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JonW
10-23-2005, 07:00 PM
I’m gradually building up my stereo system. It looks like I might have a CD player, an amp, and a pair of speakers for a little while. And the CD player happens to have a volume control on the remote. So can I just use these 3 pieces and listen to music for a while? Or do I somehow need a preamp or a preamp-processor? More equipment is on the way, in the coming months. But in the mean time, maybe this very simple setup would work, I’m thinking. (And if it would work, why don’t more people do it?)

N. Abstentia
10-23-2005, 07:01 PM
As long as the CD has the volume control, you should be good to go.

trollgirl
10-23-2005, 07:16 PM
...without a preamp in the signal path. Less circuit = better sound (generally).

Laz

RGA
10-23-2005, 07:27 PM
No the sound will not be better imo. CD Players that have volume controls ARE preamps usually the worst ones known to man. But then cd players are pre pre amps anyway because they vary with their output stage as it is. I've tried the experiment several times and it always sounds bad to me. Concieveably though it could depend on the cd player and how much attention they pay to it.

Though as always, your mileage may vary :cool:

kexodusc
10-24-2005, 03:51 AM
[QUOTE=RGA]No the sound will not be better imo. CD Players that have volume controls ARE preamps usually the worst ones known to man. But then cd players are pre pre amps anyway because they vary with their output stage as it is.QUOTE]


A small voltage gain stage in a CD player is pretty harmless and easy to pull off. If your amp can "hear" the input (and perhaps has an adjustable gain feature of it's own) you should be fine.

What RGA alludes to though, is the problem starts when you see cheaper CD players with gain stages that really need to be cranked and start clipping - that's bad. They just aren't made for that function. I think volume controls on a CD player should be used for quick muting, or level matching components (if so desired) and that's about it.

I've had mixed results. On some gear I had, skipping the pre-amp worked quite well, on others, not so good.

With all the used gear out there, you should be able to find a cheap integrated, or receiver with preouts, or a budget pre-amp for not too much money. You'd be further ahead than using your CD player to boost the gain, IMO.

JonW
10-24-2005, 10:34 AM
HI Folks,

Thanks for the responses. Good to hear this should work out OK. It's only a temporary situation. I'm looking around for a used preamp-processor that I decided on (Audio Refinment Pre-2DSP). When I find one at a decent price, I'll get that. But no big hurry. So in the mean time, my speakers that are on their way (Totem Forests) can be used. That's good. :)

Actually, the amp is also temporary. I'm at the beginning stages of building a sub. The amp that is also on its way is for the sub (Carvin HD1800). So with my current CD player, the Carvin amp, and the Totem speakers, I can at least listen to some music until the sub is built, the pre-pro is found, etc. I'm thinking about picking up a used PS Audio HCA2 for the main speakers. I heard a PS Audio GCA-100 and liked it, so maybe I'll get a used HCA2.

E-Stat
10-24-2005, 12:48 PM
But in the mean time, maybe this very simple setup would work, I’m thinking.
I've used passive attenuators in two systems with excellent results. There are, however, some potential impedance matching issues as well as gain. In many cases, though, a 20 db line stage is merely used to attenuate the signal.

With my main system, a line stage is definitely unncessary. I built my first attenuators for an office system and just for grins, took it downstairs to the main system. I was surprised that this $15 DIY Radio Shack box outperformed a $2500 Audio Research preamp both in soundstage width and resolution. I ended up making a nicer unit for it using stepped controls. The GamuT CD-1 has a 75 ohm / 4 volt output that can easily overdrive my amps. The cables are short and involve no HF rolloff. With the vintage system, I get good impedance matching, but cannot fully drive the power amp. That is really no problem anyway because I rarely listen above 80 db in the garage.


(And if it would work, why don’t more people do it?)
More folks are. I recently heard an incredible ASR Emitter amp that on one level might be considered an "integrated" amp since it has input switching and gain controls. What it does not have is a separate line stage. The input stage of the amp is designed specifically to work directly with phono preamps and CD outputs. Some of the built in gain controls on inexpensive CDPs truly are not as good as can be had. Neither of my CDPs has them built in - I built the attenators.

rw