DAC disables built-in Mac audio controls

[ScottCitron]

I bought a DAC to attach to my iMac. The I love the sound when listening to music in iTunes, but attaching the DAC also disables the computer's built-in audio controls. This means any computer alerts or sounds come through much too loud, and all audio level sliders are dimmed out, giving me no way to control the computer's built-in audio levels. Is my only option to now buy some kind of preamp to add to the audio chain? Or is there some other way to do this? Again, I'm on Mac OS 10.8.2 and would appreciate any and all suggestions. Thanks.

[wgscott]

This is actually how it is supposed to work.

 

First thing to do is turn off all the system sound effects and stuff like that, in the System Preferences "Sound" preference pane.

 

Then you should experiment with how you can control volume.

 

The simplest way is to use the iTunes volume slider. This has disadvantages, in that the output is dithered or resampled, it is no longer bit perfect.

 

You can either do it this way (or with a more sophisticated volume control, like that in Audirvana Plus), or use a pre-Amp or passive buffer (as what you are really doing is attenuating the signal).

 

The first approach is digital control, and has the advantage of being free (in iTunes) or relatively cheap (eg Audirvana Plus). The second approach has the advantage of controlling the volume at the analogue stage, so you aren't digitally resampling your music.

[ScottCitron]

Yes, I understand that DACs by nature take over a computer's audio output control. Nonetheless, employing the DAC is not without some problems, as I noted. I tried turning down or off the computer's alerts, which may be the only real solution. Will also check out the Audirvana Plus as well. Thanks.

[ScottCitron]

The Audirvana Plus looks like the ticket. Without it, iTunes is WAY TOO LOUD!! There's no way to really control the volume with the iTunes slider. At least with Audirvana I'm able to once again regain normal control. Many thanks for the tip; much appreciated.

[wgscott]

This is a very frequent topic of discussion, so there are a large number of opinions.

 

The problem arises because most people want bit-perfect output to their DAC, which means the system volume and iTune's own volume (or whatever player software's) volume is set to the maximum value.

 

The signal from a DAC generally has to be attenuated. Probably the least compromising approach is to use a passive buffer rather than an active pre-amp, e.g.: DODD AUDIO - Buffer. If you have multiple components rather than just this one DAC, it might be more appropriate to use a conventional pre-amp.

 

Knowing what your amp and speakers are, and other requirements, would probably help others give better advice than what I have come up with.

[ninjagosg]

hmmm do you have your alerts and sound effects routed to your dac in addition to your main sound output?

 

in my case i have my main sound output --> dac and my alerts and sound effect --> imac's built-in speakers. i can adjust the levels separately using Audio MIDI Setup or Preferences -> Sound

[ScottCitron]

WGScott: After spending $50 bucks and some time with the Audirvana, I'm back where I started. The problem is that the Audirvana only controls the audio level from iTunes. All other useful system sounds are way too loud. Plus, it's nearly impossible to Quit Audirvana with iTunes open; it forces itself open whenever it sees that iTunes is open. Overall, it's just too invasive and makes listening to music on my iMac too complicated.

 

There MUST be a simpler solution to using a DAC with my computer. I looked at the DODD Audio-Buffer, but $1500 is overkill for this problem. There must be another way, no? Ninjagosg (above) talks about routing his main sound to his DAC and his alerts and sound effects to the iMac built-in speakers. But when I plug in the DAC via Toslink, I'm not able to send alerts and sound effects to my built-in speakers. Everything goes to the Digital Out.

[ninjagosg]

hmmm, using the imac's optical out might limit your flexibility in this case plus limit digital output to 96/24. for my setup, i use usb to connect to my nad m51 dac and in audio midi setup, i'm able to set them separately

 

if your dac doesn't have usb input, maybe you'd like to use a usb-to-spdif/aes-ebu converter? the musical fidelity v-link 192 connects to your mac's usb and outputs to coax and aes/ebu. selling for USD199 (USD399 SRP) from some online stores in the us, i find it's one of the cheaper usb-to-spdif/aes-ebu converters. i'm not sure about other options though as i'm quite new to this stuff, plus most of the ones i looked at lacked aes/ebu

[Audio_ELF]

To be honest it sounds like you have bought the wrong DAC for your situation...

 

Perhaps if you described what equipment you have we may be able to make suggestions better.

 

People are talking about using optical connections and USB to SPDIF converters but I can't see how that will improve things for you.

 

Eloise