Overdrive pedal gives my guitars "ahWwWw" sound

[ViolenceOnTheRadio]

It's very desirable, I'm just wondering exactly what is occurring that causes this effect.
It's somewhat like a wah but more of an ahwWwW. I know some pickups naturally do this since I have a handful but the overdrive I've been working on and modding the last several years now causes every guitar to do it or just intensifies it after my most recent mods.

Is it simply an effect caused by the frequency curves of the different pieces of equipment/stages in my rig and the signal flexing and shifting around as it travels through the cascade?
The frequency curves of my pedal, preamp, power amp and speakers are intensely different.
I get it most with the bass on the pedal at 50% or greater and the treble/midrange control at 30% or less and then vice versa does it as well. One result being more midrange and treble flexing, the other being bass dominant and making the notes sound like they're flabbing around.
Surely there is a legendary term for this...have I achieved the brown sound!?

[petemoore]

I'm just wondering exactly what is occurring that causes this effect
 You guessed it !
  The combined 'effects' I don't have a schematic for any of it, but it varies by player anyway.

[ViolenceOnTheRadio]

I have a theory on how it's done with humbuckers.
A matched set of coils only the trick I suspect is, using different wire gauges on each coil.
So you produce the same impedance but different peak resonant frequencies which gives a nice "ahw" due to the difference in the peak resonance frequencies interacting with one another ultimately creating an active rippling in the pickups overall frequency curve.

[FiveseveN]

What is a "frequency curve" and why would it have ripples?
Are you talking about comb filtering/general variance in the context of a frequency response (i.e. "spectrum") or phase shift in one or more components of the signal (i.e. "waveform")?

[amptramp]

See if you get this sound without any pedals in the way, just guitar to amp.  Some tube amplifiers exhibit "gulp" distortion where the input signal going into the input stage overloads the grid-to-cathode diode in such a way that it conducts and increases the grid bias.  This causes the signal to partially or completely disappear until the time constant of the coupling capacitor and grid resistor allow enough of the added DC to bleed off and permit normal operation again.  If it is not happening in the ampifier, it could be happening in one of the pedals in some stage where amplifier bias could be shifting as a result of the input signal.  Do you get this effect at all levels or only when it is played loud?  After trying it out with just the amp, add pedals until you get the effect.  The last pedal added would then be the culprit.

[wavley]

Do you get this effect in different rooms?  We could also be talking about room nodes/nulls/anomalies.

[ViolenceOnTheRadio]

What is a "frequency curve" and why would it have ripples?
Are you talking about comb filtering/general variance in the context of a frequency response (i.e. "spectrum") or phase shift in one or more components of the signal (i.e. "waveform")?

I'll bite even though I know your question was probably an attempt to annoy me....
"Frequency Curve" is a very common term regarding anything to do with audio and surely you know this based on the references you made. Frequency response means the exact same thing but Frequency curve is a far more common and general term since it applies to other contexts.
It is a spectral analysis of the frequencies a device can produce, reproduce or transmit.
I should have used the word rippling so it was a verb. Similar to a wah, you're getting a peak resonance frequency that is shifting. In the case of pickups however, your frequency curve is constantly shifting from the note decaying if you allow it to sustain, from vibrato or it's shifting as you play through different notes. When this occurs, you have a rippling effect in the overall frequency curve produced by the pickups because there are two distinct signals traveling on the same path and interacting with one another.

So I suppose yes, it's phase shifting but there's a bit more to it than that. Without the different frequency curves of each coil, the phase shifting really wouldn't be audible which is why not all pickups produce this effect  even though a humbucker's coils are wired out of phase. It's more of timber effect and the frequency shifts of the coils interacting with one another. So if you wind two coils to the same impedance to build a humbucker but with different gauge wire so the frequency curves are different, you should get that rippling wahing sound from the phase shifting.
Like when you wire two pickups out of phase say in position 1 and 2 on a strat. You suddenly produce a HUGE spike and shift in peak resonant frequency and you hear the shifting in the two pickups meeting to produce that new peak  which produces a "wahing" sound.  
It's rippling though you can feel free to reject this terminology.

Amptramp, I think I may be achieving a similar effect to what you're explaining in an amp, in my pedal. As basic as it is, I've placed a resistor before the master volume pot. Depending how hard you pick, there is a varying level of limiting taking place on the signal so you hear the shift as signal is retarded and advanced across the resistor. Adjusting the master volume varies as well as bypasses this effect. The EQ also adds to this by increasing resistance to the bass and treble/mid controls.
This is why I've used the term rippling.

To wavley, I get this effect even through headphones.
It's in the signal itself though you raise a good point, the right architecture of a room will certainly produce this effect.

[stringsthings]

It's very desirable, I'm just wondering exactly what is occurring that causes this effect.
It's somewhat like a wah but more of an ahwWwW. I know some pickups naturally do this since I have a handful but the overdrive I've been working on and modding the last several years now causes every guitar to do it or just intensifies it after my most recent mods.

Is it simply an effect caused by the frequency curves of the different pieces of equipment/stages in my rig and the signal flexing and shifting around as it travels through the cascade?
The frequency curves of my pedal, preamp, power amp and speakers are intensely different.
I get it most with the bass on the pedal at 50% or greater and the treble/midrange control at 30% or less and then vice versa does it as well. One result being more midrange and treble flexing, the other being bass dominant and making the notes sound like they're flabbing around.
Surely there is a legendary term for this...have I achieved the brown sound!?


no.  you have not achieved the brown sound.

