Thanks Alan. What you posted is more or less the plan, and as for using old caps I meant the old poly caps, the green ones, not the black Elcaps. I just keep those for novelty sake 
Thanks for the info about the mid dome testing, I'll definitely do that.
Here's a little teaser..
Sent from my iPhone using Tapatalk
Thanks for the info about the mid dome testing, I'll definitely do that.
Here's a little teaser..
An externally hosted image should be here but it was not working when we last tested it.
Sent from my iPhone using Tapatalk
Hi Alan (and all).
I bought my Celestions in 1976 and carried the boxes around with me for nigh on 20 years before my wife convinced me to part with them.
Alan, in response to some of your earlier questions: yes, the sound is now centered and no I do not have any Gillian Welch albums.
To my latest experimenting. I have now played with the mid-range 4.0uf capacitor together with 3.9ohm, 3.3.ohm and 2.7ohm resistors. You were correct to say that reversing the polarity of the tweeter with the 2.7ohm would restore the twinkle. It did not work so well with the higher resistances.
I also swapped the 4.0uf with the 4.95uf capacitor and went through the 3.9ohm, 3.3ohm and 2.7ohm with both standard and reversed polarity. I'm now back to standard (4.0uf and 3.9ohm) but with one other change...the LPad is now a 62ohm and a 0.51ohm resistor.
In an earlier post you told me if I wanted to hear the Hiquphon at full song to replace the 30.9 resistor with a 62ohm and delete the other resistor entirely. Well, I've got half way and I think I like it. Is this possible? (I didn't remove the other resistor because it's so well connected I felt I might damage something). Can you tell me what the scientific outcome of this value LPad would be?
As a general appraisal I now feel that I am not missing a lot. Obviously most of the really high stuff and/or softly recorded stuff is gone but I feel that I am hearing a 95% spectrum. Also, I think I am getting some sense of depth to the music, as in depth of field. I now think I can detect front instruments and back instruments rather than just a flat plane.
So I did some reading and found that while some people think that depth is attributed to pulling the speakers out from the walls others say it is in the recording.
Well, I'll wait to hear from you before doing any more.
Reggie
I bought my Celestions in 1976 and carried the boxes around with me for nigh on 20 years before my wife convinced me to part with them.
Alan, in response to some of your earlier questions: yes, the sound is now centered and no I do not have any Gillian Welch albums.
To my latest experimenting. I have now played with the mid-range 4.0uf capacitor together with 3.9ohm, 3.3.ohm and 2.7ohm resistors. You were correct to say that reversing the polarity of the tweeter with the 2.7ohm would restore the twinkle. It did not work so well with the higher resistances.
I also swapped the 4.0uf with the 4.95uf capacitor and went through the 3.9ohm, 3.3ohm and 2.7ohm with both standard and reversed polarity. I'm now back to standard (4.0uf and 3.9ohm) but with one other change...the LPad is now a 62ohm and a 0.51ohm resistor.
In an earlier post you told me if I wanted to hear the Hiquphon at full song to replace the 30.9 resistor with a 62ohm and delete the other resistor entirely. Well, I've got half way and I think I like it. Is this possible? (I didn't remove the other resistor because it's so well connected I felt I might damage something). Can you tell me what the scientific outcome of this value LPad would be?
As a general appraisal I now feel that I am not missing a lot. Obviously most of the really high stuff and/or softly recorded stuff is gone but I feel that I am hearing a 95% spectrum. Also, I think I am getting some sense of depth to the music, as in depth of field. I now think I can detect front instruments and back instruments rather than just a flat plane.
So I did some reading and found that while some people think that depth is attributed to pulling the speakers out from the walls others say it is in the recording.
Well, I'll wait to hear from you before doing any more.
Reggie
Replies to Posts #1040 and 1041 , 1042 , 1043.
'ullo Jeffrey ,
very nice vintage Ditton 66 packing boxes !
I suppose they resonate nicely when you have them in the same room as the loudspeakers when music is playing !!
*** *** ***
G'day Denny ,
are you sure that is real Wool ?
It looks like a synthetic fibre to me , by its seeming shape of thread cut , and stiffness ,
but I could be mistaken ...
If it is Sheep's wool , then it should be softer to touch/feel than most synthetic fibres are.
Even if another fibre , it is likely useful , because it looks to be loosely packed ,
that is not too tight for ingress of soundwaves.
It will likely work OK if cut in the shape in my diagram in #935 on Page 94 ,
if that is your intended application.
Alternately , if you want to use it inside a loudspeaker enclosure ,
then cut the fibre sheet to suitable sizes for it to be placed either vertically or horizontally behind the drivers with open-cut edges of the pieces facing the backs of the drivers.
That will allow the best penetration for sound absorption.
