hi guys,
I think I put my fingers into something I can't handle. I've been lurking for a while, without finding answers. I was about to proceed by trial and error but I guess I should first ask Internet...
tldr: I've no data, and I need to choose a new pair of tweeter
I found some old 3 ways speakers (25yo? ~90x60x40cm h/w/d, ported box woofer, enclosed mids and tweets) hand made by a dead company. (I wanted to quickly restore them for an association I'm part of). But one of the tweeter is missing, so I would need to replace both of them. Sadly besides being able to measure that they are having 8ohms of resistance, I've no rating. They are numbers on the back of the speakers but they look like old serial numbers and internet couldn't help me (tweet: 4988 and 8B on the basket, mid: 5293/5, woofer: 4986/1 and 7M on the basket). I work in electronics but not so much with this kind of stuffs. I wrapped my head around that with my colleague and we concluded that we could only get a a guess at the last original tweet wattage by blowing it, but this won't give us anything about sensitivity in order to have a kinda balanced speaker...
I'm currently working on the filters (some weld "dried", not sure of the proper English word sorry, and I'm waiting new potentiates because one of them burned badly). But from then on, I'm helpless.
Would there be any advice on how to proceed? Would there be another way then trial and error (even if it's just an estimation)? Anything I can mesure to help me take an educated guess (something on the old tweet I still have, the size of the tweet enclosure? mesuring the watt drawing difference between the speaker with or without the tweet, idk...)
If I can't find anything, what would be a safe option? should I look for a tweet with high wattage low sensitivity to be sure to not blow it?
Thanks a lot for any help!
(if it is of any help, I can upload pics of the speakers and their parts)
I think I put my fingers into something I can't handle. I've been lurking for a while, without finding answers. I was about to proceed by trial and error but I guess I should first ask Internet...
tldr: I've no data, and I need to choose a new pair of tweeter
I found some old 3 ways speakers (25yo? ~90x60x40cm h/w/d, ported box woofer, enclosed mids and tweets) hand made by a dead company. (I wanted to quickly restore them for an association I'm part of). But one of the tweeter is missing, so I would need to replace both of them. Sadly besides being able to measure that they are having 8ohms of resistance, I've no rating. They are numbers on the back of the speakers but they look like old serial numbers and internet couldn't help me (tweet: 4988 and 8B on the basket, mid: 5293/5, woofer: 4986/1 and 7M on the basket). I work in electronics but not so much with this kind of stuffs. I wrapped my head around that with my colleague and we concluded that we could only get a a guess at the last original tweet wattage by blowing it, but this won't give us anything about sensitivity in order to have a kinda balanced speaker...
I'm currently working on the filters (some weld "dried", not sure of the proper English word sorry, and I'm waiting new potentiates because one of them burned badly). But from then on, I'm helpless.
Would there be any advice on how to proceed? Would there be another way then trial and error (even if it's just an estimation)? Anything I can mesure to help me take an educated guess (something on the old tweet I still have, the size of the tweet enclosure? mesuring the watt drawing difference between the speaker with or without the tweet, idk...)
If I can't find anything, what would be a safe option? should I look for a tweet with high wattage low sensitivity to be sure to not blow it?
Thanks a lot for any help!
(if it is of any help, I can upload pics of the speakers and their parts)
Indeed, got a lot of data sheets from the '80s-90s, so a good chance there's one that at least looks ~like what he has or if really cheap, then he can browse the RadioShack archives. 😉 Then again, maybe he should start there.......
1) they are HUGE, and probably way over 25 y.o.
2) you would make an excellent Secret Agent 😉 .... able to answer under duress but giving no usable information 😱
Please post those pictures, also of any labels found on that cabinet anywhere.
3) specially closeup pictures of the remaining tweeter, its hole in the cabinet and some measurements, specially tweeter and hole diameter, etc.
If possible, in mm, way more precise and simple than funny fractional inch measurements, which need converting to Metric anyway.
4) there must/should be a crossover there, so we also need pictures where component values are readable, if present, that will also guide us when choosing tweeters.
5) in principle, you will be able to repair your cabinets by buying 2 modern tweeters which fit in those holes and reasonably match current drivers and crossover,, cabinet WILL work, maybe not exactly as originals or like a 2020´s model but usable enough.
As is ........
