Output level


#1

I noticed that the output level of the DAC is 3.15 Vrms rather than the usual 2.00 Vrms. That’s a bit “hot” for my integrated amp and I’m not getting as much range on the volume knob as I would like.

Can I set the digital volume of the DAC to lower than 100? What should it be set at to have an equivalent of 2.00 Vrms output? Will it degrade the sound quality?


#2

I don’t know what volume corresponds to 2 volt output, but you can lower the volume to compensate for a high output. I believe PS Audio recommends keeping the volume at or above 70. When you lower the volume you are cutting out some of the data, somewhere around 70 is where most people will start to notice the loss of data. The PWD is known to have a high output, but the only solution is to upgrade to the DS! The DS has a lower output plus it has a built in attenuator to lower the signal 20 dB further.


#3

This is actually much as I have suggested trying: reduce the level from the PWD and increase the level og the volume control on yout preamp. At some point you are likely to find a sweet spot where the analog volume control and digital level control of the DAC are doing the least total amount of damage to the signal.

I believe that the recommendation for the PWD is to keep the level above 60, which is a 20dB reduction and about 3.6bits reduction in digital resolution. Since it is rare to approach, much less exceed 20 bits of resolution innthe recording chain, there should be no appreciable loss for 24 bit tracks. If you are playing 16 bit tracks, you could fo down another 24dB with no bit loss. That would be (I think) 31 on the PWD volume control scale. I think that 40 is the recommended minimum for no quality loss. I forget the exact inflection points in the PWD volume scale. At the top end of the scale each step is 0.5dB, somewhere in the middle it is 1dB per step and at the low end of the scale it is 2dB per step. Some research will be needed to find these turnover points - this has been posted in the forum some time in the past, several years ago.

J.P.


#4

I did a little searching and found the following from Paul back in October 2013:

“Agreed – but also don’t be afraid to set it anywhere between 50 and 100 that leaves your preamp at a comfortable higher level. It’s instructive to remember most preamps prefer to be 70 and above for best sound on music played at the right level. Volume controls are like the brakes of a car, not the gas pedal – the less you use them, the better she runs (sounds).”

In my defense I would like to say I got the 70 right but the device wrong, alas, that wouldn’t be correct. In reality I couldn’t recall the actual number so I was being conservative (!).


#5

Thanks for the suggestions! I tried 70% on the preamp volume, but at normal listening levels I had to turn down the PWD’s volume to 40.

I’m just going to leave the PWD volume at 80, and preamp volume around 8-9 o’clock position.


#6

It seems that I am also having trouble with my PWD output being to high. After replacing my speakers, I’ve noticed that for the late night listening volume level on PWD is rarely above 25 (PWD is connected directly to Pass XA 30.5). This is obviously far from recommended setting.

As a possible solution, I am thinking of purchasing attenuators (Rothwell XLR attenuators with 20 db attenuation - http://rothwellaudioproducts.co.uk/html/attenuators.html).

However, I am concerned that together with some benefits I might experience also loss of transparency and softening of the transients.

Any thoughts?


#7

You cannot add an attenuator and expect nothing to change. It will get a bit worse. The real challenge is to figure out which is the lesser of two evils: the slight resolution loss from the PWD, or the same loss from the attenuator. Were it me, I’d take a different route - add a decent preamp.

The thing is, a decent preamp with it’s active output buffer, probably sounds better than the attenuator. And if the preamp’s too expensive, stay with the slight loss of resolution at the lowest of bits on the PWD.

At least that’s what I would do.


#8

Thanks Paul!