*** *** ***
G'day Reggie ,
Good , you have centered image , thus we do not have to consider whether one or more of your inductors may be connected in the opposite winding direction in one of the crossovers than it is in the other crossover.
Believe it or not , if such was the case , there is sufficient Magnetic Field crosstalk for Mutual Addition in one crossover and Mutual Subtraction in the other crossover to cause a different phase response from each loudspeaker , and thereby move a centre image to one side predominately.
On the Laura Marling "A Creature I Don't Know" album , play Track 6.
This song is close to all centre image Mono for both the guitar and the voice ,
and as it is a fairly sparse signal recording it is useful to hear any image drift with , at any time during the song.
Next play Track 5.
That one starts with sparse signal in the centre as Mono , and then some percussion in low frequencies comes in , also basically Mono though filled out a bit.
After 2 minutes an electric guitar enters in the Right Channel , and later another electric guitar enters in the Left Channel ,
thus this track is good for centre image definition across midrange and bass ,
and for mid-bass to low midrange definition for the 500 Hz crossover point ,
and later for the Stereo positioning.
Good thick sounds in this track.
I can clearly understand her diction , all the Lyrics in both tracks 5 and 6 ,
so this Lyrics' intelligibility may be a useful test for deciding the optimum resistance and Polarity connection for the 5kHz crossover point.
Geraint Watkins is a good performer , however a little too smooth for me !
About his song " Easy To Say ' Bon Temps Rouler ' " on his "In A Bad Mood" album ,
I refer you to Clarence Garlow and his song "Bon Ton Roula" , also spelt sometimes as "Bon Ton Roulet" ,
which he recorded twice , the second one being titled " New Bon Ton R...".
Both versions are on YouTube.
I prefer the original , though I quite like the remake also.
Yes , these are rough music , and rough sound vintage recordings ,
however you will hear one of Geraint Watkins' influences !
Did you carry your wife around in one of the Ditton 66 packing cartons ? ...
... and can she decipher the Lyrics from the Laura Marling album ? ...
... a serious question the latter , given the remaining Treble acuity of her hearing in comparison to yours.
Wishbone Ash's "Argus" has been re-released in Japan on CD using the original mix.
I have a new Japanese copy , and prefer that mix to the re-master.
It has a fuller sound.
That cymbals' sound in the song you use for testing is fuller toned ,
and is clearly audible to me in the section you described , however I can clearly hear that cymbal playing in the remaster also.
I'll send you a web address to where you can buy the Japanese CD , and some other good sounding re-issues , including W.Ash's Live Dates Vol 2 , if you like ..?
{ Live Dates 2 has Laurie Wisefield as second guitarist , playing well , and overall the performances are better than on the first Live Dates album where the band is a bit sloppy , etc ...
also better playing of some of the new songs live than on the Studio albums with Wisefield. }
If you prefer the sound with 62 ohm in Parallel with 0.51 ohm in Series ,
then do not worry about such ...
and that may be compensating for a lesser low-treble from your particular samples of the mid-domes ,
as the effect is to slightly increase the output around 5kHz more-so than for higher treble frequencies.
If you want to leave the 0.51 neatly soldered in circuit ,
then go to your Jaycar and buy 4 small , tight closing , Alligator clips.
Use some of your AWG18 hook-up to make two short Jumper leads.
Connect a Jumper lead across each 0.51 ohm to bypass it. Then you will hear only the effect of the 62 ohm resistors.
With jumper leads , and your external crossovers , you can quickly do A/B listening tests.
Another A/B test :-
Buy 4 more Alligator clips and two 62 ohm or 68 ohm resistors , and in 1 watt will be sufficient , because very low current through each in this test if at moderate volume level.
Make two resistor jumpers with each resistor and two Alligator clips.
Connect this 62 or 68 ohm resistor jumper in Parallel with the 62 ohm in your crossover for an quick A/B of 62 ohm versus about 31 ohm or a little higher.
Report all the above here before we proceed any further.
'ullo Jeffrey ,
very nice vintage Ditton 66 packing boxes !
I suppose they resonate nicely when you have them in the same room as the loudspeakers when music is playing !!
*** *** ***
G'day Denny ,
are you sure that is real Wool ?
It looks like a synthetic fibre to me , by its seeming shape of thread cut , and stiffness ,
but I could be mistaken ...
If it is Sheep's wool , then it should be softer to touch/feel than most synthetic fibres are.
Even if another fibre , it is likely useful , because it looks to be loosely packed ,
that is not too tight for ingress of soundwaves.
It will likely work OK if cut in the shape in my diagram in #935 on Page 94 ,
if that is your intended application.
Alternately , if you want to use it inside a loudspeaker enclosure ,
then cut the fibre sheet to suitable sizes for it to be placed either vertically or horizontally behind the drivers with open-cut edges of the pieces facing the backs of the drivers.
