In article , Wally
wrote:
Jim Lesurf wrote:


2) The power amps may have different gains.

They have, but, as I said to Stewart, they each have volume controls,
none is turned up full, and the crossover provides +/-6dB on each band.

But do you now have the same relative effective gains in the bands as
before? If not, then some of the differences can be due to 'tone control'
effects...


3) Your 'crossover' points and slopes may be different to before.

The points are dialled in to match those used by KEF, although I dare
say the active xover has steeper slopes. A steeper slope is generally a
good thing, isn't it?

Not necessarily. :-) The point is that as you go through the crossover
region of the spectrum changing the slopes will alter the resulting
response. For example, using steeper slopes may produce a 'dip'.
Alternatively steeper slopes also means that the phases change in a
different way, so you may get other changes for that reason.


4) The effective gains for the active crossover may now be different
in the various bands.

As I say above, they're settable - even if there are discrepancies
between bands when the gains are set to zero, there's scope to
compensate in any case.

Yes. But if you are doing this 'by ear' to get the result you like, the
result may be that you settle on a different response to before. This then
means that you are using the xover as a tone control and getting
'improvements' from that. Hence having multiple amps may not be giving you
the changes you assume.

[snip]

Indeed, of the passive networks included arrangements to deal with
some detailed aspects of the speakers, the results *might* have been
better in some way. Problem is that we can't tell without a suitable
comparison test.

As I said, the tri-amped set up is the baseline. The way I see it, it's
easier for me to make changes and assess their effects.

That is fair enough. However as I have indicated, people who have *not* yet
spent the money on more power amps, etc, might find it useful to be
cautious and assess what I am saying. There may be a cheaper and easier
route for them. Difficult to say without suitable experiments, etc, in each
individual case.

Slainte,

Jim

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