[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Patrick Dixon;165314 Wrote: > The normal approach with a 16 bit original represented as a 24 bit > signal, would be to make the bottom 8 bits 0s - so using the volume > control, some of those bits may be turned in 1s, but no 1s will ever be > required lower than the 24th bit. If you then throw away the bottom 4 > of those 24 bits, you may be throwing away some 1s, and therefore some > information. If you use all of the 24 bits you aren't throwing away > any information.This is very useful, thanks. I had wrongly assumed that as > you reduced volume, you lost a bit of information at a time, and if you didn't go below the 16 bit original, which DAC you used would be irrelevant. If we had represented the original 16 bit signal as 20 bits, I assume we'd be able to slightly reduce the volume and pass to an external 20 bit DAC, without losing information (although reducing SNR - which I'm not saying is irrelevant, but in my case, I use a pre amp to set my maximum volume, and then use the sq box to adjust slightly for convenience) -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
USAudio;165508 Wrote: > the C-100 integrated seems to produce an improved sound over connecting > the SB3 directly to the A-100 amp. Apples and Oranges IMHO. As we've learnt, relying on the digital volume controls is a handicap to the Sb3's SNR. A proper comparison might be the integrated amp or a seperate amp+pre versus fixed/stepped passive attenuators and limited use of the volume control. The digital volume control is great, and with the integrated you should not be afraid to use it for casual to semi serious listening. When you're all ears though, setting the Sb3 to max is the best idea, and if a comparison is to be made it should be at maximum digital volume for both setups. -- Skunk Skunk's Profile: http://forums.slimdevices.com/member.php?userid=2685 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Phil Leigh;165461 Wrote: > ... all in all, it's probably best just to alter level in the analogue > domain - at least we all get to sleep nights! ... You got that right Phil! I've been struggling over this issue for awhile now with the new system I've been putting together. I came to the same conclusion the other day and decided to replace my PS Audio A-100 amp with their integrated C-100. I was connecting the SB3 directly to the A-100 amp. I received the new unit today and, while I've only had the unit a few hours, the C-100 integrated seems to produce an improved sound over connecting the SB3 directly to the A-100 amp. Some of my recordings that sounded a bit thin before now sound more substantial. -- USAudio USAudio's Profile: http://forums.slimdevices.com/member.php?userid=8580 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Yes sorry I didn't (obviously!) mean upsample...what is the correct term for altering the bit-depth of a sample? "re-fathoming"? a-ha!... I get it (at last) you can alter the extra bits as much as you like until you happen to cause an effect on one of the original 16...and once you do that you lose information? - that all makes perfect sense. all in all, it's probably best just to alter level in the analogue domain - at least we all get to sleep nights! Cheers Phil -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Phil Leigh;165422 Wrote: > So Patrick - to (try and) cut a long story short... ... if only. Phil Leigh;165422 Wrote: > In the SB implementation, if you take a 16-bit file, the SB internally > upsamples to and outputs at 24 bitsErr, that's not upsampling - upsampling is > something completely different! Phil Leigh;165422 Wrote: > ...if those 24 bits are sent to a 20-bit DAC do you lose any information > (at full volume). > > My guess is NO since the original 16 bits are preserved (within the > 20). This is surely the case otherwise the SB would only be "bit > perfect" with 24-bit DACs which is not the case AFAIK.Please see my previous > post - at full volume the bits are passed through unchanged - therefore there can be no loss of information. Phil Leigh;165422 Wrote: > I'm happy with the idea that any lowering of the digital volume > potentially loses information, regardless of bit-depthIt doesn't! (It has > implications on the SNR when the signal is converted back to analogue though.) -- 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=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
