Here's a shot of one of them wired up with cabs unfinished:
It sounds excellent. I am picking up the other cabinet tonight and will be wiring that one up to have a listen in stereo. Can't wait.
An externally hosted image should be here but it was not working when we last tested it.
It sounds excellent. I am picking up the other cabinet tonight and will be wiring that one up to have a listen in stereo. Can't wait.
Took me 4 hours, but I got the other one wired up!
An externally hosted image should be here but it was not working when we last tested it.
Baffle treatment
Hi Jeffrey ,
the cabinets with drivers in look good.
Before you consider whether to stain finish or varnish the wood surfaces
there is one thing you can do to improve both the Tone further towards transparency ,
and the Imaging ability for Stereo perspective - width/depth.
That is , cover the front baffle panel with natural Wool Felt.
Wool Felt can be bought in several grades of Density , and in at least 3 colours ,
though the most common are White and two shades of Grey.
Grey will match the drivers' cones.
I will advise on the optimum Density to buy if you decide to proceed with.
It needs to be a soft grade ,
and you will need a Thickness that is at least equal to the height the mid-cone is raised out from the front of the baffle ,
and better will be if equal to the height the woofer front rim is out from the baffle.
For Area , cover most of the baffle ,
that is leave the rounded edges exposed , but cover from the beginning of the flat area all around the top and sides ,
and down to at least the top half of around the woofer.
I would cover round to the 3/4 points adjacent to the lower two screw fixings of the woofer ,
because that would be visually pleasing.
Obviously , cut holes for the drivers so they are not covered.
The felt must have a rough surface facing outwards , not a smooth sealed finish surface ,
because a sealed smooth surface will reflect a part of the frequency bandwidth ,
where-as an open felt fibre surface will absorb the portion of the sound waves that cause the problems.
The purpose is to reduce sound wave Reflections and Diffraction of sound from the hard edges of the driver chassis/s and the hard front baffle ,
because those cause non-linear addition and subtraction effects across the midrange and lower treble , where the drivers are hemispherically directional.
The lower midrange and bass are less affected because of their longer wavelenghts in proportion to the dimensions of the rims of the drivers and the width of the baffle.
This was done by some manufacturers of quality loudspeakers years ago , including notably Acoustic Research ,
and it is still done by a few high-end manufacturers ,
however none in the lower priced brands simply because of cost.
Most buyers have never heard the difference , and cannot hear it clearly in a crowded showroom in a shop ,
so they will not pay for it , however it can be heard clearly at home.
Hi Jeffrey ,
the cabinets with drivers in look good.
Before you consider whether to stain finish or varnish the wood surfaces
there is one thing you can do to improve both the Tone further towards transparency ,
and the Imaging ability for Stereo perspective - width/depth.
That is , cover the front baffle panel with natural Wool Felt.
Wool Felt can be bought in several grades of Density , and in at least 3 colours ,
though the most common are White and two shades of Grey.
Grey will match the drivers' cones.
I will advise on the optimum Density to buy if you decide to proceed with.
It needs to be a soft grade ,
and you will need a Thickness that is at least equal to the height the mid-cone is raised out from the front of the baffle ,
and better will be if equal to the height the woofer front rim is out from the baffle.
For Area , cover most of the baffle ,
that is leave the rounded edges exposed , but cover from the beginning of the flat area all around the top and sides ,
and down to at least the top half of around the woofer.
I would cover round to the 3/4 points adjacent to the lower two screw fixings of the woofer ,
because that would be visually pleasing.
Obviously , cut holes for the drivers so they are not covered.
The felt must have a rough surface facing outwards , not a smooth sealed finish surface ,
because a sealed smooth surface will reflect a part of the frequency bandwidth ,
where-as an open felt fibre surface will absorb the portion of the sound waves that cause the problems.
The purpose is to reduce sound wave Reflections and Diffraction of sound from the hard edges of the driver chassis/s and the hard front baffle ,
because those cause non-linear addition and subtraction effects across the midrange and lower treble , where the drivers are hemispherically directional.
The lower midrange and bass are less affected because of their longer wavelenghts in proportion to the dimensions of the rims of the drivers and the width of the baffle.
This was done by some manufacturers of quality loudspeakers years ago , including notably Acoustic Research ,
and it is still done by a few high-end manufacturers ,
however none in the lower priced brands simply because of cost.
Most buyers have never heard the difference , and cannot hear it clearly in a crowded showroom in a shop ,
so they will not pay for it , however it can be heard clearly at home.
Last edited:
Those speakers look amazing! I bet they sound extremely well.
I bought dittons 44 as well and going to do some small project.
wanted to follow and clone Istari_knight project:
Celestion Ditton 44 Refurb [Tweeter repair / Cab Resto etc] - pink fish media
but use Vifa XT19TD00-04 ¾" Tweeter instead of Seas 19TFF
data sheets for both can be found there:
H0737-08 19TFF 1
http://www.essentialaudio.com.au/pdf/vifa/Vifa_XT19TD00-04.pdf
Istari_knight in his project revised crossover:
Celestion Ditton 44 Crossover [SEAS Revision] | Flickr - Photo Sharing!
I would really appreciate if someone more technical could help mi with accomodating Vifa tweeter into dittons 44, I really wanted to clone Istari_knight project with minimal changes due to different tweeter- I really would like to use vifa ( because its simply more flat and got wider frec responce) The problem is that as said before I have no idea what soever about crossover calculations etc. I will be fine with soldering but have no idea what different part should use to put xt19 in with good result.
Anyone could help
?
ps. sorry for bad english as well
I bought dittons 44 as well and going to do some small project.
wanted to follow and clone Istari_knight project:
Celestion Ditton 44 Refurb [Tweeter repair / Cab Resto etc] - pink fish media
but use Vifa XT19TD00-04 ¾" Tweeter instead of Seas 19TFF
data sheets for both can be found there:
H0737-08 19TFF 1
http://www.essentialaudio.com.au/pdf/vifa/Vifa_XT19TD00-04.pdf
Istari_knight in his project revised crossover:
Celestion Ditton 44 Crossover [SEAS Revision] | Flickr - Photo Sharing!
I would really appreciate if someone more technical could help mi with accomodating Vifa tweeter into dittons 44, I really wanted to clone Istari_knight project with minimal changes due to different tweeter- I really would like to use vifa ( because its simply more flat and got wider frec responce) The problem is that as said before I have no idea what soever about crossover calculations etc. I will be fine with soldering but have no idea what different part should use to put xt19 in with good result.
Anyone could help
? ps. sorry for bad english as well
Alan, for my 44 TBC bass section, I am looking to replace the iron core inductors with air core in the values 3.3mH and 2.0mH. I can't afford the very lowest DCR inductors, and nor do I imagine that they are really necessary. Would 1mm wire be sufficient to yield a major improvement in your opinion? That would produce 3.3mH with 1.04 Ohms and 2.0mH with 0.8 Ohms. The ones I'm looking at are Jantzens, like all of the caps in my crossover (your advice I believe! )
)Not that Vifa tweeter !
mixMZ ,
I strongly recommend that you do not use the Vifa XT19TD00-04 ,
because whilst it might appear superficially to have a flatter and wider frequency response ,
it does not have as much of the part of the Treble Bandwidth needed to make the Celestion 44 an extended treble loudspeaker.
