start and finish of your chain than use FX that you know will tarnish your tone? I mean, if your pickups need to be impedance matched to your first pedal, then make that pedal a buffer that does not colour your tone. Ditto your amp input. If your tube amp works best at a specific input impedence, make a buffer that matches it. Then whack whatever you like in between as long as it's true bypass and off you go.

So anyway...

FWIW I reckon some FX need true bypass and some don't, but there are sooo many variables, not least of which is what you think sounds good.

markb
October 23rd, 2008, 02:32 PM
And here's Visual Sound's Bob Weil on the subject.

Do Visual Sound pedals have "true-bypass"?
No, but for some very sound reasons. And they have something which may be better: Pure Bypass.
First, the switches required for "true-bypass" are far more expensive than ours and are less reliable in the long run. This would make our pedals in the $200+ range (list price) and they wouldn't last as long. Our unique electro-mechanical switching system with heavy-duty switches and a "switch chip" should last a good long time.
Secondly, the buffering system in the pedals was taken from our Pure Tone pedal. This pedal was built originally for guitarist Neil Zaza who needed something to clean up his bypass tone for all the pedals he used (VOX wah included). Pure Tone, when placed first in the chain, made it sound like you were plugged straight into the amp even when going through notorious tone killer pedals. We ended up selling about 200 of these to very happy tone conscious guitar players before we put it into Jekyll & Hyde as an added feature. So, if J&H or Rt. 66 is first in your chain, it will buffer everything that follows it as well as itself. Even if it's in the middle of the chain, it will still work to some extent.
Thirdly, the Pure Tone buffer also keeps the Hyde circuit (in Jekyll & Hyde) stable. In the early stages of design, I noticed that the Hyde circuit was prone to occillation and feedback until I put the Pure Tone circuit before it. Somehow, it left all the good characteristics in tact and eliminated the ugliness.

A clean, well designed buffer is no bad thing. If only Jim Dunlop could build one as chojin says above. Crybabies are the suckiest things on earth. On the whole I've had no problems with chains of Boss pedals and used to have an MXR Phase 90 that actually seemed to improve the signal when using two 6m cables.

Jimi75
October 24th, 2008, 05:43 AM
don't want to get to scientific on that topic. I can only describe what I my ears tell me and I have pedals that are not in my live set up because they suck sound due to the fact that they are not true bypass. For example my Dunlop Univibe - had to remove it from the effects chain.

My Wah pedal had been modded to TB, also my Ibanez TS9. If the pedal is not engaged/on I want to have the pure sound between my guitar and my amph.

To me it is no hype. Future buys will be TB, otherwise I do not buy the pedals.

ZMAN
October 26th, 2008, 07:16 AM
All I can say Robert is that I use Fulltone pedals exclusively and I went with them because they are so quiet for one thing and are true bypass. I have Boss, and Tube Screamers that are in the cupboard.
This is what Mike Fuller has to say about his pedals and true bypass.

"We use True Bypass switching (with L.E.D. status indicators) in all our pedals, whenever possible. Most other pedals have a buffered output that destroys the performance of most pedals that follow in the signal-chain. Don't be fooled by the claims of "Pure Bypass," "Hard Bypass"...etc. These are just catch phrases to divert your attention away from the fact that those pedals are not true-bypass. I designed and manufacture the Fulltone 3PDT , the world's only Super-Duty Triple Pole Double Throw footswitch"

It goes on to mention how it was designed etc. but I thought if you want to read it all you can go to his web site. I am totally pleased with the performance of them and I am saving my pennies to upgrade to a Clyde Deluxe wah.