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Best way to match ADI-2 DAC gain with KH750/KH80

radix

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I just upgraded my DAC to an ADI-2. Hurray me. Anyway, the XLR line outs drive a KH750/KH80 used very near field on a desk. I find I am listening to it with the volume around -50 dBr with reference level at -5 dBu (+1 dBu balanced). I find a volume of -20 dBr pretty loud (still at -5 dBu).

I use the Neumann room correction software.

Is there a better way to level match these so I'm not so far down in the -gain? I can't say I really hear any noise, so maybe

Would that be the input gain select on the back of the KH750?

Would I need to re-run the Neumann software after adjusting this? I've not re-run the software since switching to the RME and balanced inputs.

Thanks
 

Trell

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-50 dBr is low and you should adjust the sensitivity on the subwoofer and monitors, and in worst case you’ll have to use passive attenuators so that full volume will not blast your ears off.

I don’t own Neumann monitors, but I guess that monitors and subwoofer should have the same input sensitivity setting. Probably you’ll not need to recalibrate and that would surprise me. Of course, check the manuals for details.

I’ve Genelec monitors with DSP and they are also very sensitive by default, but setting monitor volume 25 dB down (same as changing input sensitivity for Genelec SAM monitors) I’ve my RME ADI-2 DAC FS volume at -30 to -20 dBr for normal listening.
 

Χ Ξ Σ

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I was in a similar situation. My setup includes RME Fireface UCX II, Genelec 8341A, and SVS SB4000. At the beginning I set the Genelec -20dB and SVS -35dB. The volume on RME would be -30dB to -10dB. I didn't hear any problem for a long time until one day I switched it up to Genelec -0dB, SVS -15dB, and RME -50dB to -30dB. The latter setting sounded so much better. The previous setting gave more sibilant treble and stiffer bass. I did do in room measurement that confirm the room response stays the same, but the latter setting just sounded so much better in all volume range.

This makes sense to me in theory. The digital volume control in RME is better than those in Genelec and SVS. I would rather attenuate through RME than the other two. I would encourage the OP to try both ways and go with the setting that sounds better.
 

MC_RME

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I just upgraded my DAC to an ADI-2. Hurray me. Anyway, the XLR line outs drive a KH750/KH80 used very near field on a desk. I find I am listening to it with the volume around -50 dBr with reference level at -5 dBu (+1 dBu balanced). I find a volume of -20 dBr pretty loud (still at -5 dBu).

I use the Neumann room correction software.

Is there a better way to level match these so I'm not so far down in the -gain? I can't say I really hear any noise, so maybe

Would that be the input gain select on the back of the KH750?

Would I need to re-run the Neumann software after adjusting this? I've not re-run the software since switching to the RME and balanced inputs.

Thanks
It seems you misunderstood the levels. dBr always relates to the highest possible output level. For the DAC that is +19 dBu at the XLR output. So -50 dBr turns on the +1 dBu (balanced) Ref Level, but the digital volume is then set to 50 minus 18 = -32 dB. You can easily verify this by deactivating AutoRef. -32 dB is fully ok. -20 dBr translates to -2 dB volume setting (fully ok too. Remember: if you have EQ active with some gain increase, AutoRef will automatically use a higher Ref Level to preserve headroom).

Now to theoretically optimize this all you could get yourself XLR attenuators and lower the output level by -10 dB. That would add a few dBs of measurable SNR as the ADI runs at a higher digital volume setting and a higher Ref Level then. I doubt you would be able to hear any difference, though.
 
OP
radix

radix

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It seems you misunderstood the levels. dBr always relates to the highest possible output level. For the DAC that is +19 dBu at the XLR output. So -50 dBr turns on the +1 dBu (balanced) Ref Level, but the digital volume is then set to 50 minus 18 = -32 dB. You can easily verify this by deactivating AutoRef. -32 dB is fully ok. -20 dBr translates to -2 dB volume setting (fully ok too. Remember: if you have EQ active with some gain increase, AutoRef will automatically use a higher Ref Level to preserve headroom).

Now to theoretically optimize this all you could get yourself XLR attenuators and lower the output level by -10 dB. That would add a few dBs of measurable SNR as the ADI runs at a higher digital volume setting and a higher Ref Level then. I doubt you would be able to hear any difference, though.

Thank you for clarifying that. It makes sense now.
 
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