That will allow the best penetration for sound absorption.
*** *** ***
G'day Reggie ,
Good , you have centered image , thus we do not have to consider whether one or more of your inductors may be connected in the opposite winding direction in one of the crossovers than it is in the other crossover.
Believe it or not , if such was the case , there is sufficient Magnetic Field crosstalk for Mutual Addition in one crossover and Mutual Subtraction in the other crossover to cause a different phase response from each loudspeaker , and thereby move a centre image to one side predominately.
On the Laura Marling "A Creature I Don't Know" album , play Track 6.
This song is close to all centre image Mono for both the guitar and the voice ,
and as it is a fairly sparse signal recording it is useful to hear any image drift with , at any time during the song.
Next play Track 5.
That one starts with sparse signal in the centre as Mono , and then some percussion in low frequencies comes in , also basically Mono though filled out a bit.
After 2 minutes an electric guitar enters in the Right Channel , and later another electric guitar enters in the Left Channel ,
thus this track is good for centre image definition across midrange and bass ,
and for mid-bass to low midrange definition for the 500 Hz crossover point ,
and later for the Stereo positioning.
Good thick sounds in this track.
I can clearly understand her diction , all the Lyrics in both tracks 5 and 6 ,
so this Lyrics' intelligibility may be a useful test for deciding the optimum resistance and Polarity connection for the 5kHz crossover point.
Geraint Watkins is a good performer , however a little too smooth for me !
About his song " Easy To Say ' Bon Temps Rouler ' " on his "In A Bad Mood" album ,
I refer you to Clarence Garlow and his song "Bon Ton Roula" , also spelt sometimes as "Bon Ton Roulet" ,
which he recorded twice , the second one being titled " New Bon Ton R...".
Both versions are on YouTube.
I prefer the original , though I quite like the remake also.
Yes , these are rough music , and rough sound vintage recordings ,
however you will hear one of Geraint Watkins' influences !
Did you carry your wife around in one of the Ditton 66 packing cartons ? ...
... and can she decipher the Lyrics from the Laura Marling album ? ...
... a serious question the latter , given the remaining Treble acuity of her hearing in comparison to yours.
Wishbone Ash's "Argus" has been re-released in Japan on CD using the original mix.
I have a new Japanese copy , and prefer that mix to the re-master.
It has a fuller sound.
That cymbals' sound in the song you use for testing is fuller toned ,
and is clearly audible to me in the section you described , however I can clearly hear that cymbal playing in the remaster also.
I'll send you a web address to where you can buy the Japanese CD , and some other good sounding re-issues , including W.Ash's Live Dates Vol 2 , if you like ..?
{ Live Dates 2 has Laurie Wisefield as second guitarist , playing well , and overall the performances are better than on the first Live Dates album where the band is a bit sloppy , etc ...
also better playing of some of the new songs live than on the Studio albums with Wisefield. }
If you prefer the sound with 62 ohm in Parallel with 0.51 ohm in Series ,
then do not worry about such ...
and that may be compensating for a lesser low-treble from your particular samples of the mid-domes ,
as the effect is to slightly increase the output around 5kHz more-so than for higher treble frequencies.
If you want to leave the 0.51 neatly soldered in circuit ,
then go to your Jaycar and buy 4 small , tight closing , Alligator clips.
Use some of your AWG18 hook-up to make two short Jumper leads.
Connect a Jumper lead across each 0.51 ohm to bypass it. Then you will hear only the effect of the 62 ohm resistors.
With jumper leads , and your external crossovers , you can quickly do A/B listening tests.
Another A/B test :-
Buy 4 more Alligator clips and two 62 ohm or 68 ohm resistors , and in 1 watt will be sufficient , because very low current through each in this test if at moderate volume level.
Make two resistor jumpers with each resistor and two Alligator clips.
Connect this 62 or 68 ohm resistor jumper in Parallel with the 62 ohm in your crossover for an quick A/B of 62 ohm versus about 31 ohm or a little higher.
Report all the above here before we proceed any further.
Hi ALan. Have done some experimenting but unfortunately my right eardrum has perforated (again) so I will have to wait until it repairs itself (?) before I can resume same. (I seem to remember reading somewhere that there was a fad - for a time - of deliberately perforating ones eardrums because (in some cases) you could actually hear better following said "operation"). Of course, as you suggested, I could always get my wife to be my proxy listener....she could give me sign language as to what she was hearing!
Reggie
Reggie
Hi all,
I have finally found a pair of Celestion MF500s to put into my Celestion Ditton 66s!!
They shipped this morning so I should receive them soon. The seller indicated they measured 7.5ohms.. seems high to me.. so I will measure them myself when I get them. Either way they are in working order and both measure the same so I think that's a good thing.
