I read all 10 pages of comments and what I gather is the DAC of the miniDSP 2x4HD is subjectively and/or objectively not great. That set aside, if one wants to use it only for integrating 2 subwoofers with an AVR, is it still considered not great? I am talking taking the AVR pre-out into the miniDSP, then connecting the two subwoofers so you can do manual time alignment, delays, EQ from REW. So the AVR will see the subs as 1 and you may or may not decide to apply Audyssey.
Is there an alternative or a better product that can do that job ideally compatible with REW EQ filters?
Hmm. If you measure it as Armin did it does not perform as well as some better DACs, primarily because it introduces some noise that can be observed with test equipment. However this noise is at very low levels as someone else said "Whether any noise or jitter or harmonics which are 100 db down are at all audible, is highly debatable. "
I have the version of this running Dirac (MiniDSP DDRC-24). Same hardware but with Dirac software upgrade. Even at very uncomfortably high noise levels I can not hear any noise. I have a 200W amplifier in a moderately large room and do crank it up from time to time. My system is amongst the best I have heard. 100dB down noise is of no issue to me....I can't hear it.
At first I just bought it to play and learn about DSP.....but I became gob smacked with what it can do....and how simply and well it does it.
I was using a Mission DAC playing into an Accoustic Research valve amp. After owning auditioning may DAC and preamp components, I settled on these two items as I liked the character of sound they produced with the rest of my system. I found the system was tailored well to my preferred music genre tastes but the character of sound was not well suited to other genres. Before buying the MinDSP unit I had purchased another DAC E30 DAC to try. (Both it and the Mission are now for sale).
I was also using the crossover built into my SVS sub woofer.
I now use the MiniDSP DRC-24 as my DAC, preamp and room correction system and I also use the parametric equalier function. (More on this in a moment).
Here's what I like.
1. Dirac frequency response and phase response room/speaker correction provides a stunning improvement in sound quality worth many times more than the downside of noise ......100dB down that I can't hear. (Get over noise you can measure and are unlikely to hear)
2. Dirac sounds much better than just REW frequency response correction which I have experimented with (and liked) on the past in my system.
3. I suspect Dirac sounds just as good as REW + Phase correction software, but I haven't played with using phase correction with REW. But much easier to set up and I can save different presets I can select from the MinDSP remote.
4. The MiniDSP parammetric qualiser function is a bonus. I have further tailored remote selectable presets to suit my preferences for different genres of music (no longer stuck with one sound characteristic).
5. The very MiniDSP's very flexible crossover is a bonus. I have disabled the crossover in my high end sub woofer and now use the crossover in the MiniDSP. I can select from a variety of different types of crossover and different cross over slopes and I cancontrol both when the woofers in my main speakers roll off (couldn't do this before) and when the sub woofer starts doing it's thing. Integrating a single woofer is simple and effective.
6. I still use my passive room correction (bass traps) as well. Dirac provides very noticeabl icing on top of a already reasonable room acoustics.
The result? This cheap unit has replaced my expensive DAC and Preamp. I am no longer interested in audtioning more DACs or preamps to explore different characters of sound. My sound is now very tailorable. I don't have to chose between a DAC with this sound or a DAC with that sound. I can have either at the push of a button on the remote. For the firt time I can tailor/personalise the sound to my own preferences. I have come to the realisation that DSP is the future of high end audio.
If MiniDSP or anyone else comes up with a DSP system that has similar functionality and can improve the sound further I will buy it. But at the moment I am enjoying the best sound I have ever heard from the rest of my system.
Please don't get distracted by issues you probably won't hear, that will stop you taking advantage of sonic improvements that could be stunning.