Is DEQX a game changer?

How would you add a better DAC to a DEQX preamp?  If it comes before the DEQX and goes into the analogue input, isn't the superior DAC's signal then reduced to the limits of the DEQX's DAC?  I read that you can use a superior DAC after the DEQX on the output side, but if you are using the crossover function (I would be) then you have the better DAC between the DEQX and the high frequency amp, but the DEQX DAC direct to the low frequency amp.  This does not seem right to me.  

This consideration is even greater if MQA rises to ubiquity.  Do you decode the MQA file in a DAC before the DEQX, then what happens to the decoded MQA signal when it goes through the new A/D and D/A processing in the DEQX?  Is the higher resolution preserved?  

I am using an external DAC which processes CD and FLAC files via the balanced analogue inputs on the HDP-5. The DEQX DAC is excellent but my preference is for something which is almost indistinguishable from other analogue sources - without any sense of digital glare which is present in every other DAC I have experienced.

In my system, the HDP-5 RCA analogue input takes the main turntable & the balanced XLR analogue input has the external DAC which also has a pass through for a second turntable & an SACD player. I do not use any of the digital inputs.

Hi Andrew,

I’m not sure I understand the first paragraph of your post just above. If you are using an external DAC via the HDP-5’s balanced analog inputs, aren’t you then still using the HDP-5’s built-in DAC as well, and also inserting the HDP-5’s A/D converter function into the signal path?

Thanks.  Best regards,
-- Al

Yes, that's what I was wondering too.  Wouldn't the signal be limited to the weakest link in the chain?  Would the analogue output of the superior DAC not be limited to the same quality as if the original digital signal was just sent through the DEQX directly?

Jeff, yes, all of the questions you raised in your previous post seem to me to be logical and valid concerns. Although as you’ve probably seen earlier in the thread many DEQX users having very high quality systems consider the DAC function and the overall transparency of their units to be excellent.

Also, while I’m not in a position to comment on how the sonic quality of the HDP-5’s D/A converter compares to the sonic quality of its A/D converter, as an electrical engineer who has designed several A/D and D/A circuits over the years (for defense electronics), I can say that generally speaking it is a considerably greater challenge to design a good performing A/D circuit than a comparably good D/A circuit, assuming both are required to perform at similar sample rates and resolutions/bit depths.

So I wouldn’t be surprised if keeping a DEQX’s A/D converter out of the signal path would have the potential to provide greater benefit than keeping its D/A converter out of the signal path. Although, again, I’ve personally been very pleased with the transparency and overall performance of my HDP-5 with both in the signal path.

Best regards,
-- Al