Presumably straight loopback?Here's my result for ADI-2 Pro:
View attachment 22416
Presumably straight loopback?Here's my result for ADI-2 Pro:
View attachment 22416
Presumably straight loopback?
Ah, sorry, I actually meant HpW-Works, I always confuse the two. I would use REW, it's getting better and better with each release. Its name, Room Eq Wizard, doesn't do justice to the vast functionality it offers today, it is a full measurement suite with better features than some $$$ software
Hi Matt,
Thanks a lot for the detail explanation! Really appreciate it!
When I have time I will re-test with the suggested values.
Hi Matt, thanks for your input. I did own a 401 however moved it on due to the rising noise floor (with increasing signal level) issue. Thing is (apart from your valid points regarding calibration) I can use a "professional" audio interface, achieve similar results but without the rising noise floor. What do you think the issue is here with the 401 and can it be fixed?
It was a very simple question as to the measurement set up. There was no info about in your post.What loopback? There's no loopback, computer playing test signal to the ADI-2 Pro AE and plot saved from audio analyzer. Balanced connection to the analyzer. IIRC, ADI-2 reference level set to +13 dBu.
i. e. was it the ADI generating signal then looped back into its A to D for measurement.
So, now we know that wasn't the case, what was the audio analyser being used?
Not interested in the out of band stuff and no it wasn't obvious.No, it wouldn't look like that. Because ADI-2's ADC modulator noise slope begins to rise up from 60 kHz onwards (quite typical ADC chip, the noise floor with PCM looks just like DSD128 converted to PCM).
OK, I thought it is apparent from the plot because it has the analyzer's logo. It is my Prism dScope III...
By the way, from the plot you can see the image leakage from the on-chip digital filter around 44.1k and 88.2k.
Running the DAC at 768k PCM or DSD256 with better external filters (and modulator) of course gets rid of those.
It is but there issue of a considerable price difference.I think adi2 pro itself is a better analyzer than qa401. Why not just loop test?
What does the ADI loopback look like for the in band as it appears on paper that the ADI will out perform the Prism.
Why are you concerned about spuria at 105dB down at 40 + kHz?
Aahh so it's inadequate to look at the inaudible stuff as I said I'm not interested in the inaudible.
Agree with the overall advantages of the Prism as a measurement system over the ADI but it is still interesting to see how they compare.
Non perfect doesn't matter if you can't hear it.
Why are you not concerned about say harmonic distortion in the audible band at - 120dB?
Thanks SIY, this is the reason I am very interested in the ADI. The advantages of the very expensive dedicated measurement systems start to greatly deminish when you make a combo as you suggest.All of the measurement issues with the ADI (or other good ADC/DACs) can be dealt with using a front-end signal conditioner like Pete Millett's soundcard interface or Jan Didden's Autoranger. The combo of the Autoranger with the ADI would be tough to beat at any kind of comparable price.
Thanks SIY, this is the reason I am very interested in the ADI. The advantages of the very expensive dedicated measurement systems start to greatly deminish when you make a combo as you suggest.
Why are you not concerned about say harmonic distortion in the audible band at - 120dB?