HiFi preamp to power stage interface

Phil_aka_Pip

If your phono stage, your CD machine, your tuner, your cassette machine, your video audio output etc are all at line level, what exactly does a pre-amp do for you, if your power stage will accept a line level input? Could you get away with a signal switch box and a volume control? Is there really any need to buffer the signals with more active devices?

Hope that's not a silly question. I have various signal sources connected to a Conrad-Johnson preamp, and its output goes to a Leak Stereo-20 via a QED volume control box because the CJ preamp puts out too much for the Leak's input sensitivity. I also have in my music room a Studiomaster Series 5 desk whose monitor outputs go straight to a Quad power stage. Apart from that, all my previous hifi experience has been with integrated amplifiers so I've not had to think about it.

exocet

No reason why you couldn't do what you suggest, in fact I can recall about 30 years ago there was a huge trend for "passive preamps" i.e. boxes that contained inputs / outputs and a simple volume.
Traditionally, pre-amps provided buffering, switching, tone controls. The main "pre-amp" function was for the phono stage especially where low output "moving coil" cartridges were used.

Ravenous

Not a silly question at all. Passive preamps, as exocet just mentioned, are available in all the glossy hi-fi magazines.

They are sometimes incredibly expensive for just sockets, switches and volume pots though.  They really tend to go to town on brass, gold and pretty timber

prowla

There was even a fashion for directly connecting CD players (with variable outputs!) to a power amp.

If nothing else, the preamp does present a high impedance to its source, maybe support internal phono stages, and allow routing between inputs & outputs.

Phil_aka_Pip

Thank you, Gentlemen I may not need to add another expensive box to the Series 5 Radford (which is coming "in the new year") after all.

ESBlonde

If you just have the one output device (CD)? then that can go directly to the power amp at line level. A typical power amp does not have a volume control (even though it says that on the front). It's more an attenuator and the power amp is running full power all the time. If you have a casette or real tape, a CD, a turntable etc. a preamp enables them all to interconnect for transfer/recording and output to the power amp too, all while listening on headphones! It's like a fancy mixer without calling it one.

richardhomer

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

Lodious

richardhomer said:

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

.....and the extra power supplies for preamps

richardhomer

Lodious said:

richardhomer said:

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

.....and the extra power supplies for preamps

And £500 mains leads to connect to them...

Phil_aka_Pip

richardhomer said:

Lodious said:

richardhomer said:

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

.....and the extra power supplies for preamps

And £500 mains leads to connect to them...

You are Russ Andrews and ICM £5

prowla

richardhomer said:

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

I used to use a Naim 140 power amp with a Meridian 207 CD player/preamp.

prowla

richardhomer said:

Lodious said:

richardhomer said:

Some power amps - specifically Naim - are bandwidth limited by their matching pre-amps - with dire warnings that things might go ‘pop’ if you used them with anything else.

Whether this is still the case, I don’t know. I suppose it helped sell pre-amps....

.....and the extra power supplies for preamps

And £500 mains leads to connect to them...

Well, right now I have a Naim CD player, with dedicated power supply, a Naim pre-amp, with dedicated power supply, and a Naim power amp. Also with a rather expensive Naim interconnect from CD to pre-amp and a mutli-way "hydra" mains lead I made which is housed in a Naim case.

richardhomer

Phil_aka_Pip said:
You are Russ Andrews and ICM £5

Wrong - I was referring to Naim’s own cable:

http://petertyson.co.uk/index.php/naim-power-line.html?gcpc&gclid=EAIaIQobChMI582Aoqr21wIV6LztCh1BEgssEAQYASABEgLj6PD_BwE

Phil_aka_Pip

they must be just as crazy as Russ Andrews

richardhomer

Phil_aka_Pip said:

they must be just as crazy as Russ Andrews

I’ve been a Naim customer for a long time - though I only have a one box streamer now. I have to say the mains lead disappoints me. £530 is outrageous....