There is a thread about native DSD DACs. However, if I want to play PCM and NOT have any transforms through out the playback path, what are the best NOS (I would assume) DACs for HQPlayer and PCM.
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The best measuring NOS PCM dac would be the Holo May KTE dac. In my opinion the May sounds excellent in PCM, even better than DSD. Timbre and dynamics is better in PCM, and DSD is softer and easier.
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I think Holo Spring 2, Spring 3 or May are among the best in this respect. You get both PCM and DSD sides included, but you can of course choose which one you wish to use.
There may be a few suitable PCM1704 based devices out there, but these are rather rare. And few R2Râs I have not yet tested, but would like to (Soekris).
I bet some vintage R2R chips may be good budget option, e.g. NOS AD1865
Iâve been looking at these vintage chips recently.
Philipsâ TDA1541, 1543, 1305 (not sure if it is R2R), 1387 (R2R?)
BBâs PCM1704, PCM1794 (hybrid model)
ADâs 1862, 1865, 1868
I noticed there are quite a lot of people are making these now and selling them in ebay / AliExpress
One of the interesting ones is a model based on 47Labâs design (a japanese boutique shop). The original one model 4715 based on TDA1543 was selling more than $1200. Itâs design is very simple and there are similar ones selling for less than $20.
However, most of these vintage chip only support 44.1/48k/16 bit. Some can go up to 20bit or 24bit. With a good USB frontend, some may go all the way up 192, 384, or even 768k.
PCM1794/PCM1792 is just like the other TI/BB chips ever since transitioning away from R2R, PCM1704 was the last R2R one. So it is practically SDM DAC.
TDA1541A and other such are a bit too old 16-bit models designed for 4x (176.4k) oversampled use through the SAA7220 digital filter. These just cannot reach todayâs standards. TDA1543 is the cheap economy model of TDA1541A.
TDA1305 is a DSD-DAC, from itâs built-in digital filter and modulator. You recognize these from the âBitstream Conversionâ logo (DSD). The digital filter converts to 705.6/768k rate followed by the usual S/H (sample copy) 6x oversampling and then followed by a very simple 2nd order modulator and then feeding a 16-element DSD DAC. TDA1387 is a plain 32 element âDSD Directâ DAC chip without digital filter or modulator.
Those AD186x chips are R2R chips, similar to PCM1700 and such dual chips.
P.S. Note that these vintage chips are widely pirated, so be very careful buying anything these days that claims to have such. Most of the time those chips available on the market are something totally different inside than the printing on the top would let one assume.
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Iâm glad you started this but I doubt it will draw as much interest as DSD upsampling which is de rigueur. I have the Holo May KTE and listen mostly with PCM, closed-form-m . I do sometimes listen to DSD and enjoy it as well, usually with plain old poly-sinc-lp
I think PCM1794 is so-called hybrid chip. Not 100% SDM DAC. Correct?
I saw someone can push it to NOS 768k. (For AD1865, I saw they can do NOS 384k).
I saw people are âstackingâ these. 8 chips, 16chips, or even more. Interesting.
They use the same architecture for all recent ones. Like the DSD1793 used by iFi.
Many DACs using these TI/BB chips offer âNOSâ. But it not really a NOS since apart from 6 MSBs at 352.8/384k rate, rest 18 LSBs go through S/H oversampling and their very simple 3rd order modulator:
(this picture doesnât have the 8x PCM digital filter included, which is prior to this one)
So any waveform values below -36 dB of the peak are pure SDM, such as anything near zero-crossing point, or lower level harmonics and high frequencies.
If you run external digital filter mode at 705.6/768k, you can double those rates it can do self-contained.
But best result is to feed the Advanced DWA directly with DSD data in one of itâs four special DSD configurations, bypassing all the prior DSP there.
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Has anyone tried the Lampizator Engine Eleven-based DACs? eg Baltic 4? I suppose the tubes could color the sound a bitâŚ
No, that one is new to me. Not much details on how for example DSD is handled, as it says R2R. So I guess it natively a PCM DAC.
It converts DSD to PCM.
OK, so if the claimed PCM NOS mode works, it could be suitable for PCM use. Iâll have it on my âcurious devicesâ list.
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