SpeakerTalk

[willem-57]

I have a question about the T33A SP1074 8 ohm's which are in my 105.4's. I have seen that kef series C 10/20/30/40 all use T33 with another sp number. But is it possible to screw the frontplate from a T33A SP1074 over on a T33 SP1089 or SP1211 from a C model? The C 10/20/30 and 40 are all 8 ohm speakers like the 105.4. And these C speakers are often for sale for a resonable price.

http://www.kef.com/html/nl/explore/about_kef/museum/1980s/C10_C20_C30_C40_C40D_C42_/index.html

[iso]

As far as I remember T33 SP1074 was 8 ohm non ferrofluid tweeter. Later units mentioned history of Kef driveunits were 4 ohm and if I remember correctly used ferrofluid for cooling. So correct faceplate is not enough.

According to Kef museum SP1089 and SP1087 does exist, but there is no info about these on history of driveunits... so SG might be only source to verify if these model would be suitable replacement.

http://www.kef.com/uploads/files/en/kef_units/A%20History%20of%20Kef%20Drive%20Units%20issue%203.pdf

Best Regards

Kimmo

[willem-57]

Thx for your reaction, i mentioned already that the c series speakers are 8 ohm, so i think that the T33 that these models have are also 8 ohm. Let's hope SpeakerGuru will have the correct answer.

[speakerguru]

AFAIK T33 SP1074 is the only 1" soft dome 8 Ohm tweeter without f/fluid.

I have a vague memory of SP1089 and SP1211 being 4 Ohm f/fluid units made to KEF spec in the Far East, at first by Panasonic, I think. These had centre-terminated braid/tinsel leadouts and were specified as a replacement for the very fragile Audax unit previously used in C series. Later production was by Tonegen who were in turn swallowed up by Foster. There were a lot of problems with f/fluid migration when tweeters were shipped by air at low pressure.

KEF production dept. never tooled up for braid terminated tweeters. (I made the original KM1 braided tweeters by hand and then taught the KEF tweeter section charge hand to make them by hand too, in very small batches)

[willem-57]