[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Patrick Dixon;148499 Wrote: Why on earth are people so obsessed with this volume control thing?Hi. I've just been searching for discussions on the use of the SB volume control, and this is really helpful. The reason I'm so interested, is that with this knowledge, I can maximise the quality of the music I listen to, without having to go shopping for more exotic equipment. I'd like my stereo to produce the best sound it's capable of, and while I like to trust my ears when it comes to audio taste, I'm not capable of blind testing and spotting the difference between adjusting the volume on my SB or pre-amp. So there's really two 'optimum' ways to go:- (1) Use a pre-amp, max the SB volume and adjust volume using the preamp control, (2) Feed SB directly to power amp, set a sensible volume range using attenuators or whatever, and use the SB digital volume between 40 and 100 for critical listening. Dam. My main system has a TAG DAC, and Exposure XIX preamp, to active speakers. I would follow (1) above, but I have no remote for the preamp, so I'm doing a mixture of 1 2. -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
rjplummer;150130 Wrote: Hence the suggestion that you can drop 30dB using the digital volume control without impact.Err, no. The -30db suggestion comes from the fact that the SB has been carefully designed not to drop any digital resolution until this point. Please feel free to search the forum for more info on this. rjplummer;150130 Wrote: In fact, with 16-bit audio sources (will the SB accept any 24-bit formats?) You can only drop 24dB before you start losing information.This is not correct. You are assuming that drops are in convienient binary divisions (which of course they aren't). rjplummer;150130 Wrote: You probably very rarely need more than a 24dB range in any given situation.At least there's one thing in your post I can agree with! -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Patrick Dixon;150167 Wrote: Err, no. The -30db suggestion comes from the fact that the SB has been carefully designed not to drop any digital resolution until this point. Careful design really doesn't have much to do with it. It's all about having 8 spare bits. I realized that I wasn't thinking in stereo, so 0.5dB would be 0.25dB/channel. So you could drop the volume much more before you lose bits. Patrick Dixon;150167 Wrote: This is not correct. You are assuming that drops are in convienient binary divisions (which of course they aren't). DACs convert numbers into voltages, so every bit does equal 3dB (Actually 3.010...dB). That's why people talk about CDs as having a S/N ratio of 96dB (16 bits x 2 channels x 3dB). If there's anything carefully designed, it would be that each volume increment corresponded to .0502dB (1/6 of a one-bit drop) rather than precisely 0.5dB. But this would be the easiest way to implement it. Of course at some point you have to worry about the noise level of the circuit between your SB and pre-AMP. But that doesn't have anything to do with the digital attenuation. -- rjplummer rjplummer's Profile: http://forums.slimdevices.com/member.php?userid=8192 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
rjplummer;150288 Wrote: Careful design really doesn't have much to do with it. It's all about having 8 spare bits. I realized that I wasn't thinking in stereo, so 0.5dB would be 0.25dB/channel. So you could drop the volume much more before you lose bits. DACs convert numbers into voltages, so every bit does equal 3dB (Actually 3.010...dB). That's why people talk about CDs as having a S/N ratio of 96dB (16 bits x 2 channels x 3dB). If there's anything carefully designed, it would be that each volume increment corresponded to .0502dB (1/6 of a one-bit drop) rather than precisely 0.5dB. But this would be the easiest way to implement it. Of course at some point you have to worry about the noise level of the circuit between your SB and pre-AMP. But that doesn't have anything to do with the digital attenuation. Calculation of dynamic range has nothing to do with the fact that it's stereo (or a multichannel system would have enormous dynamic range!): http://en.wikipedia.org/wiki/Decibel#6_dB_per_bit -- P Floding P Floding's Profile: http://forums.slimdevices.com/member.php?userid=2932 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
rjplummer;150288 Wrote: Careful design really doesn't have much to do with it. It's all about having 8 spare bits. I realized that I wasn't thinking in stereo, so 0.5dB would be 0.25dB/channel. So you could drop the volume much more before you lose bits.I'm sorry but you are just completely wrong! (I'm only bothering to reply in case someone who doesn't know any better takes you seriously.) rjplummer;150288 Wrote: DACs convert numbers into voltages, so every bit does equal 3dB (Actually 3.010...dB). That's why people talk about CDs as having a S/N ratio of 96dB (16 bits x 2 channels x 3dB). If there's anything carefully designed, it would be that each volume increment corresponded to .0502dB (1/6 of a one-bit drop) rather than precisely 0.5dB. But this would be the easiest way to implement it. Of course at some point you have to worry about the noise level of the circuit between your SB and pre-AMP. But that doesn't have anything to do with the digital attenuation.Yeah, thanks for the lesson. (BTW it's ~6dbs per bit (20 x log10), so thats 16 x 6 = 96dbs per channel - stereo has nothing to do with it!) -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Things are a bit more complicated. With analog systems, you generally