I have the Seas 19TFF1s installed into my 66s right now - unfortunately they do not mount onto the old mounting hardware. Any ideas for how I can get them to mount without screwing into the front baffle?
Thanks.
I have finally found a pair of Celestion MF500s to put into my Celestion Ditton 66s!!
They shipped this morning so I should receive them soon. The seller indicated they measured 7.5ohms.. seems high to me.. so I will measure them myself when I get them. Either way they are in working order and both measure the same so I think that's a good thing.
I have the Seas 19TFF1s installed into my 66s right now - unfortunately they do not mount onto the old mounting hardware. Any ideas for how I can get them to mount without screwing into the front baffle?
Thanks.
celestion 66 needs Mid-range
I have installed the mids and I also used the crossovers I built for the custom Ditton 44s, except I replaced the necessary parts on the mid filter to suit the 66s mid.
Overall the results are pretty good. The mid and tweeter integrate very well, but the bass seems a bit boomy making the speaker sound heavy. I'm wondering if maybe I wired up something wrong or this is just a result of the speaker sitting directly on a floating floor. I'm planning to install spikes to help with that, and maybe eliminate the issue.
Right now everything is wired in the same phase and I am using the Seas 19TFF1. Should anything be wired out of phase?
Thanks,
Jeffrey
Edit: I also realized I used 30ohms of series resistance with the tweeters. Should I change that?
I have installed the mids and I also used the crossovers I built for the custom Ditton 44s, except I replaced the necessary parts on the mid filter to suit the 66s mid.
Overall the results are pretty good. The mid and tweeter integrate very well, but the bass seems a bit boomy making the speaker sound heavy. I'm wondering if maybe I wired up something wrong or this is just a result of the speaker sitting directly on a floating floor. I'm planning to install spikes to help with that, and maybe eliminate the issue.
Right now everything is wired in the same phase and I am using the Seas 19TFF1. Should anything be wired out of phase?
Thanks,
Jeffrey
Edit: I also realized I used 30ohms of series resistance with the tweeters. Should I change that?
Did we ever cover the idea of something like the cheaper Fostex as a mid range ? They come close to being truly full range . When asked to do less surely they become special ?
I have just been sent some SB acoustics 5 inch from Falcon UK . Is it stretching the idea to included them . The coils are exposed and a work of art . Very good price . Sort of like KEF B110 meets ATC . From about 100 Hz to 5 kHz they are very linear .
Phase of tweeters is very much as you like it . Both are wrong so which version is personal . With DSP is it possible to do it right . I like most people don't get too bothered about it except to to know the possibilities . On the SB and ribbon I will be using out of phase which looks to control the 7 kHz region . In truth I shouldn't use 7 kHz from the SB . Two wrongs might just about make a nearly right . Against all my principles ( paper ) I chose SB as it had the useful defect . The " better " Seas unit was more linear at 7 kHz . That alas meant I had no ideal solution except the better psycho-acoustic effects of high point crossover . I wanted my cake and eat it so went for the mathematical possibility that the SB's error was in fact a friend . I have designed a sealed box and OB crossover . It will be OB to get basic workings established . The ribbons work between 3 and 40 kHz . I will bring them in at 5 kHz ( 7 kHz - 3 dB preferred ) . The SB might be rolled off at 7kHz .
One thing I never understood is ideal distances between drive units . Thanks goodness drive units are not point source . If so we would have comb filter effects . How to set the distance between units is a mystery to me . I have read plenty and know no more having read it . For example 5 inch mid to tweeter distance crossing either 5 or 7 kHz .
I have just been sent some SB acoustics 5 inch from Falcon UK . Is it stretching the idea to included them . The coils are exposed and a work of art . Very good price . Sort of like KEF B110 meets ATC . From about 100 Hz to 5 kHz they are very linear .
Phase of tweeters is very much as you like it . Both are wrong so which version is personal . With DSP is it possible to do it right . I like most people don't get too bothered about it except to to know the possibilities . On the SB and ribbon I will be using out of phase which looks to control the 7 kHz region . In truth I shouldn't use 7 kHz from the SB . Two wrongs might just about make a nearly right . Against all my principles ( paper ) I chose SB as it had the useful defect . The " better " Seas unit was more linear at 7 kHz . That alas meant I had no ideal solution except the better psycho-acoustic effects of high point crossover . I wanted my cake and eat it so went for the mathematical possibility that the SB's error was in fact a friend . I have designed a sealed box and OB crossover . It will be OB to get basic workings established . The ribbons work between 3 and 40 kHz . I will bring them in at 5 kHz ( 7 kHz - 3 dB preferred ) . The SB might be rolled off at 7kHz .
