Hello Chaps, been a while since I was on here and even had to reregister as my email has changed.
I just recently pulled my old Diesis MinI bookshelf speakers from the loft. I bought them new in 1979. They were made by Brian O’Rourke and marketed as Diesis. Brian went on to create Ruark Speakers with his son Alan. They are only down the road from me too. These speakers were very solid and fitted with SEAS tweeter and Woofer/mid, and a SEAS supplied crossover. i bought them after a blind test in the shop and they mistakenly played some Spendors and I went Oh yes. They said oops mistake as they are well put of your price , but these Diesis have a similar sound signature and he was right, they cost a bit more than my limit… But they are very smooth but with no colouration.
Ive been through some Dutton 33’s and 332‘s and more recently Rega RS5s but the little Diesis kept calling, especially as they are small enough for the missus to accept in the lounge.
Anyway, back to the present day:
Hooked them up and realized one speaker was quieter than the other. So did the usual and ascertained its the speaker not amp or anything else. Took them apart and saw to my dismay that the 2 woofers are covered in oxidation so that needs doing. Then noticed that the crossover looked a bit cooked on the one that was quieter. So I set out to try to ascertain all the values. Not so easy , so I hooked out the other crossover only to find it has different make caps etc. A bit odd as I bought them new so no one has fiddled with them.
So, I’m struggling to see what size the Inductors are. I can read the Caps on one crossover ok so that good. Also the resistors on that board , not so easy on the other board. Both the air cooled Inductors look ok and I’m to understand they rarely have a problem.
So here is the information I can see. Hoping someone on here can work out what I need to buy …
Crossover 1 :Has a sticker which reads : D 093 P 8ohm, 2-way 3120176, fc: 2000Hz.
Inductor; 6F8 5%
Caps 1; CEO 2SP 50V 12mF (K) The m is actually the symbol for micro but can’t find it on my keyboard.
Caps 2; CEO 2SP 50V 8mF (K)
Resistors 1; RGB5 10 Ohms J Noble62
Resistors 2; 5W 7 Ohms J Micron86
Crossover 2:
Inductor; can’t read at all
Caps 1 ; 12mF 50V
Caps 2 ; Can’t read till I remove it.
Resistors 1; D(ohms symbol) C. 811 4R7 5% 5W
Resistors 2; can’t read at all.
I will upload a photo of the crossovers. I have more photos if anyone needs extra.
Appreciate any help to get these up and running as to be honest id forgotten how nice they sound, even with one speaker a bit quieter… ( I have Attacama Stands for them.)
I know these are not or even were not state of the art speakers but do you guys think standard Alcap Caps and equivalent Resistors and inductors will be ok or should I go a bit more upmarket? I will likely use Falcon Accoustics or Wilmslow Audio as im in the UK.
Thank you guys, appreciate any help at all.
Cheers
Phil
I just recently pulled my old Diesis MinI bookshelf speakers from the loft. I bought them new in 1979. They were made by Brian O’Rourke and marketed as Diesis. Brian went on to create Ruark Speakers with his son Alan. They are only down the road from me too. These speakers were very solid and fitted with SEAS tweeter and Woofer/mid, and a SEAS supplied crossover. i bought them after a blind test in the shop and they mistakenly played some Spendors and I went Oh yes. They said oops mistake as they are well put of your price , but these Diesis have a similar sound signature and he was right, they cost a bit more than my limit… But they are very smooth but with no colouration.
Ive been through some Dutton 33’s and 332‘s and more recently Rega RS5s but the little Diesis kept calling, especially as they are small enough for the missus to accept in the lounge.
Anyway, back to the present day:
Hooked them up and realized one speaker was quieter than the other. So did the usual and ascertained its the speaker not amp or anything else. Took them apart and saw to my dismay that the 2 woofers are covered in oxidation so that needs doing. Then noticed that the crossover looked a bit cooked on the one that was quieter. So I set out to try to ascertain all the values. Not so easy , so I hooked out the other crossover only to find it has different make caps etc. A bit odd as I bought them new so no one has fiddled with them.
So, I’m struggling to see what size the Inductors are. I can read the Caps on one crossover ok so that good. Also the resistors on that board , not so easy on the other board. Both the air cooled Inductors look ok and I’m to understand they rarely have a problem.
So here is the information I can see. Hoping someone on here can work out what I need to buy …
Crossover 1 :Has a sticker which reads : D 093 P 8ohm, 2-way 3120176, fc: 2000Hz.
Inductor; 6F8 5%
Caps 1; CEO 2SP 50V 12mF (K) The m is actually the symbol for micro but can’t find it on my keyboard.
Caps 2; CEO 2SP 50V 8mF (K)
Resistors 1; RGB5 10 Ohms J Noble62
Resistors 2; 5W 7 Ohms J Micron86
Crossover 2:
Inductor; can’t read at all
Caps 1 ; 12mF 50V
Caps 2 ; Can’t read till I remove it.