2) you would make an excellent Secret Agent 😉 .... able to answer under duress but giving no usable information 😱
Please post those pictures, also of any labels found on that cabinet anywhere.
3) specially closeup pictures of the remaining tweeter, its hole in the cabinet and some measurements, specially tweeter and hole diameter, etc.
If possible, in mm, way more precise and simple than funny fractional inch measurements, which need converting to Metric anyway.
4) there must/should be a crossover there, so we also need pictures where component values are readable, if present, that will also guide us when choosing tweeters.
5) in principle, you will be able to repair your cabinets by buying 2 modern tweeters which fit in those holes and reasonably match current drivers and crossover,, cabinet WILL work, maybe not exactly as originals or like a 2020´s model but usable enough.
As is ........
God! It's my first time asking help around here and I was not expecting this! Thanks so much everyone!
Sorry, for the picture, I didn't have them on hand last night, so here they are!
The tweeter hole is 95mm, the hole/horn for the dome is ~50mm and the mounting screws are making a square of 120mm of diagonal (which is already a painful size as most modern tweeters are much smaller, I'm ready to laser cut piece of wood to make an intermediary step if needed).
I'll enclose all the pics (included the filters, the blown potentiometer etc.). From what I saw, many parts are looking like they came from Monacor (electronic from the filters, handled, corner protections, ...; some are branded, others I just recognized) I've contact with them thanks to my job but I couldn't get in contact yet with a technician who could identify that. As you can see they have been built in France (Grenoble), but besides having their phone number on old phone registry websites... they look pretty dead.
If someone is interested in the investigation or would have any kind of clue or lead, I'm taking any help you could give 😀
NB: as you can see on the pic with them both, the missing tweeter had been replaced by a small horn really not fitting the case. So I guess a random guy put it but had no clue about anything, so I'm not using it for reference
Sorry, for the picture, I didn't have them on hand last night, so here they are!
The tweeter hole is 95mm, the hole/horn for the dome is ~50mm and the mounting screws are making a square of 120mm of diagonal (which is already a painful size as most modern tweeters are much smaller, I'm ready to laser cut piece of wood to make an intermediary step if needed).
I'll enclose all the pics (included the filters, the blown potentiometer etc.). From what I saw, many parts are looking like they came from Monacor (electronic from the filters, handled, corner protections, ...; some are branded, others I just recognized) I've contact with them thanks to my job but I couldn't get in contact yet with a technician who could identify that. As you can see they have been built in France (Grenoble), but besides having their phone number on old phone registry websites... they look pretty dead.
If someone is interested in the investigation or would have any kind of clue or lead, I'm taking any help you could give 😀
NB: as you can see on the pic with them both, the missing tweeter had been replaced by a small horn really not fitting the case. So I guess a random guy put it but had no clue about anything, so I'm not using it for reference
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Just thinking aloud and in no particular order:
1) Danold Audio is a French PA Speaker manufacturer/assembler, the cabinet screams that, down to the sprayed on textured finish, metal grills, (broken) corner protectors (which you must replace) and folding side mounted metallic handles.
Obviously built out of locally available components, so European unless otherwise stated.
Like many small companies, it looks no longer active and somewhat obscure so hard to find data from.
Baxon is the model/line name, some effort is evident since the large crossover board is custom made, and etched Baxon on the copper side, meaning at least a batch of them was made.
Not a one-off made out of over the shelf components.
2) Monacor is a huge and still much alive German speaker manufacturer and supplier, specializing in PA speaker components, they even offer PA speaker kits, so Danold may very well have built a product line based on Monacor stuff, but using a custom made crossover.
It might even have been made for them by Monacor.
https://www.monacor.com/products/components/speaker-technology/
That said, the smaller board, clearly dedicated for the original dome tweeter, is labelled Ciare, a distinguished Italian speaker manufacturer, and gain fitting the European source theory.
3) Monacor still today offers this dome tweeter for PA use, quite close to what you have.
https://www.monacor.com/products/co...gy/pa-tweeters-and-horn-drivers-/ht-958pa-sw/
size is close enough, you might need to slightly enlarge hole or make an adapter ring, no big deal:
response is impressive for a Dome tweeter, incredibly loud (100dB 😱 ), clearly dedicated to PA duty:
I would buy two of them so both cabinets match each other..
