Help! Ditton 44 speaker suddenly not working....

[zingyzangyzongy]

Hi folks

Be gentle - I have only just joined and I'm not technically-minded electronically, so I may not grasp all your technical terms, but I do have a soldering iron and a multimeter (that I don't fully understand!). I'm not a total div though, and quite handy.:eyebrows:

I have owned my Yamaha CR700 receiver and Ditton 44s for about a year and love their sound, though more on that a bit further down.

Over the last few days have been improving their cabling (inc adding an IEC in/out block and IEC plugs), mainly because the CR takes din speaker connections. I had bought some pretty cheapo cables on eBay as a stop gap, but these were more or less bell wire with plastic plugs on one end, bare on the other and these worked ok with the typical vintage threaded binding posts.

I have now replaced the Dittons' posts with new ones that accept 4mm plugs and soldered up some decent speaker cables. Due to the new cable being too large gauge to attach to the DIN terminals, I made short smaller-diameter trailing leads with DIN on one end and a chunky terminal block on the other to adapt to the heavier cable that I had to the banana plugs. It's as neat as I could expect and works well IMO.

BUT (here it comes)..... when I connected the speakers up for the first time only the right one was producing sound. I swapped the cables at the back and even swapped receivers, but still the same issue. I don't think I shorted any terminals, I have checked the continuity in the cables and speaker sockets and nothing strange. I even used the multimeter between the speaker cone terminals and the speaker sockets and this showed continuity (though I am aware that I'm not sure exactly what I am looking for here). Obviously I have made a few changes, but I can't figure out what is going on using my simple process of elimination so far. Although it may prove embarrassing for me, a 'noob', as the 12-year-olds say, I'm sort of hoping I have overlooked something stupidly obvious (and therefore a cheap solution!).

The amp and speakers haven't given me any problems before, but I am concerned that I may have blown something in the crossover. There is no obvious sign. Is this likely? I am also watching a crossover on eBay that is the same sort of age and appearance, but I don't know if it is possible to replace only one as opposed to a pair, even if I did buy it. :scratch:

I have also wondered about the midrange on these too - it has seemed a bit flabby and bloated at times, but not terrible, though it has made me wonder about replacement of the caps that I read about so often. Could I do it myself?

Many thanks for any help given here. I'll post some nice pics or something later to help offset your efforts :)

Best
Pim

[Light Dependant Resistor]

Hi folks

Be gentle - I have only just joined and I'm not technically-minded electronically, so I may not grasp all your technical terms, but I do have a soldering iron and a multimeter (that I don't fully understand!). I'm not a total div though, and quite handy.:eyebrows:

I have owned my Yamaha CR700 receiver and Ditton 44s for about a year and love their sound, though more on that a bit further down.

Over the last few days have been improving their cabling (inc adding an IEC in/out block and IEC plugs), mainly because the CR takes din speaker connections. I had bought some pretty cheapo cables on eBay as a stop gap, but these were more or less bell wire with plastic plugs on one end, bare on the other and these worked ok with the typical vintage threaded binding posts.

I have now replaced the Dittons' posts with new ones that accept 4mm plugs and soldered up some decent speaker cables. Due to the new cable being too large gauge to attach to the DIN terminals, I made short smaller-diameter trailing leads with DIN on one end and a chunky terminal block on the other to adapt to the heavier cable that I had to the banana plugs. It's as neat as I could expect and works well IMO.

BUT (here it comes)..... when I connected the speakers up for the first time only the right one was producing sound. I swapped the cables at the back and even swapped receivers, but still the same issue. I don't think I shorted any terminals, I have checked the continuity in the cables and speaker sockets and nothing strange. I even used the multimeter between the speaker cone terminals and the speaker sockets and this showed continuity (though I am aware that I'm not sure exactly what I am looking for here). Obviously I have made a few changes, but I can't figure out what is going on using my simple process of elimination so far. Although it may prove embarrassing for me, a 'noob', as the 12-year-olds say, I'm sort of hoping I have overlooked something stupidly obvious (and therefore a cheap solution!).

The amp and speakers haven't given me any problems before, but I am concerned that I may have blown something in the crossover. There is no obvious sign. Is this likely? I am also watching a crossover on eBay that is the same sort of age and appearance, but I don't know if it is possible to replace only one as opposed to a pair, even if I did buy it. :scratch:

I have also wondered about the midrange on these too - it has seemed a bit flabby and bloated at times, but not terrible, though it has made me wonder about replacement of the caps that I read about so often. Could I do it myself?

Many thanks for any help given here. I'll post some nice pics or something later to help offset your efforts :)

Best
Pim

Hi
With your multimeter set to ohms.Amplifier off Check not just continuity of cables connecting
but what measures between the black and red terminals on the speaker. Celestions will
likely measure about 6 ohms.

If the speakers measure much higher or meter shows open circuit there is indeed a fault
to find, and with substituting replacement parts, its easy to leave a wire off. Try another
speaker on the channel not working... do you get sound ?

If speaker measures OK at about 6 ohms, and can be anywhere between 4 and 8 ohms
then you would presume fault is in cabling or perhaps the amplifier.
You can test the amp channel not going with another speaker. Or with music
at very low volume and your meter set for AC volts you should get readings
corresponding with the music peaks measuring across the red and black
speaker terminals. Your meter is a very high impedance device, and will not
load the relationship of amp to speaker - allowing measurements.
best unless you have a good meter like a Fluke to not go to ohms
when music is playing, good meters will handle this contradiction
of having voltages occurring, but others may not.