One thing I never understood is ideal distances between drive units . Thanks goodness drive units are not point source . If so we would have comb filter effects . How to set the distance between units is a mystery to me . I have read plenty and know no more having read it . For example 5 inch mid to tweeter distance crossing either 5 or 7 kHz .
Jeffrey ,
I suppose you have now drilled holes in the cabinets for screws to hold the 19TFF1.
I hope you drilled only short length holes , and not long holes to fully through the wood to inside of the cabinet.
You can listen with the tweeter connected in either Polarity ,
however Celestion had it connected in the Negative Polarity ,
but you might prefer it in Positive Polarity, so listen to both options.
Your floating floor will not help the bass , even with spikes under the cabinet ,
if you mean that you have a suspended bouncy floor ... ?
Alternate , if "floating" is only thin acoustic insulation under your floor
to stop sound going to a room underneath , then spikes may help a little ,
but the boomy bass is more likely to be result of where you have the speakers placed in your room.
Keep them away from corners ,
and if too boomy when placed against the back wall then pull them out a bit into the room area.
Connect the 30 ohm resistor in Parallel with the 19TFF1 tweeter ,
not in Series with it , then treble sound should be good.
--- --- ---
Nigel ,
I think the Fostex cone drivers may work with a Celestion 66 crossover ,
but I would need to study their specification plots for Frequency Response AND Impedance versus Frequency
to be able to advise about suitability.
Which Fostex model is it ?
For high frequencies' crossover place the two drivers as close together vertically as possible ,
limited only to the degree that allows sufficient baffle wood in between them
so the baffle is not weak and too resonant between them.
I suppose you have now drilled holes in the cabinets for screws to hold the 19TFF1.
I hope you drilled only short length holes , and not long holes to fully through the wood to inside of the cabinet.
You can listen with the tweeter connected in either Polarity ,
however Celestion had it connected in the Negative Polarity ,
but you might prefer it in Positive Polarity, so listen to both options.
Your floating floor will not help the bass , even with spikes under the cabinet ,
if you mean that you have a suspended bouncy floor ... ?
Alternate , if "floating" is only thin acoustic insulation under your floor
to stop sound going to a room underneath , then spikes may help a little ,
but the boomy bass is more likely to be result of where you have the speakers placed in your room.
Keep them away from corners ,
and if too boomy when placed against the back wall then pull them out a bit into the room area.
Connect the 30 ohm resistor in Parallel with the 19TFF1 tweeter ,
not in Series with it , then treble sound should be good.
--- --- ---
Nigel ,
I think the Fostex cone drivers may work with a Celestion 66 crossover ,
but I would need to study their specification plots for Frequency Response AND Impedance versus Frequency
to be able to advise about suitability.
Which Fostex model is it ?
For high frequencies' crossover place the two drivers as close together vertically as possible ,
limited only to the degree that allows sufficient baffle wood in between them
so the baffle is not weak and too resonant between them.
Thanks Alan, I appreciate your input.
The speakers are actually well out into the room, away from any walls. The floor is indeed like you describe it, it's a mobile home that I live in so the house is held up on 6 big wooden "joists" and basically floats in the air. I may need to get some isolation platforms. I did try swapping the polarity to negative on the tweeter and found this to be more suitable for the overall balance and brilliance of the high frequencies. The bass seemed to behave much better after this as well. I wonder if the tweeter being in phase causes the highs to unbalance, exaggerating the bass. I've heard this before but not due to a phasing issue.
I'll keep the 30ohm resistors in place there, and they are indeed wired in parallel not in series. I learned that the first time I hooked up this crossover
I am going to do more listening tonight but based on what I heard last night with the tweeter polarity reversed it sounded very good. I'll report back after tonight.
Edit:
Almost forgot to mention. I didn't drill any holes - I managed to reuse the original mounting brackets for the HF2000. I checked for air leaks and there are none. I opted to not drill any holes to make sure the cabinet stayed sealed.
Last edited:
Glad the tweeter phasing works . As said both are wrong . The BBC sound seems to favour the so called out of phase option . This produces the recessed mid-band and gives an illusion of greater depth . This wrongness is 2 db typical . Mordaunt Short used the opposite phase and had a sound much loved by Naim owners .
The Fostex I thought of are these .
Fostex FE103En DIY Bass Reflex Bookshelf Speakers / Nearfield Monitors
About phasing . I was given some JPW Sonata speakers to give to a friend . The tweeter was so dull as to sound disconnected . I had to play the tweeters alone to be certain . A series resistor was removed and the phase reversed . That was just about OK . I doped the cones with PVA glue and used some scraps of high grade damping to fill the boxes . Blutak gaskets . After a week I realized they had become rather nice speakers , plenty of reverberant detail . Only when they went I missed them . Some LS3/5A a friend has not automatically better . The Sonata cabinet is nicely made if wondering . I would say 1 star to 5 star at almost no cost . The PVA was a risk . It worked . I have repaired ancient radios with it . All sound better . That wasn't the aim with old radios .