That Vifa is intended for use in a fairly high Sensitivity 2-way loudspeaker.
You do not need its 89dB Sensitivity for the 44 , because it will be too bright and need attenuation.
The SEAS 19TFF1 at 87dB does not need attenuation , unless you want to get a traditional rolled off treble sound.
See also , the Vifa rolls off above 10kHz , whilst the SEAS extends to beyond 16kHz.
The lower treble end of the bandwidth of the Vifa is not needed ,
because the 44's mid-cone's response extends to there ,
so use the SEAS tweeter.
Istari_knight stated :-
"Some clever chap over on diyaudio has calculated the necessary changes to the crossover making the Seas a proper replacement instead of a bodge."
-
Well , whoever that "clever chap" is , it is not me !
I have been recommending the SEAS as a replacement for the Celestion HF2000 ,
and I did recommend the Hiquphon OW1 as a higher quality alternate ,
BUT I did NOT recommend a resistive L-Pad of 1 ohm + 12 ohm for use with either.
1 ohm with 12 ohm will cause the wrong Impedance load for the crossover tweeter filter for both those tweeters.
Also , I did NOT recommend 3.9uF + 10uF as ideal.
3.9uF is better used with 12uF , and with a different L-Pad , or with no L-Pad but only a Parallel connected resistor.
An L-Pad will cause the tweeter output to be lower than the mid-cone output ,
so use an L-Pad only if you want the Vintage type Celestion 44 sound of slightly rolled off treble ,
and not a modern sound of flat response through midrange and treble.
Better is to use 3.6uF + 11uF and a 27 ohm resistor connected in Parallel with the tweeter.
3.9uF + 10uF is a compromise for people who cannot easily obtain 3.6uF + 11uF.
3.9 + 10 will not yield a flat response , but will cause a small hump a little above 5kHz.
Also , I do not recommend Electrolytic capacitors for the midrange and woofer filters.
Better sound can be got from Celestion 44 than Istari_knight has to date.
Go to this thread:-
Crossover nightmare!!!!!!!
started by:-
lorienblack
and read past the first few pages until you find where I start advising about capacitor upgrades for the crossover ,
and you will find there what is better to use.
Also , I recommend you do NOT use Isopropyl or any type of Alcohol to clean the rubber surrounds of vintage drivers ,
which Istari_knight has done ,
because alcohols can dry the rubber too much and it may later crack.
Leave any old adhesive there on the rubber.
For other substances on the rubber , use a dilute detergent with warm , not hot , water to clean gently ,
then use a warm water soaked cloth to wipe off all the remaining detergent - several times.
Do not leave any detergent to dry on the rubber.
You have not included a Flag under your user-name.
Which Nation are you in { so I can know whether you can buy 3.6uF and 11uF caps easily } ?
*** *** ***
I have Copied LucasAdamson's query and Pasted it in the "Crossover nightmare!!!!!!!" thread and replied to it there ,
because there it follows earlier discussion in that thread about upgrading the Inductors.
mixMZ ,
I strongly recommend that you do not use the Vifa XT19TD00-04 ,
because whilst it might appear superficially to have a flatter and wider frequency response ,
it does not have as much of the part of the Treble Bandwidth needed to make the Celestion 44 an extended treble loudspeaker.
That Vifa is intended for use in a fairly high Sensitivity 2-way loudspeaker.
You do not need its 89dB Sensitivity for the 44 , because it will be too bright and need attenuation.
The SEAS 19TFF1 at 87dB does not need attenuation , unless you want to get a traditional rolled off treble sound.
See also , the Vifa rolls off above 10kHz , whilst the SEAS extends to beyond 16kHz.
The lower treble end of the bandwidth of the Vifa is not needed ,
because the 44's mid-cone's response extends to there ,
so use the SEAS tweeter.
Istari_knight stated :-
"Some clever chap over on diyaudio has calculated the necessary changes to the crossover making the Seas a proper replacement instead of a bodge."
-
Well , whoever that "clever chap" is , it is not me !
I have been recommending the SEAS as a replacement for the Celestion HF2000 ,
and I did recommend the Hiquphon OW1 as a higher quality alternate ,
BUT I did NOT recommend a resistive L-Pad of 1 ohm + 12 ohm for use with either.
1 ohm with 12 ohm will cause the wrong Impedance load for the crossover tweeter filter for both those tweeters.
Also , I did NOT recommend 3.9uF + 10uF as ideal.
3.9uF is better used with 12uF , and with a different L-Pad , or with no L-Pad but only a Parallel connected resistor.
An L-Pad will cause the tweeter output to be lower than the mid-cone output ,
so use an L-Pad only if you want the Vintage type Celestion 44 sound of slightly rolled off treble ,
and not a modern sound of flat response through midrange and treble.
Better is to use 3.6uF + 11uF and a 27 ohm resistor connected in Parallel with the tweeter.
3.9uF + 10uF is a compromise for people who cannot easily obtain 3.6uF + 11uF.
3.9 + 10 will not yield a flat response , but will cause a small hump a little above 5kHz.
Also , I do not recommend Electrolytic capacitors for the midrange and woofer filters.
Better sound can be got from Celestion 44 than Istari_knight has to date.
Go to this thread:-
Crossover nightmare!!!!!!!
started by:-
lorienblack
and read past the first few pages until you find where I start advising about capacitor upgrades for the crossover ,
and you will find there what is better to use.
Also , I recommend you do NOT use Isopropyl or any type of Alcohol to clean the rubber surrounds of vintage drivers ,
which Istari_knight has done ,
because alcohols can dry the rubber too much and it may later crack.
Leave any old adhesive there on the rubber.
For other substances on the rubber , use a dilute detergent with warm , not hot , water to clean gently ,
then use a warm water soaked cloth to wipe off all the remaining detergent - several times.
Do not leave any detergent to dry on the rubber.
You have not included a Flag under your user-name.
Which Nation are you in { so I can know whether you can buy 3.6uF and 11uF caps easily } ?
*** *** ***
I have Copied LucasAdamson's query and Pasted it in the "Crossover nightmare!!!!!!!" thread and replied to it there ,
because there it follows earlier discussion in that thread about upgrading the Inductors.
Last edited:
Could the "clever chap" have been me??? I have used 3.9uF and 10uF in the treble section, but all of it on the advice, or near the advice of you Alan. The circuit seems to be beautifully balanced as it is. I only want to remove the iron core inductors now, to se if an improvement can be made, which is just tinkering, as they sound great right now. (I am also going to build new cabinets - current idea is to remove mid & treble and put them in bamboo Ikea bowl cabinets.)
My circuit as it is now:
Sorry for small file, but I'm having trouble uploading to the gallery.