If you have an amplifier fault, on one channel with the amp off
and power cord disconnected check fuses if any that the amplifier has.

At this point put the kettle on for tea/ coffee hot chocolate grab a chocolate biscuit a piece of paper
and draw what your work substituting parts involved. Make the top of the page a line
showing positive and the bottom negative then speaker in between, the answer
may appear to you

Hopefully you have just made a simple error, standing by to assist further.

Cheers / Chris

[DarrenHW]

Hi Pim,

With the speaker that is not working try removing the new binding posts from the mounting plate that is screwed into the cabinet, reconnect the posts to the internal wiring (hanging out of the cabinet) and try them again. I have had issues with short circuits across the mounting plate with certain binding posts. If this works remove the insulators (washers) from the original binding posts and install these either side of the mounting plate (as they were originally installed) and refit the new posts. If you have no joy with this posting some photo's may help.

Good luck.

[zingyzangyzongy]

Thanks Chris and Darren.

As soon as I have got up and running today I will try all your suggestions. Here's hoping.....:)

[zingyzangyzongy]

I was just about to attempt Chris' in-depth approach to tracking down the problem when I decided that Darren's suggestion was quite simple to undertake, so I'd try that first. I unscrewed the banana sockets, bypassing the mounting plate and would you believe it that was the solution! :D

The rear of the sockets was shorting through the metal Ditton badge after all. I didn't realise those washers insulated - I assumed they were metal. I am very grateful to you both for helping - I was becoming increasingly concerned I had blown something somewhere and things were going to become expensive.:rolleyes:

I haven't had a chance to investigate properly why the other speaker isn't doing the same - I'm pretty sure the original washers are a smaller diameter than the new socket thread, so I couldn't fit them :scratch: Are there any decent DIY workarounds? A circle of insulating tape or similar?

Thanks again ;-)

Pim

[Light Dependant Resistor]

Hi Pim
Ah the properties of insulation ! , think how long you are going to
enjoy the Celestion speakers, and appropriately make a new plate
arrangement for them that is going to last and last, and look good.
There is lots of choice online for parts that will be high quality
and at the same time well insulated. But tape will do until you
can repair them more fully. Just keep those wire apart.

Cheers / Chris


.

[DarrenHW]

Glad it worked! I had exactly the same problem, one speaker worked the other didn't, after I'd re-wired and recapped a pair of 44's. Took me hours checking my work and swapping components, eventually I tried a different pair of binding posts out of sheer desperation as I had nothing left to try:doh:. I've got a couple of pairs of 44's that have been modded so feel free to drop me a PM if you ever need any spare parts as I still have all the original components. If your going to keep your 44's Ken's thread is a wealth of information and well worth a read http://theartofsound.net/forum/showthread.php?31916-Renovation-of-Celestion-66-Studio-Monitors&highlight=ditton, it's on the 66's but most of it applies to the 44's. I initially followed the DIYAudio reworking but IMO Ken's is a far better arrangement. Enjoy your 44's and welcome to the club :).

[karma67]

Glad it worked! I had exactly the same problem, one speaker worked the other didn't, after I'd re-wired and recapped a pair of 44's. Took me hours checking my work and swapping components, eventually I tried a different pair of binding posts out of sheer desperation as I had nothing left.

yep me too! lol
i used a small strip of insulation tape wrapped around the post where it passes through the metal ditton plate.

[DarrenHW]

Then it seems were all in good company! I've just taken delivery of a pair of Beovox 5700's (thanks to Geoff's eagle eye's) so my next project is to swap the D5 mid for the MD500 as used in the 66's, I've only had a quick listen to the 5700's to make sure everything's working and even in their current condition the performance is very encouraging!

[karma67]

that should be interesting,let me know how they go please,what brand of polys did you use for your (mid/hf) crossovers? i went with ansar supersound.

[awkwardbydesign]

Did you unpack both binding posts at the same time? With insulating washers, often one is flat and the other is "top hat" shaped. If you put two flat ones together there would be no insulating sleeve for the metal post.

[walpurgis]

Yes. You have to be wary with Celestion terminal plates. The sticker with info on is aluminium and can short the terminals. I put modern banana sockets into a pair of Ditton 15s whilst doing a recap and had to be rather careful.

[karma67]

one of mine stopped working after my amp blew,you can imagine my face! the drivers tested fine but wouldn't work when connected to the binding posts,everything tested fine up to the posts,then i remembered that when enlarging the holes in the plastic cup i noticed the name plate was metal. bingo!

[DarrenHW]

that should be interesting,let me know how they go please,what brand of polys did you use for your (mid/hf) crossovers? i went with ansar supersound.

I'd be happy to share my findings, I started a thread quite a while ago which I need to update. I'm currently using Jantzen Cross Caps (I do have 1 Clarity Cap in the HF as I bought it with the SEAS and coils from Ken) as I've recapped 6 pairs of speakers over the last 12 months and Cross Caps are cheap as chips. Once the configuration is finalised I'll probably try some Ansars too.

[zingyzangyzongy]

Thanks everyone for your helpful replies and interest - I will definitely have a look at the 66 thread.

I didn't use the cheapo option of insulating tape ;-), but managed to fit the original tiny but effective Celestion insulating washers which thankfully just fit over my banana sockets' shafts. Now there is no more distortion or flickering light on my CR700! Glad I got away with it.

Cheers!:cool: