quick gain question

[nognow]

is it possible to increase the gain of a TS9 by changing the "drive" pot from a 500k to 1M?
Thanks!

[PBE6]

Yes. But you won't notice much of a difference in the saturation of the distortion (although the high end will be rolled off in the gain stage starting at 3.2kHz instead of it 6.2kHz, making it sound less bright).

If you want to know whether increasing the gain pot value will make it sound more like a distortion pedal than an overdrive, unfortunately the answer is no. The non-inverting gain stage in the Tubescreamer always mixes in the original signal so you'll never get that wall-of-fuzz sound from it.

[Elijah-Baley]

I replaced the 500k with a 1M pot, in a veroboard layout project of the TS808.
And I changed the 4,7k resistor with a 2,4k, like the keeley mod. I got a little bit more aggressive sound.

[nognow]

Yes. But you won't notice much of a difference in the saturation of the distortion (although the high end will be rolled off in the gain stage starting at 3.2kHz instead of it 6.2kHz, making it sound less bright).

If you want to know whether increasing the gain pot value will make it sound more like a distortion pedal than an overdrive, unfortunately the answer is no. The non-inverting gain stage in the Tubescreamer always mixes in the original signal so you'll never get that wall-of-fuzz sound from it.

isn't "saturation" the same thing as "distortion"?

[slacker]

Yeah they're the same thing. What he means is the TS sounds like you are mixing some clean with the distortion, the peaks of the signal sound a bit clean and as the sound decays it sounds distorted. Adding more gain won't get rid of this effect but it will add more sustain to the notes.

[nognow]

I replaced the 500k with a 1M pot, in a veroboard layout project of the TS808.
And I changed the 4,7k resistor with a 2,4k, like the keeley mod. I got a little bit more aggressive sound.

Yes. But you won't notice much of a difference in the saturation of the distortion (although the high end will be rolled off in the gain stage starting at 3.2kHz instead of it 6.2kHz, making it sound less bright).

If you want to know whether increasing the gain pot value will make it sound more like a distortion pedal than an overdrive, unfortunately the answer is no. The non-inverting gain stage in the Tubescreamer always mixes in the original signal so you'll never get that wall-of-fuzz sound from it.

Yes. But you won't notice much of a difference in the saturation of the distortion (although the high end will be rolled off in the gain stage starting at 3.2kHz instead of it 6.2kHz, making it sound less bright).

If you want to know whether increasing the gain pot value will make it sound more like a distortion pedal than an overdrive, unfortunately the answer is no. The non-inverting gain stage in the Tubescreamer always mixes in the original signal so you'll never get that wall-of-fuzz sound from it.

Got it,Thanks!

[PBE6]

What I mean is that you won't notice a big change in the quality of the distortion. With the 1M pot maxed out it will sound less bright and slightly grittier, and it will sound like a Tubescreamer. If that's what you're looking for, this would be an excellent mod.

Lately I've been thinking about distortion as a mix of clean signal and hash. The more hash, the more saturated the signal. Tubescreamers are a mixture of the original signal plus some hash, diode-to-ground distortions like the DS-1 or Distortion + have less original signal and more hash, so they sound more saturated. If you put a blocking resistor between the diodes and ground on a Distortion +, it ends up mixing some of the original signal back in so it's less saturated even though the amount of hash (i..e. distortion) hasn't changed.

[ashcat_lt]

It's less than 6db difference in gain.  

Most of that will come across as extra volume on the output, and possibly more distortion from anything down the line.  The nature of this particular beast, though, is that after a certain point it actually gets cleaner as you add more gain because it gets above the diode drop faster, and spends more of the swing near unity gain.  The diode action starts to become more a type of crossover distortion.

[PBE6]

Although the calculated gain may increase by about 6 dB when going from a 500k pot to a 1M pot, the actual volume increase is virtually non-existent. According to the simulation, the calculated difference in RMS values for the two cases is less than 0.002 dB. I also threw together a Tubescreamer gain stage with a 1M linear pot and recorded myself playing to see if anything was audible. There is definitely a bit more noise and some darkening of the sound at the 1M setting, but the audio levels were within 1 dB of each other during heavy strumming. Overall they sounded very similar. By the time you get to 500k gain settings even the smallest sounds are causing the diodes to conduct heavily, there isn't much room to grow even with a 1M setting.

It also continues to be dirty at extremely high gain settings as the amount of diode distortion never decreases. The waveform does begin to look very well behaved, but it continues to be a mix of the original signal and (slowly but constantly increasing) distortion. The distortion just begins to flatten out slightly at the edges which makes it look like the original signal just moved up by 1 diode drop.