Am I using TWO preamps?

indus · 12-11-2009, 4:51 PM

Hello. Whilst talking about something else on another forum somebody pointed out that I am using two preamps and that 'is not recommended' as he put it. Is that true?

I have the fixed analogue output from my Quad CD player (that has built in preamp) going into the analogue input marked 'CD' on my Onkyo 875. I then listen to 2 ch music in the 'pure direct/audio' of the Onkyo, with the volume adjusted via the Onkyo.

Thanks

Mr_Orange · 12-11-2009, 5:14 PM

Doesn't sound like it. A fixed output should bypass any preamp stages in the Quad and be like the stereo output on any other CDP.

mikeg1975 · 12-11-2009, 5:26 PM

I agree, I think you're fine. According to page 16 of the manual there are both fixed and variable outputs with the former bypassing the internal volume control etc. If you were connecting the variable output to your Onkyo then that would be a problem but as it is I'd say you were ok.

Mike

Welwynnick · 12-11-2009, 5:55 PM

What he's probably referring to, is that you are using active analogue circuits within the Onkyo to carry the CD audio, and these amount to a line-level pre-amp. Perhaps he is implying that you should use an spdif connection to minimise the analogue circuitry. Thats a point, but I wouldn't necessarily agre with it. The analogue connection may actually sound better. I would suck it and see - it will sound different, but it mightbe difficult to decide which is better.

nick

indus · 12-11-2009, 7:07 PM

Thanks guys.

Nick, I'm confused about what you said about avoiding the active analogue circuitry of the Onkyo by using a spdif connection. If I outputted a digital signal
from the CDP to the Onkyo, then the signal would have to be converted to analogue anyway wouldn't it? Ie the DAC in the Onkyo would be used, as opposed to the (hopefully) better quality DAC in the Quad.
How could that even theoretically be an advantage?

Also, can you tell me, is the preamp in the Quad being used, or only the one in the Onkyo?

Thanks

Welwynnick · 12-11-2009, 8:01 PM

I expect the signal coming out of the Quad DAC will be better than that from the Onkyo, which doesn't work very well with spdif or toslink inputs, either compressed or lpcm. However, it would have to go through an analogue stage in the Quad plus an analogue stage in the Onkyo, in addition to what would happen with D to A conversion in the Onkyo. This is based on a description of the Onkyo schematics by someone on a well-known US forum. Whether this means the analogue or digital connection is better, I'm not sure. I'd expect analogue from the Quad would be better, but I would definitely compare them.

Nick

indus · 13-11-2009, 6:35 PM

Quote:

Originally Posted by welwynnick

I expect the signal coming out of the Quad DAC will be better than that from the Onkyo, which doesn't work very well with spdif or toslink inputs, either compressed or lpcm. However, it would have to go through an analogue stage in the Quad plus an analogue stage in the Onkyo, in addition to what would happen with D to A conversion in the Onkyo. This is based on a description of the Onkyo schematics by someone on a well-known US forum. Whether this means the analogue or digital connection is better, I'm not sure. I'd expect analogue from the Quad would be better, but I would definitely compare them.

Nick

Many thanks. I will try the digital output of the Quad for comparison.