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View Full Version : Symmetrical vs Asymmetrical Clipping


hdahs143
03-12-2009, 02:06 PM
As the title says, say using the same diodes in the same circuit, is there a noticeable difference between the two?

What are some of your favorite combinations?
I have had a BYOC screamer for a couple of years and feel like experimenting.

ianb
03-12-2009, 03:22 PM
I would also be interested in more info on this point!

Thanks.

BrianWampler
03-12-2009, 03:46 PM
depends on the circuit and what configuration... for example in a ds-1 it's pretty noticeable, quite a bit so in the tubescreamer variants as well...

orogeny
03-12-2009, 06:15 PM
depends on the circuit and what configuration... for example in a ds-1 it's pretty noticeable, quite a bit so in the tubescreamer variants as well...
indeed. i only use my ears! this guy knows his shizzle like beans know the rice though. . . .

tjmicsak
03-12-2009, 08:34 PM
With asymmetrical clipping your hair will be longer on one side than the other.

KBN
03-12-2009, 10:21 PM
With asymmetrical clipping your hair will be longer on one side than the other.

http://4.bp.blogspot.com/_-HbIhXnhtrU/SU4sYXX6PNI/AAAAAAAABIQ/rjYQu_h8NhI/s400/BadHaircut.jpg

aziltz
03-12-2009, 10:28 PM
http://4.bp.blogspot.com/_-HbIhXnhtrU/SU4sYXX6PNI/AAAAAAAABIQ/rjYQu_h8NhI/s400/BadHaircut.jpg
looks like he's been punched in the eye... ouch...

sodapopinski
03-12-2009, 11:59 PM
symmetrical sounds smoother and not as grainy... i was playing with the dip switches in my Timmy today and i liked symmetrical clipping the best

soulsonic
03-13-2009, 12:16 AM
I think Asymmetrical is the most fun sounding.

tookermel
05-14-2009, 10:23 AM
Which way is which?

I bought my Timmy used, and don't have any instructions...

I did a Yahoo search, but didn't find anything, and was gonna post in the effects forum, but did a quick search and came across this post.

I finally took the back off of my Timmy last night and actually saw two switches. I expected to find one switch - one way's asym, the other sym...

With these two switches, there is a 1 on one side, and a 2 on the other. Why are there two switches, and which ones do what?

Thanks in advance!
-Tookermel

Jack
05-14-2009, 10:45 AM
On the timmy, when both switches are in the same spot, it's symmetrical, but the difference will be compressed vs. open. When you turn one switch opposite the other it's assymetrical, but it doesn't matter which switch is up and which is down.

I like symmetrical better. I have an Analogman SD-1 (808 specs) that has a push/pull for clipping. Stock SD-1 is asymmetrical and TS is symmetrical. I find that I like symmetrical better with the AM SD-1 and the timmy. Haven't really been able to a/b those 2 modes in the same pedal much. Asym is more aggressive as someone said above.

Amp clipping is asymmetrical, so it seems like whether you feed an amp sym or asym, your net result is going to be asym. It may be a different ball game if your amp is really clean. My amp is not clean, and giving it asym is like piling on the mud. The sym is clearer, smoother, more articulate, less muddy.

I wonder if giving the clipping amp asym is making too much asym or something. It seems like the degree of asym is going to be an issue too.

Each type is supposed to be more concentrated in even/odd harmonics respectively, but I can't remember which does which.

amz-fx
05-15-2009, 05:24 AM
As the title says, say using the same diodes in the same circuit, is there a noticeable difference between the two?

What are some of your favorite combinations?
I have had a BYOC screamer for a couple of years and feel like experimenting.

There is a noticeable difference for a couple of reasons:

(1) The symmetrical clipping has only odd harmonics. This produces a a woody, hollow sound (which is dramatically altered by the tone control). Cuts through a dense song quite well.

(2) Asymmetrical clipping produces both even and odd harmonics, which adds some depth and a certain smoothness to the sound... some say tube-like.

(3) Asymmetrical will be louder for the same input signal, because one-half of the signal is clipped at a higher level. This should be immediately noticed by any user.

Both options have their uses, and can be interesting.

regards, Jack

Franklin
05-15-2009, 06:19 AM
If you can get a couple of sockets for the diodes and try mixing and matching them to see what you like.

jpagey
05-15-2009, 07:18 AM
Jack's the man.