[ViolenceOnTheRadio]

Yeah I don't think the brown sound is all that difficult to achieve anyway...or all that interesting   

[petemoore]

  Synergy ?
  Of course...when it all works together and there's a special magic tone that defies the exact application of adverbs ?
  "Chain resonance"...effect. All of a sudden certain frequency bands 'ring' or shudder or make some other pleasing phenomenon.

[stringsthings]

Yeah I don't think the brown sound is all that difficult to achieve anyway...or all that interesting   

what do you find interesting? or difficult to achieve?

[ViolenceOnTheRadio]

I did some more work and it turns out to be a dampening effect giving me this "ahwWw" or "yahwWw" sound. With the volume set just right, a lot of notes shift in frequency output in response to the resistance on the load. Put more simply, as the note swells in volume or decays, there is a large shift in which frequencies are passing across the volume pot.
Maybe call it reactive frequency dampening?
I have a loooot of weird filters in this pedal so I suspect it is partially due to what Petemoore called chain resonance and by dumb luck the volume pot set to the right resistance gives a dampening effect where the load causes this chain of variant resonance to shift the peaks so they advance or retard in response to the resistance.

I suppose this is what all the drama surrounding tubes is largely about because this is an effect I have always noticed primarily with tube amps. Some are so finely tuned to produce this dampening frequency shift that they sound like they have a mild envelope filter running on them.

[ViolenceOnTheRadio]

Figured I'd go all the way and share audio of the circuit performing. I'm getting a nice groggy, waking up/dozing off response. This is recorded direct so it lacks the further dynamics added by my 4x12 cabinet. I've added a pot to control the dampening factor rather than relying on the master volume.

http://www.supload.com/listen?s=9ht4fx

I just need to change a capacitor so I have more midrange running through the circuit and the performance should be improved 10 fold.
Amazing what resistance and filtering can accomplish, this is a purely solid state op amp driven rig!

[stringsthings]

Yeah I don't think the brown sound is all that difficult to achieve anyway...or all that interesting   

you seem to be avoiding the issue.  what is it that you find difficult to achieve?  or do you simply enjoy making light of a famous amp sound?

[modsquad]

Oh no not this debate.   I have seen it on so many forums and it never turns out good....

The "Brown Sound" is really relative.   My point is that it depends on your ears.   I think its easy to get with some EQ, BSIAB and echo.   But you may think it sounds nothing like your definition of "THE" Brown Sound.   But for me it works.

[CynicalMan]

The "Brown Sound" is really relative.   My point is that it depends on your ears.   I think its easy to get with some EQ, BSIAB and echo.   But you may think it sounds nothing like your definition of "THE" Brown Sound.   But for me it works.

Or your bowels? 

[ViolenceOnTheRadio]

Yeah I don't think the brown sound is all that difficult to achieve anyway...or all that interesting   

you seem to be avoiding the issue.  what is it that you find difficult to achieve?  or do you simply enjoy making light of a famous amp sound?

I'm not avoiding the issue, I just don't hear anything about the brown sound my amp and pedal can't achieve as well and indeed, better. I think it's just a matter of good harmonic resonance and the set of harmonics you've amplified in your clipping stages. When you start adding elements of a harmonic that is a fraction of an octave above and below your guitar's frequency output, you get a resonant effect that almost sound like it's from the chamber of your speaker cabinet. I'm going to go out on a limb here and assume BSIAB is just adding some distinct harmonics, maybe even atypical, that sound really good and add a chambering like resonance to the tone. To me, the brown sound seems to be a dark, bassy tone with some gutteral midrange just a step above the bass bands while the treble chimes in from a deep void so it's likely a harmonic adding a large peak in the treble that is otherwise, pretty flat.

My pedal does this really well. With some guitars, I almost get a vague chorus or octave effect...though I'm not crazy about it. I've also modified my amp to produce some very unusual, high order harmonics. From what I hear in the Brown Sound, it's probably the exact same thing. The main difference being I'm running a solid state and can go from Van Halen to numetal or even industrial at the turn of a dial and everything in between.
I suppose if you saw my amp, and I'll never divulge the actual circuits I've added, you would then easily understand how. The sound clip also shows off the great dampening effect I've achieved and unlike your tube, I can control it with a threshold knob rather than relying on the EQ, gain and volume controls. 

[stringsthings]

I'm not avoiding the issue, I just don't hear anything about the brown sound my amp and pedal can't achieve as well and indeed, better. I think it's just a matter of good harmonic resonance and the set of harmonics you've amplified in your clipping stages ....

Fair enough.  and I thank you for your informed response.  I listened to your sound clip and found the sound of your circuit interesting.  IMO, it's very different from Van Halen's sound.  But that's just my opinion. 

[ViolenceOnTheRadio]

I'm not avoiding the issue, I just don't hear anything about the brown sound my amp and pedal can't achieve as well and indeed, better. I think it's just a matter of good harmonic resonance and the set of harmonics you've amplified in your clipping stages ....

Fair enough.  and I thank you for your informed response.  I listened to your sound clip and found the sound of your circuit interesting.  IMO, it's very different from Van Halen's sound.  But that's just my opinion. 

No surprise considering the purpose of the clip was to demonstrate the dampening factor..which now unfortunately the circuit needs revamping since I modified my gain set pot/system. Getting Van Halen tone was the furthest thing from my mind when I recorded it so I'm a bit unsure why you're making the reference. On occasion I dial in that dark, chimey tone Eddie uses but generally I stick to a complete scooped tone or a balanced tone sometimes heavy on the midrange side of things. If I use reverb, it's generally not really audible.

The only time I ever really dial in any audible effects is typically for psychadelic type stuff or a moderate delay for instrumentals. Eddie has a good tone AKA the brown sound but it's not really suiting to my style.