Fortunately or unfortunately (depending on one's point of view), there's only one product that will meet my DAC preferences. These preferences are:
1) >/= 2 optical "toslink" inputs
2) HDMI for SACD playback from external transport
3) native DSD processing with no DoP transport layer
4) decent warranty from an established stable company
5) home audition period with "no questions" return policy
6) direct access to technical staff
The only product that I have been able to find so far is the DAC included in the Bryston BR-20 streaming preamp.
(The Bryston BDA-3 DAC, although much less expensive, has HDMI inputs but has only one optical input.)
The solution to my requirements does not come cheap, unfortunately. My feature preferences aside, I have had disappointing experiences with cheap commodity products (e.g. Topping D90 DAC), and I just don't care to expose myself to any more frustration with disposable non-repairable products from non-responsive or inaccessible companies. I like products that function reliably, and I like dealing with companies with available articulate technical support that make sure the product functions reliably, and I like getting exactly what I want (who doesn't?). If I go for the BR-20, it will be the first Bryston product that I have ever owned, and it will be integrated into my system, some of the components of which are 30 years old. A wise person once advised me that buying "the best" usually ends up being an economical option in the long run. The BR-20 could be the last preamp/DAC that I ever buy, if I buy it. I have yet to audition one. But it shouldn't sound any worse than any DAC I've heard so far, right?
Why no DoP? My only experience with DoP was with an Hegel integrated amp that I had for a few days a few years back, which I returned. When using the DAC, there was an audible pop in DSD playback under some conditions that could not be ignored. I reviewed the formal DoP specification, which included a warning of this phenomenon for potential developers, but which Hegel evidently overlooked. If you're interested, you can read that story here:
Short Version: It appears that the DAC in my new H390 may not correctly implement preventative recommendations on page 2 of the DoP standard, resulting in an audible, and not inconsequential, "POP" sound when starting and stopping DSD64 and DSD128 playback. DSD256 playback is just fine. But the...
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