So Patrick - to (try and) cut a long story short... In the SB implementation, if you take a 16-bit file, the SB internally upsamples to and outputs at 24 bits...if those 24 bits are sent to a 20-bit DAC do you lose any information (at full volume). My guess is NO since the original 16 bits are preserved (within the 20). This is surely the case otherwise the SB would only be "bit perfect" with 24-bit DACs which is not the case AFAIK. I'm happy with the idea that any lowering of the digital volume potentially loses information, regardless of bit-depth -- Phil Leigh Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Triggaaar;165125 Wrote: > Ignoring SNR, what is confusing me particularly, is how according to the > statements I've quoted, reducing the volume to a certain point will not > result in losing original information if using a 24 bit DAC, but it > will if using an external 20 bit DAC. The volume control settings are carefully chosen so that with a 16 bit original no bits lower than the 24th one will be changed. The normal approach with a 16 bit original represented as a 24 bit signal, would be to make the bottom 8 bits 0s - so using the volume control, some of those bits may be turned in 1s, but no 1s will ever be required lower than the 24th bit. If you then throw away the bottom 4 of those 24 bits, you may be throwing away some 1s, and therefore some information. If you use all of the 24 bits you aren't throwing away any information. It may be helpful to think of SNR as an 'analogue' thing and information as a 'digital' thing. The digital signal in this case is a representation of an analogue signal, and how you represent it digitally has an implication on the maximum SNR attainable in the analogue domain. In the digital domain you can represent and manipulate the signal in all kinds of different ways, but so long as you don't discard any bits, you retain all the information and you can still get back to the original digital signal. -- 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=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Ignoring SNR, what is confusing me particularly, is how according to the statements I've quoted, reducing the volume to a certain point will not result in losing original information if using a 24 bit DAC, but it will if using an external 20 bit DAC. -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
There are two different issues here, and I think they might be causing some confusion. One is whether information is lost when you lower the volume; in other words, is it possible to reconstitute the original signal from the signal with lowered volume? The answer to this in the case of the SB (and probably TP) is that there is a certain range from 100 down for which this is possible, but that below some setting it isn't any longer (I think this is 35dB, so to lowest setting is 30 on the 100 point scale). But of course this is not a question of much practical interest. Another question is signal/noise ratio of the signal going to a DAC. In that case the issue above is probably tototally unimportant, and the only issue is how much of the dynamic range of the DAC is being used. Any digital signal with lower than max volume will suffer reduced S/N, and it shouldn't matter much, if at all, if it is slightly below 30 or slightly above 30. -- opaqueice opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
If you have ripped a file (say FLAC) from a CD, and then stream it from the PC to your squeezebox, does the squeezebox receive a 16 bit signal, and convert it, or does the slimserver stream a 24 bit signal? -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Triggaaar;164989 Wrote: > > "Yes, you only maintain all the resolution of the original 16 bits by > using all 24 bits - so truncating to 20 will loose you some > information." a 24-bit input value some of the lower attentuation values will not end up truncating any bits, in other words. Thats part of why the input value is 24 bits even though the data is only 16 bits. > > reducing the digital volume will NOT take out information from the > original signal, providing the input signal is 16 bit audio and you > don't go lower than (IIRC) -35dB > The same thing as above: the original value on a CD is only 16 bits. So if you take a 16 bit value, and left-shift it (effectively) 8 times, rotating 0's into the low order bits, you have more wiggle room. Or if binary isnt your cup of tea: think of it in decimal. You have a number, say, between 00 and 99, if you make it between 000 and 990, by multiplying by 10, you have a bit extra resolution when you do division without resorting to fractions. In this case, it actually gets you through the first N steps of volume attenuation without any truncation. -- snarlydwarf snarlydwarf's Profile: http://forums.slimdevices.com/member.php?userid=1179 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Thanks for your time trying to help me understand this. I am sorry if everyone else thinks this is clear, and I'm confusing the issue. Patrick Dixon;164966 Wrote: > No, I'm not saying that! At 100, the digits will be passed through > untouched, it's only if you reduce volume you