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previous: anonymous ok.. so negative current feedback i... -- 11/8/1999 4:43 PM

Re: Advanced feedback loop questions..

11/8/1999 7:05 PM
Don Symes	Re: Advanced feedback loop questions.. It _is_ a reversal of polarity to switch from (+) FB to (-). The result, though, will be that as the output moves off center (for any reason whatsoever), the (+)FB will urge it to move ever further in that direction until it saturates against one rail or the other with very little hope of getting it back off the rail except a full-amplitude pulse of the opposite polarity, which will merely slam you against the other rail. I remain mystified about your reasons for wanting to turn your guitar amp into a square-wave generator (best case) or a smoking slag heap (worst case), but hey... Proceed, if you must, with EXTREME caution.

11/8/1999 7:05 PM

Don Symes

Re: Advanced feedback loop questions..

It _is_ a reversal of polarity to switch from (+) FB to (-). The result, though, will be that as the output moves off center (for any reason whatsoever), the (+)FB will urge it to move ever further in that direction until it saturates against one rail or the other with very little hope of getting it back off the rail except a full-amplitude pulse of the opposite polarity, which will merely slam you against the other rail.

I remain mystified about your reasons for wanting to turn your guitar amp into a square-wave generator (best case) or a smoking slag heap (worst case), but hey...

Proceed, if you must, with EXTREME caution.

Replies:

David Manson Positive feedback is always bad? i ... -- 11/8/1999 7:40 PM