That said, Dome tweeters are fragile for PA use, from crossover pictures it´s clear Danold/Baxon must have had a string of blown tweeters, so they went over the top to protect them, from the car bulb protector (typically 12V - 12/15W) to the built inside 😱 attenuator !!!!
But you are repairing those cabinets, not re-engineering, so replace them with the (close to) original ones.
Any regular (Hi Fi) dome will be too weak there.
1) Danold Audio is a French PA Speaker manufacturer/assembler, the cabinet screams that, down to the sprayed on textured finish, metal grills, (broken) corner protectors (which you must replace) and folding side mounted metallic handles.
Obviously built out of locally available components, so European unless otherwise stated.
Like many small companies, it looks no longer active and somewhat obscure so hard to find data from.
Baxon is the model/line name, some effort is evident since the large crossover board is custom made, and etched Baxon on the copper side, meaning at least a batch of them was made.
Not a one-off made out of over the shelf components.
2) Monacor is a huge and still much alive German speaker manufacturer and supplier, specializing in PA speaker components, they even offer PA speaker kits, so Danold may very well have built a product line based on Monacor stuff, but using a custom made crossover.
It might even have been made for them by Monacor.
https://www.monacor.com/products/components/speaker-technology/
That said, the smaller board, clearly dedicated for the original dome tweeter, is labelled Ciare, a distinguished Italian speaker manufacturer, and gain fitting the European source theory.
3) Monacor still today offers this dome tweeter for PA use, quite close to what you have.
https://www.monacor.com/products/co...gy/pa-tweeters-and-horn-drivers-/ht-958pa-sw/
size is close enough, you might need to slightly enlarge hole or make an adapter ring, no big deal:
response is impressive for a Dome tweeter, incredibly loud (100dB 😱 ), clearly dedicated to PA duty:
I would buy two of them so both cabinets match each other..
That said, Dome tweeters are fragile for PA use, from crossover pictures it´s clear Danold/Baxon must have had a string of blown tweeters, so they went over the top to protect them, from the car bulb protector (typically 12V - 12/15W) to the built inside 😱 attenuator !!!!
But you are repairing those cabinets, not re-engineering, so replace them with the (close to) original ones.
Any regular (Hi Fi) dome will be too weak there.
Maybe this is why Monacor have this product.
https://www.monacor.com/products/di...ors-volume-controls-speaker-protection/dsp-1/
I'd like to see a photo of the outside of the terminal block too.
Are they 1/4" jack fittings?
https://www.monacor.com/products/di...ors-volume-controls-speaker-protection/dsp-1/
I'd like to see a photo of the outside of the terminal block too.
Are they 1/4" jack fittings?
If those drivers are Monacor then the drivers may have modern equivalents and JMFahey is most often right about this stuff.
I just looked at woofers and midrange drivers there and similar looking units are listed.
Somewhat better than garage party boxes then it this is the case
I just looked at woofers and midrange drivers there and similar looking units are listed.
Somewhat better than garage party boxes then it this is the case
I'd bet that a Ciare tweeter went along with a Ciare crossover board. The L-pad knob looks a lot like ones I got from MCM around 1988, but the rest of the crossover stuff makes me think early 1980s. There could be a date code on some components, or on the solder side crossover circuit board.
There's an efficient horn-loaded dome tweeter from Audax, PR125T1. I was under the impression that Audax drivers weren't available anymore, but searching finds a few European vendors that appear to have stock.
https://en.toutlehautparleur.com/un...1-0-inch-voice-coil-3-94-inch-front-side.html
There's an efficient horn-loaded dome tweeter from Audax, PR125T1. I was under the impression that Audax drivers weren't available anymore, but searching finds a few European vendors that appear to have stock.
https://en.toutlehautparleur.com/un...1-0-inch-voice-coil-3-94-inch-front-side.html
Thank you so much everyone for your inputs! I was about to summarize the leads but Eureka! I found it! Looks like it was a Ciare indeed, the 1.26 tw! http://oem.ciare.com/en/440/314/prodotti.php
The picture and the size is really close. I've 120mm between the external screws and here the total diameter is 130mm. It is indeed a (very) high sentisivity speaker, but it's apparently an aluminum dome. 8ohm, 20watts AES (not RMS!).