Resistors 1; D(ohms symbol) C. 811 4R7 5% 5W
Resistors 2; can’t read at all.
I will upload a photo of the crossovers. I have more photos if anyone needs extra.
Appreciate any help to get these up and running as to be honest id forgotten how nice they sound, even with one speaker a bit quieter… ( I have Attacama Stands for them.)
I know these are not or even were not state of the art speakers but do you guys think standard Alcap Caps and equivalent Resistors and inductors will be ok or should I go a bit more upmarket? I will likely use Falcon Accoustics or Wilmslow Audio as im in the UK.
Thank you guys, appreciate any help at all.
Cheers
Phil
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For some reason you have two wires that look like they overheated, where they shorting inside the cabinet and did you have to pull them apart when you removed the drivers from the cabinet?
The fact that the wires look charred may have caused the caps to let loose along with the overheated resistors.
Back to the crossover, I can see per board: one coil, three resistors and two capacitors. Not two coils?
I would remove the corrosion outdoors and stand upwind or at least where some kind of face mask.
The fact that the wires look charred may have caused the caps to let loose along with the overheated resistors.
Back to the crossover, I can see per board: one coil, three resistors and two capacitors. Not two coils?
I would remove the corrosion outdoors and stand upwind or at least where some kind of face mask.
Hi Dave. What pictures specifically would you like?
Raymondj, No I didn’t pull them apart but it could’ve done when I pulled the woofers out.
Ah I thought the black looking tubes were inductors . I didn’t think you needed 3 resistors on a 2 way? Shows how much I know 😬…
Yes will watch the dust definitely….
Thanks
Phil
Raymondj, No I didn’t pull them apart but it could’ve done when I pulled the woofers out.
Ah I thought the black looking tubes were inductors . I didn’t think you needed 3 resistors on a 2 way? Shows how much I know 😬…
Yes will watch the dust definitely….
Thanks
Phil
A cheap DVM with a resistance range would allow you to measure the resistors assuming they haven't gone open circuit. The picture of the wire wound resistor suggests that is a 6.8 ohm resistor.
It would be worth checking the drive units themselves with the DVM set to resistance to see that they are in the ballpark of 3 to 8 ohms and that the woofer and tweeter basically match each other and are not out of spec or short circuit.
It would be worth checking the drive units themselves with the DVM set to resistance to see that they are in the ballpark of 3 to 8 ohms and that the woofer and tweeter basically match each other and are not out of spec or short circuit.
Thank you guys. I will get my multimeter out and check the resistors and Caps. I does seem odd for wiring to overheat. I’ve never had the speakers on too powerful an amp or even had them overworked. So presuming it can only be something broke down in the CO.
I will check the speakers now they are out. I checked them at the input and both boxes were about 8Ohms.
Thanks again
Phil
I will check the speakers now they are out. I checked them at the input and both boxes were about 8Ohms.
Thanks again
Phil
Ok so just popped out to garage and checked the speakers and both woofers are reading 8 Ohms as specified on their labels. One of the tweeters is measuring 6 Ohms as specified but the other is only 2 Ohms. I presume this means the tweeter needs to be replaced - or in fact both so they match.
Both the woofers are moving freely and also looks like the tweeters move ok too. Is it possible to repair the tweeter?
Also measured the resistors and the 2 black wire wound ones both measure 3.8 Ohms.
So bit of research needed for sensible tweeter replacement and then I can order the parts . I will need some internal wire where it’s burnt. It measures 0.6mm wire and 1.4mm on the casing. So I’m assuming 22 gauge.
Any recommendations for purchase of these parts ? I used Falcon Accoustics before.
Thanks
Phil
Both the woofers are moving freely and also looks like the tweeters move ok too. Is it possible to repair the tweeter?
Also measured the resistors and the 2 black wire wound ones both measure 3.8 Ohms.
So bit of research needed for sensible tweeter replacement and then I can order the parts . I will need some internal wire where it’s burnt. It measures 0.6mm wire and 1.4mm on the casing. So I’m assuming 22 gauge.
Any recommendations for purchase of these parts ? I used Falcon Accoustics before.
Thanks
Phil
Ok guys i have managed to source the SEAS H1212 in France at TLHP at a reasonable cost. Should i go with these as they are discontinued now .
i already have 2 Solen 400V 12 mF caps spare from a Ditton 332 rebuild. So i can source 2x 8.2mF Solen 400V instead of 8mF.
Resistors I will go for 10W due to the heat issues i see on the board. 2 x 10Ohms , 2 x 6.8 Ohms and 2 x 3.8 Ohms . So 6.8 instead of 7 and 3.9 instead of measured 3.8. Do you think this will be noticeable ?
Internal wire 22 gauge i can get from Amazon as Falcon dont seem to have any.
