Opinions on AD1955

[MorfiusX]

I've been looking at build a decent DAC, but I am still a newbie to DIY electronics. I found this on eBay (based on an AD1955):

Finished DIR9001 AD1955 (MK3A) DAC &Transformer in Case | eBay

This is in my price range, and given my capability, a decent start to DIY. Anyone have any opinions on the setup?

[Ken Newton]

Judging only from the photos and description (a schematic is necessary to really assess) , this appears to be decent design, and a decent value given the price for what is an assembled product with case and power supply.

The AD1955 is Analog Devices' current top-of-line DAC chip - although many of their own high-end customers seem to disagree about that. I'm not a fan of the DIR9001 digital input reciever. I do see liberal use of what appear to be film type capacitors, which is a good thing. While the analog stage op-amps aren't listed, it appears the vendor had the foresight to mount them in sockets so to facilitate op-amp "rolling". If you choose to purchase this DAC, I would suspect that you will be able to improve the sound simply by experimenting with different op-amps.

Having said all of that, the only things which truly matter, IMO, regarding the purchase of HiFi equipment are how it sounds, what it costs, how reliable it will be, and how much of your purchase price it will retain when it inevitably comes time to sell it for something better. You might not be able to expect much from those last two points with this product, but without hearing it first, you are gambling on that first and most important point. Although, admittedly, it would only be a $140 gamble.

[MorfiusX]

Here's a little better view of the board:

http://i.ebayimg.com/00/$%28KGrHqYOK...Sw%7E%7E_3.JPG

[210]

The AD1954 (stereo version of the 1955) sounds pseudo detailed but grainy in my Kenwood-DPF3030 CDP (even modded) conpared to my external PCM1702 (DA500) and PCM1793-DAC's which I prefer. Maybe just a tendency and implement depending.

[pieter t]

Originally Posted by 210

The AD1954 (stereo version of the 1955) sounds pseudo detailed but grainy in my Kenwood-DPF3030 CDP (even modded) conpared to my external PCM1702 (DA500) and PCM1793-DAC's which I prefer. Maybe just a tendency and implement depending.

Check datasheets please.
AD1954 is a three-channel DSP with built in DACs, for example for a stereo + subwoofer application.
AD1955 is a stereo DAC.

[210]

@pieter t: You know you're right.
7dB less SNR and remarkable 13dB more THD
of the AD1855 maybe produce the slightly grainy sound
(apart from upsampling, output-op's, implementation etc.)
out of my CDP compared to CDP's/DAC's with AD1955.

[Alexium]

I wonder if correctly cooked 1955 is better/worse than correctly cooked PCM1794.

[abraxalito]

I have had some very similar (perhaps identical) boards from Taobao (take a look at my blog). The layout sucks so its a great way to learn about how to get decent sound by re-jigging the power supplies and grounding. In the end though the AD1955 doesn't cut it for me any longer sound quality-wise.

[Calvin]

Hi,

after my experience the DAC-Chip itself is not the most important source of a certain ´sonic fingerprint´. The digital filters, Jitter-performance and analogue stages are more discriminating against the sonic performance.
With the surrounding circuitry being equal or very similar the differences between the AD1955 and the PCM179x series are negligible and it´d need a helluva good system to evaluate any differences at all. Simple digital filters and OPamps in the analogue output stages surely degrade the sound quality of most DACs to a lower average.

jauu
Calvin

[Alexium]

Calvin, thanks for the info. I'm just starting to explore DACs. Somehow I thought DAC chip is equally as important as other DAC stages.