want to keep the voltage as high as you can for as much of the circuit as you can. Hence the suggestion to only use the preamp volume control. But with high-quality equipment and cables, the signal-to-noise ratio means we can do quite a bit of attenuating before we need to worry about the noise. That amount's about 30dB. Hence the suggestion that you can drop 30dB using the digital volume control without impact. In fact, with 16-bit audio sources (will the SB accept any 24-bit formats?) You can only drop 24dB before you start losing information. And the SB volume control likely offers you better control at low volumes that your preamp volume control. I'd suggest you use your preamp volume control (with the SB set at 100) to set your max desired volume for the listening session, then use the SB volume control to make adjustments during the session. You probably very rarely need more than a 24dB range in any given situation. -- rjplummer rjplummer's Profile: http://forums.slimdevices.com/member.php?userid=8192 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
I'm new to the SB3, and I think this is great information to know about the ~40 volume value. Thanks to all previous posters in this thread! So the idea is, that losing some SNR as you decrease volume between 100 and 40 won't really matter much, because (after all) the decreased volume means you probably can't hear/notice this difference - is this correct? -- NewBuyer NewBuyer's Profile: http://forums.slimdevices.com/member.php?userid=7862 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
NewBuyer;148484 Wrote: So the idea is, that losing some SNR as you decrease volume between 100 and 40 won't really matter much, because (after all) the decreased volume means you probably can't hear/notice this difference - is this correct?Not really. All volume controls will lose some signal to noise ratio (as will all active stages), but by running the SB volume between 40 and 100 and not using a pre-amp, you swap the SNR loss in the preamp gain stage and volume control, for a SNR loss in the SB DAC. It's swings and roundabouts - but the swings and roundbaouts are not always quite equal (IYSWIM). With SB volumes below 40, you are also losing some digital resolution (which adds to the overall SNR degradation), but digital artifacts are usually less 'graceful' than analogue ones. In general, if you have your system's gain reasonably well set up, at -30dBs (below 40 volume), you not really listening critically anyway, and other system effects will most likely dominate. So there's really two 'optimum' ways to go:- (1) Use a pre-amp, max the SB volume and adjust volume using the preamp control, (2) Feed SB directly to power amp, set a sensible volume range using attenuators or whatever, and use the SB digital volume between 40 and 100 for critical listening. Depending on your system and the quality of the pre-amp, (1) or (2) may be a better approach than the other. -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Patrick Dixon;148499 Wrote: ...by running the SB volume between 40 and 100 and not using a pre-amp, you swap the SNR loss in the preamp gain stage and volume control, for a SNR loss in the SB DAC... Again limiting the question to volume levels from max 100 down to around 40: Does the SNR loss becomes less noticeable to the listener, as the volume is decreased through this range (i.e. less volume, so less quality loss perception)? -- NewBuyer NewBuyer's Profile: http://forums.slimdevices.com/member.php?userid=7862 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
NewBuyer;148577 Wrote: Again limiting the question to volume levels from max 100 down to around 40: Does the SNR loss becomes less noticeable to the listener, as the volume is decreased through this range (i.e. less volume, so less quality loss perception)? Less noticeable than what? I guess if you have the volume so low you can't hear any music, then you wouldn't notice any loss of quality if you lower it some more. Is that what you're getting at? Why on earth are people so obsessed with this volume control thing? -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Patrick Dixon;148620 Wrote: Why on earth are people so obsessed with this volume control thing? And why are you testy about people being obsessed with this volume control thing? Seriously, your expertise is a real asset to this forum. If you would be so kind as to answer the couple of follow-up questions I have posted on this thread: http://forums.slimdevices.com/showthread.php?t=28884 I promise never to bug you about volume control again! -- boybees boybees's Profile: http://forums.slimdevices.com/member.php?userid=1153 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
some education guy's why does the signal begin to deteriorate? I assume for the highest quality you are best to disable the digital volume control and use an external amp to boost/lower the signal? Michael -- dlite dlite's Profile: http://forums.slimdevices.com/member.php?userid=4885 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
