[SlimDevices: Audiophiles] Re: Re-boxing SB2
I think the SB2 would be worth your attentions, mine is sounding bloody marvellous at present, to the point I now feel it's little different, and possibly slightly better, than my main CD player (which cost a 4-figure sum)! Having heard Patrick's last week, with super-reg's installed it sounded amazingly good. This is all still without actually using any of my super-reg's (yet) in mine as I need to do a re-box to allow this, I do have one used as an external linear supply replacing the standard wall-wart though. The things I've done to mine, in some approximation of sonic importance are: - 1) Added a linear regulator (3-terminal at present) to the 'HCU04 (currently fed from the internal 14V) 2) Disabled the 12MHz clock and the SPDIF from the 'HCU04 3) Routed the clock directly to the DAC 4) Added an external linear supply (5V) 5) Changed the analogue decoupling electrolytics for polyester film caps (with 0.5R in series) 6) Changed the output op-amp for an AD8066 7) Re-jigged the o/p stage to be a 2-pole Bessel filter and using polystyrene caps in place of the ceramics 8) Changed the coupling electrolytics between DAC and op-amp and op-amp o/p for Elna Silmics 9) Changed the op-amp bias voltage decoupling for a film cap 1-4 are by far the biggest winners in my view, and I'm certain there are large gains to be had from much better reg's all around, my intention being to replace all the analogue supplies with super-reg's (14V, 5V, 3.3V) once I get the box drilled and ready to receive the SB2! I'll then examine whether the internal switchers cause any problems, now they are isolated from the critical analogue /clock functions. Andy. -- Andrew L. Weekes ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Actual jitter measurements!
These were in fact taken at the DAC input, except the last one which was taken at the hcu04. I was tired when I read your post - now it's obvious, sorry! Interesting then, it seems there's around 10ps or so added by the circuitry / traces between the clock and the DAC, which is pretty good, but explains the audible benefit of the direct feed I've now implemented, which has made this little unassuming box sound rather marvellous and very engaging! It might be interesting too to try a linear reg dedicated to the 'U04, in order to see the benefits of that, which I would expect to be clearly resolvable, although one does need to implement it with care to optimise results*. Great stuff, thanks for sharing it! Andy. * re-reading it looks as if you may have tried this - the pk-pk change is probably simply down to the spectra of the PSU noise, with the skirts being affected more than the main distribution of jitter? -- Andrew L. Weekes ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Re-boxing SB2
Andrew, Any views on the noise spectrum of Nicads/NMHi batteries? I am speculating about a battery psu for the HCU04. As I am only interested in digital out I am wondering whether this is a way to go. I'm Currently using a simple linear reg for this. Adrian -- Triode ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Re-boxing SB2
Triode Wrote: Andrew, Any views on the noise spectrum of Nicads/NMHi batteries? I am speculating about a battery psu for the HCU04. As I am only interested in digital out I am wondering whether this is a way to go. I'm Currently using a simple linear reg for this. Adrian You should get in touch with Vinnie at Red Wine Audio, SB2 battery mods are his specialty. http://www.redwineaudio.com/SB2_Mods.html y. -- Yannzola ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
[SlimDevices: Audiophiles] Re: Re-boxing SB2
Sean - any chance you could confirm the family of the Xilinx chip. I just want to check it doesn't have any problems with input voltages above 3.3V (should be fine if interfaces to 5V or 3.3 V logic which I think it does based on the datasheets I've looked at) The thing I want to try is is 3x 1.2V cells to the HCU04 -- Triode ___ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
