Infinity Quantum 3 help
- Thread starter quantum 3
- Start date
Kencat
Super Member
quantum 3 said:
Bill, how did the refoam go? Did you shim the VC or ???? Would be neat to hear how you did it and whether you thought they were easy to do etc.
quantum 3 said:
Definitely the ultimate would be to have a set of the originals. Have you been keeping an eye on the auction site(s) and even here on AK? (nevermind, looking at your later posts...you are watching for sure....any luck though?)
I saw somewhere where it was said that the dome mids were Peerless
A very similar dome can be seen on some of the older ADS speakers. quantum 3 said:
While you are looking for the originals, getting an interim pair would be cool to get the speakers up and running. You'll want to make sure you are matching the impedance of the original mids. I haven't had any of mine out of the cab to measure DCR individually, but the two of them together measure about 4 Ohms, so if they are in parallel each could be 8 Ohm. I'ld wait for a positive reponse on this though before buying. You could test the replacement one you have to see what it measures, but whether that is per original could be suspect as well.
Bill, you may be the leader on this replacement project. I'm sure as time takes it's toll on the tinsel leads of these old Quantum speakers, others will be looking for a sonically equivalent dome replacement as well. Keep us all posted on your progress/experimentation.
Last edited:
quantum 3
Active Member
Hi Ken,
The re-foam went pretty good, messy and it drying time was slower than I figured, but all in all I think it is a success. I did shim the vc per the instructions and DVD they sent. It seemed like a logical thing to do, and was really easy.
I've been watching the ebay auctions, missing out so far... a few more up there now, so I am hopeful! I did find out I can buy them new for $135 each! But I'm hoping for a more modest purchase price. We'll see...
Thanks for the interest, advice, and encouragement! I'll keep updating as progress occurs!
Best,
\bh
The re-foam went pretty good, messy and it drying time was slower than I figured, but all in all I think it is a success. I did shim the vc per the instructions and DVD they sent. It seemed like a logical thing to do, and was really easy.
I've been watching the ebay auctions, missing out so far... a few more up there now, so I am hopeful! I did find out I can buy them new for $135 each! But I'm hoping for a more modest purchase price. We'll see...
Thanks for the interest, advice, and encouragement! I'll keep updating as progress occurs!
Best,
\bh
Kencat
Super Member
quantum 3 said:
What,what pardon? You can buy the mids new? Exact same PN ?
How? Where? I know 135$ is very steep but....these are a very delicate driver. I would probably have trouble dropping that kind of change right now too, but given the circumstances it might be worth it. Also, the info might help another reader who has the money to burn. On the plus side, it may help save a Quantum from the Partingout disease.
quantum 3
Active Member
Yep... from Harman directly. This is sort of my litmus test for price I'll pay on auction; knowing that for about $300 I can get a NOS pair of midrange domes and get these beasts running.
That being said, a perfectly functional pair (of Quantum 3s with all speakers working that is - but needing refoam on the woofers) sold last night on ebay for $250!
So, I hesitate, not really knowing the value of my curbside find should I ever want out of them, so to speak... right now I only have about $40 in them (badges and re-foam kit), and expect I'll pay at least another $150 for mids if I am lucky, more like $300 (with shipping) if not so lucky and buy the NOS from Harman, and still want to build some grills.
I just don't want to end up being upsidedown on them, if you catch my meaning... but if they sound as good as I hope, it's an investment in keepers, and a moot point!
\bh
email from Harman:
Hello,
Thank you for your inquiry about the availability of one of our parts.
The part is available:
The part is called: Mid Range
The Part # is: 902-0206
The price is $131.64 each, plus shipping and handling.
Please add tax if you live in New York, California, Florida, Arizona, New Jersey or North Carolina.
That being said, a perfectly functional pair (of Quantum 3s with all speakers working that is - but needing refoam on the woofers) sold last night on ebay for $250!
So, I hesitate, not really knowing the value of my curbside find should I ever want out of them, so to speak... right now I only have about $40 in them (badges and re-foam kit), and expect I'll pay at least another $150 for mids if I am lucky, more like $300 (with shipping) if not so lucky and buy the NOS from Harman, and still want to build some grills.
I just don't want to end up being upsidedown on them, if you catch my meaning... but if they sound as good as I hope, it's an investment in keepers, and a moot point!
\bh
email from Harman:
Hello,
Thank you for your inquiry about the availability of one of our parts.
The part is available:
The part is called: Mid Range
The Part # is: 902-0206
The price is $131.64 each, plus shipping and handling.
