How to Predict Required MCH DAC Output Voltage

[dped90]

I am total newbie with doing room eq, but I want to pursue learning how to do mic measurements to first do correction using acoustical materials, and to what remaining correction is needed-as much as possible and affordable-using Windows based room correction. But in either case a stereo DAC's no good; I will instead need a MCH DAC for the 2.1 or 3.1 system I'm building, with three Rythmik F12 subs. I was going to look at Amir's list here.

I didn't finish watching the video. But my problem is how do know if given a MCH DAC model-before I buy it-will have sufficient output voltages to compensate for any gain loss from using software based room eq, like REW, DIRAC Live, etc??

 

[staticV3]

my problem is how do know if given a MCH DAC model-before I buy it-will have sufficient output voltages to compensate for any gain loss from using software based room eq, like REW, DIRAC Live, etc??

You mostly don't.

Unless you do your measurements and room correction filter design first, you cannot know how much headroom will be lost.

Therefore, best to buy a DAC with good output voltage (≥4V), for plenty of margin.

 

[dped90]

You mostly don't.

Unless you do your measurements and room correction filter design first, you cannot know how much headroom will be lost.

Therefore, best to buy a DAC with good output voltage (≥4V), for plenty of margin.

Thanks, which leads me to my next question: My new main speakers will be pretty high end-custom built by Troy Crowe and minimum 93db SPL/w/m and very similar to these.
https://josephcrowe.com/products/speaker-system-no-2095 Not certain if a center channel speaker will be added for movie soundtracks.

Though I don't know the sensitivity of his (Revel?) speakers, I recall a one member here (and pretty much everywhere else) who found that using DIRAC Live 3 left him with a 20db gain loss for which his Exasound 8 channel DAC's ~ 4V outputs were powerless to overcome. He ended up having to buy three Topping preamps to compensate. Last I heard he sold those and got a Merging Hapi DAC. https://www.merging.com/products/interfaces/specifications#d-a8-d-a8-p-option-card Later he moved up to the (~ $11K) Merging NADAC MCH DAC.

It looks like that Hapi DAC card gives a choice between maximum dbu output levels which translate either to a ~ 7V or ~ 14V range. https://www.sowter.co.uk/decibels.php
Whether there are better sounding MCH DACs than the Hapi is one concern. But I've also read posts from those at Audiophilestyle, StereoNet and elsewhere saying that the Hapi's numerous interfaces other complexities can be a real nightmare even for room experts.

Perhaps one of these are more newbie friendly? https://motu.com/products/avb/8a/specs.html https://rme-audio.de/adi-8-qs.html

But how might actual sound quality compare among all three?

I don't think my room's too bad: ~ 20 ft x ~ 11 ft, opening into a ~ 13 ft x 9 kitchen. The triangular ceiling over both peaks at 11 ft.

But given all of the above, what kind of (USB based?) mic/ADC set up should I be looking to get for doing my measurements?

And while I'm sure that I can rely on those here for guidance, what's the best Windows based room correction software for total newbies, but not total dummies?

 

[dped90]

Another issue is lossless master volume/mute control. I don't think any of the above MCH DACs have a wireless remote. My player for music DVDs and BDs via my PC's BD drive will usually be JRiver. Apparently, volume/mute control via its interface is lossless. https://yabb.jriver.com/interact/index.php?topic=137785.0

Do you agree? Or is there a better (handheld?) solution?

 

[DVDdoug]

Not certain if a center channel speaker will be added for movie soundtracks.

I'm re-reading Floyd Toole's book, Sound Reproduction* and he says the center speaker is the most important with movies & television.

Another issue is lossless master volume/mute control.

For everyday volume control it's not a problem, and analog volume controls are not "perfect" either... You don't hear the loss of resolution unless you re-amplify, or if you are attenuating and losing resolution at normal-high volumes. And if you have 24-bit audio you can attenuate by -48dB, you still have 16-bits of resolution remaining.


* I'm re-reading it for the purpose of pulling-out and saving some quotes.

 

[Kal Rubinson]

Though I don't know the sensitivity of his (Revel?) speakers, I recall a one member here (and pretty much everywhere else) who found that using DIRAC Live 3 left him with a 20db gain loss for which his Exasound 8 channel DAC's ~ 4V outputs were powerless to overcome. He ended up having to buy three Topping preamps to compensate. Last I heard he sold those and got a Merging Hapi DAC. https://www.merging.com/products/interfaces/specifications#d-a8-d-a8-p-option-card Later he moved up to the (~ $11K) Merging NADAC MCH DAC.

It was I. The big contributor to the problems with loss of gain is the loss of headroom which, in turn, relates to the amplitude of the corrections implemented in DL. This was an extreme case and one I had not run into with earlier corrections. If your prospective speakers have a senstivity of "93db SPL/w/m," it is about 4dB greater than that of the Revels I had at that time. (FWIW, I reviewed the NADAC a long while ago and never purchased one.)

