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previous: Troy I was just wondering if there is a ... -- 9/22/2004 3:49 PM

Re: Low End

10/3/2004 5:45 PM
Brutus	Re: Low End Flubby low end is often because there simply is too much bass when the amp plays distorted. Tighten up distorted low end by simply backing off on the bass. Tight clean low end is a different story. For that you need good speaker damping and low low impedance coupling between stages. To increase damping you can 1) Increase the impedance of the output tranny. 2) Increase the use of negative feedback throughout the amp. 3) Liberally use cathode followers to drive stages, especially the tone stack stage. 4) Consider driving the final output stage with cathode followers especially when the final stage consists of four or more tubes in PP or two or more tubes in SE. There has been a big push over the last 5 years for amps with no negative feedback. In some circles, it is considered heresy to even mention the use of negative feeback. That is all well and good but the absence of negative feedback will make the amp's bass a little more flubby. Also, certain speakers are better at damping than others. I think the celestion G12H30 does a pretty good job of it as well as the Celestion alnico blues. Finally, some guitar pickups are flubbier than others. Humbuckers sometimes have problems delivering tight bass. Try single coils instead. If you absolutely have to have humbuckers (OK, you play a LP) then use P-90's instead. Can't say enough good things about P-90's for good bass response in guitars. Brutus

10/3/2004 5:45 PM

Brutus

Re: Low End

Flubby low end is often because there simply is too much bass when the amp plays distorted. Tighten up distorted low end by simply backing off on the bass.

Tight clean low end is a different story. For that you need good speaker damping and low low impedance coupling between stages. To increase damping you can

1) Increase the impedance of the output tranny.
2) Increase the use of negative feedback throughout the amp.
3) Liberally use cathode followers to drive stages, especially the tone stack stage.
4) Consider driving the final output stage with cathode followers especially when the final stage consists of four or more tubes in PP or two or more tubes in SE.

There has been a big push over the last 5 years for amps with no negative feedback. In some circles, it is considered heresy to even mention the use of negative feeback. That is all well and good but the absence of negative feedback will make the amp's bass a little more flubby.

Also, certain speakers are better at damping than others. I think the celestion G12H30 does a pretty good job of it as well as the Celestion alnico blues.

Finally, some guitar pickups are flubbier than others. Humbuckers sometimes have problems delivering tight bass. Try single coils instead. If you absolutely have to have humbuckers (OK, you play a LP) then use P-90's instead. Can't say enough good things about P-90's for good bass response in guitars.

Brutus