HT, WHAT'S BETTER 2 CHANNEL + 3 OR ONE 5 CH

I have no argument with Markphd's statements but let me give you another take.

Since all the amps, regardless of how they are configured, are limited by the AC signal, you can optimize using separate amps only with dedicated AC lines for each.

Now, if you look at a multichannel power amp, regardless of the number of channels, you can have each channel with its own PS, in which case Markphd's arguments for separate amps applies here as long as the power cord is up to the task.

OTOH, if there's one really beefy PS for all the N-amps, it can supply much more to active channels when there's less demand from others. In other words, since there's rarely instantaneous and simultaneous power demand from all channels, the needy ones get help from what the others don't need.

Kal (who thinks it really makes no difference in general)

In my HT set up, I had a 2 channel and a 3 channel amp set up before. I ran of out space on my rack so I sold both and bought a 5 channel amp. I did not realized how much better the 2&3 were vs. the 5 alone. My amps were all from Cary and put out the same 200w/channel, so I guess that should answer your question.
Nick

In theory all things being equal, 5 monoblocs would be best, then 3 and 2 channels, and then 5 channels.

Just having 5 individual power cords and power supplie/transformers would make the monoblocs the best.

This is assuming that all electronics are equal, and the efficiency advantage of 5 blocs over a single chassis would and could be realized.

Even heat dissipation would be better, with larger radiating surface areas and more metal.

Five monoblocks are less likely to cause you a hernia.

I've built my multichannel-audio/video system around a 2-channel system. I use tubed monoamps (ASL Hurricanes in triode) for the L- and R-front speakers and a 7-channel Outlaw 770 for everything else. That 'everything' includes 2 channels for the dipole-woofered Eminent Technology 12 centerchannel, 2 channels for the bass modules of the Eminent Tech. 8s, and 2 channels for the surrounds. Works quite well. Previously I used a Proceed BPA-3 poweramp (125WPC times 3) for the fronts and a B&K 125.5 for the other channels.

Either way, the front-channel speakercables were and still are quite short, and the 2-channel system sounds great. If I had to start over, I think I'd do it the same way, ie monos for the 2-channel system and another Outlaw multichannel amp for everything else.
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