Hello Jonathan I have ditton 25, and I tried to get a crossover schematics from factory but they didn t respond. As my coles tweeters had been blown away, I m trying to get a proper replacement, and it is impossible witihout schematics. I would be very glad if you could sent me the schematics to me on my mail robot@post.t-com.hr
celestion ditton
Also, although it was been asked probably many times, does anybody knows anything about specifications of 12" rola celestion woofer which was used in ditton series. Looks like guitar speaker, but it isn t, great driver,12 inches of pure impregnated paper, goes pretty high and low, I planned to refurbish it and maybe use it two way with some decent tweeter (dynamic or ribbon).
Also, although it was been asked probably many times, does anybody knows anything about specifications of 12" rola celestion woofer which was used in ditton series. Looks like guitar speaker, but it isn t, great driver,12 inches of pure impregnated paper, goes pretty high and low, I planned to refurbish it and maybe use it two way with some decent tweeter (dynamic or ribbon).
celestion ditton
Thanks, that would be nice, and about my 25 I could say that I bought tham for some 200$ a few years ago. I completely remove wires which were realy poor, and replace it with kimber 4pr cable, and immediately improve the overall sound. But the main problem was abr (auxillary bass reflex) which in those days when ditton was constructed (my had inside date of production year 1976) didn t work well and produce dirty bass. Some time ago I removed abr and close the hole with mdf, and bass cleared significantly. Bass expression od that 12" is really impressive when you compare it with a recent production of a bass drivers. About celestion tweeter troels gravesen on his website made a few measurements here
actually coles supertweeter was the worsest performer in trio,and should be removed and replaced with some better driver, maybe planar or ribbon which could perform much better over 10 kHz. I experimented with a planar tweeter and results were promissing, but witihout crossover schematics and detail measurement data for each driver it s impossible to finish the speaker. Or maybe using only bass and ribbon like old mordaunt short (with kef and kelly drivers) speaker.
Thanks, that would be nice, and about my 25 I could say that I bought tham for some 200$ a few years ago. I completely remove wires which were realy poor, and replace it with kimber 4pr cable, and immediately improve the overall sound. But the main problem was abr (auxillary bass reflex) which in those days when ditton was constructed (my had inside date of production year 1976) didn t work well and produce dirty bass. Some time ago I removed abr and close the hole with mdf, and bass cleared significantly. Bass expression od that 12" is really impressive when you compare it with a recent production of a bass drivers. About celestion tweeter troels gravesen on his website made a few measurements here
actually coles supertweeter was the worsest performer in trio,and should be removed and replaced with some better driver, maybe planar or ribbon which could perform much better over 10 kHz. I experimented with a planar tweeter and results were promissing, but witihout crossover schematics and detail measurement data for each driver it s impossible to finish the speaker. Or maybe using only bass and ribbon like old mordaunt short (with kef and kelly drivers) speaker.
Hi, if i'm not wrong the bass driver in the 66 was the same if not near enough to the one in the much smaller 44 if that be the case here are the specs, inc t/s;res [dcr] 4 ohms
fs 22.5 Hz
Sd 511cm 2
Bl 11.5 n/a
sens1w-1m 91.2 dB
Qms 5.32
Qes 0.32
Qts, 0.30
hope this helps btw, its odd isnt it l found these parameters on the audax forum a little while cago, cheers TC
celestion ditton
thanks qwad,those are same drivers which they used in whole series (15,24,44 and 66) and really strange place to find driver specifications of that famous british brand. actually I always thought that speaker had a pretty high sensitivity becouse I use it with my 2a3 set (before I finish an e kit), and it can produce enough music in my listening room.
not some earthquake, but decent, main problem are high frequencies which are really lacking in this combination. maybe some day I refurbish the speaker using this good woofer and combine it with a good tweeter in a two way box.
thanks qwad,those are same drivers which they used in whole series (15,24,44 and 66) and really strange place to find driver specifications of that famous british brand. actually I always thought that speaker had a pretty high sensitivity becouse I use it with my 2a3 set (before I finish an e kit), and it can produce enough music in my listening room.
not some earthquake, but decent, main problem are high frequencies which are really lacking in this combination. maybe some day I refurbish the speaker using this good woofer and combine it with a good tweeter in a two way box.