Given some reviews I've seen about Ciare, the diagram of these speakers, JMFahey's observation about the board design to counter some fragility, and the fact that one of them blew... I guess I'll look for another option to change them lol
So regarding a substituion option, Monacor's HT-958PA looks like a good compromise. The sensitivity isn't as high, but he can handle a higher wattage and has a decent linearity. @JMFahey would you stick to your recommandation with these new info?
Will I get much trebble loss by not using a 105db tweeter? Or should I hold this as requierment, go for horns and saw the hole to fit horns inside?
@Moondog55, nope, no 6,3mm jack, only XLR male and female.
And here enclosed, the other side of the board for your curiosity, with the "model number" (I guess) ERCEE FI-86 on the left.
Do you guys have some special recommendation/advice regarding the last steps of the restauration? Like should I kick this bulb as I'm changing the tweeter? Should I change the wires?
The picture and the size is really close. I've 120mm between the external screws and here the total diameter is 130mm. It is indeed a (very) high sentisivity speaker, but it's apparently an aluminum dome. 8ohm, 20watts AES (not RMS!).
Given some reviews I've seen about Ciare, the diagram of these speakers, JMFahey's observation about the board design to counter some fragility, and the fact that one of them blew... I guess I'll look for another option to change them lol
So regarding a substituion option, Monacor's HT-958PA looks like a good compromise. The sensitivity isn't as high, but he can handle a higher wattage and has a decent linearity. @JMFahey would you stick to your recommandation with these new info?
Will I get much trebble loss by not using a 105db tweeter? Or should I hold this as requierment, go for horns and saw the hole to fit horns inside?
@Moondog55, nope, no 6,3mm jack, only XLR male and female.
And here enclosed, the other side of the board for your curiosity, with the "model number" (I guess) ERCEE FI-86 on the left.
Do you guys have some special recommendation/advice regarding the last steps of the restauration? Like should I kick this bulb as I'm changing the tweeter? Should I change the wires?
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Glad you found the Ciare 🙂
That said, in general domes are fragile for PA use.
Since you seem to be decided to repair it for good and apparently drive it hard 😉 , maybe you should just upgrade to real PA type horn tweeters.
Are you in Europe or USA?
If USA, best option (although not exactly inexpensive) could be:
https://www.parts-express.com/Eminence-APT-80-Super-Tweeter-with-80-Conical-Horn-290-532
guaranteed PA level power, robust, LOUD.
If in Europe, search catalogs from Monacor, Ciare (why not?), RCF, Faital Pro, etc .for equivalnt high power and sensitivity tweeters, most will be horn loaded.
Even a Bullet tweeter might do, but they typically require high crossover frequency, not sure about that Ciare X-over, maybe you can draw its schematic yourself and post it here?
Only a few parts involved, and quite a few X-over experts here, they might analyze it for you.
That said, in general domes are fragile for PA use.
Since you seem to be decided to repair it for good and apparently drive it hard 😉 , maybe you should just upgrade to real PA type horn tweeters.
Are you in Europe or USA?
If USA, best option (although not exactly inexpensive) could be:
https://www.parts-express.com/Eminence-APT-80-Super-Tweeter-with-80-Conical-Horn-290-532
guaranteed PA level power, robust, LOUD.
If in Europe, search catalogs from Monacor, Ciare (why not?), RCF, Faital Pro, etc .for equivalnt high power and sensitivity tweeters, most will be horn loaded.
Even a Bullet tweeter might do, but they typically require high crossover frequency, not sure about that Ciare X-over, maybe you can draw its schematic yourself and post it here?
Only a few parts involved, and quite a few X-over experts here, they might analyze it for you.
I've seen bulbs light up the inside of a rented speaker when a DJ pushed the mixer levels to maximum and there wasn't any limiter in the system. So I'd vote to keep the protection bulbs, unless you go with the nuclear bomb-proof tweeter option and install cheap piezo tweeters.
As for sensitivity, since the other drivers are unlikely to be anywhere near 105 dB, the tweeter would have been padded down at least 6 dB, which (if I'm counting on my fingers correctly) quadruples power handling. So a less sensitive tweeter might not be an improvement in power handling. But if you did install less sensitive tweeters, you should be able to balance the treble using the L-pad.