Please add tax if you live in New York, California, Florida, Arizona, New Jersey or North Carolina.
Q3's
Hi Q3,
Could I have your contact for the mid speakers from H K if you don't mind? I have 4 Q3's and 2 Q5's, 4 of the mids are bad and am slowly replacing/fixing them. These speakers really sound great when they are working fully. :thmbsp: I bought my first pair in 1978 and still have them. :yes:
Are these actually new replacements? same speakers?
John
Hi Q3,
Could I have your contact for the mid speakers from H K if you don't mind? I have 4 Q3's and 2 Q5's, 4 of the mids are bad and am slowly replacing/fixing them. These speakers really sound great when they are working fully. :thmbsp: I bought my first pair in 1978 and still have them. :yes:
Are these actually new replacements? same speakers?
John
Last edited:
quantum 3
Active Member
Belated Quantum 3 update
I have located one replacement midrange dome, it is installed and sounds awesome! Now I really notice how bad the non-original midrange sounds by comparison! So, I'm thinking of trying the microscopic tinsel repair on the other, but mine is broken almost flush at the dust cover... There is nothing visible to tack to. I guess I can try and hope the flux/silver seeps in and make contact?
Another question though, could I not remove the dust cap and replace both tinsel leads and install a new cap? Or are the caps rare too? Seems I could prime the two leads on that end, reinstall the cap, then fix the leads into the channel? Is my logic flawed?
Last, is there a reason this tinsel must be used, rather than a more sturdy stock or gauge of wire? I am guessing the answer will be yes, but not sure why?
Thanks folks!
\bh
I have located one replacement midrange dome, it is installed and sounds awesome! Now I really notice how bad the non-original midrange sounds by comparison! So, I'm thinking of trying the microscopic tinsel repair on the other, but mine is broken almost flush at the dust cover... There is nothing visible to tack to. I guess I can try and hope the flux/silver seeps in and make contact?
Another question though, could I not remove the dust cap and replace both tinsel leads and install a new cap? Or are the caps rare too? Seems I could prime the two leads on that end, reinstall the cap, then fix the leads into the channel? Is my logic flawed?
Last, is there a reason this tinsel must be used, rather than a more sturdy stock or gauge of wire? I am guessing the answer will be yes, but not sure why?
Thanks folks!
\bh
Charivari said:
Charivari
Fighting Naïve Realism
Advanced Quantum Midrange Dome Tinsel Replacement
As to how to do the tinsel replacement, not repair, much of the story is the same as my other post on patching these drivers. However, in many ways tinsel replacement is easier, which is good considering its necessity when the tinsel is broken right at the dome.
The tools you’ll need are as follows: a low wattage iron with a fine point tip – I use a cheap 15 watt Radio Shack special with the fine point that I’ve filed to be finer and cut a small groove in like a fountain pen to hold a solder drop where
I want it, a good pair of sharp, fine dikes/side cutters/ or whatever you call them, a pair of locking hemostats (sometimes called clamps or roach clips if you’re a child of the ‘60s/’70s), a magnifier lamp on a swing arm (its hard to make do with just a regular swing arm lamp and uncorrected vision as I do), and a sharp knife with a good handle and a short blade – keep a decent whetstone on hand as its easier if you keep sharpening the tip as it dulls in use during the repair. For materials, I use regular magnet wire that’s ~36 gauge I believe, 240 grit sandpaper to sand the enamel off the ends of the wire before soldering, solder tip cleaner (just makes it easier to keep the solder drop on the tip where you need it), flux and silver solder.
For preparation of the driver for repair, remove the four screws holding the face plate to the magnet and gently pull the dome straight out to keep from buggering the voice coil. Leave the foam plug in the hole in the center of the magnet and put the whole thing in a new sandwich bag and seal to keep from accidentally getting filings into the VC gap. Put the screws and washers someplace where you won’t lose them and watch out for the silver washers, they’ll want to stay in place at first, but may fall out during repairs and roll off the face of the Earth. Fortunately, the VC on these midranges are shorter than the plastic ring on the back of the face plate that helps align the magnet during assembly (I think). So, if you’ll bed the connection tabs back, you can set the whole front plate right on your workbench without messing up the VC (big, big pita with the Dahlquist driver for though similar, the VC was longer requiring me to tape a roll of masking tape onto the back to hold it up off the surface and relatively secure – you’ll need something like this for when you work on the back, though).
