Using CD player without Preamp?

I agree with Polk as long as the output stage was actually designed to drive a power amp. Despite having a nominal output high enough many CD players will not be as good as a good preamp in driving a power amp. But if they have been designed to do so then adding anything else will degrade the sound to some degree.

Stan -- You made a similar statement in the other recent thread that you referenced, which was questioned by another member. Please explain how the output stage of a cd player would "know" whether it is driving a preamp or a power amp, assuming the input impedances of the preamp and power amp are comparable, and the cable length that would be run to either device is the same. Also, how is one supposed to know if the output stage of the cd player is "designed to drive a power amp"?

I can certainly envision reasons why a specific combination of cd player and power amp might sound either better or worse with or without a preamp in between, some of which were mentioned in the other thread:

http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1228927169

But pending your answer I would not speak of a cd player as being "designed to drive a power amp."

Regards,
-- Al

Stan -- Thanks for your response. I took a look through the Audio Synthesis site, and I believe that their most relevant statement to this question was in a description of the DAX Decade D/A, which I think was a predecessor to the model you have:

The final analogue output signal is immaculately behaved and capable of a direct connection to any power amplifier over any choice of cable and without concern for potentially damaging operational transients which are expertly handled by intelligent muting. To offer such a direct connection we have carefully optimised the DAC and designed it to work at low output levels with extremely low noise and dc offset. Such low background noise level allows the use of more sensitive loudspeakers with an 8 ohm sensitivity figure in excess of 90dB/W/m if preferred.

To me, all of that adds up to simply having a quality well-designed output stage, that is capable of driving the cable, the load impedance, and the level and gain characteristics of the component that it is connected to. Whether that component is a preamp or a power amp I don't think is in itself particularly significant.

If the output stage has excessive noise or dc offset, putting a preamp in between the player and the power amp will not help (except in the specific case where the power amp is dc coupled and the preamp provides ac coupling that eliminates the offset). If the output stage cannot drive the cable or the input impedance of the power amplifier it is connected to, it is equally unlikely to be able to adequately drive a preamplifier, assuming similar cable lengths and input impedances. If it does not adequately control potentially damaging transients, it is just a poor design and having a preamp in front of the power amp is not likely to help.

So I still don't think it is quite right to speak of a cd player or dac output stage as being "designed to drive a power amp." I think the right perspective is that the output stage should be selected to be a good match to whatever cable and load device it will be working into, and beyond that it should simply be selected to be a quality design.

Regards,
-- Al