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btcompute
2007-04-01, 07:30
I realize that most people using this site probably know this already, but I'm posting this in the beginners section in hopes of helping some of the new folks.

If your stereo system has optical inputs, by all means, get and use an optical cable between the squeezebox and the stereo.

I bought one and I'm really surprised at how much difference it made.

More volume, stronger bass, sharper highs, and more dynamic range.

I opted for a relatively cheap cable from Radio Shack ($20 for a 6 ft cable) and it is definitely worth the price.

By the way, I had the option of buying other 6 ft cables for as much as $80. While I doubt that they would produce a noticeable improvement in sound quality, I bet there are folks among us who would disagree.

Anyone care to comment?

Mark Lanctot
2007-04-01, 10:07
Lots more about this at http://wiki.slimdevices.com/index.cgi?BeginnersGuideToConnecting and http://wiki.slimdevices.com/index.cgi?AnalogOrDigital

Mark Lanctot
2007-04-01, 10:10
By the way, I had the option of buying other 6 ft cables for as much as $80. While I doubt that they would produce a noticeable improvement in sound quality, I bet there are folks among us who would disagree.

I'm personally in agreement with you (let me guess, the expensive cables were from Monster) but this is the stuff of 10-page flame wars around here. :-)

So yes, lots of people might agree with you, but a good number won't. BTW $80 cables are cheap in comparison to what's out there.

btcompute
2007-04-01, 10:28
Mark,

On the first link you listed, I found the following comment:
"The Squeezebox can independently control the analog and digital volumes."
No explaination was offered. The volume on the remote seems to control both the analog and Optical outputs equally.

Can you or anyone else explain this?

Thanks,
Brian

Mark Lanctot
2007-04-01, 10:52
I'll edit the wiki.

I guess they're not fully independent - I believe if you set digital volume fixed and adjust the volume, only the analog volume will be adjusted. So it's not entirely independent, but you can have the digital volume fixed at 100% and the analog volume at another level.

ceejay
2007-04-01, 11:23
I realize that most people using this site probably know this already, but I'm posting this in the beginners section in hopes of helping some of the new folks.

If your stereo system has optical inputs, by all means, get and use an optical cable between the squeezebox and the stereo.

I bought one and I'm really surprised at how much difference it made.

More volume, stronger bass, sharper highs, and more dynamic range.

I opted for a relatively cheap cable from Radio Shack ($20 for a 6 ft cable) and it is definitely worth the price.

By the way, I had the option of buying other 6 ft cables for as much as $80. While I doubt that they would produce a noticeable improvement in sound quality, I bet there are folks among us who would disagree.

Anyone care to comment?

Just a couple of comments... you say there was more volume, so I'm guessing that you switched from an analog connection to a digital(optical) one. If that's the case then it is certainly *not* a reasonable generalisation that the digital(optical) connection will sound better. If you make this change then you are changing from using the DAC in the SB to using the DAC in your stereo, which may or may not be better.

If your stereo converts all analog inputs to digital and then back to analog again after processing, which many do, then indeed it is highly likely that using the digital connection will sound better as you would be cutting out a A/D - D/A step.

Its also worth pointing out that if there was more volume, then it would almost always sound better in the ways you mention just because of the volume change. You should only try to make comparisons if you've attempted to match the volume.

If my inference was wrong and you switched from a digital(coax) to a digital(optical) connection then I don't understand how the volume would be better. Though there is certainly room for a bit of controversy over which might be better in various circumstances.

HTH
Ceejay

btcompute
2007-04-01, 11:25
OK,
What is it that I am missing this time.

What do you mean by "set digital volume fixed" and "you can have the digital volume fixed at 100% and the analog volume at another level".
The only controls I can find are the volume control on the remote, and the corresponding control on the Music Control side of the Slimserver interface. Both controls seems to adjust as you adjust either one, and they appear to control analog and digital volume equally.

Mark Lanctot
2007-04-01, 11:42
OK,
What is it that I am missing this time.

What do you mean by "set digital volume fixed" and "you can have the digital volume fixed at 100% and the analog volume at another level".
The only controls I can find are the volume control on the remote, and the corresponding control on the Music Control side of the Slimserver interface. Both controls seems to adjust as you adjust either one, and they appear to control analog and digital volume equally.

Go to the SlimServer web interface.

Player Settings - Audio.

My SlimServer is down at the moment, but if you scroll around a bit you should see an option to set digital output volume fixed.

