18-Mar-2020, 00:45 (This post was last modified: 18-Mar-2020, 00:48 by Superdad.)
(17-Mar-2020, 22:50)thumb5 Wrote: It seems from these twoposts on ASR that Alex was mistakenly referring to specification for the digital inputs of the AP test equipment, which aren't relevant to the measurement that ASR carried out based on the analog output of the DAC fed by the ER, and that the test gear is more than capable of measuring the levels of jitter UpTone refer to at the DAC clock (whether or not that is the right thing to be measuring).
Remember though: The analog inputs of the Audio Precision go through whatever A/D converter is built into it. It is a 24-bit ADC (plus filters), but jitter specifications for it apparently are not given anywhere. I suspect (but can not confirm) that the jitter specs for their A/D converter are the same as for their digital inputs--could even be worse. Plus, Amir is not zooming into the skirts of the jitter spectrum spike, so you really can not see what is occurring at close-in offsets.
18-Mar-2020, 07:59 (This post was last modified: 18-Mar-2020, 08:08 by thumb5.)
Alex, it was pointed out that the FFT displayed by the AP test gear necessarily includes any jitter associated with the conversion process, which would also appear as sidebands if present. The FFT output is shown to be clean, for a well-performing DAC, down to about -150 dB. If you don't mind me saying, speculating about the internal behaviour of the AP test gear does you no favours.
ETA: I trust that you didn't overlook my questions in post #513 and will answer them shortly.
Roon (Mac Mini), Wilson Benesch Full Circle, Expert 1000 Pro CI, Kaiser Chiara
18-Mar-2020, 13:18 (This post was last modified: 18-Mar-2020, 13:18 by K4680.)
Hi folks, at the university (measurement technology) we had a cool professor with the following saying:
If you measure a lot, you measure a lot of crap. Especially if you can't or don't want to interpret it!
Hi, after about 4 weeks of experience with my Melco S100 switch, I can't find anything negative. In terms of sound, the last 2 weeks have changed to a positive one! The only negative is the distance between the LAN sockets, with some cables it gets tight! This is better solved with other manufacturers.
Did you make use of the fiber optic connection too?
Thanks.
Hi, in the beginning the sound was a bit rough and hard, that has totally changed. Now the sound is pleasant and not annoying and harsh. I do not use fiber!
NETWORK SWITCH FROM RUSS ANDREWS
Russ Andrews Accessories is launching a dedicated audiophile grade Network Switch. At its heart is a custom Trichord Clock, which is used to coordinate the timing of the digital signal.
Wow! Thanks for this update. I would be very curious to have a look at the innards of those 2 boxes to understand justification of GBP £ 989.
Roon Nucleus w/ Hypsos PSU & AQ Tornado + Roon RAAT > AQ Diamond ETH > etherREGEN using SFP + Hypsos PSU | CEC TL-5 CD Transport + AQ Z3 + 3 x Orea Indigo > AQ Diamond AES/EBU
Devialet 440-Pro CI > AQ Wel Sig RCA-XLR | 6 x Orea Bronze, 2 x Synergistic Research Atmosphere PC | B&W 802 D3 {Bi-wired} > AQ WEL Signature (Biwire)
REL G1-Mk2 pair | PS Audio PP 12 + AQ NRG-1000 | Puritan GroundMaster + RouteMaster | SAM DISABLED - DPM OFF - Northern Virginia - US
(29-Mar-2020, 17:42)audio_engr Wrote: Wow! Thanks for this update. I would be very curious to have a look at the innards of those 2 boxes to understand justification of GBP £ 989.
I very much doubt you'd see that from looking at the insides. I strongly suspect that in this case (pun intended) it's more a matter of what the market will bear.
Mind you, if they've put a generic PSU in a separate box, which seems likely, that's an instant price hike simply because cases and connectors are notoriously expensive compared to electronics.
Roon (Mac Mini), Wilson Benesch Full Circle, Expert 1000 Pro CI, Kaiser Chiara
