In a word, yes. The ADI-2 has significantly lower SNR at low to moderate output
Thanks. Well, I was planning on using my ADI-2 to directly control volume of a pair of NC-400 monos. I might just abandon that idea then.
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In a word, yes. The ADI-2 has significantly lower SNR at low to moderate output
That is exactly what I do with my RME. I use a passive preamp that was custom built with excellent attenuators and switches
Thanks. Well, I was planning on using my ADI-2 to directly control volume of a pair of NC-400 monos. I might just abandon that idea then.
You also decrease SNR when using passive volume control.
At full volume Schiit Sys is transparent. As we lower the level on Sys, naturally the measurement noise as a percentage rises leading to the graphs that you see. In other words you lose signal to noise ratio with passive volume controls.
I see no reason not to use the ADI-2 DAC as a preamp, in it's lowest reference level of 1 dBu its balanced output has a residual noise of 1.16 uV which is extremely low, even lower than the Benchmark LA4 (<1.9 uV) which to my knowledge is the best analog preamp there is (or at least one of the very best). While it's theoretically true that a DAC loses SNR as you turn down the volume, it doesn't matter since if the noise isn't audible with the volume turned up it's not gonna be audible with the volume turned way down since the noise is at a constant level.Thanks. Well, I was planning on using my ADI-2 to directly control volume of a pair of NC-400 monos. I might just abandon that idea then.
With auto ref level being off, obviously? Just to be clear..)in it's lowest reference level of 1 dBu its balanced output has a residual noise of 1.16 uV
SNR will drop at lower levels, but how much? Some methods drop more than others. The RME discussion on p. 63 is a bit of a straw man argument, as it pertains only to conventional analog potentiometers. There are other alternatives, such as a stepped attenuator using metal film resistors. Alternatively, one could drive the full scale DAC output into an active analog stage having less than unity gain (instead of a typical analog stage, which has fixed gain at unity or greater with attenuation through adjustable resistance).You also decrease SNR when using passive volume control.
Read page 63:
http://www.archiv.rme-audio.de/download/adi2dac_e.pdf
...
You should always have it on if you want to maximize the SNR at any volume level, if you turn the volume down enough with auto ref level on it will eventually switch to the lowest ref level with the lowest noise.With auto ref level being off, obviously? Just to be clear..)
Nope.Thanks. Well, I was planning on using my ADI-2 to directly control volume of a pair of NC-400 monos. I might just abandon that idea then.
Thanks. One of the reasons that I care about this issue so much is because some mastering engineers started to use a conservative mastering technique which permanently damage the sound quality of distributed music.I found this thread had useful feedback on this topic.
https://www.audiosciencereview.com/...ttenuation-before-power-amp.5844/#post-131431
@bennetng makes the point that it is best if you can do the attenuation in software with 32bit or 64bit floating point calculations.
He goes into much more detail in his guest post on Archimago’s blog.
http://archimago.blogspot.com/2019/06/guest-post-why-we-should-use-software.html
This is all new to me, but I have been furiously reading around this topic for the last few weeks.
Provided that the digital signal is not clipped before or during conversion.eliminate the digital attenuation entirely
Then you rebuild the Benchmark LA4, somehow.Instead of having only 4 steps, why not have 50 or 100 steps
From what I read here, I agree. RME's "Ref Level" feature optimizes its output for whatever level is being used, from full scale to the low to moderate levels we actually use during listening. That's really neat. Some of the best DACs measured here (such as the Matrix Element X) do not do as well at low output levels.... Subjectivly speaking, then: The ADI-2 DAC, as preamp, is a dream to use and listen.
From what I read here, I agree. RME's "Ref Level" feature optimizes its output for whatever level is being used, from full scale to the low to moderate levels we actually use during listening. That's really neat. Some of the best DACs measured here (such as the Matrix Element X) do not do as well at low output levels.
SMSL SU-8I've mentioned this many times for people. Go away for a holiday, come back, sit down to listen to music and your D/A has defaulted to 0dB. Boom! Power cuts can do this also. There's no substitute for a real volume control in my opinion, especially if you have a lot of power on tap and expensive speakers.