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by earthnail 1165 days ago
The Kemper amp is mathematically super elegant. Two matrices A and B, and one nonlinearity in between. That’s it. All the noise profiling does is figure out A and B, which correspond to the impulse response before and after the distortion.

When you send through a clean signal, you measure A*B. When you get distortions, you know you’re only measuring B (because they are introduced after A). Then you derive A from that.
2 comments
klipklop 1165 days ago
Yeah the newer approach NAM used is much more accurate. Especially for high gain stuff. There are still some aliasing problems with NAM though. Even with that most would never hear about the difference of the real $3500 amp and the free NAM plug-in.

Playing feel on the other hand I guess is a different argument. Not sure if that is a placebo though. I do prefer the zero latency of all analog gear.

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gizajob 1165 days ago
I always think part of the ongoing use of valve amps is because of their transient response. It would be impossible to check in practice, but I think the transient latency is lower than solid state, because they're amplifying in a free field inside the tubes. I'm not sure how digital physical modelling and class-D power amplifiers is ever going to fully replicate this. The Kemper is naturally more convenient and feature-packed, but a valve amplifier will always do the one job that really counts, basically perfectly (until it breaks or catches fire).
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ofalkaed 1164 days ago
90% of the reason tube amps live on is because all the cool kids use them because the cool kids are in bands and tube amps are easy to fix. A dozen tube types and a good supply of resistors and capacitors is all that is needed to fix most tube amps which means you can get your amp fixed asap at any repair shop, common parts they all have in stock. With solid state there is a very high probability that parts will need to be ordered since no one can keep the very large number of possible parts those amps use in stock so you end up buying a new amp to finish the tour with and ship the old one home or abandon/sell it.
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jononor 1165 days ago
That is very interesting. So you have any resources to learn more about this approach to modelling?
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