You mean integrated amp, right? There's a big difference between an integrated amp -- it includes a preamp or line stage component -- and an amplifier (or power amplifier). Not to be a pest, but it seems like people on this forum confuse the two. Anyway, yes: the commonly recommended method is to fix the digital volume control at the maximum setting, through Slim Server, and then use the line stage volume control. But, as patrick pointed out, you're safe in the range of 40-100. For kicks, I've listened to it lower than that and found very little, if any, discernable difference. In short, there is nothing to get anxious about. For peace of mind, just set it at max and use your volume control on another device for attenuation. dlite;148123 Wrote: some education guy's why does the signal begin to deteriorate? I assume for the highest quality you are best to disable the digital volume control and use an external amp to boost/lower the signal? Michael -- highdudgeon Relax. It's about the music. highdudgeon's Profile: http://forums.slimdevices.com/member.php?userid=2195 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
highdudgeon;148149 Wrote: You mean integrated amp, right? There's a big difference between an integrated amp -- it includes a preamp or line stage component -- and an amplifier (or power amplifier). Not to be a pest, but it seems like people on this forum confuse the two. Anyway, yes: the commonly recommended method is to fix the digital volume control at the maximum setting, through Slim Server, and then use the line stage volume control. But, as patrick pointed out, you're safe in the range of 40-100. For kicks, I've listened to it lower than that and found very little, if any, discernable difference. In short, there is nothing to get anxious about. For peace of mind, just set it at max and use your volume control on another device for attenuation. Thanks I meant a pre amplifier actually, I do understand the difference well but am a little unsure why the digital signal deteriorates at the lower volumes is the data being trimmed? Sorry about being a little vague it was late at ight with a moderate amount of drinks under the belt. I am actually trying to work out what the best solution is for me, I have some efficient speakers Zu Druids at 101db, Belcanto REF1000 power amps and PRE6 pre amp. Because of the efficiency of the speakers the preamp is some times set to 25 out 200 on the volume scale. This concerns me a little as unity gain is 100 so i am worried that I am losing some quality because of the level of attentuation. I am aware the volume in the preamp works differently to the SB but am not versed significantly enough in the operation of the various types of volume controls. -- dlite dlite's Profile: http://forums.slimdevices.com/member.php?userid=4885 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
You have a good preamp. Just max out the digital volume in slim server, use the volume control on your pre, and call it a night. That's all you need to know. dlite;148394 Wrote: Thanks I meant a pre amplifier actually, I do understand the difference well but am a little unsure why the digital signal deteriorates at the lower volumes is the data being trimmed? Sorry about being a little vague it was late at ight with a moderate amount of drinks under the belt. I am actually trying to work out what the best solution is for me, I have some efficient speakers Zu Druids at 101db, Belcanto REF1000 power amps and PRE6 pre amp. Because of the efficiency of the speakers the preamp is some times set to 25 out 200 on the volume scale. This concerns me a little as unity gain is 100 so i am worried that I am losing some quality because of the level of attentuation. I am aware the volume in the preamp works differently to the SB but am not versed significantly enough in the operation of the various types of volume controls. -- highdudgeon Relax. It's about the music. highdudgeon's Profile: http://forums.slimdevices.com/member.php?userid=2195 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Well, I would argue, that if someone wants the whole story, theres no real need to keep it a secret! The SB (and Transporter) volume controls work on the digital signal, before it goes to the DAC. The usual problem with this, is that as you turn the volume down, you decrease the number of bit's in the digital word, and thus increase the distortion in your signal. This is why some people (myself included) have a phobia about digital domain volume control. In the case of the SB though, they've been clever. By using a 24 bit DAC, to convert 16 bit CD data, they've bought themselves 8 extra bits to play with. The software controlling the volume makes sure that no bits are lost until you get to ~40. You will get a decrease in Signal to Noise ratio as you turn the volume down, but you don't get distortion due to lost data bits. Hope this helps! Dave -- DCtoDaylight DCtoDaylight's Profile: http://forums.slimdevices.com/member.php?userid=7284 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
boybees;147581 Wrote: Slim Server 6.5: If I have the volume control set at 80 instead of 100, does this take out information from the digital signal?No - it just gives you a slight reduction in the actual signal to noise ratio at the DAC. -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
Patrick Dixon;147622 Wrote: No - it just gives you a slight reduction in the actual signal to noise ratio at the DAC. Thanks. Are you aware of at what point on the volume scale it does begin to degrade the digital signal? -- boybees boybees's Profile: http://forums.slimdevices.com/member.php?userid=1153 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Effect of SB3 volume control
boybees;147688 Wrote: Thanks. Are you aware of at what point on the volume scale it does begin to degrade the digital signal? -30dbs - which equals 40 on the 100 point volume scale. -- Patrick Dixon www.at-tunes.co.uk Patrick Dixon's Profile: http://forums.slimdevices.com/member.php?userid=90 View this thread: http://forums.slimdevices.com/showthread.php?t=28834 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
