[SlimDevices: Audiophiles] Re: Slight click in FLAC track transitions
I have also voted for this bug and encourage others to vote for it too. -- buddachile ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: 88.2/96khz upsample w/SB2 internal DAC possible?
There is a school of thought that upsampling in software means you can build more accurate digital filters etc... See some discussion at: http://db.audioasylum.com/cgi/m.mpl?forum=pcaudio&n=4690&highlight=secret+rabbit&r=&session= Having played with this foobar upsampler, it can eat most of the CPU cycles on my PC, but does make some 'difference' via the RME sound card in my 2G Athlon PC - [NB I'm not claiming it is better!] Hence the more complex functions aren't realistic for a SB2 type device in software, but could be an option for server side upsampling if the rest of the chain could do 24/96. -- Triode ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Cheers Robin for the simple explanations for a simple brain. Getting the hang of this attenuation business now...!? Actually changed attenuation to 12, as vol no.20 was rather loud and as the bass is a tad flabby at the mo did not want to push it any more - will wait till I get a better analogue cable. : Well, I expect the UI to change - this is something Sean has knocked out quick and there is almost certainly a better way to specify the attenuation. I'm sure he'll come up with something better. Any suggestions?[/color] -- Deaf Cat ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: 88.2/96khz upsample w/SB2 internal DAC possible?
usualsuspects Wrote: > The datasheet for the PCM1748 (DAC used in SB2) is 24bit/96khz. I see > that the 16 to 24bits resampling is being done, but could the SB2 also > be made to do 44.1 to 88.2khz and 48 to 96khz upsampling? Or is it > already doing that? We feed the DAC at 44.1/48. I don't think there is any advantage to upsampling before the DAC, as the DAC does this anyway (8x oversampling for the digital filter). Keep in mind upsampling (aka oversampling) is the same as "digital zoom" in a camera - it doesn't add any new information. The DAC does it internally in order to apply a sharper/better/cheaper filter than can be achieved with analog passives. Would be more interested in 88.2/96KHz support for those native file formats. I haven't yet looked at what all it would take to go to 96KHz - obviously clock rates, data rates, and CPU cycles double all over the place. It's not outside the realm of feasibility though. -- seanadams ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Deaf Cat said the following on 09/09/2005 22:55: Cheers for the explanations, All Clear, except, hope you don't mind another (maybe daft) question: So, take 8.75dBu off of 2.12V to end up with 0.7746V (Which is what my power amp would like-roughly 0.8V-cool) Correct. So, if we add 8.75dBu attenuation (it would be safest to round it to 9dBu I suppose) into the Option Box in the Audio settings for the SB2 we should be fine. 8.5 would probably be OK, or even 8. But how does the 8.75dBu relate to the 0.0 - 63.0dB scale? 0.0 is 0dB attenuation so the output is 8.75dBu. 8.5 is 8.5dB attenuation so the output is 0.25dBu. 63 is 63dB attenuation so the output is -54.25dBu Oh Boy! Takes alot of brain power to almost understand that taking off is addin on and 0 is 0.7, quite intresting how logs relate though. Well, I expect the UI to change - this is something Sean has knocked out quick and there is almost certainly a better way to specify the attenuation. I'm sure he'll come up with something better. Any suggestions? BTW, the firmware has just been relased. I've downloaded it and can report that it's working well. Is this in the 6.2, 2005-09-09 download? No, but it's probably in 2005-09-10. if you're downloading regularly I recommend using svn to get the latest updates. I'm not sure that the way of setting the attenutation is the most intuitive of user interfaces, but it does the job. Your telling me!! Who would have thought it a! Buy a bit of audio equipment and then starting to want to know about Logarithms!! Thanks again for the explanations. Unfortunately, your ears are logarithmic. It's just you didn't know about it before now! How about just a pop-up list with "quiet", "not so quiet", "loud", "eleven"? :) ""eleven"" - FAB. ;) R. -- http://robinbowes.com If a man speaks in a forest, and his wife's not there, is he still wrong? ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: digital output format?
Nicola Fankhauser Wrote: > > > btw, is there an explanation why FLAC files sound so much better than > MP3 on the SB2 (analog output)? I maybe will try how (high quality, if > that exists :) MP3 files sound through my own DAC. > > That would probably be because your FLAC files are lossless - they are converted in the SB2 back into a bitstream which is "identical" to the WAV files you started with. Your MP3s will certainly be lossy - though quite how audible the difference will be depends on the quality of the encoder and the bit rate. There are plenty of people who will say a good MP3 at 320kbits is as good as lossless - but if you're down at 128kbits, say, you'd probably have to be hearing-impaired not to be able to tell. Ceejay -- ceejay ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] 88.2/96khz upsample w/SB2 internal DAC possible?