can loose resolution.Yes, I > realise that at 100 volume, the squeezebox will pass the digits through without degrading the signal - I am trying to understand the following two points, which to me, seem contradictory (ignoring reduced SNR): "Yes, you only maintain all the resolution of the original 16 bits by using all 24 bits - so truncating to 20 will loose you some information." and reducing the digital volume will NOT take out information from the original signal, providing the input signal is 16 bit audio and you don't go lower than (IIRC) -35dB Thanks -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Patrick Dixon;164966 Wrote: > Sorry about that. > > Yes - providing the input signal is 16 bit audio and you don't go lower > than (IIRC) -35dB. The bits don't have the same value that they had before you shifted them!! Attenuate by 6db and you're then using only half of the system's output range - you're closer to the noise floor and you have only half of the available "steps". I don't know what it means to "slightly reduce" the SNR. The reduction is exactly equal to the amount of attenuation. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Triggaaar;164952 Wrote: > > I'm now more confused than I started.Sorry about that. Triggaaar;164952 Wrote: > So Patrick is saying that reducing the digital volume will NOT take out > information from the original signal, just slightly reduce the SNR.Yes - > providing the input signal is 16 bit audio and you don't go lower than (IIRC) -35dB. Triggaaar;164952 Wrote: > And Patrick is saying that even if you leave the volume at 100, you will > lose original resolution of the 16 bits if you have a 20 bit DAC (as you > are sending it a 24 bit signal).No, I'm not saying that! At 100, the digits > will be passed through untouched, it's only if you reduce volume you can loose resolution. Triggaaar;164952 Wrote: > > The one bit that does seem clear, is that digitally reducing the > volume, prior to converting to anologue, reduces the SNR.Almost everything > you do to an analogue signal reduces its SNR too, so what I'm trying to say is that digital volume control vs analogue volume control is something of a trade-off. -- 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=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
>From another volume thread (2 months old) 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? Patrick Dixon;147622 Wrote: > No - it just gives you a slight reduction in the actual signal to noise > ratio at the DAC. and now, in response to Sean's comments "This is completely, 100% wrong. It doesn't matter how many people say this, it is still wrong": Patrick Dixon;164921 Wrote: > Yes, you only maintain all the resolution of the original 16 bits by > using all 24 bits - so truncating to 20 will loose you some > information. > I'm now more confused than I started. So Patrick is saying that reducing the digital volume will NOT take out information from the original signal, just slightly reduce the SNR. And Patrick is saying that even if you leave the volume at 100, you will lose original resolution of the 16 bits if you have a 20 bit DAC (as you are sending it a 24 bit signal). I apologise if I have miss interpreted everything, but it seems that Sean and Patrick are saying completely different things. The one bit that does seem clear, is that digitally reducing the volume, prior to converting to anologue, reduces the SNR. -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Patrick Dixon;164921 Wrote: > AFAIK each step corresponds to 0.5dB. So 90 is -5dB, 80 is -10dB and 70 > is -15dB. You're correct, my bad. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
seanadams;164687 Wrote: > This is completely, 100% wrong. It doesn't matter how many people say > this, it is still wrong. Yes, you only maintain all the resolution of the original 16 bits by using all 24 bits - so truncating to 20 will loose you some information. seanadams;164681 Wrote: > You _ALWAYS_ lose SNR and dynamic range. The "you still have all the > bits" concept is completely flawed.Well not -completely- flawed ;-) Any > digital signal which doesn't swing the whole numerical range available to it, will loose some SNR (compared to the maximum available), at the DAC. However, this 'loss' of SNR may or may not be better than any SNR loss in a subsequent buffer and volume control circuit. seanadams;164681 Wrote: > > Use the digital volume for day-to-day adjustment within your normal > listening range, not to compensate for a badly matched system.Absolutely. seanadams;164763 Wrote: > The new 0 to 100 scale is, I believe, true decibels. (In the past when > we used only 40 steps, it was a more complicated curve designed to > stretch out the low end of the range). So -10 corresponds to 90, -20 to > 80, and -30 to 70. > Well it's your product (nice title BTW), but AFAIK each step corresponds to 0.5dB. So 90 is -5dB, 80 is -10dB and 70 is -15dB. The previous 0-40 range gave steps of 1.25dB each. -- 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=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
