Audio attenuation choices - u1m, dave, pre..?

Question to the group: It seems the analogue level out of the Chord DAVE is saturating the bal inputs to my pre (Classe SSP, old but good); for many albums the DAC setting on the DAVE is ok for the system - which outputs -3dB metered, which the manual says corresponds to 6V at the bal outputs - but on more modern masters, the levels saturate the analogue input stage and I get distortion/clipping. Consequently, I operate the DAVE in Pre mode which has a volume control in line, and in general I have to be around -10dB metered (dBFS?), which I’d interpolate to be about 2.7V or so at the bal outs. That makes the Classe happier, so, fine. I’d rather not, but unless I go straight to the amp and use the DAVE as the pre (which I may) or get another pre (which I may), this is what I have to do for the moment.

So, the question is: should I be doing this level attenuation in the U1 mini instead? Is there a way to set the output level to -10dB, and will this level stick through shutdown and startup, power loss, etc? And with Leehd processing enabled, this is lossless, correct?

Thoughts? @wklie, et al? Thanks!

Please compare the SQ with U1 MINI with Leedh Processing Volume and Volume Control enabled, and set Lumin volume to 80 (i.e. -10dB), while the DAVE volume to 0dB.

Yes, unless the power loss occurs right after the volume adjustment before it gets saved internally.

Which model of Classe SSP are you using?

Some of the above figures do not seem right to me.

Thx much Peter. I will do that tomorrow or so, and see what it sounds like. I assume just fine. Will report.

It is a Classe CT-SSP, which is the same as the SSP-800, with rack mount, etc for custom install.

I have not put a meter on the outputs or fed any test tones, which I can do, but atm I’m just going off what the Chord manual says (which is not a lot, :slight_smile: ).


If I read the specs right, the CT-SSP has input sensitivity of 4V rms.

With Chord DAVE spec of 6V rms at -3dB (or 6.2V measured by stereophile), you should only need an additional -4dB (i.e. -7dB) to lower the output to below 4V in order to prevent it from clipping.

With DAVE set to 0dB, you can achieve -7dB from Lumin by setting Lumin volume to 86.

Right. 4Vrms is the spec for bal, I had assumed the outputs on the DAVE would conform to that, but everybody is just cranking the levels these days.

Yes, I had done a little mental math, too, and ended up setting Lumin to 85 and set the DAVE in DAC mode, which should be about -10 net. The two tracks I just played did fine, so if it sticks I’ll prob bump Lumin up to 90 (-8 net or thereabouts…? taking the fixed -3 of the DAVE in DAC mode).

But it does sound good, Peter, just FYI. Nice volume algorithm. Me like.

Thanks a lot for the help.

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Please keep the DAVE in preamp mode at 0dB, not DAC mode -3dB, if you use Lumin volume control.

I have 3 Lumin’s D1/D2 and the volume settings is very stable and remains as set by the Lumin App for anything I throw at them. Solid product and support is stellar too.


Oh really? The only reason that is frustrating (as I would normally like to 0 it too) is that that means the volume knob is active on the DAVE and susceptible to little hands turning it up - not kids but friends and significant others :smiley: - the DAVE has about +19dB gain and that would fry some stuff. So, I thought to leave it in DAC which fixes the level at -3.

BUT, I will do as you say, cause I agree and would like to have it clean and clear. Just have to put some caution tape around the knob :smiley: .

Do you need any DSP features from the CT-SSP? Otherwise you should use its bypass mode. With bypass mode the sensitivity is much higher and it shouldn’t even clip without any digital volume adjustment from DAVE or Lumin.

It is in bypass mode, yes. Absolutely. The only mode I configured for the two-channel system. *

The 6-ch video system uses DSP for Dolby/DTS proc, etc. But not the music system. Totally separate signal path.

Thanks Peter!

*Edit: This is mode that clips, though. So it may have higher p-p tolerance than the 4V spec, but it’s not by much it seems.