Yes I'm using the standard 28V supply at the moment, I did briefly (for convenience) run it off the V200's 24V supply and didn't notice any obvious difference between them in that very brief listening session. From memory I think the STM recommendations are 24V for 4 Ohm speakers and 32V for 8 Ohm - so 28V might well be a sweet spot for the typical 8 Ohm speakers dropping to 6 Ohms or so in places.
I use the audio chromecast as an optical cable source and is similar to usb, it's fine, I read that the D8 needs 32v, but how many ampers should it have for not going to clipping?
Nope. 32v is the maximum voltage for this amp, it is fine with the supplied 28v power supply it comes with and as I have said also OK at 24v. Power-wise 32V is perhaps going to be optimal for 8 Ohm speakers and 24V for 4 Ohm.
If looking for something better than the standard supply I'd aim for amps in excess of 150/your_chosen_voltage
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The only difference I had to do is connect a shielded power cord with the socket attached to the ground just to the wall outlet.
Well, in my case with Alientek D8 and its XMOS it is not so OK, because sometimes XMOS driver in Windows has trouble with its data buffer being empty which causes the amplifier to mute itself. And then I have to unmute it manually. This happens rarely and unpredictably, but it does happen.
has anyone tried those FDA with smps? I heard Sure amplifiers with Meanwell HLG power supply and it sounded VERY good.
Besides that has anyone tried those FDA with smps? I heard Sure amplifiers with Meanwell HLG power supply and it sounded VERY good.
Besides that
IS the Alientek still safest choice of those FDA amps?
So as a sumary we have
cheap FDAs (d802, d8, v200 ... )
more expensive QULOOS QA690 which doesnt sound better than the one above
similar price Wadia 151
and much more expensive
Nad m32 & Lyngdorf TDAI-2710
Has anyone had a chance to hear those very expensive FDA and can really say that difference in price comes along with its SQ?
Thx
Besides that has anyone tried those FDA with smps? I heard Sure amplifiers with Meanwell HLG power supply and it sounded VERY good.
Besides that
IS the Alientek still safest choice of those FDA amps?
So as a sumary we have
cheap FDAs (d802, d8, v200 ... )
more expensive QULOOS QA690 which doesnt sound better than the one above
similar price Wadia 151
and much more expensive
Nad m32 & Lyngdorf TDAI-2710
Has anyone had a chance to hear those very expensive FDA and can really say that difference in price comes along with its SQ?
Thx
@mixMZ :
I did an headphone amp with the 333BW chip on a board (see my post #262 in DIYaudio here : Full digital amplifier with chip STA326)
I've the 802, the YJHiFi, the topping and the NAD M51... All these units are amazing and are better than several "classical" DACs even with the best Sabre chips.
For the price and considering that all the ST326 based FDAs, do all the job, i. e. converting and amplifying the audio signals, I think they all deserve a listening.
I did an headphone amp with the 333BW chip on a board (see my post #262 in DIYaudio here : Full digital amplifier with chip STA326)
I've the 802, the YJHiFi, the topping and the NAD M51... All these units are amazing and are better than several "classical" DACs even with the best Sabre chips.
For the price and considering that all the ST326 based FDAs, do all the job, i. e. converting and amplifying the audio signals, I think they all deserve a listening.
Same observations here comparing the SMSL Q5 Pro (TI) and the Alientek D8 (STM). I prefer the D8 overall. The Q5 Pro sounded really good on quiet classical music, with delicate mids. But it compressed a bit with busier music. It was not crisp enough on voices in movies either.
I tried both with full range drivers of either 4ohm or 8ohm (Pluvia 7) running from the same PSU (24v linear to an Allo capacitor multiplier). Both amps improved with the Cap Multiplier, more so than my tpa3118 amp.
The Xmos input on the D8 is not all that special imo, a bit tiring to listen to. I prefer the coax in via my trusty Ebay CM6331A USB board.
I am still curious to hear some of the other FDA amps, though the SMSL AD18 looks to be identical to the Q5 Pro (same chips). I noticed there is a new I.AM.D DAV130 with tas5548 / sta516B and CM6631a/cs8416 on aliexpress, that one could be interesting.
Gwing : do you know what the SPD pin is about?
I suspect it is why my i2s connection is not working with MCLK, SCLK, LRCK and SDIN alone.
I suspect it is why my i2s connection is not working with MCLK, SCLK, LRCK and SDIN alone.
Well, it hasn't reached home yet or been plugged in for listening but I have taken it apart to have a look and it is interesting
Construction-wise it's very neat and tidy.
The Xmos USB board is easily detachable and connected to the main board on one side by four USB pins, labelled on both boards. On the other side of the Xmos board are nine pins, however the main board socket only connects six of these. We have a potentially easy direct 12s entry point for this amp using that socket!
As the mainboard socket does not have those pins labelled (although the xmos board does) I'll enumerate them here for anyone purchasing the cheaper non-xmos version of the amp. Starting from 'P4' label (closest edge of socket to RCA connectors)
1) GND
2) SPD
3) MCLK
4) SCLK
5) SDIN
6) LRCLK
then missing connections for these on the Xmos board
7) RST (I think, first letter hard to read)
8) GND (first letter hard too read)
9) STA
With the xmos board removed there is Pulse PE65612NL transformer revealed labelled USB_SPDIF on the main board. Hopefully this means that both the USB and coax/spdif inputs are isolated, I couldn't visually trace the lines to establish this but its physical positioning on the board would fit such usage.
