Dirac and a Change of Amplifier.

[Liam]

If following measurement the amplifier is changed for a different one, as in my case, does the measurement need to be done again? For example if the frequency response, or level of output at different frequencies across the board might be different with the change of amp, would this affect the readings, or is it only the room or speaker/placement that matters?

[rcohen]

Yes, you should re-measure. You could reuse your target curves, though.

[Boris75]

This thread looks like a golden opportunity to launch a debate as to whether all amplifiers sound the same

[wgscott]

The beauty of re-measuring is you can determine whether the new amplifier differs in this regard from the old one.

[rcohen]

When I said yes, I meant that there may be a difference, not that there will be. There's enough of a chance that it's worth remeasuring.

[wgscott]

I would. The software has no way of "knowing" whether it is correcting the room only (i.e., perfect component and speaker frequency response) or the convolution of every component in the signal chain.

[Kal Rubinson]

The beauty of re-measuring is you can determine whether the new amplifier differs in this regard from the old one.

only if you can position the microphone in each and every run identically. I'd guess that such variation, even with extraordinary care, would swamp any differences among decent amps.

[dallasjustice]

Do you have a 2CH system? If so, you could remeasure but it's unlikely to make a big difference in your result. If you have more than 2CH, you would need to remeasure for sure since the 2 amps don't likely have the same gain.

[beanbag]

Don't bother. Most amps have a flat frequency response in the range that Dirac measures.

[Liam]

Thanks everybody for your advices. The consensus is that I should re measure, and that is what I will do. I reckoned I wouldn't be happy until I did it again unless the consensus was totally in the opposite.

 

I will wait a while as there is only 50 hours on the amp and AMR say upto 300-500 hours for it to settle fully, and I am playing with coupling and/or isolation of the entire system also as things progress.

 

All that said the existing filter seems to be doing its job following the amplifier switch, but who knows there might be some differences, even if subtle, when done again.

 

Like Kal said maybe any such differences might be down to relatively small changes in mic positions between the two measurements. In any event I will post the results when done, which might be of interest.