Jim Lesurf wrote:

The 'crossover frequency' specified for most speakers is a fairly
'nominal' value.

Yup, I can appreciate that.


Also, if you are simply splitting the links I assume
the internal LP and HP filters in the speakers are still in the
signal paths. Thus the 'best' setting for your active
crossover/filter may be quite different to that specified for the
speaker when used 'normally'.

No links as such - 3-way speakers with the bass drivers disconnected from
the passive crossovers and wired straight to the bass amp. The remaining
two-way pair are still connected to a single amp, going through the full
3-way crossover (with the LF output open circuit).

I'm thinking of converting to the two-way Kef crossover for splitting the
B110 and T27 (this version has no high-pass element on the B110 cct, since
the B110 is acting as bass and mid in a two-way set up). The B110 is in its
own IB sub-enclosure within the main cabinet. Do you think this is worth
pursuing, or would there be some sort of 'conflict' of B110 roll-off in the
sub-enclosure, compared with the 24dB/octave low-pass that the active
crossover applies to the bass driver?


If you can make up CDs of test sinewaves, etc, and have access to a
reliable sound pressure meter, then it would be interesting to see to
what extent the differences you hear correlate with any changes in
overall frequency response being produced by the active crossover,
differences in gain of the two power amps, and effects of the output
impedances of the amps.

Urrr..., I can make test CDs of sine waves. :-) (With a bit of software I
had on my old computer - would need to find it and reinstall.) Don't have a
sound pressure meter, I'm afraid. I suppose the Cyrus 2 has more gain than
the valve amp. I think their input sensitivities are roughly similar
(200-300mV for full power). The valve amp (20-ish Watts) is set to half
volume, the Cyrus (50W) at about '3', and the gains/cuts on the active
crossover are all set to 0dB. This seems to produce a balanced sound. The
overall volume is controlled by a preamp.

It's all calibrated with the indubitably dubious power of the human
lug-'ole - but it's my lug-'ole, and that's the one that matters. :-) My
impression of the Behringer is that it's essentially flat - without a set of
before and after measurements, I'm assuming that the feeling of better
clarity and improved bass is down to having more power available, and
perhaps splitting bass and mid/top to separate amps.


--
Wally
www.artbywally.com/FiatPandaRally/index.htm
www.wally.myby.co.uk