How does that sound or am i jumping the gun on the tweeter? I dont want to miss them as they only have 4 left and they are discontinued now. £88 the pair posted.
Im getting itchy fingers now . Once I’ve got these ordered I’ll get cracking on the cabinets which need a light rub down and re oiling. And also cleaning the woofers oxidation off
Thanks guys, appreciate your inputs.
Phil
i already have 2 Solen 400V 12 mF caps spare from a Ditton 332 rebuild. So i can source 2x 8.2mF Solen 400V instead of 8mF.
Resistors I will go for 10W due to the heat issues i see on the board. 2 x 10Ohms , 2 x 6.8 Ohms and 2 x 3.8 Ohms . So 6.8 instead of 7 and 3.9 instead of measured 3.8. Do you think this will be noticeable ?
Internal wire 22 gauge i can get from Amazon as Falcon dont seem to have any.
How does that sound or am i jumping the gun on the tweeter? I dont want to miss them as they only have 4 left and they are discontinued now. £88 the pair posted.
Im getting itchy fingers now . Once I’ve got these ordered I’ll get cracking on the cabinets which need a light rub down and re oiling. And also cleaning the woofers oxidation off
Thanks guys, appreciate your inputs.
Phil
SEAS H1212 tweeter data:
https://seas.no/index.php?option=com_content&view=article&id=69:h1212-06-27tbfcg&catid=45&Itemid=239
Which relates to a metal dome tweeter. Maybe a chat with the staff at Falcon may throw up some other suggestion or they may be able to point out which tweeter repair kit could be used to replace the low reading 2 ohm voice coil one.
The TLHP website has some SEAS tweeter replacement domes as well, but i do not know the which one is the suggested replacement , if any. I guess you could ask the question via email or chat to them as well.
No problem with ordering from either supplier in my experience. I had some stuff from TLHP some weeks ago and they were delivered v quickly.
https://seas.no/index.php?option=com_content&view=article&id=69:h1212-06-27tbfcg&catid=45&Itemid=239
Which relates to a metal dome tweeter. Maybe a chat with the staff at Falcon may throw up some other suggestion or they may be able to point out which tweeter repair kit could be used to replace the low reading 2 ohm voice coil one.
The TLHP website has some SEAS tweeter replacement domes as well, but i do not know the which one is the suggested replacement , if any. I guess you could ask the question via email or chat to them as well.
No problem with ordering from either supplier in my experience. I had some stuff from TLHP some weeks ago and they were delivered v quickly.
I see that for some tweeters you can buy the voice coil already to go on . But can’t see any for the H107’s. Too old i suspect.
I will likely order the new H1212’s from TLHP.
Ordered the internal wire today , 22gauge as fitted so i know it’ll go through the holes in the boards.
Will order the Caps and resistors today from Falcon. I should be ok with the slight differences in sizes as they will still be within the 5%.
What foam would you recommend for these little speakers? I see Falcon have a few types and thicknesses. Should I go for the same thickness as originally fitted?
Ta,
Phil
I will likely order the new H1212’s from TLHP.
Ordered the internal wire today , 22gauge as fitted so i know it’ll go through the holes in the boards.
Will order the Caps and resistors today from Falcon. I should be ok with the slight differences in sizes as they will still be within the 5%.
What foam would you recommend for these little speakers? I see Falcon have a few types and thicknesses. Should I go for the same thickness as originally fitted?
Ta,
Phil
Ok so ordered the caps,resistors and the new tweeters from TLHP.
I took the tweeters apart and the voice coil on the broken one looks likes its heated up and moved. It’s very fine wire and i don’t trust myself to rewind it with new fresh wire and re solder the ends.
I looked at new foam and it’s very expensive for what it is … and then plus postage as it’s a bulky item. So gonna try to source something more economic locally which still does a good job….
Phil
I took the tweeters apart and the voice coil on the broken one looks likes its heated up and moved. It’s very fine wire and i don’t trust myself to rewind it with new fresh wire and re solder the ends.
I looked at new foam and it’s very expensive for what it is … and then plus postage as it’s a bulky item. So gonna try to source something more economic locally which still does a good job….
Phil
Speaker foam is expensive in UK and as you say and because of the bulk means its expensive to ship. Somebody once told me that due to regulations they could only post each sheet as a single item?
If the foam isn't falling to pieces as you remove it I imagine it is probably still useable for the time being.
Depending on replacement tweeter and listening you may have to try some different resistor values to balance the sound. It might be worth posting an image of the underside of the pcb so we can understand exactly how the original crossover was configured? Original data sheets would be a handy reference as well?
If the foam isn't falling to pieces as you remove it I imagine it is probably still useable for the time being.
Depending on replacement tweeter and listening you may have to try some different resistor values to balance the sound. It might be worth posting an image of the underside of the pcb so we can understand exactly how the original crossover was configured? Original data sheets would be a handy reference as well?