My circuit as it is now:
Sorry for small file, but I'm having trouble uploading to the gallery.
Last edited:
mistake in #88 circuit diagram ! + a Cabinet idea .
'ullo Lucas ,
I wonder if you are a "clever chap" , because there is a mistake in your Circuit Diagram ...
... and I hope it is only in the diagram , and you do not have your crossover connected completely like that ...
I refer to the Input of the Woofer filter where you have L5 as 2.0mH ,
and the central Inductor L4 where you have 3.3mH ...
ahem , 3.3mH should be at the Input to the filter , and 2.0mH or 2.2mH should be in the central position.
It may sound a bit unusual with the Inductors connected as you have drawn ...
but perhaps not ... comments ?
Also , it seems you have indicated there is a 15R resistor in your Tweeter filter ,
though you have not drawn it down in Parallel with the output as it will have to be in Parallel with the SEAS tweeter there ...
... do you have a 15R Parallel leg there ?
I see the Audiophiler 10uF cap ... the presumed Made-In-China Mundorf ...
well , if the sound is as good as you state , it does not matter where the cap is made ...
and the Chinese have now the knowledge and ability make good audio quality caps if they want to.
The bump in the tweeter frequency response with 3.9uF and 10uF may be very small in magnitude ,
and in combination with how the tweeter output adds with that particular mid-cone's output around 5kHz
there may be a serendipitous co-incidence of almost perfection ... at least on whatever Vertical Axis you use for critical listening.
To other readers here I note as follows:
the Vertical listening Axis can be changed by increasing the 2.7 ohm resistor in Series with the 6.2uF cap at the output of the midrange filter to 3.3 ohm or 3.9 ohm ,
and I recommend no larger or a notch will develop in the upper midrange output.
Lucas ,
instead of a new enclosure , use the existing enclosure for the woofer ,
but turn it up-side-down.
That will raise the woofer so that the lower midrange output from it can integrate better with that from the mid-cone
after you put the mid-cone in a separate enclosure { with the tweeter } on top of the woofer enclosure.
The other integration modification is to decrease the midrange Input cap from 33uF down to 27uF ,
however again , that will be a Vertical listening Axis dependent tweek ,
and 30uF may work better , or even 25uF dependant on Vertical listening height.
Now , correct your Circuit Diagram , and Post it here for readers of this thread ,
and also in the Crossover nightmare!!!!!!! thread so we can continue discussion about your intended Inductor upgrades there with a correct Diagram to refer to.
As for the "clever chap" who worked out how to integrate the SEAS 19TFF1 tweeter into vintage Celestion loudspeakers ...
... well , he could be a Legend now ... a Composite of which-ever people who have told the story and tried who-evers' ideas !
Such things do happen , but if I am included I want my contributions to be remembered as I stated them and not with the wrong combinations of resistors , etc ...
and as should yours be , if based on your listening reports about your variations' modifications.
'ullo Lucas ,
I wonder if you are a "clever chap" , because there is a mistake in your Circuit Diagram ...
... and I hope it is only in the diagram , and you do not have your crossover connected completely like that ...
I refer to the Input of the Woofer filter where you have L5 as 2.0mH ,
and the central Inductor L4 where you have 3.3mH ...
ahem , 3.3mH should be at the Input to the filter , and 2.0mH or 2.2mH should be in the central position.
It may sound a bit unusual with the Inductors connected as you have drawn ...
but perhaps not ... comments ?
Also , it seems you have indicated there is a 15R resistor in your Tweeter filter ,
though you have not drawn it down in Parallel with the output as it will have to be in Parallel with the SEAS tweeter there ...
... do you have a 15R Parallel leg there ?
I see the Audiophiler 10uF cap ... the presumed Made-In-China Mundorf ...
well , if the sound is as good as you state , it does not matter where the cap is made ...
and the Chinese have now the knowledge and ability make good audio quality caps if they want to.
The bump in the tweeter frequency response with 3.9uF and 10uF may be very small in magnitude ,
and in combination with how the tweeter output adds with that particular mid-cone's output around 5kHz
there may be a serendipitous co-incidence of almost perfection ... at least on whatever Vertical Axis you use for critical listening.
To other readers here I note as follows:
the Vertical listening Axis can be changed by increasing the 2.7 ohm resistor in Series with the 6.2uF cap at the output of the midrange filter to 3.3 ohm or 3.9 ohm ,
and I recommend no larger or a notch will develop in the upper midrange output.
Lucas ,
instead of a new enclosure , use the existing enclosure for the woofer ,
but turn it up-side-down.
That will raise the woofer so that the lower midrange output from it can integrate better with that from the mid-cone
after you put the mid-cone in a separate enclosure { with the tweeter } on top of the woofer enclosure.
The other integration modification is to decrease the midrange Input cap from 33uF down to 27uF ,
however again , that will be a Vertical listening Axis dependent tweek ,
and 30uF may work better , or even 25uF dependant on Vertical listening height.
Now , correct your Circuit Diagram , and Post it here for readers of this thread ,
and also in the Crossover nightmare!!!!!!! thread so we can continue discussion about your intended Inductor upgrades there with a correct Diagram to refer to.
As for the "clever chap" who worked out how to integrate the SEAS 19TFF1 tweeter into vintage Celestion loudspeakers ...
... well , he could be a Legend now ... a Composite of which-ever people who have told the story and tried who-evers' ideas !
Such things do happen , but if I am included I want my contributions to be remembered as I stated them and not with the wrong combinations of resistors , etc ...
and as should yours be , if based on your listening reports about your variations' modifications.
Last edited:
I don't know if the bass inductors are that way around, as I haven't measured them - I merely took those values from a pre-existing 44 schematic. Mine are in the standard order.
The 15 ohm resistor is a standard 44 component in the standard position, and yes it bridges the + to - , so is indeed in parallel with the Seas tweeter. I included it in the schematic a little late, so it is a bit messy and my pic isn't as big as it could be.
Regarding the 10Ohm Cap, I do remember telling you that I had one available, and you suggesting that it may well be an improvement over the old value, and that it was certainly worth trying. It sounds very smooth to me, though I haven't miked up my speakers and done a frequency sweep, so can't be absolutely sure of course.
Regarding the enclosure, I would simply spin it upside down as you say, but I have spikes on the bottom, so I will build a new plywood baffle with the bass driver 1/3 from the top, and remove the mid box to allow a larger volume in the box, which I believe will be beneficial for the bass. I have already replaced the old Celestion upholstery foam with better stuff.
The 15 ohm resistor is a standard 44 component in the standard position, and yes it bridges the + to - , so is indeed in parallel with the Seas tweeter. I included it in the schematic a little late, so it is a bit messy and my pic isn't as big as it could be.
Regarding the 10Ohm Cap, I do remember telling you that I had one available, and you suggesting that it may well be an improvement over the old value, and that it was certainly worth trying. It sounds very smooth to me, though I haven't miked up my speakers and done a frequency sweep, so can't be absolutely sure of course.
