[SlimDevices: Audiophiles] Re: SB-3 and external DAC
The disadvantage of using asynchronous clocks is that sooner or later you will have a buffer (FIFO) under- or over- run to deal with. Once that happens I don't think you have much alternative other than to either drop or repeat an audio sample. Using Xtals at 30ppm accuracy, you could still have up to 60ppm difference between them, which (if my maths is correct) is about 2.6 samples difference every second (assuming 44.1KHz samples). Surely repeating or dropping up to 2.6 audio samples per second would a) have a negative effect on the performance of an oversampling DAC's filters, and b) be audiable? So whilst the BM may be great on jitter imunity, does it suffer from a more fundamental (but even harder to measure) flaw? -- 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=17948 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB1 digital out compared to SB2 and SB3
SB2 SPDIF output is much better than SB1. -- JayNYC JayNYC's Profile: http://forums.slimdevices.com/member.php?userid=121 View this thread: http://forums.slimdevices.com/showthread.php?t=18116 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
Re: [SlimDevices: Audiophiles] SB1 digital out compared to SB2 and SB3
On Fri, 2005-11-11 at 23:02 -0800, kronos wrote: is there a difference between the DIGITAL out of the SB1 and the DIGITAL out of the SB2 ? ...i'm planning on using an external DAC, so i thank you all in advance for feedback that will help me decide which SQUEEZEBOX i am going to buy. There should be no significant difference between the digital output of a SB1 and the 2/3 models. There is a big difference in the display which I think is important for reading the song info across the room. But with the new models I'm not sure that you even need an external DAC. I'd recommend getting a SB2 or later, and trying it for a while. Then if you are happy, you have saved the money for the DAC. And if you still want the DAC, you haven't lost any serious money -- Pat http://www.pfarrell.com/music/slimserver/slimsoftware.html ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB1 digital out compared to SB2 and SB3
I think this depends on your dac, what it does to reduce jitter and if it is fussy about the frequency of the digital signal. SB1 used an integrated chip to do the dsp functions and produce the spdif output. This had a known limitation that the exact frequency it produced could be slightly off 44.1 KHz and given that the chip vendor was unwilling to fix it, slim had no control over it. This is no cause for concern for the vast majority of dac users, but did impact some as their external dac was unable to lock onto the signal. There were also some reports of channels swapping over in SB1 due to the operation of the dsp chip. The dsp chip in SB1 also used a PLL to derive the clock used for the digital out. This means that the jitter on this clock is higher than that which would be obtained with a direct crystal based oscillator. SB2/3 should have all of this solved - the spdif output is generated directly from a crystal oscillator with no PLL. There are two separate crystals for 44.1 and 48 KHz sampling. So what does this mean, I would suggest: 1) If you dac is not fussy about the exact frequency of the digital input (does not experience 'lock' problems) and has internal circitry to reduce jitter, then you may not hear any benefit from SB2/3. 2) If however your dac is fussy about locking or does not have strong jitter rejection, then the SB2/3 is likely give better performance. The one hardware change between SB3 and SB2 will also be beneficial as it should further reduce the jitter on the digital output. In short SB3 (and 2) is definately technically better for the digital output than SB1. Whether you can hear this depends on how well your external dac hides the influence of jitter from the transport. -- Triode Triode's Profile: http://forums.slimdevices.com/member.php?userid=17 View this thread: http://forums.slimdevices.com/showthread.php?t=18116 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: modded to death?
Triode Wrote: Is the xilinx definately receiving a clock? What's the waverform of the spdif look like? If you try to play something which uses the other clock input (48KHz sampled) does this do the same thing? [Assuming you've not removed/modded this too!] Yes it's receiving the clock, input wave is ok, but there's no spdif output wave at all. I've removed the other clock, I'll have to rebuild an oscillator to try it... I guess it's dead, but I think it's worth to buy a new one. I'll buy two this time, so I can compare various modications. -- void void's Profile: http://forums.slimdevices.com/member.php?userid=1380 View this thread: http://forums.slimdevices.com/showthread.php?t=18106 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Import method in Itunes for best possible sound quality?
Though I don't understand why they had to create apple lossless when there are so many lossless compression alternatives. My guess is they want to tie you to itunes. Here is a nice write up on lossless compression http://mp3.radified.com/lossless.htm I don't use apple lossless because it only works in windows and I prefer linux. Honestly, storage space is so cheap I decided not to fuck around and just bought a healthy NAS and ripped big ol' uncompressed wav files using Exact Audio Copy http://www.exactaudiocopy.de/ -- simonrene simonrene's Profile: http://forums.slimdevices.com/member.php?userid=2268 View this thread: http://forums.slimdevices.com/showthread.php?t=17672 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB-3 and external DAC
Patrick, you are right that this would be a serious problem, but it is taken care of by the AD1896: http://www.analog.com/en/prod/0,,765_807_AD1896%2C00.html This chip performs the 'upsampling' and continuously adjusts the multiplier it uses to compensate for any drift between the external and internal clocks. -- bludragon bludragon's Profile: http://forums.slimdevices.com/member.php?userid=1530 View this thread: http://forums.slimdevices.com/showthread.php?t=17948 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB-3 and external DAC
Thanks for that, I'll have to look at it more closely, but I can't quite believe that wouldn't do something fairly horrible to the audio! -- 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=17948 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: SB1 digital out compared to SB2 and SB3
THANKS a lot guys, now i'm out there looking for info about frequency of digital input and internal circuitry to reduce jitter for my soon to be delivered : Triode Wrote: DAC-AH Dac special DIYCLUB version (Red PCB) using CS8414 as digital input reciver, 8 pcs of TDA1543 in parallel (matched). EL2044 OPAMP, On board with three seperate rectifier and regulators provide power to digital and analog circuit. Optical and Coaxial input selectable (Ready plug in and play) available for 135$ + shipping here : http://tinyurl.com/cfnrc Not being a techie i don't really understand if the answer to my question is already included in the DAC elements description... =P anyway, if you are interested too just click on the link; if you have one and feel like dropping a line, it will certainly help me decide whether to go SB1 or later. Triode Wrote: 1) If you dac is not fussy about the exact frequency of the digital input (does not experience 'lock' problems) and has internal circitry to reduce jitter, then you may not hear any benefit from SB2/3. THANKS ! -- kronos kronos's Profile: http://forums.slimdevices.com/member.php?userid=728 View this thread: http://forums.slimdevices.com/showthread.php?t=18116 ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
