[PhilNYC]

Was in a discussion on the SlimDevices forum when someone mentioned that muting the analog outputs while using the SqueezeBox as a transport to feed an external DAC made some improvements.  Just tried this, and I was pretty surprised at how noticeable a difference it made...lower noise floor, reduced harshness in the midrange were the two most noticeable things.

Anyways, if you haven't done this, here's what you do:  In the web interface, go to the player's settings. Click on "Audio" and set Preamp Volume Control to 63.0. You might need to stop the audio stream and start it again for the muting to take effect...

[zybar]

Thanks Phil.

I'll try this later tonight and report back.

Is your SB stock or modified? 

George

[lcrim]

Phil:
Thanks, I'm going to try it as well.

[PhilNYC]

My SB2 is stock, but I'm using an Elpac linear power supply.  It's plugged into my Audience AdeptResponse power conditioner...

[zybar]

Was in a discussion on the SlimDevices forum when someone mentioned that muting the analog outputs while using the SqueezeBox as a transport to feed an external DAC made some improvements.  Just tried this, and I was pretty surprised at how noticeable a difference it made...lower noise floor, reduced harshness in the midrange were the two most noticeable things.

Anyways, if you haven't done this, here's what you do:  In the web interface, go to the player's settings. Click on "Audio" and set Preamp Volume Control to 63.0. You might need to stop the audio stream and start it again for the muting to take effect...

What version are you running?

I am still running v6.1.1 ver 15 and I don't have this option.

All I can do is set the volume to full open or let the SB volume control function.

George

[creilly333]

I am running version 6.3.1 and it has it under settings/player settings/audio

I have a stock SB2 with Bolder modified Elpac PS, into Benchmark DAC-1 and Naim NAP250-2 power amp into Quad ESL 57's

Noticed a lowering of the noise floor and much less harshness.

Colin

[PhilNYC]

I'm using SlimServer 6.2.2 - 7135 (Mac version).  The Preamp volume control is right underneath the Digital volume control...

[Paul_Bui]

Was in a discussion on the SlimDevices forum when someone mentioned that muting the analog outputs while using the SqueezeBox as a transport to feed an external DAC made some improvements.  Just tried this, and I was pretty surprised at how noticeable a difference it made...lower noise floor, reduced harshness in the midrange were the two most noticeable things.

Anyways, if you haven't done this, here's what you do:  In the web interface, go to the player's settings. Click on "Audio" and set Preamp Volume Control to 63.0. You might need to stop the audio stream and start it again for the muting to take effect...

Thanks Phil for the tip.  Will try tonight and see how it will improve.

[lcrim]

I didn't have any issues in configuring this to work last night but I stayed up too long listening and I'm bleary today. 
I am not sure why but my first impulse was to lower the volume, like three times.  There is more music coming across the ether(net.)  My SB3 is stock except for a Bolder modded Elpac PS and the digital coax runs to a Scott Nixon Chibi Dac w/ a switch to invert phase if desired.  I thought the improvement was profound.  The PS mods, the change to firmware V15 and muting the analog outs are all pretty dramatic and should be considered as basic to running this architecture.   I don't have a high dollar investment in this setup but it sounds very, very nice.
Thanks for the rec again Phil.

[samplesj]

I'm bumping this back up to the top so no one misses it.  This is an great tweak and even better its totally FREE.

[mcgsxr]

Interesting - I wonder if it is the Slimserver s/w, or the SB Firmware that actually allows this muting to occur.

I ask, because using 6.1.1 Slimserver and V15 firmware, I could NOT achieve this.  The s/w had the option on my PC, but the effect of trying to do it, was null.

I am now running the latest Slimserver release, with V15, but as I use the analog outs, I have not tried to check it yet.

Guess I should, and should post the results!  Another thing on my list for tonight...

[gitarretyp]

Interesting - I wonder if it is the Slimserver s/w, or the SB Firmware that actually allows this muting to occur.

I ask, because using 6.1.1 Slimserver and V15 firmware, I could NOT achieve this.  The s/w had the option on my PC, but the effect of trying to do it, was null.

I am now running the latest Slimserver release, with V15, but as I use the analog outs, I have not tried to check it yet.

Guess I should, and should post the results!  Another thing on my list for tonight...

The preamp volume control was not implemented until a later firmware than V15. You must upgrade the firmware, if you want to use that option (since you're using the analog outs, i'd say stick with V15).

[mcgsxr]

That is what I thought too, but I think I just read another poster suggesting they were successful with V15 firmware doing this... so I thought I would ask.

Hmmn.

[lcrim]

Mark:
I posted that I use V15 firmware and set the analog outs to 63 and heard a considerable difference.  I don't know which release of Slimserver I'm running but it is in the 6's.  I used Mike Galusha's switcher patch to get ver15 firmware in place. 
Since you have the analog mods, why would you want to mute the analog outs?  I use a separate DAC, so for me it makes sense.
Edit:  This is the system where I just removed the preamp and am using the pot on the amp to adjust gain.  I'll have to try resetting the preamp volume control back to 0 and see if I didn't convince myself that the quality gain was caused bt the software setting .

[PhilNYC]

On the SB forum, someone is reporting that they don't notice any difference when changing the setting.  He's using the Toslink output instead of the coax, which makes me speculate why he's not hearing a difference.  Would be curious to hear from others who have tried this, are you using coax or toslink?

[gitarretyp]

Mark:
I posted that I use V15 firmware and set the analog outs to 63 and heard a considerable difference.  I don't know which release of Slimserver I'm running but it is in the 6's.  I used Mike Galusha's switcher patch to get ver15 firmware in place.
Since you have the analog mods, why would you want to mute the analog outs?  I use a separate DAC, so for me it makes sense.
Edit:  This is the system where I just removed the preamp and am using the pot on the amp to adjust gain.  I'll have to try resetting the preamp volume control back to 0 and see if I didn't convince myself that the quality gain was caused bt the software setting .

Out of curiosity, have you checked that the analog outs are actually affected by the change?

[lcrim]

 :oops:There is still output on the analog side even with the preamp volume control set to 63 (fully attenuated.)  I must admit that whatever gains I heard were either illusory or were due to removing the preamp and its gain from the circuit.  Also using SlimServer Version: 6.5b1

[mcgsxr]

I asked, as I have the ability to use the digital output, into a Panny SAXR-15, so if it was really good, I would go through the amp swapping hassles to sort it out etc.

I have not used the modded digital output, I simply had Wayne fully mod it, so that I would have options down the road.

I use V15 firmware, because I hear the best sound via analog outs, with this - perhaps the digital output is also superior, would that have been what you are hearing lcrim?

[lcrim]

Right now I'm wondering if I should reinstall Slimserver and thereby get the latest firmware.  Will the latest firmware with the analog outputs fully attenuated sound better than firmware V15?  While I have several versions of the firmware in the firmware directory, the switcher keeps changing it to V15 after holding down the brightness button to update it.  I'm a bit embarassed but it does sound fine the way it is.
I think that Phil's supposition that by disabling the analog outs you remove a source of RFI makes sense but I would like to test it.
Edit:
Uninstalled Slimserver and switcher program.  Reinstalled Slimserver 6.3.1 w/ firmware Ver.55.  In reconfiguring the sw set the preamp volume control to 63 (full attenuation of the analog output.)  Checked to be sure that there was no output on analog outs.  I am using a coax cable (DH Labs D-75) to a Scott Nixon Chibi Dac with the phase inversion switch set to normal.  Since my credibility is shot, I hesitate to comment on the sound quality but it seems smoother, less harsh overall.  For those using digital out and not analog this tweak (when properly implemented) is probably the way to go.