Using separate amplifiers (1 Viewer)

[Don K]

After reading some post on using a separate amplifier for your speaker I have a few questions. I'm a novice in this. Most amplifiers I see are two channel. How do you use the amps on a 5 channel system? I do have a Hafler two channel Amp and thought of using it for my right and left front speakers. Does the Center channel speaker also require amplification? If I do decide to use separate amps for all my speakers and also decide to up grade my receiver should I buy a preamp instead or a receiver with less wattage since I won't be using the receiver's amplifier?

 

[Evan S]

Don, there are 1, 2, 3, 4, 5, 6, and 7 channel amps on the market.

You can use your 2 channel amp for the main speakers and buy an additional 3 channel amp for a 5.1 setup or get a 5 channel amp for the Center, surrounds and rear surrounds for a full 7.1 setup.

Yes, the center channel needs amplification. What you can do right now if your Receiver has pre-outs is send the main left and right signals out to your Hafler and have the receiver drive the center and the surrounds until you buy another external amp.

My suggestion is down the road for better sonic quality...get another 5 channel amp for the surrounds and rears and go with a pre/pro. You might be happier with the sound but if the cost is prohibitive, you can get away with the receiver/amp combo easily.

 

[Drew Eckhardt]

If you want to use stereo amps for 5.1, you can buy three and ignore the extra channel or use it to power a passive subwoofer (fine examples of which can be had commercially for not a lot of money and can be built for even less).

Drawbacks are space (four 100W stereo amps eat most of a 3' rack) and heat (200-600+ Watts at idle). If you can live with that the sound is exceptional (you get big power supplies, which can be arranged so that you have one amplifier chasis (monoblock) per channel in stereo mode) and you'll really appreciate the severe depreciation on two-channel gear if you're buying on the used market.

Personally, I run 4 stereo amps - the first left over from my 2-channel setup, the last three picked up for 1/3 what they sold for originally on the used market.

You could also use one two channel amp for your main speakers and the receiver internal amplifiers for the rest (you notice the sound more in stereo listening, and a lot of output goes to the left and right speakers so getting them off the receiver power supply will make all the speakers sound better during loud scenes); a 2 channel amp for the front speakers and 3 for the surrounds and center; or other exotic configurations.

As far as the receiver vs. separate preamp: I ran a tuner/preamp for a while in my two-channel setup, and was never happy with what it did to the sound. I think it was gritty, but could never pin down exactly what it was - anything else was simply more natural. An audiophile friend couldn't describe exactly what it did to the sound either, although we agreed CD player->amp, a Marantz 7C inbwetween, various homebrew tube line stages, and the Lexicon DC-1 all did at least an acceptable job. I suspect the RF tuner in the same chasis as the line stage along with the poor engineering practices which plague audio gear. By definition all receivers have a tuner, and many examples have silly things going on inside the cases (heat sinks under circuit boards, unshielded ribbon cables meandering all over the place).

OTOH, if you want to buy new you could spend a huge chunk of change for a quality unit.

Needing component video switching in the same box ((1) The switches in many receivers don't have the bandwidth for HD, so they don't count and 2) With a dozen boxes in the equipment racks youo won't notice one more) and/or an analog pass through on the box (Sony makes a multi-channel analog only preamp which could be used as a work-arround if DVD-A or SACD really take off) will limit your choices, especially in the "economical" and/or used categories. DPLII will be hard to get as well in such products, although a lot of people prefer proprietary 7 channel interpretations (like Lexicon or Meridian's).

Receiver vs. preamp as a preamp is a point-of-reference/preference/religious issue that you'll find people argueing for on either side.