I've been curious about the Accuphase DC-91's SFA/Sample Frequency Accuracy function.
From the brochure:
I almost never get Level III. I use a PC with foobar as source. Level I or Level II for my music library. Got 1 Level III read from toslink out of my tv and watching The Expanse. Yet it never holds Level III as i replayed the episode and only get Level I. I currently use an m2tech hiface evo usb to spidf for it's ST optical, but i borrowed a Mutec MC-3+ and at first connection-the SFA read Level III, then i never saw it again as everything read Level I or Level II as usual.
Would anyone happen to know if by manual override-it means internally?
When i hold down the SFA button and press volume up at the same time, the display will change to 'on' and when i hold the SFA button and press the volume down at the same time, the display reads 'oF'. There is no change in sound and no change in Level I or Level II read. I don't know what is being turned on and off. Logically i first assumed, i turn Level I off, then Level II off and Level III would be ON, but that means i would have to happen upon a rare Level III reading to turn ON while the others OFF assuming oF means off in the first place. With Level I and Level II OFF, my music still displays Level I or Level II.
I don't see any other button options to manually override to Level III clock.
From the brochure:
I almost never get Level III. I use a PC with foobar as source. Level I or Level II for my music library. Got 1 Level III read from toslink out of my tv and watching The Expanse. Yet it never holds Level III as i replayed the episode and only get Level I. I currently use an m2tech hiface evo usb to spidf for it's ST optical, but i borrowed a Mutec MC-3+ and at first connection-the SFA read Level III, then i never saw it again as everything read Level I or Level II as usual.
Would anyone happen to know if by manual override-it means internally?
When i hold down the SFA button and press volume up at the same time, the display will change to 'on' and when i hold the SFA button and press the volume down at the same time, the display reads 'oF'. There is no change in sound and no change in Level I or Level II read. I don't know what is being turned on and off. Logically i first assumed, i turn Level I off, then Level II off and Level III would be ON, but that means i would have to happen upon a rare Level III reading to turn ON while the others OFF assuming oF means off in the first place. With Level I and Level II OFF, my music still displays Level I or Level II.
I don't see any other button options to manually override to Level III clock.
All I can tell you is that level III is meant for varispeed applications. For example, DJs who mix together dance records by tweaking the rotational speed settings of their turntables can do the same with digital sources, that's a varispeed application.
In Level III mode, the Accuphase uses the lousiest oscillator it has available, so why would you want it to switch to level III?
In Level III mode, the Accuphase uses the lousiest oscillator it has available, so why would you want it to switch to level III?
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Thanks for that info. I was under the impression it leveled up, ha. So Level I is actually the most accurate? So i should actually turn off level II tantalate oscillators?
It automatically chooses the best oscillator it can get to lock onto the source. The level I oscillators are the best, the level II oscillators are somewhat worse and the level III oscillator is far worse.
Thanks a lot for clearing it all up. I went ahead and turned Lvl II to off. I'm not a tech guy. I signed up to find someone for hire to modify this DAC, but i'm still just learning about it. I appreciate it.
