Suggestions or ideas for tightness control?

[VaporDemon]

I’m looking to add a global tightness control circuit to my amp. My initial idea was a 3 way tightness switch to change the coupling cap value after the first gain stage and instead I was thinking of implementing a low cut pot after the first stage coupling cap. I figure a .047 for the coupling cap and then a pot with something between 250pf to 1000pf depending on what my results are. Any thoughts or suggestions on any of this?

 

[Purgasound]

A schematic would help determine a good course of action rather than choosing arbitrary values.
The flub comes from excess bass, as you are aware. You can trim this either through a coupling cap or cathode bypass cap or a combination of both. Picking the value of either really depends on how the circuit is tuned. A lot of these awful modern high gain amps use 1n coupling caps which are ridiculously small and partly why a lot of this modern high gain stuff sounds thin and anemic when compared to something like a 2203. Even a boosted 2203 has the same issue with low end as the boost will either help cut some off or you can reduce the preamp volume control to allow a bright cap to pass signal. Those act like a variable high pass filter for the most part until the divider formed by the control gets too low. I tend to use a larger bright cap, somewhere around 4700pF or I'll even hardwire one into a gain stage that won't have a variable control in high gain circuits.
All in all, yes, you can absolutely wire in a 3 way coupling cap selector. Without seeing the circuit I don't know which values to select because you can implement this following the first, second or third stage. I like to limit bass very little early in the circuit and do the larger trimming later since you don't necessarily want to lose all the harmonics generated by distortion through the full spectrum. I would say this is mainly why certain high gain amps sound thin as they chop it all off right after the first stage. A 3-way selector to go from 2.2n, 6.8n, and 10n would be a good mix in a high gain circuit or 6.8n, 10n, and 22n. Experiment with placement in the circuit.

 

[glpg80]

A schematic would help determine a good course of action rather than choosing arbitrary values.
The flub comes from excess bass, as you are aware. You can trim this either through a coupling cap or cathode bypass cap or a combination of both. Picking the value of either really depends on how the circuit is tuned. A lot of these awful modern high gain amps use 1n coupling caps which are ridiculously small and partly why a lot of this modern high gain stuff sounds thin and anemic when compared to something like a 2203. Even a boosted 2203 has the same issue with low end as the boost will either help cut some off or you can reduce the preamp volume control to allow a bright cap to pass signal. Those act like a variable high pass filter for the most part until the divider formed by the control gets too low. I tend to use a larger bright cap, somewhere around 4700pF or I'll even hardwire one into a gain stage that won't have a variable control in high gain circuits.
All in all, yes, you can absolutely wire in a 3 way coupling cap selector. Without seeing the circuit I don't know which values to select because you can implement this following the first, second or third stage. I like to limit bass very little early in the circuit and do the larger trimming later since you don't necessarily want to lose all the harmonics generated by distortion through the full spectrum. I would say this is mainly why certain high gain amps sound thin as they chop it all off right after the first stage. A 3-way selector to go from 2.2n, 6.8n, and 10n would be a good mix in a high gain circuit or 6.8n, 10n, and 22n. Experiment with placement in the circuit.

This is all 100% correct and I do the same thing with low end control. For big bass you can’t be scared of big caps.

 

[VaporDemon]

A schematic would help determine a good course of action rather than choosing arbitrary values.
The flub comes from excess bass, as you are aware. You can trim this either through a coupling cap or cathode bypass cap or a combination of both. Picking the value of either really depends on how the circuit is tuned. A lot of these awful modern high gain amps use 1n coupling caps which are ridiculously small and partly why a lot of this modern high gain stuff sounds thin and anemic when compared to something like a 2203. Even a boosted 2203 has the same issue with low end as the boost will either help cut some off or you can reduce the preamp volume control to allow a bright cap to pass signal. Those act like a variable high pass filter for the most part until the divider formed by the control gets too low. I tend to use a larger bright cap, somewhere around 4700pF or I'll even hardwire one into a gain stage that won't have a variable control in high gain circuits.
All in all, yes, you can absolutely wire in a 3 way coupling cap selector. Without seeing the circuit I don't know which values to select because you can implement this following the first, second or third stage. I like to limit bass very little early in the circuit and do the larger trimming later since you don't necessarily want to lose all the harmonics generated bynd quite distortion through the full spectrum. I would say this is mainly why certain high gain amps sound thin as they chop it all off right after the first stage. A 3-way selector to go from 2.2n, 6.8n, and 10n would be a good mix in a high gain circuit or 6.8n, 10n, and 22n. Experiment with placement in the circuit.

The circuit started out as an exact copy of the SLO circuit and I have been tweaking it little by little to get it where it works for the way I play and what I am going for. I love all types of amp tones and really dig everything from early classic rock to the most brutal modern metal tones I guess if modern metal isn't your thing I can see why some of the amps wouldn't sit well with certain people and compared to say a superlead or 2203/2204 it's probably sterile and thin. I do like the SLO as is for leads and low to mid gain stuff but when I need modern high gain rhythm tones I usually need to do the Tube screamer thing with the volume up, gain off and tone knob to taste. I am hoping to have it do that without the tube screamer but still have the capability to do the fatter stuff as well. I have actually gotten the circuit pretty close to what I'm looking for but I found it strange how far from the SLO it has become. The 39K cold clipper on V2 had to go, the cathode bypass cap on V1 and V2 had to shrink, and the coupling caps for V1 and V2 had to shrink. Generally I am probably going to keep experimenting with values until it sounds and feels great. Thanks for the suggestions. I will try the larger values out as well. My issue is when going for higher gain tones the lower strings can sound a bit like a fuzz pedal where the notes aren't percussive and punchy anymore. The best way I can describe it is the single notes splatter and buzz almost like fret buzz but its not the guitar its the amp. Anyway thanks for the time and info.