[quote user="Claus"]Superdario:
Yes - the Jantzen Capacitor are (to my knowledge) considered to be very good for audiophile purposes. Jantzen (no afiliation) specializes in audiophile components - have a look at

Dillen wrote:

I think, it could be fun to see how good a X25/X35 could become if some fairly undrastic modifications,
like these, were tried on it.

Martin,
I do have a pair of S35 (type 6311) that could be used for this purpose: To see what can be done to a mediocre speaker w. some DYI effort and a few new components.

What is your (and others) opinion on using the S35 as the target for this?

Personally I wonder if there might be to many issues w. the S35:
- the Cross Over is primitive
- the Cabinet is “thin”/light (and made from an other type of wood than e.g. S45-2 an others – looks and sounds more like “cigar box” wood…)
- the front is very “loud” when you knock on it
- the woofer has foam surrounds (mine are OK though. I’ve tried to preserve them my "miracle rubber conditioner" - seems to work.)
- the tweeter is (correct?) one of the “least good” B&O have ever used (but it’s a dome though)

Opinions welcome!

Peter,
Measuring the low frequencies is difficult due to room resonances (and I don’t have access to a sound-dead one…).
I’ve made a near field measurement of the woofer – but no important difference is visible (see graph below - colour as before. "Scratch" at 600 Hz is the sound card - again...).
The measuring was done at low level – the enclosure resonances will only be audible at higher SPL. Got to get a mike attenuator...

I’ll be back on the question of M75 vs S45 after I’ve done more serious comparison.
My first impression is that they are alike in many ways and fine speakers (but more bass in M75 of course).
Upgrading M75 will be somewhat more expensive – it’s a much more sophisticated cross over.

Superdario,
No - haven't tried any of Jantzens speaker kits (but I suppose they are of good quality too). 

Login to view image

Claus wrote:

Measuring the low frequencies is difficult due to room resonances (and I don’t have access to a sound-dead one…).

I’ve made a near field measurement of the woofer – but no important difference is visible (see graph below - colour as before. "Scratch" at 600 Hz is the sound card - again...).
The measuring was done at low level – the enclosure resonances will only be audible at higher SPL. Got to get a mike attenuator...

Ear plugs would come in useful here. And neighbours that go on holiday often! 😕

Out of curiosity, what kind of amplifier did you use for the testing here?

I still need a few 'damping' tricks myself, but that's for my system cabinet. It's made out of hollow veneer board, with the Beogram on top of it. When that's playing, it's almost an enormous membrane microphone, so I need to add a ton of dead weight.

Actually, the Beovox S35 is slightly better rated than the X35 and S30(6317).
Even the smaller Beovox S30 (6301) sounds more balanced than the larger S30 (6317).

Martin