Benchmark DAC1 configuration


Hello all.
I've exhausted just about every possible avenue to try to figure out both the "best" way to hook up a Benchmark DAC1 (not PRE or USB version), and the "appropriate" way. What I mean is (please bear with me):
1. Has anyone out there had any experience having this unit perform as a preamp fed directly to an integrated tube amp? If so, can it be done with RCA interconnects (not balanced) going from the output to amp and another pair from CD player to amp (uncertain how/if this would work; I assume not?

2. If serving solely as a DAC fed into a CD player as transport, what is, in your opinion, the best cable to use (not so much brand, but cable type — though brands are welcome)?

Apologies if this is a bit newbie, but this is my first DAC, thus I am very unfamiliar with the logistics.

Thanks all.
jsawyer09
Yes you can feed it to an integrated. Just use any analog CD player or aux or TV or VCR RCA inputs but DO NOT use the phono input. Adjust the volume of the DAC1 so you ensure you do not overdrive the integrated.

The digital cable you use will depend on what digital outs are avalable from your CD transport. Either SP/DIF or Toslink should work well.
Not sure what you mean by "perform as a preamp fed directly to an integrated amp." An integrated amp contains a preamp, by definition.

Also, re "if serving solely as a dac fed into a cd player as transport," the cd player or transport feeds the dac, not vice versa.

Basically, a dac (digital-to-analog converter) takes as inputs the digital outputs of a cd transport, or of a cd player used as a transport, converts its digital inputs into analog outputs, which are then fed into a preamplifier or integrated amplifier (or possibly directly into a power amplifier, if the dac provides a volume control function and sufficient output amplitude).

The dac has to have digital inputs provided to it or it will not do anything. If when you referred to connecting both the dac outputs and the cd player outputs to the integrated amplifier you meant that the cd player's digital outputs would be connected to the dac inputs, and the cd player's analog outputs (as well as the dac's outputs) would both be connected to the integrated amplifier (on separate amp inputs), that would probably work. But the only reason for doing that would be to facilitate switching between the DAC1 and the cd player's internal dac, perhaps for comparison purposes.

The reason I say "probably work" is that it seems conceivable (though unlikely) that having the components connected that way (cd player digital outputs to dac; cd player analog outputs to amp; dac analog outputs to amp) might introduce some amount of hum, due to ground-loop effects.

Regards,
-- Al
Lots of options for output from a Benchmark DAC. It has both RCA and XLR outputs. And you can set the output to be a fixed level, like any regular CD player or any any other component. Or it can give you a variable output that goes through the front volume control like the output from a preamp. Selecting variable or fixed output is done with the small switch on the back - down for variable or up for fixed.

If you are connecting to an integrated amp, you would probably want to use the fixed output setting and let the integrated amp control the volume. If you were connecting it to a power amp (no volume contol on the amp) you would want to use the variable output setting. Make sure you start with the front volume control turned down in that case. The headphone jacks on the front of the DAC1 go through the volume control knob no matter what the setting on the back.

As far as digital inputs, that will depend on what kind of digital output(s) you have on your transport. You can find different opinions on which input is the best. I used the SPD/IF (BNC) input when I had a DAC 1. SPD/IF will come out of most transports with a RCA type connector. The DAC 1 should have a RCA/BNC converter included with it. Or do like I did and get a digital cable with RCA on one end and BNC on the other end.
Thanks so much, each of you, for responding. It really helps and is much appreciated.

Almarg, I just wanted to see if anyone has bypassed their preamp stage in a tube integrated with the DAC1; wondered if it performed better than one's integrated pre. Also, duh on my part; I wrote the transport part wrong (but I appreciate the correction). As for your clarifying paragraph regarding comparison purposes, that was really very helpful. I just couldn't logistically figure how this would be connected. However, I do see what you're saying, and I certainly do not wish to introduce interference of any kind. I've read people using it as a preamp with good results; but as a DAC, it's been well-received, too. I guess I wanted to hear if people had any comparisons between the two configurations secondarily, but the "how-to" first and foremost.

So with that, maybe it's just simplest (cable-wise — both sheer number-wise used in conjunction with different types) to use it as a DAC, and choose a good digital (as my CD player is a Cambridge Audio 740C) cable as Sonofnorway has illustrated. I have several types of cables, but use AP Solo Crystal Ovals throughout. So, maybe an AP Digital Oval cable would work well (this is where brands would be welcome from anyone).

Sonofnorway...we'll talk offline (sent you an e-mail).
Thanks again everyone!
JSawyer09 -- You're welcome!

As you probably realize, you would only be able to truly bypass the preamp stage in the integrated amp if it provides preamp-out and power amp-in jacks on its rear panel. These would normally be jumpered together, and to bypass the preamp stage you would remove those jumpers and connect the dac1 output to the power amp-in jacks. Many (most?) integrateds don't provide those jacks, though.

If you wish to do so, there would be no harm in trying the setup I described with cd player analog outputs and dac1 analog outputs both connected to line-level inputs of the amplifier. That will most probably work ok, as I indicated, and if hum problems resulted they would be immediately apparent.

Regards,
-- Al