Now that you have the face plate with the dome before you, swing your lamp down for good light, sharpen your knife, and dig in. The channel where the wire leads from where it’s soldered to the connector tabs (the round depression on the front) is square bottomed and should have the resin dug out of for future replacement by something. Typically, the tinsel wire is wedged into one of these corners and just for the heck of it I like to remove it with all the rest of the old resin (mostly hard and will come up in shavings, but in the round depression is typically a little rubbery for some reason). Be careful to pull the knife tip out from the dome rather than push lest you slip and slice the dome in half. Where the channel ends, the resin is typically piled up a little bit to support where the tinsel goes out into free air to meet the dome. You can use the side cutters to cut this down relatively flat to easier tackle with the knife. Sharpen the tip as needed, for it dulls quickly (at least with my cheap Swiss Army knife, but not as fast as the scalpel dulled that I used initially) and sharper makes it easier.
When done, get the knife tip back ¼” as sharp as you can. Pick up the top plate and place your finger tip inside the dome supporting the fabric where the tinsel enters – try not to press too hard lest you deform the VC nearby or break it’s lead underneath. Very carefully bring the blade tip up along the fabric and pry/cut the resin off while approaching from several angles. This isn’t difficult or time consuming, but you do want a steady hand lest you slide the dome (fairly resilient and the resin will go before the fabric, but just in case …). I’ve considered using some solvent to make better work of this, but nothing seems to work. I’ve found that tetrahydrofuran (read the warnings and be careful) softens it up enough to be scraped away easily, unlike all the other solvents I’ve tried, but not to the degree to allow dabbing removal with a cotton swab. When that’s all cleaned up, take a sewing needle or a pin and prick a small hole in the dome near where the old tinsel entered. The needle is easier as you can roll it in your finger tips to drill a hole through the coating that stiffens the fabric without risking deforming the dome by pushing too hard.
Now, turn the front plate over and figure some way to secure it so that while pressing down or rough handling the dome you won’t smash it in too badly or break the other tinsel. For simplicity’s sake, I electrical taped a roll of masking tape around the dome to provide a firm surface while protecting the rest. Now, on the inside of the dome, you’ll see the tinsel wire glued to the fabric with more of that resin in a little loop before it heads up to the VC wires and joins up with them. Here you’ll prepare a little section of the loop for soldering using the process mentioned in the “Quantum 5 midrange help” thread I linked to earlier. Tin the bare metal and be sure to scrape away enough of the resin that it won’t flow over the tinned spot preventing soldering, but not so much that the wire comes free – it’ll break far, far too easily that way.
Take a ~6” length of magnet wire, long enough you have plenty to compensate for any mistakes, but not so long as to get tangled on everything. Take a little square of your sandpaper, fold it in half, and sand the enamel off 1/16” of the end by pinching the paper over it and pulling off the end, repeat. Add a hair of rosin to the bare copper here and tin it. When ready, take one of the ends and feed it through the needle/pin hole so that the tinned end remains inside the dome. Bend it just slightly so that the end will lay flat against the tinned portion of the dome VC. Use the linked to trick to wave a droplet of solder over the two to solder them wires together without melting the resin and forcing the need to scrape clean the tinned area. If need be, use the hemostats here to hold the wire in place, but do not lock them! If you do, it’s likely you’ll tear the connection apart or break the VC wire while trying to carefully unlock them (sliding teeth catch). Measure from the outside end of your replacement tinsel wire the resistance of the VC to the other tinsel’s connection tab. Make sure you’re measuring around 8 ohms so that you know your solder connection has good continuity and isn’t just pretending to be soldered while trapped in melted resin.
Before moving anything, very carefully apply something over the solder joint and the wire inside the dome so that it’s secured firmly to the fabric. Elsewise the loose wire could very well break when first playing music through your repaired dome or at the very least you’ll hear unpleasant rattling as the wire strikes the inside of the dome. The goop I’ve found to work fairly well is that little vial of clear liquid vinyl that comes with vinyl patch kits (for air mattresses and the like), it’s gooey enough to hold the wire well, but soft enough to flex with the dome. Be sparing, a little goes a long ways, but too much might add too much mass to the dome (you do have a little play room as the new tinsels are less massy than the old).
When the glue is set, flip the face plate back over and remove the tape roll or whatever else you used. Now, arc the magnet wire where it comes out of the dome into a similar shape and size as the original tinsel, lay the rest into the trough out to the solder tab spot to figure length and cut off the excess. Take your hemostats, lock them onto the wire to firmly secure it (to prevent stressing the solder connection inside the dome), and sand ~1/4” of the end of the wire free of enamel. Take your soldering iron and while holding the wire end down into that circular depression where I earlier mentioned the tinsel is secured to the connection tabs and solder it into place. Carefully lay the tinsel into the trough and figure out some way to secure it to prevent rattling. If you can find similar resin, great, pour that in there and coat the rest of the magnet wire to match the original. If not, take a short piece of electrical tape, fold it and press it into the channel securely over the wire using a flat bladed screwdriver of the back of you knife blade.