seanadams;164816 Wrote: > No - you are making this FAR more complicated than it is. Forget about > decibels! > > All you do is set the jumpers so that when transporter is playing at > full volume, you are at the maximum listening level you'd want to use. > Just start at -30 and move them up towards 0, until you reach your max > listening level. That is really all there is to it. > > If you are already using a preamp, or if your amplifier has gain > controls, then you should use those controls and don't touch the > jumpers. > > What you are trying to avoid is a situation where you are at your > maximum listening level with the volume bar only half way up. This is > what might happen if you connected transporter directly to an amp. > That's when you need to change the jumpers. Thanks Sean, That's a simple way of setting and understanding! Bill -- mr_bill mr_bill's Profile: http://forums.slimdevices.com/member.php?userid=6737 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
wshields;164821 Wrote: > How many other CEOs are on the company forums on Christmas helping their > customers? Well, actually I'm not anymore. Title updated. :) -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Sean, Thanks so much for clearing these questions up. How many other CEOs are on the company forums on Christmas helping their customers? Outstanding service for us. Thanks again. Walt Shields -- wshields wshields's Profile: http://forums.slimdevices.com/member.php?userid=8639 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
mr_bill;164796 Wrote: > Sean, > So, if I set up my inernal jumpers on my Benchmark Dac (or Transporter > for that matter) so if the SB3 volume reads 70 and my decibel meter in > room reads 70 db then am I set up and getting maximum SNR, resolution > and performance? Would I still need a preamp performance related to > matching or volume? > Thanks and I think I finally understand, > Bill No - you are making this FAR more complicated than it is. Forget about decibels! All you do is set the jumpers so that when transporter is playing at full volume, you are at the maximum listening level you'd want to use. If you are already using a preamp, or if your amplifier has gain controls, then you should use those controls and don't touch the jumpers. What you are trying to avoid is a situation where you are at your maximum listening level with the volume bar only half way up. This is what might happen if you connected transporter directly to an amp. That's when you need to change the jumpers. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
I think the easiest way to understand this is to forget about numbers, decibels, and bits per sample for a minute, and just think about what's coming out of the DAC. To oversimply only slightly: there are two things always coming from the DAC. 1) signal and 2) noise. The level of the noise output *stays the same* no matter what signal level is being produced. That is really important to understand! When the DAC is making a loud signal, there is a *lot* of signal and a *little* noise. That's a high SNR, which is good. However, when the DAC is making a quiet signal, you have a *little* signal and a *little* noise. If we now consider the noise level *in relation to* the signal level, the noise is now louder. The noise level hasn't gone up in absolute terms (eg volts), but relative to the signal it has, so you now have a bad SNR. Now consider a simple resistor attenuator being fed by a loud (good SNR) signal from the DAC. When the voltage passes through the resistor divider, *everything* gets attenuated - the signal and noise together. You have the same* SNR coming out of the divider as you had going in, i.e., the DAC's optimal SNR is preserved. OK, now back to bits per sample. As you can see, the above effects really don't have much at all to do with bits per sample. We could send a million bits per sample, and it would still be the same. So why does bit depth matter? What is the significance of 16 vs 24 bit? What matters is that we send enough bits per sample that the DAC's full dynamic range is utilized. It is important to realize that the DAC's dynamic range is finite, and is less than its input word size - more like 20 bits, since it is limited by its output noise level. By "expanding" a 16 bit signal to 24 bit, all we are doing is saying "these 16 bits go in the most significant slots of the 24 bit word". We haven't improved the SNR of the signal, any more than you can "enhance" a digital photo the way they do