StompBoxBlues
05-15-2009, 02:10 PM
There is a noticeable difference for a couple of reasons:

(1) The symmetrical clipping has only odd harmonics. This produces a a woody, hollow sound (which is dramatically altered by the tone control). Cuts through a dense song quite well.

(2) Asymmetrical clipping produces both even and odd harmonics, which adds some depth and a certain smoothness to the sound... some say tube-like.

(3) Asymmetrical will be louder for the same input signal, because one-half of the signal is clipped at a higher level. This should be immediately noticed by any user.

Both options have their uses, and can be interesting.

regards, Jack

This is interesting, but I have to admit...I'm not quite sure how you are referencing that point #3.

Just to be sure we're all on the same page. Symmetrical means simply that the AC wave, which goes above 0 volts, and below zero volts, does to "evenly" meaning if the peak voltage above is at 1 volt the peak at negative swing of the sinus wave is also at 1 volt.

Asymmetrical means that if the positive swing of the signal goes to 1 volt, the negative might go to .7 volts, or something like that.

That said, when you say "Asymmetrical will be louder for the same input signal, because one-half of the signal is clipped at a higher level" I'm wondering how you "measure" that. Are you using the smaller part of the asymmetrical clip vs. the symmetrical or the larger (positive going for example) peak to measure against?

schenkadere
05-15-2009, 02:38 PM
There is a noticeable difference for a couple of reasons:

(1) The symmetrical clipping has only odd harmonics. This produces a a woody, hollow sound (which is dramatically altered by the tone control). Cuts through a dense song quite well.

(2) Asymmetrical clipping produces both even and odd harmonics, which adds some depth and a certain smoothness to the sound... some say tube-like.

(3) Asymmetrical will be louder for the same input signal, because one-half of the signal is clipped at a higher level. This should be immediately noticed by any user.

Both options have their uses, and can be interesting.

regards, Jack

I'm curious...I have an SRB808+ which has a switch for asymmetrical/symmetrical clipping. The asymmetrical has a significant volume drop although higher gain. Maybe it's just the design? It's supposed to be that way...it's not faulty. That seems opposite of what you state above. I wonder why?

Tone_Terrific
05-15-2009, 03:25 PM
I'm curious...I have an SRB808+ which has a switch for asymmetrical/symmetrical clipping. The asymmetrical has a significant volume drop although higher gain. Maybe it's just the design? It's supposed to be that way...it's not faulty. That seems opposite of what you state above. I wonder why?

If you clip more the volume decreases.
If you have more gain the volume increases unless it is clipped.
Gain=volume, not distortion, unless something, like a clipping diode, is overdriven. Overdrive creates distortion.

schenkadere
05-15-2009, 05:54 PM
If you clip more the volume decreases.
If you have more gain the volume increases unless it is clipped.
Gain=volume, not distortion, unless something, like a clipping diode, is overdriven. Overdrive creates distortion.

Gotcha...thanks.

brian marshall
05-15-2009, 10:12 PM
There is a noticeable difference for a couple of reasons:

(3) Asymmetrical will be louder for the same input signal, because one-half of the signal is clipped at a higher level. This should be immediately noticed by any user.


This totally depends on how it is implemented. you could have several diodes and have symmetrical clipping.... certainly if you add a diode it will be louder, and asymmetrical.... but you could also remove one and have asymmetrical clipping.

My personal opinion is that asymmetrical clipping (at least with diodes) has an ungraceful transition from clipping to not clipping as the signal dies off... especially in a TS feedback loop type set up.

StompBoxBlues
05-16-2009, 02:55 AM
This totally depends on how it is implemented. you could have several diodes and have symmetrical clipping.... certainly if you add a diode it will be louder, and asymmetrical.... but you could also remove one and have asymmetrical clipping.

My personal opinion is that asymmetrical clipping (at least with diodes) has an ungraceful transition from clipping to not clipping as the signal dies off... especially in a TS feedback loop type set up.

Which theortically maybe makes some sense...I mean when both directions of the wave are clipping that is one thing, but when you have the positive side of the wave clipping, but the negative not reaching the clip threshold...

Symmetrical they will both reach that point together...

Also, when folks mention "amp-like" I wonder how many amps out in the world are biased to asymmetrical also?
Theoretically they ought to be biased symmetrical for smooth transition between pos and neg sides of the cycles, but
in reality no two tubes are 100% the same, so you probably have anywhere from "some" to "a lot" of asymmetrical clipping when pushed.