Need for Digital Volume Control

Ed Zeppeli

Active Member
Hi all,

I am currently using a Sonos Connect into a dbx Venu360 processor for my 2.1 hi fi system.

Sonos analogue output goes into the dbx which then feeds the power amps so currently my setup is converting DA>AD>DA and I'd like to eliminate the first two.

If I go directly out of the Sonos s/pdif into the AES/EBU of the driverack then I will be using only the DA side of the dbx. My concern is that I will then have to use the digital volume control of the Sonos to control volume and I'm worried about resolution loss at lower volumes.

A possible solution is to use an all digital pre-amp/DAC that has a digital output as an intermediary between the two devices in the hopes that it will have a better quality volume control but this seems like a waste of $ since I wouldn't be taking advantage of the DAC feature of it.

Am I missing some simple solution here or are my concerns about using the Sonos Connect for overall volume overblown?


Thanks for reading.

Warren
 
The Connect uses a 24 bit internal buss, and 16 bit data. So, you have 8 bits, or about 48db, of wiggle room before you start dropping bits. That's a pretty big volume adjustment range!
 
The Connect uses a 24 bit internal buss, and 16 bit data. So, you have 8 bits, or about 48db, of wiggle room before you start dropping bits. That's a pretty big volume adjustment range!
That's inexact, as usually.

To OP: When you are doing volume control, you are not affecting the lower bits, you are starting from the "top" bits.
Digital volume control will "push" down the actual bits, leaving the top zeroed. Since most of the delta-sigma DAC chips on the marked will have better precision on the top bits (simplified, those can actually be 4-6 multibit, followed by the noise-shaped one bit, called something like "segment DAC"), that kind of volume control will send zero bits to the top multibit switches, and push more of the signal to the lower delta-sigma converter, actually affect the sound by exposing more of the delta-sigma problems - that is if you you have good quality sources to start with.
An analog volume will take the full-scale digital signal (hence the maximum DAC performance) and will attenuate it. Sure, that might lead to reduced SNR on the following amp, but that's something that our brains can deal easier, actually giving a more "analog" signature.

I recommend analog volume control. That's for example how every AVR on the market does it, nobody uses digital attenuation.
 

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In the real world the Connect seems to handle a wide range of volume control with no discernible degradation of sound quality, I'm happy to report.
 
Based on the comments above, seems that if a company chooses a cheap option, just to boost their bottom line, it is a proof that that's a technically perfect solution.
No technical understanding, no rational discussion, just spewing insults instead as usual. Another one on my ignore list.
Whatever...

Ed, with Cirrus and AKM you can't hear any difference because they didn't apply the multi-segment D-S concept to their DAC's like Texas Instruments /BB or Analog Devices. Basically they sound like a TI/AD at lower digital volumes, but TI/AD are better at higher digital volumes.
 
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In the real world the Connect seems to handle a wide range of volume control with no discernible degradation of sound quality, I'm happy to report.
Yes, I'm currently using it at fixed volume into an integrated amp with analog volume control, but it was completely fine, and couldn't tell any difference whatsoever in quality when I was using the digital volume control.

Enjoy your Connect; I've tried just about every wireless music system out there. Sonos is still far and away the best, most reliable and technologically advanced system out there. Voice control coming soon.
 
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