DeltaWave fun: measurements and audibility.

[PierreV]

I own a bunch of amps and decided to have a bit of fun...

Test setup:
- umik about one meter away from a KEF LS 50
- levels matched with REW logging 89.4 and 89.6 peak.
- CD quality source on AUX
- one of the amps I subjectively find too bright (reference - solid state, but not "digital" )
- the amp I subjectively find smooth, too smooth for many things, but great for soft jazz at night and female voices . Tube/SS hybrid
- some background noise

both around 10-15 years old, members of my "swap pile" audio stuff.

Will probably do the same type of comparisons with the big systems at some point but moving 85 kg speakers, switching XLRs, preamps, matching levels etc really a lot of work.

There is definitely a correlation between my too bright and too smooth perception and the measurements


Initial peak values File 1: -18.183dB File 2: -19.437dB
Initial RMS values File 1: -37.505dB File 2: -36.219dB

 

[PierreV]

And I tried to resist, but came back to it...

Matched as well as I could.
Initial peak values File 1: -17.85dB File 2: -16.939dB
Initial RMS values File 1: -36.553dB File 2: -36.265dB

All computational compensation disabled in DeltaWave.
Worst measuring stand-alone DAC I have ( CCA line out ) vs best measuring stand-alone one (Khadas Tone Board).
Roon "perfect" path to CCA and VolumeIO driving Khadas, same file from my library.

Can you tell which is which?
I know because it was a sighted test of course. I'd say the difference was audible and I have a preference but it must be biased.

Assuming I did not know, are there specific things I need to look for, giveaways?
Would the umik be OK?
Except for totally different amplifiers or speakers, this is the biggest change I could come up with. Trying to educate myself for the cases I want to check the impact of more minor changes... Blinking the spectrogram shows quite a few interesting things, but hard to post here.

Note: and I don't like that line around 15kHz too much, need to debug things to see where it could come from (there were PCs, lights and SPMS in the room obviously)