The datasheet for the PCM1748 (DAC used in SB2) is 24bit/96khz. I see that the 16 to 24bits resampling is being done, but could the SB2 also be made to do 44.1 to 88.2khz and 48 to 96khz upsampling? Or is it already doing that? -- usualsuspects ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Stock Powersupply
Does anyone know the ripple on the stock PSU? If I could DIY one with .25mV ripple would this be an improvement? -- bjackson ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
On Sep 10, 2005, at 9:55 AM, JJZolx wrote: seanadams Wrote: Right now the sofware volume control uses an 8-bit linear value which by itself doesn't give enough levels on the low end of the scale. If volume control is done in the CPU couldn't it have been made nonlinear to address the problem at the lower volumes? Yes, we'll be fixing this. Or would that be difficult/confusing for users? Nope, linear is the one that doesn't make any sense. ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Thank you Robin Bowes. Latest nightly working as expected. -- Music Machine ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
seanadams Wrote: > Eh? They're both digital - just one's done in the CPU and one's done in > the DAC. Eh, brain fart. seanadams Wrote: > Right now the sofware volume control uses an 8-bit linear value which by > itself doesn't give enough levels on the low end of the scale. If volume control is done in the CPU couldn't it have been made nonlinear to address the problem at the lower volumes? Or would that be difficult/confusing for users? -- JJZolx Jim ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
Music Machine said the following on 10/09/2005 17:30: "Preamp Volume Control" not working in my setup. Have updated to nightly SlimServer_v2005-09-09.exe and installed firmware update. SlimServer Version: 6.2b1 - 4218 - Windows 2000 - EN - cp1252 Player Firmware Version: 20 W2K, wired only SB2 Trying a few setting from 0 to 60 in "Preamp Volume Control" made no difference. I'm using SB2 analog outs. I just got SB2 about a week ago and there is no going back to disk players. Would like to connect directly to my power amp so any suggestions that might help me use this feature are greatly appreciated. Preamp Volume is in firmware > 20, i.e. from v21. I got it sooner than the 10/09 nightly because I track svn. R. -- http://robinbowes.com If a man speaks in a forest, and his wife's not there, is he still wrong? ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
"Preamp Volume Control" not working in my setup. Have updated to nightly SlimServer_v2005-09-09.exe and installed firmware update. SlimServer Version: 6.2b1 - 4218 - Windows 2000 - EN - cp1252 Player Firmware Version: 20 W2K, wired only SB2 Trying a few setting from 0 to 60 in "Preamp Volume Control" made no difference. I'm using SB2 analog outs. I just got SB2 about a week ago and there is no going back to disk players. Would like to connect directly to my power amp so any suggestions that might help me use this feature are greatly appreciated. Regards Music Machine -- Music Machine ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
It works lovely, thanks everso for getting this extra enhancement up and running. Started with attenuation of 30 just to be extra safe (knowing it should be 8.75 for my particular power amp-0.8V-thanks very much to Robin for explaining), then 20 and I'm on 10 at the mo and do not think I need to go to the 8.75. Next is to get a decent interconnect to tighten up the bass a bit more and smooth the voices. Thanks again for this enhancement. -- Deaf Cat ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB2: reduce analog out voltage by 10x?
rme Wrote: > Does this change for volume control degrade the quality of the stream? > I saw a prior thread on analog volume reductions dropping bits. > > This sounds like it is changing voltage instead so I have no idea of > whether it's changing the data or is truely like a preamp volume > control. > > Thanks for any insight into this. I don't know how the volume control is implemented in the DAC except that it is a digital function. Here's the data sheet: http://www-s.ti.com/sc/ds/pcm1748.pdf -- seanadams ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: digital output format?
hello sean thanks for helping, it turned out that my DAC was not working properly. I repaired it and it works like a charm with the SB2! first listening tests indicate that in comparison with the SB2 my own DAC reproduces music a bit warmer and "opens the stage" somehow - yet the differences are subtle, difficult to pin-point and I like the sound of the SB2 a lot as well. btw, is there an explanation why FLAC files sound so much better than MP3 on the SB2 (analog output)? I maybe will try how (high quality, if that exists :) MP3 files sound through my own DAC. thanks again! nicola -- Nicola Fankhauser ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
