miniDSP or a USB Audio Interface

[yelloguy]

This is for 2 channel music listening. I currently have a Denon 3600 AVR. I play music using a Windows PC connected via HDMI playing Apple Music lossless. Room EQ is done using the OCA Evo Acoustica. B&W 683 OG speakers. Left one has a SVS PB 1000 Pro sitting next to it (outside) and the right one has a PB1000 (non pro). I can't say that I have any complaints with the sound. 3600 has a DAC that is very well rated by ASR. Music sounds very clear, full, and punchy.

In the spirit of learning and experimentation, I tried connecting the PC's sound card output using RCA cables to the AVR's analog input. I turned off Audyssey. I also connected the sub/center output from the sound card to one subwoofer via RCA. I then used Equalizer APO to set up channel copying, a basic crossover, etc. By doing this I was able to get the left sub to play with my two fronts bypassing my other setup. It sounds a bit muddier, and the sound stage is a bit collapsed or compressed. I am assuming that is because of the better DAC in my Denon. But I am intrigued by this setup and want to do more. Specifically I would like to be able to address and EQ four separate channels from the two incoming channels and feed these to the two fronts and two independent subs.

Would it be better for me to get a miniDSP 2x4 or should I be looking at a USB Audio Interface like Motu or Focusrite? Are there any pros and cons of each approach? What should I look for to get good sound quality? Finally, for those who have done it before, is this going to a futile exercise and I should not expect to beat the sound I am getting from the AVR? I can also get a separate amp for the fronts if there is improvements expected there

Thanks in advance.

 

[kemmler3D]

. It sounds a bit muddier, and the sound stage is a bit collapsed or compressed. I am assuming that is because of the better DAC in my Denon.

Unless you copied the exact settings from Audyssey to EQAPO, I'd bet good money the change in sound is from turning off Audyssey, not the DAC.

Would it be better for me to get a miniDSP 2x4 or should I be looking at a USB Audio Interface like Motu or Focusrite? Are there any pros and cons of each approach?

Mostly depends on how you want to do the DSP. The minidsp will do it onboard, if you go with an interface it will need to be done on the PC. PC offers more flexibility but might be less convenient and trickier to configure.

Finally, for those who have done it before, is this going to a futile exercise and I should not expect to beat the sound I am getting from the AVR?

It won't be easy but you should be able to get some improvements via manual tweaking. BTW you didn't mention if you have a measurement mic, that's a requirement here of course.

I can also get a separate amp for the fronts if there is improvements expected there

Not indicated unless you think you're running short of power.

 

[Keith_W]

Would it be better for me to get a miniDSP 2x4 or should I be looking at a USB Audio Interface like Motu or Focusrite? Are there any pros and cons of each approach? What should I look for to get good sound quality? Finally, for those who have done it before, is this going to a futile exercise and I should not expect to beat the sound I am getting from the AVR? I can also get a separate amp for the fronts if there is improvements expected there

To add to @kemmler3D's comments (which I agree with), here are a few more differences.

- The type of DSP is totally different. Your AVR and MiniDSP use minimum-phase IIR (some models are mixed phase IIR + limited FIR taps). With a PC, you have much more computing power available, so you can use linear-phase FIR. Or minimum-phase FIR, or minimum-phase IIR. You have many more DSP options if you chose an interface + PC. If you don't understand what those terms mean, please read this thread. In short: PC's have virtually unlimited computing power and can run far more sophisticated DSP.

- A MiniDSP is forever locked to what is delivered - you get a certain number of biquads (PEQ's), a certain number of taps, certain number of DAC channels, and a fixed sampling rate. A PC + interface is far more flexible. Everything can be changed.

- MiniDSP's are a far more robust solution than software based DSP. Load the settings into your MiniDSP and that's it, it won't change. Software based solutions are vulnerable to the vagaries of Windows updates, drivers breaking, developer going out of business, and so on.

- MiniDSP's are far superior when it comes to routing audio. You get all the inputs that you need - RCA, XLR analog inputs, optical inputs, etc. Some models have HDMI. An interface may have some of these inputs, and even if you can connect a device to the interface, sending the sound to software is another story. For example, there is no way I am aware of to send input from the ADC on your interface to Roon. With JRiver, you have to open an ASIO listening session every time you want to do this, and it rapidly gets very annoying and it's not user friendly. With MiniDSP, you press a button on your remote, and that's it ... you've switched inputs.

- MiniDSP's are far more convenient. One device + USB microphone + REW and that's it. With an interface + PC, you have to make decisions. If you want a simple solution, it's EqAPO + REW + USB mic and that's it. But if you want linear-phase FIR, you will need one of the paid options like Acourate, Audiolense, Focus Fidelity, and so on. Then you will need a convolver like Hang Loose Convolver. Then you need to figure out how to send music from a music player, streaming service, etc. through the convolver.

Ultimately, you get the potential for better quality with a PC + interface. I say potential because it's not the DSP that matters, it's the user. You have to take the measurements and design the correction, and if you screw it up, you will get bad results no matter what type of DSP you are using. And trust me, you WILL screw it up. All of us have screwed it up. It's normal! If you choose a complex DSP system, the learning curve will be longer.

Those are the differences. One of them might suit your personality a bit more. If you are a "no compromise" kind of guy and willing to put work in to solve all the issues, go with interface + PC. If you are time poor and don't want the hassle, go with the MiniDSP.

 

[yelloguy]

I'd bet good money the change in sound is from turning off Audyssey

Anything is possible. But I have tried turning off Audyssey on the AVR. This is different sound.

you didn't mention if you have a measurement mic, that's a requirement here of course.

I do have a umik-1 and passable familiarity with REW

Not indicated unless you think you're running short of power.

Perfect! That makes sense

@Keith_W that is a super helpful summary. I didn't know some of the points you raised. My heart says Windows and E-APO for flexibility and future proofing, but I am time-poor and I get frustrated easily. Let me read the thread you linked but, my idea was to do bass integration via room EQ and leave the speakers to do what they do best. From where I am right now, even a single sub with those two speakers sounds pretty good. I can probably get away with a halfway decent DAC turning my 2.0 channel music into 2.1 or 2.2. Address a few peaks (and dips) in sub 120 region and call it a day! Maybe time align the speakers and the sub. Sit back and enjoy the music (of course easier said than done! heh)

 

[kemmler3D]

If you are the kind of person where "patience" rather than "interest in tweaking for its own sake" is the limiting factor on setting up your system, I'd go with the MiniDSP. It's still tweak-y but as @Keith_W says, you rule out some problems and complications from the outset.

All that said, compared to Audyssey on your AVR, you are probably chasing a 10-20% improvement in subjective quality, not 50-100%. I'd consider whether that's worth it to you before starting down this path. You said you were happy at the beginning... sometimes "discretion is the better part of valor" in these things.

 

[yelloguy]

discretion is the better part of valor

By discretion you mean getting all discrete components! haha

No seriously, this is helpful. Because on some level I knew this. But seeing it stated like that does bring home the point. If it is really for play, then an interface and Windows is what I need. Because it is not for improving sound by 5-10%

Or I can just leave good enough alone.