When you do this, it will keep the digital volume at 100% no matter what the player reports. Adjusting the player volume will then adjust the analog volume only while the digital volume remains fixed at 100%.

btcompute
2007-04-01, 11:50
Just a couple of comments... you say there was more volume, so I'm guessing that you switched from an analog connection to a digital(optical) one. If that's the case then it is certainly *not* a reasonable generalisation that the digital(optical) connection will sound better. If you make this change then you are changing from using the DAC in the SB to using the DAC in your stereo, which may or may not be better.

If your stereo converts all analog inputs to digital and then back to analog again after processing, which many do, then indeed it is highly likely that using the digital connection will sound better as you would be cutting out a A/D - D/A step.

Its also worth pointing out that if there was more volume, then it would almost always sound better in the ways you mention just because of the volume change. You should only try to make comparisons if you've attempted to match the volume.

If my inference was wrong and you switched from a digital(coax) to a digital(optical) connection then I don't understand how the volume would be better. Though there is certainly room for a bit of controversy over which might be better in various circumstances.

HTH
Ceejay

Here is what I have done to compair the Squeeze box to my cd player, and analog output to the optical cable:

I connected the Squeezebox to the receiver using both analog cables and the optical cable.

On the receiver, I can switch back and forth between the two inputs. The optical input sounds much better, and a little louder to all who have listened to it.

Also, I can do a direct camparison between the squeezebox and the cd player.
With the squeezebox volume turned all the way up, the analog inputs seem to produce a little less volume than the cd player.
With the optical cable, the volume is a little stronger than the cdplayer. I have to cut back a little on the squeezebox volume to equalize it to the cd player.
With the optical input and the volume equalized, we hear no consistant difference in sound quality between the squeezebox and the cd player.

jeffmeh
2007-04-01, 13:36
Here is what I have done to compair the Squeeze box to my cd player, and analog output to the optical cable:

I connected the Squeezebox to the receiver using both analog cables and the optical cable.

On the receiver, I can switch back and forth between the two inputs. The optical input sounds much better, and a little louder to all who have listened to it.

Also, I can do a direct camparison between the squeezebox and the cd player.
With the squeezebox volume turned all the way up, the analog inputs seem to produce a little less volume than the cd player.
With the optical cable, the volume is a little stronger than the cdplayer. I have to cut back a little on the squeezebox volume to equalize it to the cd player.
With the optical input and the volume equalized, we hear no consistant difference in sound quality between the squeezebox and the cd player.

The point made earlier is that if you do not match the volumes, the comparison is invalid. If you A/B tested between a lower volume and a higher volume on the same source, then you would probably like the higher volume better, and you could certainly discern the difference. If you match the volumes from different sources and can discern a difference, then you have a valid comparison.

btcompute
2007-04-01, 13:51
If you match the volumes from different sources and can discern a difference, then you have a valid comparison.

When I compared the optical output from the Squeezebox to the cd player, I was able to equalize the volume.

I consider that a valid comparison.

jeffmeh
2007-04-01, 14:01
When I compared the optical output from the Squeezebox to the cd player, I was able to equalize the volume.

I consider that a valid comparison.

I would consider it valid for your purposes also. How did you connect the CD player to the receiver? If that is through analog, then you are comparing your CD player's DAC to your receiver's DAC. If it is digital, then you are comparing different sources (CD player through its digital connection, SB through its optical digital connection), both using the receiver's DAC.

btcompute
2007-04-01, 14:06
I would consider it valid for your purposes also. How did you connect the CD player to the receiver? If that is through analog, then you are comparing your CD player's DAC to your receiver's DAC. If it is digital, then you are comparing different sources (CD player through its digital connection, SB through its optical digital connection), both using the receiver's DAC.

My CD player has only analog outputs.

jeffmeh
2007-04-01, 14:20
My CD player has only analog outputs.

OK, then you are really comparing the [SB3 > optical > receiver DAC > receiver pre-amp/amp] to the [CD player transport/DAC > analog > receiver pre-amp/amp].

Also, when you level the volume between the comparisons, are you doing it "by ear" or with a sound pressure level meter? If "by ear" I would not consider the comparison valid, as you would be using the same instrument (your ears) to prepare the evaluation and to do the evaluation. That would be somewhat like evaluating the accuracy of an oven thermometer by bringing the oven up to 350deg F as measured by that thermometer, then declaring it accurate because it reads 350deg F.

Of course, at the end of the day what really matters is that you are enjoying the sound, regardless of how you got there.

Mark Lanctot
2007-04-01, 14:28
Also see http://wiki.slimdevices.com/index.cgi?AVReceivers - it could depend which mode you play the music back.