The Fostex I thought of are these .
Fostex FE103En DIY Bass Reflex Bookshelf Speakers / Nearfield Monitors
About phasing . I was given some JPW Sonata speakers to give to a friend . The tweeter was so dull as to sound disconnected . I had to play the tweeters alone to be certain . A series resistor was removed and the phase reversed . That was just about OK . I doped the cones with PVA glue and used some scraps of high grade damping to fill the boxes . Blutak gaskets . After a week I realized they had become rather nice speakers , plenty of reverberant detail . Only when they went I missed them . Some LS3/5A a friend has not automatically better . The Sonata cabinet is nicely made if wondering . I would say 1 star to 5 star at almost no cost . The PVA was a risk . It worked . I have repaired ancient radios with it . All sound better . That wasn't the aim with old radios .
OK I managed to sort out the bass problem. My first thought was the crossover.. But after having it reviewed all is well. Checked every wire. Then I realized that the Ditton 66s I acquired came with a slightly different bass driver - I believe it's the newer version, it had a much larger dust cap. Anyway, I thought maybe this is the culprit, it may have different specs. I threw in the older bass drivers and voila! The bass problem is totally gone. Whew that's a relief, I thought I was going to have to reuse the old crossovers which I didn't want to do, I think it's important the coils have space between them.
Now that they are working properly I'll get some listening in and report back.
Sent from my iPhone using Tapatalk
Now that they are working properly I'll get some listening in and report back.
Sent from my iPhone using Tapatalk
Sorry for the double post here, I'm a little confused about something between version 1 and 2 of the 66.
I've been reading that the crossover in version 2 (the PCC model) is different as in it has a steeper 24dB fourth order linkwitz-riley crossover.. however, when I look at the schematics for both the TBC and PCC model, they look identical.
What I'm trying to get at here is what difference did they make to the crossover with the newer bass driver? Clearly something has to be different, because my handmade crossovers that I took from my custom celestion 44 project use the inductors from the TBC crossover, yet when I plugged it into my 66s which have the newer bass drivers (the bigger dust cap) the bass driver was too loud, pop in the old bass driver as I described above and the bass goes back to normal. Yet, looking at the crossovers, nothing seems different, except one is tidier looking than the other, and the TBC model used a 30uF capacitor on the mid filter vs. a 24uF capacitor, but that shouldn't affect the bass driver. Any ideas?
I've been reading that the crossover in version 2 (the PCC model) is different as in it has a steeper 24dB fourth order linkwitz-riley crossover.. however, when I look at the schematics for both the TBC and PCC model, they look identical.
What I'm trying to get at here is what difference did they make to the crossover with the newer bass driver? Clearly something has to be different, because my handmade crossovers that I took from my custom celestion 44 project use the inductors from the TBC crossover, yet when I plugged it into my 66s which have the newer bass drivers (the bigger dust cap) the bass driver was too loud, pop in the old bass driver as I described above and the bass goes back to normal. Yet, looking at the crossovers, nothing seems different, except one is tidier looking than the other, and the TBC model used a 30uF capacitor on the mid filter vs. a 24uF capacitor, but that shouldn't affect the bass driver. Any ideas?
Hello all, I have a pair of ditton 66 speakers that I got about a year and half ago. The tweeters are burnt out and I have have been able to get two used on ebay $$$$.
They are 4.5 and 4.7ohm readings. I was wondering if that is the standard for the 66's units.
I have been going over all your info on this post and have enjoyed it and also been confused many times. Lol
I have removed my crossovers that are the old style not printed board type.
I ordered new caps and resistors to match the specs of the printed curcuit style crossovers and their values.
I am still kinda wondering if and why I need to wire in the other resistors? The values I got were 1R for the 72uf, 1.5R for other 72uf. Base
1.8R for 24uf line and 2.7 for 4uf. Mid
None for the tweeter side. Does this sound right.
I am using all original ditton speekers.
Really looking forwards to being able to enjoy these speakers.
I am totaly open to any other ideas that might help to improve the sound of these.
I will post pics as I change up the crossovers.
Thanks all
They are 4.5 and 4.7ohm readings. I was wondering if that is the standard for the 66's units.
I have been going over all your info on this post and have enjoyed it and also been confused many times. Lol
I have removed my crossovers that are the old style not printed board type.
I ordered new caps and resistors to match the specs of the printed curcuit style crossovers and their values.
