SpeakerTalk

[chris]

Hello everyone,

I purchased a pair of KEF C30 speakers 2 weeks ago, yet, one of the cones (SP1206) is not working so I have been looking for a replacement cone. I googled yet could not find anyone selling it. I also asked KEF and they said they don't have any replacement supplies.

Now one of the speakers needs a working cone and I could not find it. I found there are some places online that they sell woofers for KEF C40 speakers instead of C30. I checked out the KEF C series leaflet and found that C30 and C40 speakers both use the same B200 drive units with the same impedence of 8ohms yet their sensivitiy is slightly different, with one being 90db and the other being 91db.

Would the C40 woofer fit my C30 speakers?

Many thanks
Chris

[proffski]

I have not used these but they have a good reputation.
I'll post others if I can still find them.

Link: http://www.wembleyloudspeaker.com/

Others: http://www.audioloudspeakers.co.uk/boultons.shtml
http://www.speaker-repairs.co.uk/shop/repairs.html
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[chris]

[chris]

I found there are some places online that they sell woofers for KEF C40 speakers instead of C30. I checked out the KEF C series leaflet and found that C30 and C40 speakers both use the same B200 drive units with the same impedence of 8ohms yet their sensivitiy is slightly different, with one being 90db and the other being 91db.

KEF C series leaflet: http://www.kef.com/html/fr/explore/about_kef/museum/1980s/C10_C20_C30_C40_C40D_C42_/index.html

Would the C40 woofer fit my C30 speakers?

Many thanks
Chris

[audiolabtower]

At first I would have said the sensitivity figure was for the complete system and the C40 would only be slightly more because it had the bigger box.

However the specs listed show a different SP number for the units, so maybe the same units were selected for sensitivity and then routed to the 30 or 40 cabinet, or maybe there was a more significant difference in the construction to justify the new number, maybe a different impedance voice coil?

[chris]

Thanks for reply.!

[proffski]

The C30 used the B200 (SP1206).
The C40 used the B200 (SP1205).
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

[speakerguru]

An 8" unit in a typical box has a (frontal) response which is higher in the midrange than at LF. This rise would normally be countered in the crossover. If you have 2 x 8" units, then you can use them both at LF (and only one at MF) thereby matching the LF and MF levels at the higher level. However, because the tweeter is the same in both cases, you can't go for the full 3dB increase potentially available. I guess 1dB was a sensible compromise which would give KEF the edge in a shop A-B comparison.

[proffski]

It may also be worth noting that the SP1025 drive units are rated at 3 Ohms!

Links: http://s891.photobucket.com/user/AndyGoloskof/media/KEFSP1205_zpsbc6cd08f.jpg.html?sort=6&o=40#/user/AndyGoloskof/media/KEFSP1205_zpsbc6cd08f.jpg.html?sort=6&o=40&_suid=1403521700483004951188596822509

And for the C30 here: http://s891.photobucket.com/user/AndyGoloskof/media/KEFSP12066OhmsC30_zps104b1f40.jpg.html?sort=6&o=45#/user/AndyGoloskof/media/KEFSP12066OhmsC30_zps104b1f40.jpg.html?sort=6&o=45&_suid=140353311581306763387884769625
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill