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Old 03-19-2017, 09:50 AM
Cuki79 Cuki79 is offline
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Quote:
Originally Posted by guitaniac View Post
In my own case, I always felt that the digitally enhanced (by Aura or Mama Bear) pickup signals were a bit more feedback prone than the dry signals.
Funny you mention that. Yesterday I tried to implement the extra filter stage from the Tonedexter patent (presumely the secret button).

When you compute a "minimum phase" filter , meaning that all the frequency information interfere constructively in time domain at te begining of the impulse and you use it as a raw IR (just for test since it is meant to be blend in the patent).... Man! I got huge feedback.

Dont draw any conclusion on the Tonedexter:
1) I am using a Lyric microphone which is not the 1st target of Tonedexer.
2) I am testing a "part of the algorythm" for test and I am not even using as intended.

My conclusion so far, it that you get a better "directness/immediacy" in sound but are more feedback prone. I am pretty sure they don't blend the "minimum phase" filter as is... Or I got something wrong, but It's a good lesson.

There is a way to manage feedback through phase frequency discrimination. I think it can't be bad. I mean before we only had notch filter and whole phase signal reversal. It would be interesting to explore phase modulation specific to the low frequency resonance of guitar.

Previously I've shown my own IR to a cousin in total different condition (JAM 150 amp on a hard floor) and It was much more prone to feedback at his place. I believe for Lyric users. Digital IR needs to have a specific strategy, especially as far as the phase is concerned. However since the low-end is "created" from scratch, it can probably tuned to avoid feedback.

I still think there is hope. I did not spend any time digging in that direction...
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