I am currently using my Chord DAVE with the Blu Mk II in Preamp mode. I am connecting it via both RCA and XLR to two different headphone amplifiers. Can you take a look at the attached pic and confirm the current volume on my DAVE is accurate where it is sending out 2V via RCA and 4V via XLR?
I understand that the industry standard for RCA is 2V while for XLR it is 4V.
I was not sure whether I should be setting it as -2 or +2 on the DAVE.
Should I be changing the volume depending on whether I am using RCA or XLR? or is this current volume setting already the correct one for both RCA and XLR?
I have culled this from somewhere a long time ago, maybe it will help? Also MScaler changes things by -3db.
Dave voltage output.
So I have the following conjecture about why most of the time, RCA is technically superior to XLR from DAVE.
If you’re driving your amp directly, let’s say listening at a volume level of -19dB via XLR so you’re putting 1V via XLR into your amp. If you’re using RCA, your volume level would be -13dB to get 1V into your amp. But since the -19dB signal and the -13dB signal all come from the pulse array DAC which has a fixed noise floor, you’re actually going to get slightly better SNR from the -13dB compared to the -19dB signal. Because the way the XLR generates the 1V signal is to take a -19dB 0.5V signal from the pulse array DAC and then feed it through the inverting amplifier to give you the 1V. So with XLR, you’re starting off with a lower signal with slightly lower SNR and then adding an inverting amplifier which may affect transparency.
Of course, this is purely from the DAC end. Depending on the amp, the signal from DAVE could be attenuated, altered, via RCA/XLR which could also affect SNR or transparency.
To me, the interesting question is for people who normally hook up their integrated amp (or headphone amp with volume control) to DAVE. Because if you normally just set DAVE into DAC mode (-3dB), then RCA would output 3V and XLR would output 6V and you might just adjust the integrated/headphone amp volume control to balance the higher voltage from the XLR and you might prefer the XLR sound. But to me, then, the better comparison would be to use RCA and set DAVE at +3dB so that you’re getting 6V RCA into your amp and compare that to -3dB at 6V XLR into your amp. We are of course assuming that your amp’s volume control is not going to clip a 6V RCA signal. I suspect in that comparison, given the right circumstances, the RCA output of DAVE would likely sound better than XLR.
Bottomline is that there are a lot of factors that come into play once DAVE is feeding an amp or preamp via RCA vs XLR. Which is probably why ultimately, people just need to test this with their amps if they have the luxury to do so.