Whether there are better sounding MCH DACs than the Hapi is one concern.

I doubt that.

But I've also read posts from those at Audiophilestyle, StereoNet and elsewhere saying that the Hapi's numerous interfaces other complexities can be a real nightmare even for room experts.

I find that surprising. There is an initial learning period but, once completed, use is clear and logical and, once up and running, operations are stable.

But given all of the above, what kind of (USB based?) mic/ADC set up should I be looking to get for doing my measurements?

USB mic does not require an ADC. I plug the mic directly into any one of the USB ports on the PC that I use with the HAPI.

And while I'm sure that I can rely on those here for guidance, what's the best Windows based room correction software for total newbies, but not total dummies?

I'll defer to consensus but I am quite comfortable with DiracLive.

Another issue is lossless master volume/mute control. I don't think any of the above MCH DACs have a wireless remote. My player for music DVDs and BDs via my PC's BD drive will usually be JRiver. Apparently, volume/mute control via its interface is lossless. https://yabb.jriver.com/interact/index.php?topic=137785.0

Do you agree? Or is there a better (handheld?) solution?

Agreed. I have a wired VC knob on the desk/rack next to the monitor used for Jriver and mirror my display on my iPad. Jriver deos offer their own remote apps.

 

[dped90]

I'm re-reading Floyd Toole's book, Sound Reproduction* and he says the center speaker is the most important with movies & television.

I don't doubt it, but a center channel speaker seems problematic in my case. I couldn't afford a third speaker like this https://josephcrowe.com/products/speaker-system-no-2095 , nor would I assume it would be appropriate as a center channel speaker for movies. I'll ask Troy when the time comes. But my TV's 65" and this one's much too large for that and for my room. https://josephcrowe.com/products/speaker-system-no-2015-10-mtm-with-1-4-horn

In any case, if the drivers in the center speaker are totally different than those in the mains how would that impact overall tonality, coherency and other important performance parameters?

 

[dped90]

USB mic does not require an ADC. I plug the mic directly into any one of the USB ports on the PC that I use with the HAPI.

So if your mic has a built in ADC, then you didn't need to install that Hapi MCH ADC card?

Please recommend a make/model mic.

Yes, as I recall you're a long time SACD collector, so you must have installed the Hapi DAC board with DSD capability, which is only for decoding ripped SACDs?

 

[dped90]

Agreed. I have a wired VC knob on the desk/rack next to the monitor used for Jriver and mirror my display on my iPad. Jriver deos offer their own remote apps.

Wired?? In the 21st century?? Those Merging turkeys are just being lazy or cheap. As per our chat here also today https://audiophilestyle.com/forums/...-ahb2-power-amplifier/page/4/#comment-1281466 , and given the number of NON-pro audio users of the Hapi DAC by now, we need those like Stereophile's Kal Rubinson to persuade Merging to do the right thing. There has to be some kind of USB add-on that will at least provide master volume/mute wireless remote functionality.

 

[Kal Rubinson]

So if your mic has a built in ADC, then you didn't need to install that Hapi MCH ADC card?

Please recommend a make/model mic.

Any calibrated(!) USB mic will do. The default is the miniDSP UMIK-1 but you can spend more.

Yes, as I recall you're a long time SACD collector, so you must have installed the Hapi DAC board with DSD capability, which is only for decoding ripped SACDs?

Yes.

Wired?? In the 21st century?? Those Merging turkeys are just being lazy or cheap.

Nah. It's not them. That's exactly where I want it. That's where I select and organize my program and set the level.

we need those like Stereophile's Kal Rubinson to persuade Merging to do the right thing.

I've asked more than once. Remember, their target market sits at a mixing/mastering desk.

There has to be some kind of USB add-on that will at least provide master volume/mute wireless remote functionality.

I can have the HAPI webpage on my phone and adjust volume/mute but, yes, a dedicated little wireless RC would be nice.

 

[DWPress]

You might also consider the Okto Dac8 Pro for MC DAC. You can order one with more than 4V output and bonus - it has a remote.

 

[dped90]

You might also consider the Okto Dac8 Pro for MC DAC. You can order one with more than 4V output and bonus - it has a remote.

Like StaticV3 said, I'd first have to get a (calibrated!) mic, like the UMIK-1 , install DIRAC Live, learn how to do measurements and create corrective filters-AND THEN see how much gain loss I may have before choosing a DAC.

Agreed. I have a wired VC knob on the desk/rack next to the monitor used for Jriver and mirror my display on my iPad. Jriver deos offer their own remote apps.

Will I lose resolution by using the up/down keys on my wireless keyboard to control the Hapi's master volume via JRiver? If no, then what Windows or other drivers must be installed-AND where-to ensure lossless audio attenuation via keyboard?

Or is this the only way to be sure? https://www.droking.com/USB-Controll...omputer-Laptop