Is DEQX a game changer?

FWIW my HDP-5, which has superseded the HDP-4 as DEQX’s top-of-the-line model, uses a switching power supply. I don’t know if it is the same supply that is used in your Mate, but it is an XP Power model ECL30UD02-S. Here is the datasheet for that series of supplies.

I use the HDP-5 as my preamp. I have never sensed that it is causing any glare whatsoever in any part of the spectrum. I am connecting my phono stage (a Herron VTPH-2) to it via unbalanced RCA cables. I am connecting my main digital source (a Bryston BCD-1 CD player used just as a transport) via an AES/EBU digital cable. Those are my two critical sources. I am connecting the HDP-5 to my power amp via unbalanced RCA cables.

I don’t recall what connectivity the Mate provides, but if you are using balanced analog connections to its inputs or outputs perhaps a contributing factor to the issue you described might be an internal balanced/unbalanced converter stage or transformer needed to interface to its presumably unbalanced internal signal path. Or if you are connecting to a digital input, perhaps waveform degradation due to signal reflections resulting from small impedance mismatches is occurring, resulting in jitter that might be improved by changing the length and/or type of the digital cable.

That’s about all I can think of in response to your question.

Good luck. Regards,
-- Al

Since I last posted on here I have added an HDP-5 processor/preamp and as Almarg mentions, this has a low noise switch mode power supply. My HDP-3 uses a linear supply and both sound equally transparent with no top end glare that I can detect. Most of my listening is analogue input from two turntables and my various power amps & subs are also connected via unbalanced RCA cabling.

The HDP-5 has slightly greater clarity and openness to the soundstage than the HDP-3 & I will be using them together in a 4-way stereo setup (0-60hz, 60-200hz, 200-3100hz, 3100khz+), the HDP-3 managing just the subs.

Andrew (Drewan77), congratulations on the new HDP-5!  And thanks once again for the many valuable inputs you have provided to this thread.

Best regards,
-- Al
 

Good info, Kingrex.  Thanks!

BTW, although it undoubtedly has no relevance in the case of your Mate, I'll mention that according to a communication I had with Alan Langford of DEQX last year, incorporation of Larry's mods into a unit that is under factory warranty will invalidate that warranty.

Best of luck as you proceed.  Regards,
-- Al