Bypassing the preamp - benefits? risks?

Posted by: jayd on 24 April 2003

As you all know, certain cd players have a volume control built in, enabling (at least in theory) an ultra-simple two-component system wherein the cd player feeds the amp directly.

I understand that for most (maybe all) applications, component matching, etc. makes this a bad idea. However, I'm curious how it plays out in a system designed for such an application, e.g., a Linn Genki feeding an appropriate Linn amp.

From the Linn website: "With both fixed and variable outputs, the Genki can be connected to a preamplifier in the conventional way or, using its local volume control, connect directly to a power amplifier. Why not combine the two to provide a simple 2-room system."

I must admit that this approach appeals to the minimalist in me. So I ask you knowledgeable folks the same question Linn asks - why not?

I know, I know... "Get a 3.5 - blows the knickers off any Linn" or maybe "This would work well provided your system resides on phase googol Mana supports" etc., etc. I'm more interested in the inherent risks/benefits of the approach as stated. Input from Linnies (especially ones who might have tried this) is especially welcome.

Thanks for everything.

Jay

[This message was edited by jayd on THURSDAY 24 April 2003 at 20:31.]
Posted on: 24 April 2003 by DAVOhorn
Dear Jay,

I use a pioneer cd player with a built in volume control.
CD players output is usually more than sufficient to run a power amp directly.

Advantages one less stage of amplification for the signal to pass through. Less interconnect for the signal to pass through. So less losses in the system. Also more money to spend on cd's as you have not spent on a pre amp.

Diadvantage is that you can only put cd player into system as cd output is effectvely the pre amp.

So my cd player is going into a pairof QUAD 11 power amps into a pair of my own design of loudspeakers.
Very nice sound too.

regards David
Posted on: 24 April 2003 by Bob Shedlock
As James pointed out, a digial domain volume control as seen on some CD players would be a vast sonic compromise.
In theory the elimination of another level of electronics would have a beneficial effect. Still, as pointed out above, impedance has an effect, but also buffering provided in preamps works to a listener's advantage. At least in my experience.
I've also used some highly regarded passive preamps which never had the bass drive or incisiveness obtained with active pre's.
Although it SHOULD be better, in the real world I've found a well designed preamp to best straight-through or passive preamps.
Posted on: 24 April 2003 by JeremyB
You can use a Naim amp without a separate naim pre-amp - it's called a NAIT-5. Anyone want to second a request for a 500/552 class integrated from Naim? One input and a volume control is all I need. It'll never happen though.
Posted on: 25 April 2003 by Phil Barry
My old TOL SOny ES had an analogue volume control. SO does my HK tuner. I wanted to use them to equalize the volume with LPs (i.e. so I wouldn't have to adjust volume at the pre when I changed sources).

Both CD and tuner sounded much worse through their own variable outputs than through their fixed outputs.

Phil
Posted on: 25 April 2003 by Nigel Cavendish
I read some time ago in Stereophile(?) that some US listeners were putting the output from a CD player with built in volume control directly into valve monoblocks with very good results.

It does raise the question of what is a pre-amp other than a very expensive volume control.

cheers

Nigel

Posted on: 25 April 2003 by Stuart M
Happily driving a 140 from a Yamaha DSP-E800 for my AV speakers. When I contacted Naim about the best way to do this I I was told I just needed to make up a 2 phono to 4 pin din, no mention was made of any problem.

To err is human; to really foul it up requires a computer.
Posted on: 27 April 2003 by Geoff P
I have driven a 150 via my Denon AVR3802 pre outs DIRECT with no problem. Naim when asked commented "that it was not ideal but that particulalrly in the case of the 5 series it would work OK since the newer amps were less sensitive to what was feeding them".

The Denon has the capability to process high bandwidth sources such as SACD / DVD-A and I have fed those to the 150 with no problems.

I say have because it was just a test to see if the Denon could drive the equivalent of a 157V if I decided to add Naim amping for the center and rear channels (waiting on funds).

For normal use the front channels currently go thru'a 112 + HiCap using unity gain and in my opinion benefit from the "passive" use of the 112 compared with straight into the 150.

regards GEOFFP
Posted on: 14 August 2003 by prowla
I previously ran a Meridian 207 CD player/preamp into a Naim 140.
My Linn/Naim dealer made up the phono-DIN cable for me.
(I've still got the 140, but not the Meridian.)

Paul Rowlands