I am still kinda wondering if and why I need to wire in the other resistors? The values I got were 1R for the 72uf, 1.5R for other 72uf. Base
1.8R for 24uf line and 2.7 for 4uf. Mid
None for the tweeter side. Does this sound right.
I am using all original ditton speekers.
Really looking forwards to being able to enjoy these speakers.
I am totaly open to any other ideas that might help to improve the sound of these.
I will post pics as I change up the crossovers.
Thanks all
Jeffery88 - I have only recently aquired 66's and have been wading through this very long thread and other sources before starting any work on my own x-overs.
There is much confusion about 66 models but as far as I have been able to uncover it goes like this:
Series Two is a compleately different design and the ABR is round the back and not on the front baffle. They really should have called this something other than 66 but were perhaps wanting to build on the 66 reputation, it is rare in comparison.
There never was an official MkI and MkII models of the 66. The product was continually updated throughout its life, but some of the changes roughly coincided with the change of the front baffle from the original Black painted (Blackies) to the later veneered baffle (woodies). Owners have started refering to the earlier versions as MkI and the later versions as mkII, not to be confused with the much later Series Two mentioned above. The boundries for changes are blurred and some blackies had some of the later features in them and some of the woodies had earlier ones probably due to cross over in stock of new/old parts. Later Woodies had PCB x-overs but some of the first of these had the older tag board x-overs. Even the tag boards varied, the very first Blackies had air cored inductors which later where wound on to plastic bobins.
Later Bass drivers had a larger dust cap but performed the same I believe.
The mid driver was originaly the MF500 which was later changed to the MD500 of identical appearance. The later mid had a higher power rating and from 50w it went to 80 watts. But the earlier mid had a flatter extended frequency response to above 6kHz and B&O used this in their 5700 model crossed over at 6k. The later MD driver barely makes the 5K crossover point used for the 66's, don't ask me which is the better sounding driver I have read claims for both. The change over point seems to have been roughly when the Woodies came on line but I could'nt swear to it.
The HF2000 tweeter fitted in the woodies with the PCB x-over were type T.2373 and had a pair of caps with a combined value of 6.2 uf in the circuit. The earlier version of the tweeter was T.1637 and used a value of 6.0 uf. In addition, there was a midrange change of capacitance in the x-over from 30uf (for MF500) to 24uf (for MD500). They used different multiples of caps from time to time to create the same total values, appart from that, the x-overs didn't change in terms of schematic from first to last production.
I hope you and others find this helpfull, I think I've got it right, please jump in if anyone knows to the contrary.
There is much confusion about 66 models but as far as I have been able to uncover it goes like this:
Series Two is a compleately different design and the ABR is round the back and not on the front baffle. They really should have called this something other than 66 but were perhaps wanting to build on the 66 reputation, it is rare in comparison.
There never was an official MkI and MkII models of the 66. The product was continually updated throughout its life, but some of the changes roughly coincided with the change of the front baffle from the original Black painted (Blackies) to the later veneered baffle (woodies). Owners have started refering to the earlier versions as MkI and the later versions as mkII, not to be confused with the much later Series Two mentioned above. The boundries for changes are blurred and some blackies had some of the later features in them and some of the woodies had earlier ones probably due to cross over in stock of new/old parts. Later Woodies had PCB x-overs but some of the first of these had the older tag board x-overs. Even the tag boards varied, the very first Blackies had air cored inductors which later where wound on to plastic bobins.
Later Bass drivers had a larger dust cap but performed the same I believe.
The mid driver was originaly the MF500 which was later changed to the MD500 of identical appearance. The later mid had a higher power rating and from 50w it went to 80 watts. But the earlier mid had a flatter extended frequency response to above 6kHz and B&O used this in their 5700 model crossed over at 6k. The later MD driver barely makes the 5K crossover point used for the 66's, don't ask me which is the better sounding driver I have read claims for both. The change over point seems to have been roughly when the Woodies came on line but I could'nt swear to it.
The HF2000 tweeter fitted in the woodies with the PCB x-over were type T.2373 and had a pair of caps with a combined value of 6.2 uf in the circuit. The earlier version of the tweeter was T.1637 and used a value of 6.0 uf. In addition, there was a midrange change of capacitance in the x-over from 30uf (for MF500) to 24uf (for MD500). They used different multiples of caps from time to time to create the same total values, appart from that, the x-overs didn't change in terms of schematic from first to last production.
I hope you and others find this helpfull, I think I've got it right, please jump in if anyone knows to the contrary.
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Silversurfer1 - electronics is not my field so I am only going off what I have read in the thread.
Tweeters - mine both measure 4.7 Ohm so yours are in the right area.