Regarding the enclosure, I would simply spin it upside down as you say, but I have spikes on the bottom, so I will build a new plywood baffle with the bass driver 1/3 from the top, and remove the mid box to allow a larger volume in the box, which I believe will be beneficial for the bass. I have already replaced the old Celestion upholstery foam with better stuff.
Celestion 44 crossover circuit , and other comments ...
'ullo Lucas ,
I very much doubt your 44 crossover has the woofer section inductors in the locations of your diagram ,
and the sound would be strange if they were - I say that from experience of filter circuits ,
however it is simpler to refer you to Celestion's own diagram ,
and which you have previously seen here:
http://www.diyaudio.com/forums/multi-way/152995-crossover-nightmare-19.html
-
That is in #188 on Page 19 of the Crossover nightmare!!!!!!! thread.
*** *** ***
It is interesting you hear a "smooth" sound with the Audiophiler 10uF caps in circuit ,
as various listeners around the web report various sounds , albeit relevant to their preferred Reference caps.
Given the wide Sample Variations from production lines at low-cost factories
it is likely all listeners to these caps are correct as all could have differently well/not-well manufactured samples.
It seems you have been fortunate with the pair you bought.
A Frequency Sweep plot is not likely to reveal much about the capacitor's sound , unless they are very resonant-microphonic ,
or substantially high Impedance faulty at high frequencies ,
thus better is simply to decide by listening whether you like them ...
... and it seems you do.
Your previous were less than 10uF , if I am remembering correctly ..?
and if so you would have had loss in the lower treble output after you installed the SEAS tweeter.
With the 1R + 15R L-Pad you will have slightly lower tweeter output than mid-cone output ,
however that is fine if you prefer such , and that will be close to the original Celestion HF2000 tweeter output.
Some listeners to the 66 with that SEAS tweeter are preferring the sound with 27R in Parallel with the tweeter and no Series attenuating resistor.
It really depends on how much treble output one wants to hear.
Changing to 18R Parallel + 0.68R Series is my recommendation to get a fraction more treble but not a distracting amount ,
because the small Series resistance causes the tweeter to produce a similar character of sound to the woofer and mid-cone which both have some resistance in Series with them.
After you change to low DCR Air-core inductors to the woofer you will likely hear a little greater output of bass and low midrange even though the Resistance is not much changed ,
however then you may prefer to nudge up the tweeter output a very little in the option I described above.
*** *** ***
Optimum vertical placement for a Bass frequencies' driver in a cabinet is usually in the Ratio of Internal dimensions of 0.382:0.618 ,
however it can be moved towards the one third:two thirds you stated if the internal Width happens to coincide with a Harmonic of the internal Height.
Measure the Internal's Height , Width , Depth , and Post here.
'ullo Lucas ,
I very much doubt your 44 crossover has the woofer section inductors in the locations of your diagram ,
and the sound would be strange if they were - I say that from experience of filter circuits ,
however it is simpler to refer you to Celestion's own diagram ,
and which you have previously seen here:
http://www.diyaudio.com/forums/multi-way/152995-crossover-nightmare-19.html
-
That is in #188 on Page 19 of the Crossover nightmare!!!!!!! thread.
*** *** ***
It is interesting you hear a "smooth" sound with the Audiophiler 10uF caps in circuit ,
as various listeners around the web report various sounds , albeit relevant to their preferred Reference caps.
Given the wide Sample Variations from production lines at low-cost factories
it is likely all listeners to these caps are correct as all could have differently well/not-well manufactured samples.
It seems you have been fortunate with the pair you bought.
A Frequency Sweep plot is not likely to reveal much about the capacitor's sound , unless they are very resonant-microphonic ,
or substantially high Impedance faulty at high frequencies ,
thus better is simply to decide by listening whether you like them ...
... and it seems you do.
Your previous were less than 10uF , if I am remembering correctly ..?
and if so you would have had loss in the lower treble output after you installed the SEAS tweeter.
With the 1R + 15R L-Pad you will have slightly lower tweeter output than mid-cone output ,
however that is fine if you prefer such , and that will be close to the original Celestion HF2000 tweeter output.
Some listeners to the 66 with that SEAS tweeter are preferring the sound with 27R in Parallel with the tweeter and no Series attenuating resistor.
It really depends on how much treble output one wants to hear.
Changing to 18R Parallel + 0.68R Series is my recommendation to get a fraction more treble but not a distracting amount ,
because the small Series resistance causes the tweeter to produce a similar character of sound to the woofer and mid-cone which both have some resistance in Series with them.
After you change to low DCR Air-core inductors to the woofer you will likely hear a little greater output of bass and low midrange even though the Resistance is not much changed ,
however then you may prefer to nudge up the tweeter output a very little in the option I described above.
*** *** ***
Optimum vertical placement for a Bass frequencies' driver in a cabinet is usually in the Ratio of Internal dimensions of 0.382:0.618 ,
however it can be moved towards the one third:two thirds you stated if the internal Width happens to coincide with a Harmonic of the internal Height.
Measure the Internal's Height , Width , Depth , and Post here.
Last edited:
Thats very interesting.... I have just tried "as not recomanded Lpad with 1R / 12R and 3.9uf and 10uf mondorf mCap 400v, and have to say there is not enough sparkle coming out from SEAS tweeter. Sound is very dark with tiny accent of high end treeble.
I have no chance to buy mundorf 3.6 and 10uf, I could use 600v series 3.3+0.33 or 0.27 and 10 400v + 1uf if thats ok ,otherwise would need to change brand to different one. I will try 27R 10w instead of 1R / 12r Lpad , hope it will bright tweeter a bit.
Regards
Mikolaj
UK
I have no chance to buy mundorf 3.6 and 10uf, I could use 600v series 3.3+0.33 or 0.27 and 10 400v + 1uf if thats ok ,otherwise would need to change brand to different one. I will try 27R 10w instead of 1R / 12r Lpad , hope it will bright tweeter a bit.
Regards
Mikolaj
UK
Resistors to match SEAS 19TFF1 to Celestion crossover
'ullo Mikolaj ,
from your description of the tweeter sound I think you should listen now with only a resistor connected in Parallel with the tweeter ,
and no Series resistor.
If you have already bought the 27 ohm resistors , then put them in and listen ,
then report the results here , or in the Crossover nightmare!!!!!!! thread.
{ I prefer to discuss this crossover in the Crossover nightmare!!!!!!! thread , because we have a lot more about it there now.}
If you have not bought the resistors yet , then if you are going to a shop to buy ,
take your Multimeter and measure some there and buy two that measure higher than 27 to as high as you can find , not lower.
You do not need 10 watt resistors there , 5 watt is sufficient if you are buying a good quality brand.
As you have Mundorf capacitors , I think you may be buying from:
amplifier valve kits, HIFI pre-amplifiers, speaker kits,AMP Parts, upgrade components
They now have Mills MRA-5 , 5 watt , which are very good resistors for Audio.
The MRA-5 are on the same page there as the Mills MRA-12.
