Stereo amplifiers... a bit confused

[pstruck]

This may be a silly question, but I need enlightening!

What are the differences/benefits of using separate pre and power amps over an integrated amp? I've seen it suggested that a power amp can be paired with an integrated amp - is this correct? Why might you do this?

[parapaul]

Isn't it just power output? AIUI you can use your stereo amp as a pre-amp if it has the right connections...

[jet_noise]

Dear pstruck,

IMHO Separation. Different boxes, different power supllies. The preamp operating at low levels is therefore not affected by the big currents/power supply transients and heat generated in a power amp.,

regards,
Jet

[Mr_Yogi]

As Jet said, separation. When you start getting into high end amps with hundreds on Watts of power output, you need big power supplies. However the pre-amp stages operate on tiny line level signals, so you want a very small clean power supply for this stage, in fact you cna even get passive pre-amps that have no power supply at all.

Also separate boxes allows more flexability and eases upgrading. You can use of a pre-amp with a stereo power amp, or a pair of mono block power amps (one power amp for each speaker). You can even run two or more stereo power amps and have each speaker drive unit driven with it's own power amp channel (known as bi or tri-amping, depending on the number of drive units and amps required). The logical step from there is bi/ tri-amping with 4 or 6 monoblock power amps, where each driver unit has it's own power amp.

After this you move to active speakers/ crossovers, but you still need a pre-amp.

As for combining an intergrated with a power amp; this might allow you to use the integrated as a pre-amp. Thus cutting down on the interferance caused by the power amp stage/ current draw in the integrated, so cleaning up the pre-amp stage. Also the extrnal power amp might be on higher quality than the power amp stage built into the integrated. Another option might be to bi-amp with the power-amp stage of the integrated feeding the tweeters and the separate power amp feeding the woofers.

Edited by Mr_Yogi on Tuesday 23 March 10:37

[pstruck]

Thanks for the responses guys. Good detail there Yogi. That all makes sense.

Whether or not it makes a worthwhile upgrade for a home system I guess depends on listening preferences, size of room, and probably numerous other factors.

[liquidken]

Regardless of room sizes and the other external influences that go with it, if you enjoy your music, there is substantial merit in going down this path.

The key thing to remember is that the better the system, the more information you get - particularly at lower levels.

As much as some integrated amps have bundles of musicality, staging and grip on the music, they never seem to afford the level of separation afforded by even some cheaper 'separate' alternatives.