"molipix" wrote in message


I'm building up a sound system for our living room using
second hand parts. I would like to keep things as small
and unobtrusive as possible. So far I have a Cyrus II amp
- this has outputs for one pair of speakers (rated at 8
Ohms). My plan is to connect two small bookshelf speakers
like the Tannoy Revolution R1s and add a subwoofer. The
options as far as I can see a

1) connect a passive subwoofer in parallel with the
bookshelf speakers

Passive subwoofers operated from the same power amps as the mains have
pretty well fallen out of favor. The reasons are many. One is that they take
power away from the mains. Another is that subwoofers tend to be less
efficient than mains, so matching the sub to the mains means that there must
either be a level mismatch or an attenuator in series with the mains. Then
you're back at the first problem! :-(

2) connect a passive subwoofer in
series with the bookshelf speakers

Same problems as (1) if you get the crossover right. The two are essentially
the same, like comparing series and parallel crossovers.

3) connect a subwoofer with a built in amp

(4) A passive subwoofer with an external amp and active crossover.

I think 1 risks blowing the amp, 2 could affect the sound
quality so I'm leaning towards 3 but this seems a bit of
a waste of the power available from the Cyrus II. Any
opinions?

I wouldn't call a Cyrus 2 a high powered amp by modern standards. 50 wpc?
You can get a clean 100 wpc out of a ca. $100 receiver.