Celestion Ditton 25 and 44 Refurbs

[walpurgis]

I take it you are referring to the 5" mid in the 44s.

You could have a look at my recommendation here. It often works'

http://theartofsound.net/forum/showt...222#post742222

[DarrenHW]

I've been listening to these for the last couple of days. One speaker sounds excellent (the one I did first). I've realised there is a problem with the midrange driver in the other one. There is a fair amount of distortion at times. I've taken it out again to have a look and I guess there must be something wrong with the voice coil. It's rubbing when I push it in or out by hand. I'm not sure whether to attempt repairing it, or just look for a replacement on eBay.

Look no further: http://theartofsound.net/forum/showt...F2000-MF500-D5

PM me if you're interested.

[madders]

I take it you are referring to the 5" mid in the 44s.

You could have a look at my recommendation here. It often works'

http://theartofsound.net/forum/showt...222#post742222

Yes the 5" mid - I've attached a couple of pics. I want to try your suggestion with the hair dryer but I can't figure out how to get to the voice coil. I took the three screws out the back, but I can't see how to take it apart without cutting the front.

IMAG1147.jpg IMAG1148.jpg

Also it appears to be rubbing on every side, so maybe it's just totally knackered?

Look no further: http://theartofsound.net/forum/showt...F2000-MF500-D5

PM me if you're interested.

Great thanks! I spent ages looking on eBay earlier! The ones you have for sale look exactly like what I have. If I can't fix it with the hair dryer, I'll PM you. Thanks!

[karma67]

has this driver always done this or has it happened after you did the recap?

[walpurgis]

Yes the 5" mid - I've attached a couple of pics. I want to try your suggestion with the hair dryer but I can't figure out how to get to the voice coil. I took the three screws out the back, but I can't see how to take it apart without cutting the front.

My god. What have you done? Put the screws back and do them up tight and just pray the magnet has not decentralised.

You don't need access to the coil. You just put an elastic band around the coil former which is the tube attached to the back of the cone. Access is through the chassis openings behind the cone.

The rear spider is the corrugated bit behind the cone.

[madders]

My god. What have you done? Put the screws back and do them up tight and just pray the magnet has not decentralised.

You don't need access to the coil. You just put an elastic band around the coil former which is the tube attached to the back of the cone. Access is through the chassis openings behind the cone.

The rear spider is the corrugated bit behind the cone.

Wow it worked! Despite removing the screws (luckily they went back in ok). And I completely misunderstood your instructions. First I pulled it up and heated it, and it wouldn't go back down. Then when I finally realised what you meant with the elastic band, I was pulling it way too tight. Eventually I realised it only needed pulling very slightly. It's still rubbing a little bit, but there is a huge improvement, and no distortion anymore. I'll have another go tomorrow and see if I can get it perfect. I'm amazed I haven't broken it completely!

[madders]

has this driver always done this or has it happened after you did the recap?

I think it must have been the same before the recap. Something didn't sound right, and this must have been the problem. It's very noticeable on piano music, which I didn't listen to before. But I put some on after the recap because I thought it would be good to test the crossover.

[walpurgis]

That's a relief. Find exactly where the coil is rubbing by pressing gently on the coil former all round and moving the cone backwards and forwards a bit until you get the worst contact noise. The elastic band needs to pull exactly in the opposite direction that you are pressing, but not too strongly. Don't overdo the heat either. Just take everything steadily and do it again if not happy. This dodge will normally work, unless the coil is damaged. Either by overheating from too much power causing the coil coating lacquer to bubble and expand or ovality due to ageing or poor manufacture (and yes, I've seen both).

[DarrenHW]

Sounds like your getting there Michael . Are you aware that periodically rotating the bass driver is recommended to compensate for the surrounds sagging under weight possibly causing rubbing of the voice coil?

[madders]

Sounds like your getting there Michael . Are you aware that periodically rotating the bass driver is recommended to compensate for the surrounds sagging under weight possibly causing rubbing of the voice coil?

Hi Darren - yes I've read that a few times, but I didn't look which way round they were before I took them out! I have put them back with the wires at the top, I think it's most likely they were at the bottom before.