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previous: Margaret Wilson Hi Mike,I play a US... -- 5/30/2000 9:39 PM

Re: Bass "Flubbing Out" in SFPR!

5/30/2000 11:30 PM
MBSetzer	Re: Bass "Flubbing Out" in SFPR! Yup Margaret, I think you are doing the right thing to leave the amp unchanged until you have built confidence on other instruments besides known classics like the PR. If your Tele has a regular bridge pickup, that probably works outstanding like the amp is now, especially with the good speakers you put in. There is a subtle difference in the way the bass can be rolled off by the coupling & bypass caps compared to just turning the knob down, keep this in mind as you study since you have already identified this as an area of concern. The tone stack is set up to have the bass knob roll off tones below an easily audible/reproducible frequency (I don't actually know the design center offhand), with mainly the amount of rolloff adjusted by the knob setting. This is way above the frequency I want to deal with using the fixed EQ of the other stages. I like to gradually decrease the coupling & bypass caps to first attenuate those subsonic frequencies below normal human hearing, then continue judiciously to include those higher bass Hz that fall between that point and where the speaker begins to audibly reproduce low frequency signal. Then again, I don't do this for an amp intended for bass guitar, and even a seven string guitar requires different consideration than a regular six-string. Every guitar/amp/speaker combination is unique, with care the right compromises can be reached so that the stock tone stack still works at the original frequencies, but you can increase the knob further than expected to boost the bass noticably more than before with less flubbiness. The real final test is if you can get a nearly stock tone from a vintage fender guitar with typical amp knob settings (for exact stock sound you may have to turn up the bass a notch or two), and much better than stock sound from a neck humbucker with the same knob settings. That's my opinion anyway . . . Keep at it, if you try hard enough to bring this understanding within reach, you will grasp easiest those things that are closest to you Mike

5/30/2000 11:30 PM

MBSetzer

Re: Bass "Flubbing Out" in SFPR!

Yup Margaret, I think you are doing the right thing to leave the amp unchanged until you have built confidence on other instruments besides known classics like the PR. If your Tele has a regular bridge pickup, that probably works outstanding like the amp is now, especially with the good speakers you put in.

There is a subtle difference in the way the bass can be rolled off by the coupling & bypass caps compared to just turning the knob down, keep this in mind as you study since you have already identified this as an area of concern.

The tone stack is set up to have the bass knob roll off tones below an easily audible/reproducible frequency (I don't actually know the design center offhand), with mainly the amount of rolloff adjusted by the knob setting. This is way above the frequency I want to deal with using the fixed EQ of the other stages.

I like to gradually decrease the coupling & bypass caps to first attenuate those subsonic frequencies below normal human hearing, then continue judiciously to include those higher bass Hz that fall between that point and where the speaker begins to audibly reproduce low frequency signal. Then again, I don't do this for an amp intended for bass guitar, and even a seven string guitar requires different consideration than a regular six-string.

Every guitar/amp/speaker combination is unique, with care the right compromises can be reached so that the stock tone stack still works at the original frequencies, but you can increase the knob further than expected to boost the bass noticably more than before with less flubbiness.

The real final test is if you can get a nearly stock tone from a vintage fender guitar with typical amp knob settings (for exact stock sound you may have to turn up the bass a notch or two), and much better than stock sound from a neck humbucker with the same knob settings.

That's my opinion anyway . . .

Keep at it, if you try hard enough to bring this understanding within reach, you will grasp easiest those things that are closest to you :-)

Mike