For these , buy the 30 ohm , because that will match better to the Celestion 0.14mH Inductor in the crossover than 27 ohms.
Mills are +/- 1% Tolerance , so the 30 ohm will be very close to actual 30 ohms with no need to have measured before sent to you.
Do not change the capacitors , and especially not to 3.3 + 0.33 and 10 + 1 ,
because that will make the sound worse - it will spit in the treble.
You may not have to change the capacitors if the sound is good with the 30 ohm resistor in Parallel.
Mundorf M-Resist MOX resistors are quite good , and better than Jantzen MOX , but are not in 30 ohms ,
so if you decide to buy MOX , buy the 5 watt Mundorf M-Resist and ask the seller to measure some samples of 27 ohm and send you two that measure higher ,
but as you will have to pay for samples to be measured you may as well buy the 30 ohm Mills MRA-5.
If treble is too bright with only the Parallel resistor ,
then make an L-Pad with 18 ohms Parallel , and 0.68 ohm Series.
The primary cause of the sound problem you have now is the 12 ohm resistor ,
because it is causing the Impedance of the tweeter load to be too low to work correctly with the other components in the crossover.
I did NOT recommend 12 ohms for this SEAS tweeter.
I do not know who did , but it is wrong in the other thread you found ,
unless the listener there likes a peculiar flat sound !
'ullo Mikolaj ,
from your description of the tweeter sound I think you should listen now with only a resistor connected in Parallel with the tweeter ,
and no Series resistor.
If you have already bought the 27 ohm resistors , then put them in and listen ,
then report the results here , or in the Crossover nightmare!!!!!!! thread.
{ I prefer to discuss this crossover in the Crossover nightmare!!!!!!! thread , because we have a lot more about it there now.}
If you have not bought the resistors yet , then if you are going to a shop to buy ,
take your Multimeter and measure some there and buy two that measure higher than 27 to as high as you can find , not lower.
You do not need 10 watt resistors there , 5 watt is sufficient if you are buying a good quality brand.
As you have Mundorf capacitors , I think you may be buying from:
amplifier valve kits, HIFI pre-amplifiers, speaker kits,AMP Parts, upgrade components
They now have Mills MRA-5 , 5 watt , which are very good resistors for Audio.
The MRA-5 are on the same page there as the Mills MRA-12.
For these , buy the 30 ohm , because that will match better to the Celestion 0.14mH Inductor in the crossover than 27 ohms.
Mills are +/- 1% Tolerance , so the 30 ohm will be very close to actual 30 ohms with no need to have measured before sent to you.
Do not change the capacitors , and especially not to 3.3 + 0.33 and 10 + 1 ,
because that will make the sound worse - it will spit in the treble.
You may not have to change the capacitors if the sound is good with the 30 ohm resistor in Parallel.
Mundorf M-Resist MOX resistors are quite good , and better than Jantzen MOX , but are not in 30 ohms ,
so if you decide to buy MOX , buy the 5 watt Mundorf M-Resist and ask the seller to measure some samples of 27 ohm and send you two that measure higher ,
but as you will have to pay for samples to be measured you may as well buy the 30 ohm Mills MRA-5.
If treble is too bright with only the Parallel resistor ,
then make an L-Pad with 18 ohms Parallel , and 0.68 ohm Series.
The primary cause of the sound problem you have now is the 12 ohm resistor ,
because it is causing the Impedance of the tweeter load to be too low to work correctly with the other components in the crossover.
I did NOT recommend 12 ohms for this SEAS tweeter.
I do not know who did , but it is wrong in the other thread you found ,
unless the listener there likes a peculiar flat sound !
Last edited:
Hi alan-1-b
I followed you advice and changed Lpad to single 27Ohm resistor connected in Parallel with the tweeter, I had a pair - its an old ceramic version (they measures 26.6 and 26.1 but at least I got a cooperation now). listening in totally flat equalizer results are better ,would even say :much better! but still would add this "tiny pinprick" on high end freq. to give treble even more spark - but that's probably tweeter itself and its restrictions.
I haven't mentions about my overall plans regarding to this project.
I own both dittons 44 and 66, work I am doing on 44 was just to give me some sort of imagination and experience what I could expect in 44 bigger brothers.
I used alcaps (on budget) in mid and bass sections, and Mundorf MKT on treble.
Overall impression is ok, there is nice connections between all 3 drivers very muscular sound but being fussy I would say mids needs much more air and clarity ,they sounds a bit muddy especially on vocals. For the price 44 costs I thing its fair but for 66 I will definitely use Hiquphon OW1 tweeter and better caps for mid and treeble section and that hopefully will compensate what I miss in 44 right now.
Mikolaj
I followed you advice and changed Lpad to single 27Ohm resistor connected in Parallel with the tweeter, I had a pair - its an old ceramic version (they measures 26.6 and 26.1 but at least I got a cooperation now). listening in totally flat equalizer results are better ,would even say :much better! but still would add this "tiny pinprick" on high end freq. to give treble even more spark - but that's probably tweeter itself and its restrictions.
I haven't mentions about my overall plans regarding to this project.
I own both dittons 44 and 66, work I am doing on 44 was just to give me some sort of imagination and experience what I could expect in 44 bigger brothers.
I used alcaps (on budget) in mid and bass sections, and Mundorf MKT on treble.
Overall impression is ok, there is nice connections between all 3 drivers very muscular sound but being fussy I would say mids needs much more air and clarity ,they sounds a bit muddy especially on vocals. For the price 44 costs I thing its fair but for 66 I will definitely use Hiquphon OW1 tweeter and better caps for mid and treeble section and that hopefully will compensate what I miss in 44 right now.
Mikolaj
reasons for the sound problems
'ullo Mikolaj ,
Good , you have heard now some of what is possible with the SEAS tweeter ,
but not yet all that is possible with it.
The Hiquphon OWI may be better , but the SEAS 19TFF1 is not as limited as you are thinking ,
because , as follows:
Human hearing is most sensitive to the Midrange frequencies.
How we hear Midrange affects how we hear the Treble and Bass.
Currently it is the Midrange sound problems that are affecting how you are perceiving the Treble.
Three reasons:
(1)- the Electrolytic caps have significant Dielectric Absorption with its subsequent delayed release of signal , and thus audible colouration in the Midrange ,
both in the Bandpass Filter that feeds the Mid-cone , and in the Low-mids Filter that feeds the Woofer.
(2)- these new electro caps have less ESR than the original electro caps ,
and thus they are suppressing Resonance less in the two Resonant Filters ,
which are the Midrange Bandpass Filter and the 4th Order Woofer Filter.
(3)- the Ferrite cored Inductors in the 44's crossover have Magnetic Hysteresis
to sufficient degree to cause a similar type of delayed colouration to the Dielectric Absorption of the electro caps , though a bit less in magnitude.
{ Dielectric Absorption is also known as Dielectric Hysteresis , if you want to research such.}
Solution:
If you reduce the resonant colourations you will have both clearer mids and slightly more prominent treble ,
because currently the mids' colouration is part-obscuring the treble.
