If I read this correctly, it's an IMD measurement, but the calculation method has lower noise immunity than other methods, so it gives a lower result when signal level is low.One question: the unit that AP call "SMPTE ratio (dB)", is it synonymous to "IMD" in Multitone and "IMD DIN" in REW, or is it synonymous to TD+N?
Cosmos ADC IMD hump isn't really hump but you can find some nonlinear area on the plot.
No )) You did find APx555 noise limitation, as usual, I believe. That's why AP's products IMO 10x-5x times overpriced. You can pay $30000 or as L7 in China even $50000 and you still can not measure $13 DAC's DR with the <10x error. Isn't it ridiculous?I'm looking into it right now.
One question: the unit that AP call "SMPTE ratio (dB)", is it synonymous to "IMD" in Multitone and "IMD DIN" in REW, or is it synonymous to TD+N?
If it's the former, then how come my $100 SG3 beats the D90SE by 20dB at -60dBFS Generator level?
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Is this using the AM demodulation (ie. SMPTE IMD) which includes noise within the passband, or harmonic picking (ie. MOD IMD) which rejects noise except in the frequency bins of the relevant harmonics? If the former, do you see similar results with the latter?No )) You did find APx555 noise limitation, as usual, I believe.
Here is their specs page: https://www.hidizs.net/pages/hidizs-s9-pro-balanced-single-ended-mini-hifi-dac-amp-specifications Better, check the independent measurements at the top of this thread.At what power?
I always look at the 5mW region, that will tell me how good this DAC really is.
Especially for 32 ohm iem.
I wouldn't know what to look for but thanks for clarifying his request. I'd say it's still all Latin to me ... except I still remember a lot of Latin. greek I guess. But I'm boning up and maybe I'll get there. Thanks for your patience.The measurements at the top of this thread do not included performance under load, which is what jasonhankjk is interested in.
That's not a notch. It's the effect of dominant H2 falling outside the measurement bandwidth. It's clearly at entirely unconcerning levels either way.
Intermodulation distortion (swept tones)
Left Right IMD + Noise at 5000 Hz, 0.00056 0.00066 IMD + Noise at 10000 Hz, 0.00041 0.00050 IMD + Noise at 15000 Hz, 0.00037 0.00051
These are under load, but only one "snapshot" per load and output jack, so pretty low res:Were the third-party measurements we looked at a while back under load?