OK guys, order order, thanks for all the reply to this thread, i now see that there is more to this than i thought,
but to return to the original question, i need to replace the sub woofer, So if i replace the sub with another of the same size and spec it should not affect the sound with regards the enclosure size, yes?.
No. This is the point we have been making. Speakers drive units can be identical in size but have totally different electrical and mechanical characteristics, which determine what type of enclosure they will work in. Without knowing exactly how the old drive units behaved and finding an exact replacement you won't find something that sounds decent in that enclosure, hence the recommendation to have the existing units re-coned.
As to the crossover all i want to do is replace the existng with a more modern item, So which make should i go with?
What make of sub do you reccomend? Pioneer, Bose, Cambridge etc.
ta Gary.
Again, the crossover design will be dependant on the rest of the speaker design parameters so nothing "off the shelf" will work properly, as it won't be designed for the specific speaker. If you are concerned about the crossover, replace the capacitors with modern types of the same value, type and voltage rating as they are the only parts of the crossover which will have deteriorated in reality.
Absolutely, couldn't agree more Kevin.
It is very rare to find a better driver than the one that the cabinet was designed for, if the box is too big or small, you also lose the correct amount of air to support the driver in it's movement, leading to damage as well as poorer sound.
And if you change the crossover to one to fit your new drivers, chances are you'll kill the other devices.
I would suggest pricing the re-cone, then going to your local hi-fi shop, (proper hi-fi, not currys

), and seeing if you can find replacement cabinets that you like for the same sort of money.
If you can, all well & good as (as someone pointed out) the rest of the componants in your speakers may well be getting close to dying too.
If not, you either need to have the re-cone and chance the other bits are ok, or spend a little more on a pair of boxes you do like.
Oh, and for the record, I would avoid B&O.....vastly over-priced Phillips guts, in boxes made by someone that should design sofas for Ikea, that flatly refuse to work properly with ANY other makes of anything, thus forcing you to spend thousands to achieve what you already have for a tenth of the price!!
Apart from the banana phone.......average performance, but
really cool looks