The reason we add the resistors in series with the capacitors is that the original low quality Electrolytic capacitors had a reasonably high resistance. When we replace these with modern Polyprop caps which have a fairly low resistance we are changing the circuit characteristics, so we need to add additional resistors to get back to the original values and have a circuit that functions the same as Celestion intended all be it with better quality parts.
Now the question is, what type of capacitor are your replacements eg the 72uf?
The reason we don't need the resistors in the Tweeter circuit is that Celestion used a better quality film cap there, that has a low resistance similar to the replacement Polyprops we will be using, so resistance will be roughly the same.
I am in the same position as you as far as trying to work out the values of resistors to add and I think you have it right apart from the 2.7 Ohm for the 4uf, I think this should be 3.3 Ohm. The chap that was using 2.7 Ohm had 3.3 Ohm in his other speaker and the difference was to address an inbalance in the output from his two mid range drivers. 3.3 is the correct value normally I believe - you could really do with alan-1-b comming along and confirming this as he seems the authority on this, and I could also do with that point being clarified.
I hope I have put this in a way that makes sense to you.
Tweeters - mine both measure 4.7 Ohm so yours are in the right area.
The reason we add the resistors in series with the capacitors is that the original low quality Electrolytic capacitors had a reasonably high resistance. When we replace these with modern Polyprop caps which have a fairly low resistance we are changing the circuit characteristics, so we need to add additional resistors to get back to the original values and have a circuit that functions the same as Celestion intended all be it with better quality parts.
Now the question is, what type of capacitor are your replacements eg the 72uf?
The reason we don't need the resistors in the Tweeter circuit is that Celestion used a better quality film cap there, that has a low resistance similar to the replacement Polyprops we will be using, so resistance will be roughly the same.
I am in the same position as you as far as trying to work out the values of resistors to add and I think you have it right apart from the 2.7 Ohm for the 4uf, I think this should be 3.3 Ohm. The chap that was using 2.7 Ohm had 3.3 Ohm in his other speaker and the difference was to address an inbalance in the output from his two mid range drivers. 3.3 is the correct value normally I believe - you could really do with alan-1-b comming along and confirming this as he seems the authority on this, and I could also do with that point being clarified.
I hope I have put this in a way that makes sense to you.
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Qwin, Thanks for the response to this post and my questions. It sounds like you have gained a great deal of info on the ditton 66's.
The resistor install makes sens and know I remember. I am using Axon for the 72uf in the form of two 36uf. I think they are close to the solen caps and clarity for mid and hi.
Yes Alan-1-b really knows his stuff and these speakers.
I pulled these figures from a drawing that was posted on page 85 #845. By Denny G. The values were recomended from Allen-1-b but yes maybe some changes were made afer.
That is one reason I posted to see if anyone else found something better.
This is a great post on these speakers and I enjoyed your input to help bring light to the history and changes they have gone through.
The resistor install makes sens and know I remember. I am using Axon for the 72uf in the form of two 36uf. I think they are close to the solen caps and clarity for mid and hi.
Yes Alan-1-b really knows his stuff and these speakers.
I pulled these figures from a drawing that was posted on page 85 #845. By Denny G. The values were recomended from Allen-1-b but yes maybe some changes were made afer.
That is one reason I posted to see if anyone else found something better.
This is a great post on these speakers and I enjoyed your input to help bring light to the history and changes they have gone through.
Silversurfer1 - You could be right about the 2.7 Ohms for the 4uf cap.
So many different conversations and some values are to correct driver inbalance so it gets very tricky to work out what to use.
I thought I would post these measuremants taken from one of the x-overs in my "Blackies" Some folks might find the values of use.
So many different conversations and some values are to correct driver inbalance so it gets very tricky to work out what to use.
I thought I would post these measuremants taken from one of the x-overs in my "Blackies" Some folks might find the values of use.
Hey Qwin, Great lay out of your crossovers! So i noticed that you have the 30uf in the mid. Are you going to replace with the 24?
How close are you to re capping these baby's?
I noticed that the values are not to far out, How do the speakers sound?
Do you know if the tweeters are the original ones?
My caps should be hear soon so looking forwards to being able to enjoy these bad boys.
Have fun
How close are you to re capping these baby's?
I noticed that the values are not to far out, How do the speakers sound?
Do you know if the tweeters are the original ones?
My caps should be hear soon so looking forwards to being able to enjoy these bad boys.
Have fun
Silversurfer1 - Hi I will be going with the 24uf when I build new crossovers. Sticking these back in while I work on them.
Not heard mine or any other 66 for that matter, bought them purely on reputation. If you want to see my progress check out my thread on the Art of Sound linked below.
Renovation of Celestion 66 Studio Monitors
Not heard mine or any other 66 for that matter, bought them purely on reputation. If you want to see my progress check out my thread on the Art of Sound linked below.
Renovation of Celestion 66 Studio Monitors
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