The Treble is less resonant because there are good Polypropylene caps and an Air-core Inductor feeding the tweeter ,
and through a less resonant type of Filter than the other two sections of the crossover.
The Ferrite core Inductors are less a problem than the other two aspects , unless you play the speakers very loudly ,
so for now lets focus on the caps themselves , and their insufficient ESR ,
{ however , replacing the Ferrite cored Inductors with carefully chosen Air-core Inductors will cause audible improvements ,
NOTE: "carefully chosen" , not just any Air Core inductors.}
You can do either of two things:
(1)- replace ALL the electro caps with Polypropylenes + sufficient Series connected Resistance to reduce the resonance in the two filter sections ,
OR ,
(2)- add a small amount of Series connected resistance to the electro caps to reduce the resonance as an Experiment so that you can hear what is further possible ,
as well as hearing a bit more from the tweeter as result.
This can be done with low price ceramic resistors.
Post here whether you want to try the low cost Experiment first , or proceed to the full clean-up ?
I will then advise further.
I have posted a lot about electro caps ; polypropylene caps' various Brands ; ESR ; resonant colourations , etc ...
in both the Crossover nightmare!!!!!!! and celestion 66 needs Mid-range threads.
If you want to use Hiquphon OWI in the 66 you will only hear its benefits sufficiently to justify its price after you attend to the Capacitors and ESR and Resonance in the filter sections of the 66 crossover.
'ullo Mikolaj ,
Good , you have heard now some of what is possible with the SEAS tweeter ,
but not yet all that is possible with it.
The Hiquphon OWI may be better , but the SEAS 19TFF1 is not as limited as you are thinking ,
because , as follows:
Human hearing is most sensitive to the Midrange frequencies.
How we hear Midrange affects how we hear the Treble and Bass.
Currently it is the Midrange sound problems that are affecting how you are perceiving the Treble.
Three reasons:
(1)- the Electrolytic caps have significant Dielectric Absorption with its subsequent delayed release of signal , and thus audible colouration in the Midrange ,
both in the Bandpass Filter that feeds the Mid-cone , and in the Low-mids Filter that feeds the Woofer.
(2)- these new electro caps have less ESR than the original electro caps ,
and thus they are suppressing Resonance less in the two Resonant Filters ,
which are the Midrange Bandpass Filter and the 4th Order Woofer Filter.
(3)- the Ferrite cored Inductors in the 44's crossover have Magnetic Hysteresis
to sufficient degree to cause a similar type of delayed colouration to the Dielectric Absorption of the electro caps , though a bit less in magnitude.
{ Dielectric Absorption is also known as Dielectric Hysteresis , if you want to research such.}
Solution:
If you reduce the resonant colourations you will have both clearer mids and slightly more prominent treble ,
because currently the mids' colouration is part-obscuring the treble.
The Treble is less resonant because there are good Polypropylene caps and an Air-core Inductor feeding the tweeter ,
and through a less resonant type of Filter than the other two sections of the crossover.
The Ferrite core Inductors are less a problem than the other two aspects , unless you play the speakers very loudly ,
so for now lets focus on the caps themselves , and their insufficient ESR ,
{ however , replacing the Ferrite cored Inductors with carefully chosen Air-core Inductors will cause audible improvements ,
NOTE: "carefully chosen" , not just any Air Core inductors.}
You can do either of two things:
(1)- replace ALL the electro caps with Polypropylenes + sufficient Series connected Resistance to reduce the resonance in the two filter sections ,
OR ,
(2)- add a small amount of Series connected resistance to the electro caps to reduce the resonance as an Experiment so that you can hear what is further possible ,
as well as hearing a bit more from the tweeter as result.
This can be done with low price ceramic resistors.
Post here whether you want to try the low cost Experiment first , or proceed to the full clean-up ?
I will then advise further.
I have posted a lot about electro caps ; polypropylene caps' various Brands ; ESR ; resonant colourations , etc ...
in both the Crossover nightmare!!!!!!! and celestion 66 needs Mid-range threads.
If you want to use Hiquphon OWI in the 66 you will only hear its benefits sufficiently to justify its price after you attend to the Capacitors and ESR and Resonance in the filter sections of the 66 crossover.
Last edited:
Project closed
Thank you Allan
I tried 1 of your 2 advices , added some resistors in series to electro caps (used 0.5 / 1 / 1.5 ohm ) mids were not that shouty but still not clear enough
I didnt have time to try other things, as speaker got new owner now I will concentrate more on dittons 66.
It was good to have that occasion to hear at least some of their potential, I know that there could be done much more but as said earlier I was expecting a little bit more.
Had a chat with another owner of ditton 66 who agreed with my opinion about d 44 midrange, whats more he thinks that 66 doesn't solve this problem even though it has a different midrange unit and costs much more, its still the biggest drawback of the 66 - maybe the midrange on these old speakers just can not match modern standards?
As a new tweeter to my Ditton 66 originaly wanted to use Hiquphon OWI but due to its costs (277euro - pair) ,and wanting using better caps in mid and treble sections and not wanting using Seas 19TFF1 (55euro pair) again I decided to try something completely different. EMIT-K ribbon tweeter (100 euro pair) used in Infinity Kappas ,it seems to have about the same output level as the HF-2000. Similar crossover frequency in the Infinity Kappa 7 and the C-66 (4500 and 5000 hz) and it's round flange is 4 inches, same as the HF-2000. Had opportunity to listen to mentioned before Kappa 7 and 8 and I must admit I loved the hights from them - Emit-K and its horizontal dispersion gives you beautiful imaging and airiness ,very fine clarity and enough details. Had a chance to buy them and couldnt resist. they should be with me within next 2 weeks.
the crossover is designed exactly in the same way like this one:
http://www.yatecourtbarn.adsl24.co.uk/images/Ditton 66/Updated 66 Xover0001-1.jpg
caps used in bass and mids are again mundorf mkp 400v same values ised in provided picture ,for treble section Iam thinking about mundorf supreme and resistors instead of mills want to try Duelund - heard just a brilliant opinion about them.
Should I try same values for this new tweeter or it needs to be redesigned from scratch,?
Hope that the overall idea will be gratifying.
Regards
Thank you Allan
I tried 1 of your 2 advices , added some resistors in series to electro caps (used 0.5 / 1 / 1.5 ohm ) mids were not that shouty but still not clear enough
I didnt have time to try other things, as speaker got new owner now I will concentrate more on dittons 66.
It was good to have that occasion to hear at least some of their potential, I know that there could be done much more but as said earlier I was expecting a little bit more.
Had a chat with another owner of ditton 66 who agreed with my opinion about d 44 midrange, whats more he thinks that 66 doesn't solve this problem even though it has a different midrange unit and costs much more, its still the biggest drawback of the 66 - maybe the midrange on these old speakers just can not match modern standards?