TD2,tonedef2 said:
In those models, as I remember, auxillary bass reflex membrane (abr) was used as a heimholz resonator to cancellate some inner reflections, and probbably to add some "beef" in bass because when you put 12" bass in relatively small and elegant box you cannot expect an earthquake. Although, as I read in some threads on different websites, they probably later solved problem in ditton 66, and it hadn't that boomy bass. As i recall my crossover had a lc compensation on bass-probably for cutting peak, high and lowpass on mids and II order crossover on tweeter. Tweeter was lousy coles, an it s for sure the worst player in trio, actually worked as a kind of a supertweeter, adding highs in fantastic hf mid-tweeter. Anyway, this dittons were used as a monitor speakers in BBC studios, and surely they are very good value for money, they are very"tube friendly" speakers. Later series resolved the lack of highs, and problem with bass.
Hello,
Thanks for the input, your right about the later 66's like mine, having solved the boomy-ness to the bass like the earlier models. Crossovers are different too, in version .2 a Linkriley setup is used!
But here’s where I get confused the HF2000 and the Coles 4001 are/look completely different? Are they the same?
Also is it the hf2000 tweeter responsible (by design) for my (sometimes) edgy top end?
I really need to frequency sweep the speakers, but I do not have the equipment.....:-(
Do you think a CD and a DB tester would do it? I guess only for an amplitude related spike… :-(
I think its a slight breakup of the rigid plastic cone and i want to test with a thin layer of something like wetlook.....
What you think?
Thanks
Thanks for the input, your right about the later 66's like mine, having solved the boomy-ness to the bass like the earlier models. Crossovers are different too, in version .2 a Linkriley setup is used!
But here’s where I get confused the HF2000 and the Coles 4001 are/look completely different? Are they the same?
Also is it the hf2000 tweeter responsible (by design) for my (sometimes) edgy top end?
I really need to frequency sweep the speakers, but I do not have the equipment.....:-(
Do you think a CD and a DB tester would do it? I guess only for an amplitude related spike… :-(
I think its a slight breakup of the rigid plastic cone and i want to test with a thin layer of something like wetlook.....
What you think?
Thanks
Hm, if we re speaking 'bout same speaker, there 're three similarities, abr, 12" bass and coles supertweeter. This tweeter (if it is same as mine, probbably it is) had plastic cone with rigid wires from coil, which looks like cheap speakers "dum-dum" made in coconut islands. On the other hand, 66 is bigger, surely had different crossover, but I m sure that the highs are problem. As I mentioned before I changed internal wiring, binding posts, and replaced tweeter capacitors with audyn cap (same value), also coles tweeter with cheap gradient planar tweeter(some 40$ pc). The results were promising, becouse speaker get silky highs, much better then original. But evidently, there was problem with upper mids, not critical, but notible, so I needed to work and recalculate the values of the crossover to get much smoother transition.
I stopped experimenting becouse meanwhile I started building audio note an e kit (simple solution for my SET). Probably in future I will try to solve the problem, and put it here
Anyway I suggest that you get behringer 8000 or same calibrated mike,or condenser diy mike and speaker measuring software like audua or arta, than maybe put some planar or ribbon tweeter with some diameter in place of coles tw, than experiment with crossover. My opinion is it can not be worse than before....
cheers,
I stopped experimenting becouse meanwhile I started building audio note an e kit (simple solution for my SET). Probably in future I will try to solve the problem, and put it here
Anyway I suggest that you get behringer 8000 or same calibrated mike,or condenser diy mike and speaker measuring software like audua or arta, than maybe put some planar or ribbon tweeter with some diameter in place of coles tw, than experiment with crossover. My opinion is it can not be worse than before....
cheers,
RE: second series Celestion Ditton 66 Studio Monitors.
My homework shows that this HF2000 tweeters are not Coles made.....that came later..........
Yes the lower end 44's/25's where a different cat, the 44's were closer to the 66's.
So i need a test CD (free?) from somebody that wants to share.
Sorry but refresh my memory...you did this mod work to a set of 33's?
thx
My homework shows that this HF2000 tweeters are not Coles made.....that came later..........
Yes the lower end 44's/25's where a different cat, the 44's were closer to the 66's.
So i need a test CD (free?) from somebody that wants to share.
Sorry but refresh my memory...you did this mod work to a set of 33's?
thx
I have 25 s, made 1976, with 12", two celestion hf 1300 tweeters (actually mid-tweeter), same model which were put in spendor bc1, and coles supertweeter I forgot model (4001?)....
Could you put the picture of your speaker, is it same from my attach?
You have test signal software which allows you to make sample of desired frequency, but you have to connect pc to amplifier, and use decent pc audio card....
Could you put the picture of your speaker, is it same from my attach?
You have test signal software which allows you to make sample of desired frequency, but you have to connect pc to amplifier, and use decent pc audio card....
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