Why do I need a separate dac?

[Head_Unit]

if recently manufactured should be transparent in terms of measurement and audibility.

I'll echo the idea this is not guaranteed. Just look at the various reviews where products (of all stripes, not just DACs) fail to meet the dynamic range of a CD. And while the D/A conversion part is probably licked by now, the analog parts are still subject to cheap-ism: common power supplies, too weak to regulate well, cheap analog parts. Then again even a $9 Apple dongle can measure* and sound pretty good while so miniaturized it fits in a connector, just a stunning feat of audio engineering. Did I mention it's only $9? It's only $9.

*apparently the USA version, not the Euro one.

 

[RayDunzl]

What digital component other than a cd transport needs a separate dac?

Any component where you may choose to use its Digital Outputs, whether or not it has its own analog outs.

So, in my case, the CD Player, TV, PC, Oppo, DEQ2496, MiniDSP OpenDRC-DI, Focusrite Clarette, and HDRadio all route through a switch to the central DAC.

 

[Ritz]

I'm not sure I subscribe to the view that "they are mostly all the same." Judging from what I see on the measurements here, I'd say that there are a number of DACs out there that have artifacts that are so far below the threshold of hearing, that they are effectively the same. That's one of the things I love about this site. Just show me the data. I don't care about fairy dust and unicorns. If there was a sonic difference, we'd be able to measure it to within the realm of human perception. So pick a DAC that's above that threshold and you shouldn't be able to "hear a difference."

Best,

 

[formula 977]

route through a switch to the central DAC.

By 'switch' do you mean the equivalent of a normal analog preamp for digital input selection and gain control? What advantage do you have over the analog out from each of your components?

 

[Chrispy]

You probably don't. I went external a coupla times in the last few years....made no difference. Good luck, tho.

 

[RayDunzl]

By 'switch' do you mean the equivalent of a normal analog preamp for digital input selection and gain control?

By switch I mean an optical/coax S/PDIF switch

https://www.audioauthority.com/downloads/literature/1177a_ci_focus-sheet_2008-8.pdf

There is a traditional preamp after the DAC, connecting to two sets of speakers (Zone 1 and 2 outputs), and that is where I apply volume control remotely.

What advantage do you have over the analog out from each of your components?

There may or may not be any, but this is how I choose to operate the gear.

If there are some, I can point to common volume when switching sources, automatic switching to the active source, all sources have the same DSP applied, things like that.

 

[Berwhale]

Why use an obviously defective implemention of a dac to prove your point?

My point was that DACs could be incorrectly implemented, even in a device that is otherwise well designed and regarded.

Has anyone heard a difference between the correct implementation of the ESS dac and one with the ESS hump? Again, separate vs integrated and audibility.

I don't recall anyone on ASR claiming that the ESS hump was audible, I certainly wouldn't. So maybe not the best example to choose for this discussion. However, I chose this example because it is a well documented issue (on ASR) and has been investigated and solved by several manufacturers and ASR members and the issue is known to be related to the components connected to the DAC chip i.e. 'the implementation'.

Personally, I don't see the need for a stand-alone DAC if the DACs in your other equipment are performant. I was happy to replace my Topping x50 stack (D50s/A50s/P50) on my desk with a Topping EX5 (integrated DAC/HP & Pre-amp) because the EX5 solved a ground loop issue (balanced output), is neater both on and under my desk (single unit, no interconnects, single integrated PSU) and easier to use (bigger display and volume control).

From a measurement perspective, the EX5 is a 'downgrade' from the x50 stack (in the HP amp, rather than the DAC), but the benefits I mention above far outweigh any concerns I might have about this, to me, inaudible difference,