As a new tweeter to my Ditton 66 originaly wanted to use Hiquphon OWI but due to its costs (277euro - pair) ,and wanting using better caps in mid and treble sections and not wanting using Seas 19TFF1 (55euro pair) again I decided to try something completely different. EMIT-K ribbon tweeter (100 euro pair) used in Infinity Kappas ,it seems to have about the same output level as the HF-2000. Similar crossover frequency in the Infinity Kappa 7 and the C-66 (4500 and 5000 hz) and it's round flange is 4 inches, same as the HF-2000. Had opportunity to listen to mentioned before Kappa 7 and 8 and I must admit I loved the hights from them - Emit-K and its horizontal dispersion gives you beautiful imaging and airiness ,very fine clarity and enough details. Had a chance to buy them and couldnt resist. they should be with me within next 2 weeks.
the crossover is designed exactly in the same way like this one:
http://www.yatecourtbarn.adsl24.co.uk/images/Ditton 66/Updated 66 Xover0001-1.jpg
caps used in bass and mids are again mundorf mkp 400v same values ised in provided picture ,for treble section Iam thinking about mundorf supreme and resistors instead of mills want to try Duelund - heard just a brilliant opinion about them.
Should I try same values for this new tweeter or it needs to be redesigned from scratch,?
Hope that the overall idea will be gratifying.
Regards
Replies to Post above , including to correct the schematic
'ullo Mikolaj ,
The Ditton 66 midrange can be got to sound good - if the mid-domes are still in good condition.
Perhaps the other owner's mid-domes are partially damaged ,
or , perhaps he does not have the crossover reconditioned correctly.
I posted a lot about the mids' section of the crossover in the 66 midrange thread ,
because if it is not done correctly the sound will be poor quality.
For the crossover schematic in your post:
In the Bass section , reduce the 1.8R to 1.5R .
The capacitors can be as shown , or can be 68uF + 1.5R , and 75uF + 1R.
The 75uF + 1R can be made of a Parallel combination of 68uF + 1R // 8.2uF + 8.2R.
I describe the alternates because those Jantzen 33uF and 39uF are 400 volt and physically very large , and will be difficult to fit on the old board.
Mundorf have 68uF in 250 volt which is smaller than 33 + 39 in 400 volt.
There is 75uF in 250 volt available from overseas sellers , but in UK is only in large 400 volt size.
In the Mid section , increase the 2.7R to 3.3R minimum - do not use 2.7R !
It may need to be 3.9R , depending on the Tweeter used , to get the Mids to integrate with a new Tweeter.
Input cap can be 24uF or 25uF , depending on what is available in the Brand one wants to buy.
Same for output cap , either 3.9uF or 4uF , and maybe larger capacitance there if the mid-dome has a rough response at its high frequency end.
All resistors can be 5 watt , Mills MRA-5 or Mundorf M-Resist metal oxide 5 watt.
Spending money for expensive Duelund resistors will not cause these loudspeakers to sound significantly better.
{ Spend the money getting the EMIT tweeters' Impedance measured , as below ...}
All the components in the Treble section will have to be changed to match the Impedance of the EMIT-K tweeter.
In two photos on ebay I see EMIT tweeters measured with multimeters.
That shows their DCR , 3.3R for one , and 3.5R for the other ,
but DCR is NOT Impedance.
Impedance can change through the frequency bandwidth of the tweeter ,
however for EMIT ribbons it is stated their Impedance is fairly flat ,
so maybe it will be about 3.5R at 5kHz , or maybe it will be higher to perhaps 4.5R ...
I do not know.
Do you have any Test Equipment you can measure its Impedance with ?
We need to see a Plot for its Impedance in the range of about 2.5kHz to a bit higher than 5kHz at least ,
so that the optimum value for the required Inductor can be calculated ,
and then for the two capacitors.
If your Multimeter will measure AC Volts to higher than 5kHz ,
and if you have a Sine Wave generator with sweep frequency ,
or at least a CD with a 5kHz tone , then I can describe how you can calculate the 5kHz Impedance.
For Accuracy you will also need a +/- 1% or better Tolerance resistor of 3.9R or 4.7R , and of 1 watt or higher power.
If you have to buy resistors , then buy 2 in case one is faulty.
Before you do too much , test the mid-domes to hear if still in good condition ,
but NOT with the old capacitors , because if those are leaking significant amounts of low frequencies the mid-domes will get damaged.
Old electrolytic caps do leak , and if you play music loudly through them the old mid-does will be damaged , so I recommend do not.
I recommend you buy 2 new polypropylene caps to connect to listen to the mid-domes through.
If you have some 22uF , that will suffice , but if you are buying then buy the correct 24uF or 25uF.
ClarityCap ESA series has 25uF in 250 volt , and is as good as or better than any Mundorf cap.
The UK Mundorf seller has ClarityCap ESA in 250 volt size.
To test the mid-domes:
Disconnect the treble circuit from the Input of the crossover so no signal can flow into it.
Take out the old 4uF Mids' section cap from the crossover so the circuit is Open there - that is necessary for this test.
{ Leave the 0.34mH inductor there , because you will need it later.}
Put the new 25uF cap into the crossover , { or put in a new condition 22uF cap if you have some }.
Move the mid-dome's + lead to the junction point in the crossover where the 24uF cap connects to the 0.34mH inductor.
The mid-dome is then high-pass filtered only , by the 25uF cap and 2.2mH inductor.
Play music and listen to each mid-dome carefully to hear if both sound the same ,
and if both sound clear in the high-midrange frequencies , { like low treble frequencies }.
If your mid-domes sound good in the experiment above , then it is worth reconditioning the crossover ,
and trying to get the EMIT tweeters correctly integrated into the crossover.
'ullo Mikolaj ,
The Ditton 66 midrange can be got to sound good - if the mid-domes are still in good condition.
Perhaps the other owner's mid-domes are partially damaged ,
or , perhaps he does not have the crossover reconditioned correctly.
I posted a lot about the mids' section of the crossover in the 66 midrange thread ,
because if it is not done correctly the sound will be poor quality.
For the crossover schematic in your post:
In the Bass section , reduce the 1.8R to 1.5R .
The capacitors can be as shown , or can be 68uF + 1.5R , and 75uF + 1R.
The 75uF + 1R can be made of a Parallel combination of 68uF + 1R // 8.2uF + 8.2R.
I describe the alternates because those Jantzen 33uF and 39uF are 400 volt and physically very large , and will be difficult to fit on the old board.
Mundorf have 68uF in 250 volt which is smaller than 33 + 39 in 400 volt.
There is 75uF in 250 volt available from overseas sellers , but in UK is only in large 400 volt size.
In the Mid section , increase the 2.7R to 3.3R minimum - do not use 2.7R !
It may need to be 3.9R , depending on the Tweeter used , to get the Mids to integrate with a new Tweeter.
Input cap can be 24uF or 25uF , depending on what is available in the Brand one wants to buy.
Same for output cap , either 3.9uF or 4uF , and maybe larger capacitance there if the mid-dome has a rough response at its high frequency end.
