You can not change it for now.
Actually the spdif selecting was controlled by the fpga hardware. I can program it having different default just like the *Fs does. The problem is there is no any jumper left on the fifo board
.I recommend using the otp as the default spdif input for a better isolation. With fifo, there is no difference between opt and cox.
Regards,
Ian
Hello,
After about 10 hours burn in and listening Si570 board, replaced TPS7A4700 with TPA v3 Trident modded to 200mA. This noticeably improved IMHO overall sound with naturality, stereo imaging, ambience and midrange quality.
I wonder if the TPS reg needs more time to get better performance, or TPA is just better in this applicartion ?
After about 10 hours burn in and listening Si570 board, replaced TPS7A4700 with TPA v3 Trident modded to 200mA. This noticeably improved IMHO overall sound with naturality, stereo imaging, ambience and midrange quality.
I wonder if the TPS reg needs more time to get better performance, or TPA is just better in this applicartion ?
Hi makumba1966,
Good to know that. You might be the first one besides me experiencing the Si570 clock board.
Si570 clock is very sensitive to PSU. Different PSU sounds quite different in style. Even you change the capacitors. Very interesting.
I have a TPA reg, could you let me know how to mod it to 200mA? I'd like to give a try.
Have you try other power supply? Let me know if you get more discovery.
Regards,
Ian
Hi Ian
To get 200mA CCS form TPA I combined parallel R4 ( 20 Ohm ) with 12 Ohm. I have not tested other regs yet. I tried replace TPS beacuse felt that SI board souds little less natural then xo dual board with CCHD957, but i'm not shure if burn time was enugh to get serious conclusion. Fresh Trident reg does not sound good too to me. Even with TPA, it seems to me, that XO dual board had a little better timbre. But I trust your opinion as well, that Si clock is better too
To get 200mA CCS form TPA I combined parallel R4 ( 20 Ohm ) with 12 Ohm. I have not tested other regs yet. I tried replace TPS beacuse felt that SI board souds little less natural then xo dual board with CCHD957, but i'm not shure if burn time was enugh to get serious conclusion. Fresh Trident reg does not sound good too to me. Even with TPA, it seems to me, that XO dual board had a little better timbre. But I trust your opinion as well, that Si clock is better too
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Hi Ian
To get 200mA CCS form TPA I combined parallel R4 ( 20 Ohm ) with 12 Ohm. I have not tested other regs yet. I tried replace TPS beacuse felt that SI board souds little less natural then xo dual board with CCHD957, but i'm not shure if burn time was enugh to get serious conclusion. Fresh Trident reg does not sound good too to me. Even with TPA, it seems to me, that XO dual board had a little better timbre. But I trust your opinion as well, that Si clock is better too
Thanks makumba1966, I'll try the TPA as the way you did.
At the beginning, on my BIII, I listen to Si570 and dual xo half and half. But now I'm with the Si570 more than dual xo.
I use Cyclon 6V battery as DC input of Si570 clock board, together with the isolator board. My system includes B&W 804, Pass 350.5 and Pass preamp.
If you prefer midrange, you may try the attached 16V MLCCs.
Have fun.
Ian
I never tried battery for clock board, but using isolator board. Have dedicated PS circuits for dac, i/v, fifo and clock board , each include separate trafo + shunt PSU and EMI filters. My system includes Manley Neo Classic monos , big studio monitors based on Focal speakers and some "high end" cables.
This is not a surprise given the noise of trident regulator: 2.9uVrms, 100Kh bandwidth
The output impedance is almost the same as TPS7A4700 regulator.
I suppose no one imagine an integrated regulator will beat a well designed and implemented discrete regulator
Attachments
well its not that far off at 4.17µVrms 100khz bandwidth and whether the trident maintains that same performance at 200mA in reality would be interesting. so I think your scoffing at the idea of an IC being a discrete regulator is a bit unfounded. also 2.9µVrms is hardly world beating as discrete regs go though.
its a nice small discrete reg, but ICs are catching up, certainly its got wider capability in voltage and current
its a nice small discrete reg, but ICs are catching up, certainly its got wider capability in voltage and current
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Not a big surprise for me.
Subjective impressions remain subjective, while technical specs are objective.
