There are some awesome AVRs out there, but I think it's a big compromise to run long speaker cables all around the room. Nearly every speaker manufacturer recommends using equal-length speaker cables. So unless you use monoblocks for each channel, you defy that logic.
I am currently looking at getting the Anthem D2 v2 pre/pro and using the Focal SM Twin6 Be active speakers. This eliminates the long runs of speaker cable and allows the use of balanced cables, which I believe are much better in that situation.
I guess the biggest disadvantages with active speakers are needing a nearby power outlet for each one and not being able to choose an amp that sounds a particular way. Also, there are very few active speakers on the market for domestic use. I wonder why more speaker companies don't make active speakers for home theater?
Bottom linedo you believe that long balanced-cable runs are better than long speaker-cable runs?
Absolutely! You are entirely correct that long balanced cables are much better at rejecting interference and noise than long speaker cables. However, pre/pros with balanced outs are generally more expensive than many AVRs, and then you have to buy power amps or powered speakers, increasing the cost of the system even more. I agree that the best solution is a balanced-out pre/pro and a monoblock for each speaker (or powered speakers), but this is a very expensive approach that few can afford.
On the other hand, I've rarely had any real problems with AVRs and speaker cables, at least in smallish rooms. If the cable lengths are as short as possible (taking into account that the lengths for all three fronts should ideally be the same, as should the lengths for the rears), and the cables are routed carefully (avoiding proximity with AC power cables, for example), there shouldn't be a problem.
I don't know why more consumer speaker companies don't make active speakers. I've always been a big fan of this idea, which lets the manufacturer match the amps to the speakers. As you say, however, this prohibits the user from selecting amps that have the sound they want.
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