All resistors can be 5 watt , Mills MRA-5 or Mundorf M-Resist metal oxide 5 watt.
Spending money for expensive Duelund resistors will not cause these loudspeakers to sound significantly better.
{ Spend the money getting the EMIT tweeters' Impedance measured , as below ...}
All the components in the Treble section will have to be changed to match the Impedance of the EMIT-K tweeter.
In two photos on ebay I see EMIT tweeters measured with multimeters.
That shows their DCR , 3.3R for one , and 3.5R for the other ,
but DCR is NOT Impedance.
Impedance can change through the frequency bandwidth of the tweeter ,
however for EMIT ribbons it is stated their Impedance is fairly flat ,
so maybe it will be about 3.5R at 5kHz , or maybe it will be higher to perhaps 4.5R ...
I do not know.
Do you have any Test Equipment you can measure its Impedance with ?
We need to see a Plot for its Impedance in the range of about 2.5kHz to a bit higher than 5kHz at least ,
so that the optimum value for the required Inductor can be calculated ,
and then for the two capacitors.
If your Multimeter will measure AC Volts to higher than 5kHz ,
and if you have a Sine Wave generator with sweep frequency ,
or at least a CD with a 5kHz tone , then I can describe how you can calculate the 5kHz Impedance.
For Accuracy you will also need a +/- 1% or better Tolerance resistor of 3.9R or 4.7R , and of 1 watt or higher power.
If you have to buy resistors , then buy 2 in case one is faulty.
Before you do too much , test the mid-domes to hear if still in good condition ,
but NOT with the old capacitors , because if those are leaking significant amounts of low frequencies the mid-domes will get damaged.
Old electrolytic caps do leak , and if you play music loudly through them the old mid-does will be damaged , so I recommend do not.
I recommend you buy 2 new polypropylene caps to connect to listen to the mid-domes through.
If you have some 22uF , that will suffice , but if you are buying then buy the correct 24uF or 25uF.
ClarityCap ESA series has 25uF in 250 volt , and is as good as or better than any Mundorf cap.
The UK Mundorf seller has ClarityCap ESA in 250 volt size.
To test the mid-domes:
Disconnect the treble circuit from the Input of the crossover so no signal can flow into it.
Take out the old 4uF Mids' section cap from the crossover so the circuit is Open there - that is necessary for this test.
{ Leave the 0.34mH inductor there , because you will need it later.}
Put the new 25uF cap into the crossover , { or put in a new condition 22uF cap if you have some }.
Move the mid-dome's + lead to the junction point in the crossover where the 24uF cap connects to the 0.34mH inductor.
The mid-dome is then high-pass filtered only , by the 25uF cap and 2.2mH inductor.
Play music and listen to each mid-dome carefully to hear if both sound the same ,
and if both sound clear in the high-midrange frequencies , { like low treble frequencies }.
If your mid-domes sound good in the experiment above , then it is worth reconditioning the crossover ,
and trying to get the EMIT tweeters correctly integrated into the crossover.
Last edited:
Alan!
Thats a lot of info... as soon I get those EMITS I will have a look what they measure.
You can have a look from what components was build Kappa 7 using those tweeters , just see link bellow it contains all Kappa_7_technical info about those speakers so maybe that would give some more additional help to presume their real values.
http://www.infinity-classics.de/technik/manuals/Kappa_7_technical_sheet.pdf
Unfortunatelly I do not have any fancy equipment like Sine Wave generator, just an universal multimeter and soldering gun
Thats a lot of info...
as soon I get those EMITS I will have a look what they measure.You can have a look from what components was build Kappa 7 using those tweeters , just see link bellow it contains all Kappa_7_technical info about those speakers so maybe that would give some more additional help to presume their real values.
http://www.infinity-classics.de/technik/manuals/Kappa_7_technical_sheet.pdf
Unfortunatelly I do not have any fancy equipment like Sine Wave generator, just an universal multimeter and soldering gun
Information needed to integrate the EMIT tweeter
'ullo Mikolaj ,
The Kappa RS 7 specifications give us only limited useful information about the EMIT tweeter.
As the entire loudspeaker is specified as 88dB/w/M Sensitivity ,
and there is a 5R potentiometer at the tweeter , this tweeter will have larger than 88dB Sensitivity ,
so we will need to know its Sensitivity to be able to integrate it into the Celestion 66.
Putting a Potentiometer into the crossover is not good for long term sound quality !
If we can find its Sensitivity , a suitable resistance may be able to be Series added to the tweeter Impedance
for the combined load to match the Celestion 0.14mH inductor currently in the crossover ,
as well as matching the Sensitivity to that of the mid-dome and woofer.
Search the Internet for Specifications for this EMIT-K version 902-3082 .
Hopefully some-one has measured them , or has an original Manufacturer's Data Sheet somewhere ...
What is the Brand and Model Number of your Multimeter ?
Also , look in the Manual for it and find the Specification for its Frequency Response for its AC Volts ranges , and post those here please ?
Which version of the Celestion 66 do you have ?
The first version has Black coloured capacitors in all of its crossover ,
and the MkII has Green capacitors in the tweeter section of its crossover.
Do you have any Capacitors , new condition Bipolar Electrolytic ?
old or new plastic film/foil or metalized film types ?
List here any values you have , because some you may be able to use to test the tweeter in circuit , so we can decide what you may need to buy.
While you are waiting for the EMITs to arrive , I recommend you do the listening test I described for your mid-domes.
What tweeters are currently in your 66s ?
'ullo Mikolaj ,
The Kappa RS 7 specifications give us only limited useful information about the EMIT tweeter.
As the entire loudspeaker is specified as 88dB/w/M Sensitivity ,
and there is a 5R potentiometer at the tweeter , this tweeter will have larger than 88dB Sensitivity ,
so we will need to know its Sensitivity to be able to integrate it into the Celestion 66.
Putting a Potentiometer into the crossover is not good for long term sound quality !
If we can find its Sensitivity , a suitable resistance may be able to be Series added to the tweeter Impedance
for the combined load to match the Celestion 0.14mH inductor currently in the crossover ,
as well as matching the Sensitivity to that of the mid-dome and woofer.
Search the Internet for Specifications for this EMIT-K version 902-3082 .
Hopefully some-one has measured them , or has an original Manufacturer's Data Sheet somewhere ...
What is the Brand and Model Number of your Multimeter ?
Also , look in the Manual for it and find the Specification for its Frequency Response for its AC Volts ranges , and post those here please ?
Which version of the Celestion 66 do you have ?
The first version has Black coloured capacitors in all of its crossover ,
and the MkII has Green capacitors in the tweeter section of its crossover.
Do you have any Capacitors , new condition Bipolar Electrolytic ?
old or new plastic film/foil or metalized film types ?
List here any values you have , because some you may be able to use to test the tweeter in circuit , so we can decide what you may need to buy.
While you are waiting for the EMITs to arrive , I recommend you do the listening test I described for your mid-domes.
What tweeters are currently in your 66s ?
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