Please, compare the phase noise from their datasheet between the CCHD-957 (not more than a standard XO from the shelf) and the Si570. In these datasheets you can find the explanation of your impression.
Typically (not from me, but in most literature from the guru in this matter), higher phase noise decreases the dynamic range, and so our ears feel the sound less natural, mostly in the midrange frequency.
Low Q oscillators with PLL usually perform worst than oscillator with higher Q without any PLL in digital to analog conversion.
I'm not sure if this is the main reason. IMO Si board need several hours more break-in to perform a meaningful comparison. With TPA board it sounds very nice to me, and I do not have any preasure back to CCHD
jeremy loves to beat incessantly on subjective impression forgetting technical specs
we have different point of view, the technical point of view with objective measurement (the old thought school) and the subjective point of view without any demonstration (the new and creative thought school)
Hint of the day: there are thousands of documents on the internet explaining how phase noise, or if you prefere jitter, affects the sound in digital to analog conversion
There is not femto seconds difference from the 2 oscillators: from the Si5770 datasheet -112dBc@100Hz is a BAD performance, also if was measured at 120MHz frequency. Theorically you can subtract 6dB for each division by 2, pratically the phase noise remains the same (you can understand the reason in the thousands of documents on the internet, just read a bit)
we have different point of view, the technical point of view with objective measurement (the old thought school) and the subjective point of view without any demonstration (the new and creative thought school)
Hint of the day: there are thousands of documents on the internet explaining how phase noise, or if you prefere jitter, affects the sound in digital to analog conversion
There is not femto seconds difference from the 2 oscillators: from the Si5770 datasheet -112dBc@100Hz is a BAD performance, also if was measured at 120MHz frequency. Theorically you can subtract 6dB for each division by 2, pratically the phase noise remains the same (you can understand the reason in the thousands of documents on the internet, just read a bit)
subjectively, this has been very interesting. I switched from the Dual Clock board (Isolator, S11 powering DAC & clock board, with TPA inline for dual clock board). to the Si570, TPA powered. Initial impression was slightly less timbre, but more smoothness/analog sounding (something I attributed to the higher clock speeds). Listened for a day and it sounded good; better as the day went on. Switched back this morning to the dual block board (CCHD-957's by the way), and a slight increase in Timbre (missed), but... I think overall the Si570 might be the winner. More listening to come....
Ian - a heartfelt thanks for your time/effort that allows us audio/diy geeks to play on this level. You've allowed me to entertain the absurd pursuit of the minutia.
Ian - a heartfelt thanks for your time/effort that allows us audio/diy geeks to play on this level. You've allowed me to entertain the absurd pursuit of the minutia.
This is not a surprise given the noise of trident regulator: 2.9uVrms, 100Kh bandwidth
The output impedance is almost the same as TPS7A4700 regulator.
I suppose no one imagine an integrated regulator will beat a well designed and implemented discrete regulator
Is that value a measurement or simulation?
subjectively, this has been very interesting. I switched from the Dual Clock board (Isolator, S11 powering DAC & clock board, with TPA inline for dual clock board). to the Si570, TPA powered. Initial impression was slightly less timbre, but more smoothness/analog sounding (something I attributed to the higher clock speeds). Listened for a day and it sounded good; better as the day went on. Switched back this morning to the dual block board (CCHD-957's by the way), and a slight increase in Timbre (missed), but... I think overall the Si570 might be the winner. More listening to come....
Ian - a heartfelt thanks for your time/effort that allows us audio/diy geeks to play on this level. You've allowed me to entertain the absurd pursuit of the minutia.
You welcome MisterRogers. Mine is similar to you.
I have a couple of reg boards for my Si570, even same board with different capacitors, as well as 3.2V battery cell. I always can't decide which one is I want
. That's why I designed a socket for external reg board. Every small change could be heard a this level. Have a nice weekend.
Ian
You welcome MisterRogers. Mine is similar to you.
I have a couple of reg boards for my Si570, even same board with different capacitors, as well as 3.2V battery cell. I always can't decide which one is I want
Have a nice weekend.
Ian
either permutation is so superior to anything our ears have ever heard with regard to jitter performance it just amazes me that you are hearing differences. I mean at this level, jitter should be completely out of the question. Very odd. Makes me think oscillation/intererfance or some other rf phenomenom is occuring.