"ERCEE FI_86" might have been added by the board manufacturer to identify the job. It doesn't match the other lettering on the board, and looks computer plotted rather than rub-down Letraset like cavemen used. So, I'll revise my estimate to 1986 and up.
It might be good to make sure the other drivers are healthy before spending money on new parts. Drive each speaker with a sine wave at a moderate volume and slowly sweep it from 20 Hz up and listen for buzzes or whines.
As for sensitivity, since the other drivers are unlikely to be anywhere near 105 dB, the tweeter would have been padded down at least 6 dB, which (if I'm counting on my fingers correctly) quadruples power handling. So a less sensitive tweeter might not be an improvement in power handling. But if you did install less sensitive tweeters, you should be able to balance the treble using the L-pad.
"ERCEE FI_86" might have been added by the board manufacturer to identify the job. It doesn't match the other lettering on the board, and looks computer plotted rather than rub-down Letraset like cavemen used. So, I'll revise my estimate to 1986 and up.
It might be good to make sure the other drivers are healthy before spending money on new parts. Drive each speaker with a sine wave at a moderate volume and slowly sweep it from 20 Hz up and listen for buzzes or whines.
Sorry guys, I just fell sick and finally could reach my workshop today.
@JMFahey , Yeah, I'm in Europe and I was planning to order something on Monacor. From what I see, my two main/only options would be the MHD-190 (I need to recut the hole but anyway, however with only 25w I fear it might blow also), or the MDH-240 (which is 5mm too deep, but well, at this point I can laser cut an mdf support). The mhd-220n-rd could be an intermediary option (but I'll need a support plate also, because the whole is too wide).
What would be your advice on this last point? I guess it's more or less the last step before I can proceed to rebuilding it.
I tried to do some math for the crossover the but without statistics on the coil it looked like a pain. I'll post the pics here in case someone feels like redrawing it but I don't have the time these days (I've so much to catch up with...).
@dangus Alright, I'll keep the bulb! And yeah, I just recieved two new L-Pads as the others blew... I tested the other drivers, not very throughtfully and just by ear, but I made a few checks with music and slow sweeps.
@JMFahey , Yeah, I'm in Europe and I was planning to order something on Monacor. From what I see, my two main/only options would be the MHD-190 (I need to recut the hole but anyway, however with only 25w I fear it might blow also), or the MDH-240 (which is 5mm too deep, but well, at this point I can laser cut an mdf support). The mhd-220n-rd could be an intermediary option (but I'll need a support plate also, because the whole is too wide).
What would be your advice on this last point? I guess it's more or less the last step before I can proceed to rebuilding it.
I tried to do some math for the crossover the but without statistics on the coil it looked like a pain. I'll post the pics here in case someone feels like redrawing it but I don't have the time these days (I've so much to catch up with...).
@dangus Alright, I'll keep the bulb! And yeah, I just recieved two new L-Pads as the others blew... I tested the other drivers, not very throughtfully and just by ear, but I made a few checks with music and slow sweeps.
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Looks like a 3rd-order crossover (18dB/octave) which provides good protection from low frequencies. Ideally the mid would also have a 3rd order low-pass.
After staring at the BAXON board, scribbling in components using Irfanview, and realizing that G and A are "grave" (low) and "aigu" (high), the woofer has a 2nd order low-pass, and the midrange has a 2nd order high-pass filter. So the midrange has no low-pass at all, and will overlap with the tweeter. Also, no Zobel network for woofer and midrange to compensate for voice coil inductance and help the crossover to work better.
If one had a junkbox of crossover components handy and some clip leads, it would be interesting to add Zobels to the woofer and midrange, and a 2nd or 3rd order low-pass to the midrange, and see if that makes an audible or measurable improvement.
After staring at the BAXON board, scribbling in components using Irfanview, and realizing that G and A are "grave" (low) and "aigu" (high), the woofer has a 2nd order low-pass, and the midrange has a 2nd order high-pass filter. So the midrange has no low-pass at all, and will overlap with the tweeter. Also, no Zobel network for woofer and midrange to compensate for voice coil inductance and help the crossover to work better.
If one had a junkbox of crossover components handy and some clip leads, it would be interesting to add Zobels to the woofer and midrange, and a 2nd or 3rd order low-pass to the midrange, and see if that makes an audible or measurable improvement.