on CSI. If we attenuate the 16 bit signal, yes, the zeroes and ones will migrate down into the least significant bits of the 24 bit word, and yes, if we still "have all the bits" we could then mathematically go in reverse and get back to the same data. But that is not what the DAC does with the signal! The bits represent a smaller signal now than they did before. We still have exactly the same decreasing SNR effect. Sending 24 bits into the DAC just means we aren't making it any worse than it already is. We haven't "bought more headroom"... it does NOT mean that those first 8 bits of attenuation are "free". To prove this, you could play a sine wave through the DAC and measure the SNR at each volume step. We would expect to see the SNR decrease as the volume is decreased. If there were anything special about the point where we start "losing bits", or if we were really getting "extra headroom", then the plot would decrease slowly (or not at all) until it reaches that point, and then there would be an inflection. However, that is not what you'll see. The SNR will simply decrease with the signal level, all the way down. I hope this helps... for extra credit maybe someone will try testing this? -* Actally, there are a number of secondary effects which reduce the SNR by the time it gets through the amplifier, but these are vanishingly small in comparison.- -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Okay, I didn't realize Transporter changed volume in digital when outputting thru analog outs. Now, I run the transporter thru an integrated amp. So I am concluding I should adjust volume using the amps volume controls. One question I still have is how should I decide if I should use the Transporter's jumpers to attenuate the volume before it reaches the amps volume control. Any one have any suggestions? Thanks again. Walt -- wshields wshields's Profile: http://forums.slimdevices.com/member.php?userid=8639 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
seanadams;164763 Wrote: > The new 0 to 100 scale is, I believe, true decibels. (In the past when > we used only 40 steps, it was a more complicated curve designed to > stretch out the low end of the range). So -10 corresponds to 90, -20 to > 80, and -30 to 70. > > > > Correct - exactly the same concept. Sean, So, if I set up my inernal jumpers on my Benchmark Dac (or Transporter for that matter) so if the SB3 volume reads 70 and my decibel meter in room reads 70 db then am I set up and getting maximum SNR, resolution and performance? Would I still need a preamp performance related to matching or volume? Thanks and I think I finally understand, Bill -- mr_bill mr_bill's Profile: http://forums.slimdevices.com/member.php?userid=6737 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
That is one tough read. It doesn't help that our friend Dan is a bit of a prickly pear. If the link doesn't work, look for the thread titled "DA10 for the main pair in a 5.1 setup". -Ben -- Ben Diss SB3 -> Lavry DA10 -> BAT VK-31SE -> Halo A21 -> B&W 803D Ben Diss's Profile: http://forums.slimdevices.com/member.php?userid=4289 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
mr_bill;164751 Wrote: > Sean, > > As an example, could you explain to us how to best use the jumpers in > the Transporter and the volume range of 0-100 to properly match source > to amp. That would be very helpful. > The new 0 to 100 scale is, I believe, true decibels. (In the past when we used only 40 steps, it was a more complicated curve designed to stretch out the low end of the range). So -10 corresponds to 90, -20 to 80, and -30 to 70. > > If you have an SB3 and Benchmark Dac1, you can use the Benchmark's > internal jumpers to match the source to amp also (I think!!) > Thanks, > Bill Correct - exactly the same concept. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
seanadams;164681 Wrote: > You _ALWAYS_ lose SNR and dynamic range. The "you still have all the > bits" concept is completely flawed. > > You MUST match your source to your amp using analog attenuation. You > can use 1) the gain controls on your amp 2) a preamp or 3) a RCA > in-line attenuator or 4) Transporter's built-in jumpers. > > Use the digital volume for day-to-day adjustment within your normal > listening range, not to compensate for a badly matched system. > > This has been discussed many times here, but I won't refer you to our > archives as there have been far too many people still getting it wrong. > Instead, here's a detailed and correct explanation from Lavry (login > needed): > > http://lavryengineering.com/lavry_forum/login.php?redirect=viewtopic.php&t=76 > > If you don't "believe" the theory (which many people don't for some > reason) here is a simple test which one customer did which gives the > expected results. Note that he is using older software which shows the > volume range as 0-40. In the current software it is 0-100. > > http://mysite.verizon.net/forumwebspace/RightMark/Test%20Reports/Volume.htm Sean, As an example, could you explain to us how to best use the jumpers in the Transporter and the volume range of 0-100 to properly match source to amp. That would be very helpful. If you have an SB3 and Benchmark Dac1, you can use the Benchmark's internal jumpers to match the source to amp also (I think!!) Thanks, Bill -- mr_bill mr_bill's Profile: http://forums.slimdevices.com/member.php?userid=6737 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
