A DAC into a DAC?

Keeping everything digital should just pass the digital signal through from your source to the dac. The data will only get decoded once.

If you are using 2 channel only and the pre/pro is staying on as the preamp, just run the source to the dac to a pair of analogue inputs in the prepro.

You could compare the 2 dacs and see what you like best.

What brand and model pre/pro are we talking and the same for the outboard DAC?

If you have a superior outboard DAC, it will convert to analog and then enter your pre/pro. If the analog stage of the pre/pro is of low quality, then it may hamper the sound quality.

You probably should be a little more specific to give us a better idea of how to better answer your questions.

I have a Cambridge Audio 840C player/DAC that is of pretty high quality that goes in to an also pretty high quality NAD T175HD pre/pro. I use the CA 840C's DAC to convert and upsample(24/384)a Pandora stream from my Samsung TV and it does a better job than the T175HD's DAC. On the other hand, when I play redbook CD's, I mainly use the 840C as a transport only selecting the "pass through" setting with no upsampling and let the T175HD do the D/A converting.

Bill

"If I insert (between my source and the pre-pro), a new DAC that’s SUPERIOR to the pre-pro’s DAC, I assume that the pre-pro would limit or degrade the SQ of the new DAC. Correct? Is feeding the signal from the pre-pro an option in this case?"

ANY preamp will add some distortion, compression and noise to the analog signal, but you need some way of controlling volume and achieving a low-output impedance drive to your amps in order to get decent dynamics.

Most decent DACs (over $1K) will outperform the DAC in a SS processor. All you need to do is feed the analog outs from the DAC to the SS proc and control volume with the SS proc. This will probably improve the SQ over the SS Proc. internal DAC, but you have the preamp adding noise and distortion.

A better solution is to get a DAC with good output drive and replace the SS proc. with a transformer-based linestage like a Music First.

Another option is to get a DAC with good output drive and a good volume control technology and replace the SS proc. This is what I do. In order to insert other analog sources such as home theater or vinyl, I use a Final Drive after the DAC and before the amps.

Final Drive:

http://www.empiricalaudio.com/products/final-drive

Steve N.
Empirical Audio

Thanks for your responses so far!

The Pre-pro is an Onkyo PR-SC885, and I assume it's of pretty good quality with those Burr-Brown's.

As for the outboard DAC, I am hoping to A/B several, and I haven't bought one yet. But the Wyred 4 Sound DAC2 is at the top of a short list.

Michael

Most modern DACs like the DAC2 have a HT bypass input.

You can hook the Onkyo's preamp output to the DAC2's HT bypass input.

The DAC2 then feeds the power amps.

When you are listening to 2 channel sources, use the DAC2 (with your digital sources feeding the DAC2).

When you are watching a movie, switch the DAC2 to the HT bypass input, and the Onkyo will play the left and right channels through it (at unity volume gain) to the L and R speakers. You may need to run Audyssey again on the Onkyo to ensure the volume levels are set correctly.

"The Pre-pro is an Onkyo PR-SC885, and I assume it's of pretty good quality with those Burr-Brown's."

I would not consider the Onkyo good quality just because it uses a particular chip. Its the design, implementation and particularly the power supplies and regulators that make a good DAC.

I have owned a lot of mid-fi stuff in my 40+ years of upgrading, including Onkyo and Denon. Not even in the same league as good audiophile grade equipment. Sounds like stereo, not music.

I have listened to the most expensive SS procs and non of them stack up to a good DAC.

Steve N.
Empirical Audio