Interesting experiment. But did you already install fresh capacitors in the old crossovers, did you recap the penta amps and redo adjustments? Because that should make them sound exactly as new.

A random monacor 3 way crossover will never give the sound B&O intended. And I like to think with the time and recources B&O invest in measuring and perfecting their loudspeakers they gave a fair amount of thought to the crossover design. If a simple crossover were just as good they would have installed one, as it would have saved them lots of cost.

But, if you like the sound, why not? They are your speakers after all. Maybe recap one penta and compare, I wonder what you'll find...

Martin (= die_Bogener) has done some work on the Penta crossovers in the past and is quite an expert. I've listened to his speakers and the result is phenomenal! So yes, apparently a lot of improvement is possible by modifying the Penta crossovers.

Cheers,

Kai

Martin has posted a workshop somewhere in the old forum. Must look it up whether it's still available. He doesn't just change capacitors. There were some other modifications, too. Dillen (another Martin) is also quite experienced on the matter. I was just trying to say that there is improvement possible in the crossover section - something that you have experienced as well.

Greetings,

Kai

This is a typical example of tinkering without any knowledge about crossovers and how they are depending many parameters.

For a start, have you thought about the crossover frequencies? Ever thought about the fact that different impedances of the attached speaker(s) might infuence the crossover frequency?

Have you noticed the difference of height at the outer 2 mids compared to the inner 2 ones. And why these 2 outer mids have an extra "filter" compared with the inner ones?

As you already stated, this your personal opion, which is fine. But don't encourage people to do the same. It's wrong. And that's my opnion and the correct one.

Die Bogener started doing well, but in my opinion failed to do it fully 100% properly.

I would suggest, take the original boards, recap them and make sure that your mids have good surrounds (not sloppy already perishing ones).

I'm having a strange feeling of déjà moo...

The most expensive loudspeakers often have the most complicated and expensive crossovers. It's all in the crossovers! That is why active speakers make sense. The amplifiers + active crossover probably cost nearly the same a high end crossover. 

Did you try restoring the original crossovers or are you merely comparing
a new crossover filter with fresh capacitors to the original with 30 year old ones?

Modern components are fresh but 1uF is still 1uF, 30 years didn't change that and neither Ohms law
nor any other electronic or mechanical calculation has changed either.

What may sound good to you may look awful on paper and sound weird to others.
(There's nothing wrong with that - I like to use Loudness myself).
But we really cannot discuss what sounds good or bad to you.
Give them a sweep and let's see their frequency response with original unrestored, original restored and
your replacement filters.
Then we'll know what you are experiencing and listening to.

Martin