So if you send digital output to a dac I assume that you should use fixed digital out of either a SB or Transporter and then adjust volume after entering analog domain, right? How about when using analog out of Trasporter to a preamp. Any general suggestions on where to adjust volume or how to figure the correct ranges on each piece of gear? The link to the Lavry site doesn't seem to work right. I get sent to their general forum start and not to any specific topic. I would like to suggest you should write a FAQ about this whole volume setting as there does seem to be so much conflicting information given. Thanks -- wshields wshields's Profile: http://forums.slimdevices.com/member.php?userid=8639 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Hi Sean. Is the info in that first link too vast to cut & paste here (to save everyone interested in this topic registering)? Where I use squeezeboxes, I have my maximum volume set by pre/integrated amps, and I then use the squeezeboxes to adjust the volume down, and while I expected a reduced SNR, I thought this would be insignificant, as I was reducing the volume at the same time (maybe it's still significant, but I've never noticed it). I can see this would not be the same if you were already lowering the volume on the squeezebox to get to your maximum volume setting, where the reduced SNR would be more noticeable (eg, with the Entech DAC & no preamp). I assume the details of losing dynamic range by digitally reducing the volume is in the link you posted, so I shall go study. -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
Triggaaar;164680 Wrote: > You will be fine, the fact that the external DAC is 20 bit does not > matter. The squeezebox does not use 8 bits for volume information, but > it does start with 24 bits, which is 8 more than were on the CD you > probably started with. You will lose bits when reducing the volume > digitally, and some cleaver chap has worked out that you can digitally > reduce the volume to 40 before reducing your signal below 16 bits. The > fact that your external DAC is 20 bit, and the internal DAC is 24 bit, > does not negatively change the principle. This is completely, 100% wrong. It doesn't matter how many people say this, it is still wrong. -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
You _ALWAYS_ lose SNR and dynamic range. The "you still have all the bits" concept is completely flawed. You MUST match your source to your amp using analog attenuation. You can use 1) the gain controls on your amp 2) a preamp or 3) a RCA in-line attenuator or 4) Transporter's built-in jumpers. Use the digital volume for day-to-day adjustment within your normal listening range, not to compensate for a badly matched system. This has been discussed many times here, but I won't refer you to our archives as there have been far too many people still getting it wrong. Instead, here's a detailed and correct explanation from Lavry (login needed): http://lavryengineering.com/lavry_forum/login.php?redirect=viewtopic.php&t=76 If you don't "believe" the theory (which many people don't for some reason) here is a simple test which one customer did which gives the expected results: http://mysite.verizon.net/forumwebspace/RightMark/Test%20Reports/Volume.htm -- seanadams seanadams's Profile: http://forums.slimdevices.com/member.php?userid=3 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB3 volume control with 20-bit external DAC
You will be fine, the fact that the external DAC is 20 bit does not matter. The squeezebox does not use 8 bits for volume information, but it does start with 24 bits, which is 8 more than were on the CD you probably started with. You will lose bits when reducing the volume digitally, and some cleaver chap has worked out that you can digitally reduce the volume to 40 before reducing your signal below 16 bits. The fact that your external DAC is 20 bit, and the internal DAC is 24 bit, does not negatively change the principle. -- Triggaaar Triggaaar's Profile: http://forums.slimdevices.com/member.php?userid=1417 View this thread: http://forums.slimdevices.com/showthread.php?t=30916 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