I would surmise, if I may interject here, that SDIN is "IN" from the XMOS board's point of view and the latter does not transmit anything to the host controller there. If that's the case, then sure, the SPD line sounds like the best candidate for an XMOS board's output bitstream. So, I would try to feed something to the host using SPD(data?)+SCLK(bit clock?)+LRCLK(word clock?) lines synced to the MCLK(master clock?) line and see how it goes. Can you trace where SDIN goes on the main board? I would hope that it can be used to feed audio back to XMOS and on to PC, but I suspect this might require at least a separate word clock line if bidirectional operation of XMOS is to be sustained. Maybe "STA" is precisely that line although it sounds more like "standby".
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Let me rain on your parade here just a little. The easiest way to catch D8's background noise is to set its input to AUX without feeding anything there and turn volume all the way down to 01. Of course, the ADC at the AUX input adds some noise of its own, but at this volume level it is negligible at the speakers. But apparently it is high enough for STA326 to never short its output, which it normally does when it sees zeroes at its digital input. Try to turn volume to 01 then to 00 and then back to 01 again -- you will clearly hear hiss popping on and off between 01 and 00 volume.
You can get the same result with some quiet music turned down to near zero volume on the PC and then fed to D8 via USB or SPDIF. And you can achieve the same (or worse -- I'm not sure about that) nastiness of hiss with D802 in similar circumstances.
thanks for that suggestion. it didn't work straight off with my DIYINHK board but spurred me on to experiment with the pins patched over to the D8 xmos board.
I removed wires one at a time and ended up with .... two wires remaining connected and stereo music coming out!
stranger still - the two wires were SPD and GND (as written on the board) !
how can i2s possibly work without SCLK and LRCLK ?
but perhaps the labelling is not accurate....
I tried some combinations of those two input wires from DATA and MCK/BCK/LRCK on the DIYINHK board but the D8 didn't come to life (the DIYINHK VU meter was active).
I removed wires one at a time and ended up with .... two wires remaining connected and stereo music coming out!
stranger still - the two wires were SPD and GND (as written on the board) !
how can i2s possibly work without SCLK and LRCLK ?
but perhaps the labelling is not accurate....
I tried some combinations of those two input wires from DATA and MCK/BCK/LRCK on the DIYINHK board but the D8 didn't come to life (the DIYINHK VU meter was active).
Music coming out of both speakers AND headphones? They are driven by different I2S receivers (STA326 and a DAC followed by a headphone amp respectively). STA326 is supposed to mute itself if something goes wrong on the I2S side. And, regardless of labeling, two lines are clearly not enough to carry I2S data, unless SPD goes through the host controller and it can magically restore bit and word clocks out of it and pass them on. Weird.
It's quite easy to check with a multimeter whether GND is indeed signal ground, but I doubt if it is anything else.
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Oh, by the way, if XMOS in this I2S interaction is slaved to the host controller (which most probably is the case), then both SCLK and LRCLK are generated by the host (or maybe by some other master) and fed to both XMOS and those receivers. In that case all XMOS has to do is sync its SPD bit stream to those clocks. Probably this synchronization was somehow not lost when you removed those wires, hence all that jazz (or whatever you were listening to).
the xmos daughter board perhaps is off-the-shelf and not made by Alientek themselves (though it is printed Alientek XMOS-V1.6) and there are both SPDIF _and_ I2S outputs.
There certainly are both on the DIYINHK board (though it has a different xmos chip).
SPD ~= SPDIF ?
I think I will test that right now
There certainly are both on the DIYINHK board (though it has a different xmos chip).
SPD ~= SPDIF ?
I think I will test that right now
it's SPDIF alright - I 've hooked up the DIYINHK board through it's SPDIF output and it plays.
so that quashes my plan to have four of these amps hanging off the DIYINHK board as it only has one SPDIF.
I don't know for sure but it seems likely the D8 uses _only_ the SPDIF output from it's xmos board.
which begs the question whether it will be of inferior SQ to the I2S interface given the PLL (?) recovery of timing from the SPDIF signal.
seems a missed opportunity not to have used clock signal lines directly off the xmos.
Damn! the search for an I2S connectable amp goes on....
so that quashes my plan to have four of these amps hanging off the DIYINHK board as it only has one SPDIF.
I don't know for sure but it seems likely the D8 uses _only_ the SPDIF output from it's xmos board.
which begs the question whether it will be of inferior SQ to the I2S interface given the PLL (?) recovery of timing from the SPDIF signal.
seems a missed opportunity not to have used clock signal lines directly off the xmos.
Damn! the search for an I2S connectable amp goes on....
This seems plausible and in that case SPD most probably goes directly to WM8805 which has 8 (eight!) S/PDIF inputs and some internal jitter correction. Now I wonder if ALL inputs of D8 go through WM8805, although the ADC on AUX does not seem to be capable of S/PDIF output. Anyway WM8805 seems to be the chip generating master clock there.
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