Carefully place the front plate over the magnet so that the VC goes into the magnet gap without and lateral torsion or scraping while eye-balling the screw holes so that they’re aligned with those in the front plate. When in place, loosely replace the screws and gently press with fingers on the surround roll of the dome nearest where the VC former is glued, press just a little bit in (<1/4”) and listen/feel for rub (slight hashing sound). If everything seems to be alright with no rub and the dome moves freely, tighten the screws, and recheck for rub.
Take your multimeter and in the resistance setting scrape the leads across the connection tabs. If the repairs worked, the driver will make a crackling sound. If it does, reinstall it while observing that the positive side of the driver marked by the orange dot is reconnected to the positive lead that was formerly removed from it, and enjoy the music.
If you have any further questions about the process, just ask. The whole process should take under 1.5 hours to 2 and only about an hour after you’ve had a little practice.
I wonder if I set a record for the most number of mentions of the word “tinsel” in one post? :scratch2:
Good luck,
- JP
Unfortunately, that’s not possible. You must have a goodly sliver of exposed wire to solder to and do so very carefully and quickly without overheating the tinsel and its coating. For, if you hope to let the solder flow or are too slow, that blasted orange-brown resin melts just enough to cover the wire over again and prevent it from sticking. Yes, it can be very frustrating. However, I’ve developed a new trick that’s just a hair easier when dealing with tinsels broken off right at the dome that I’ll discuss below.Quantum3 said:
No to the first and yes to the second. The dome of the midrange is not a dustcap, but the whole of the driver. What you speak of is the dome driver equivalent of a reconing. You see, this dome is shaped fabric of which the surround is a continuation of the same material. The edges are then glued to the face plate with a flat metal ‘washer’ glued over that edge to provide greater hold and a firm surface to butt against the magnet. At the fold that visually divides the two is glued the aluminum former about which the magnet wire (standard very fine gauge copper with an enamel coating) is wound. To attempt to remove the dome would mean the removal of the voice coil of which a replacement would need to be an exact match. Thus, to do as you suggest would need a special kit that a professional might utilize for such a replacement. The kits are not available for these drivers, as I learned when I walked the same path early on in my quest to find a means to repair these drivers with the broken tinsels.Quantum 3 said:
Not at all, I did a variant to repair one completely missing tinsel on one of the midrange domes in my Dahlquist DQ-10s that was successful (no audible difference betwixt the original and repaired drivers). Just a few minutes ago, I accomplished the same feat with two missing tinsels on the shot midrange dome that came with my new Quantum 2 cabinet during my mirror-imaging project to test the validity of the process on this driver so I could tell you if it would work or not. It wasn’t wholly selfless, a few days back a visiting friend walked into one of my Quantum 2s breaking anew the tinsel on one of my repaired domes. Amazingly, it wasn’t the patched section, but the original intact tinsel section that broke. Anyways, I needed to repair one to get these back up to par and your post just gave me the excuse.Quantum 3 said:
Answer will be yes? Well, only sorta. It would seem that the tinsels encased in their heavy adamantine coating of that infamous orange-brown resin would add mass and stiffness to the compliance of the dome. I suspect this much the case, but in preliminary listening, I haven’t heard a different between the originals and my repairs. Power handling is likely lower with a repaired driver, though. I’m currently looking for some replacement substance to coat my new tinsels with to simulate the originals more accurately. When I find something, I’ll let you know.Quantum 3 said:
As to how to do the tinsel replacement, not repair, much of the story is the same as my other post on patching these drivers. However, in many ways tinsel replacement is easier, which is good considering its necessity when the tinsel is broken right at the dome.
The tools you’ll need are as follows: a low wattage iron with a fine point tip – I use a cheap 15 watt Radio Shack special with the fine point that I’ve filed to be finer and cut a small groove in like a fountain pen to hold a solder drop where
I want it, a good pair of sharp, fine dikes/side cutters/ or whatever you call them, a pair of locking hemostats (sometimes called clamps or roach clips if you’re a child of the ‘60s/’70s), a magnifier lamp on a swing arm (its hard to make do with just a regular swing arm lamp and uncorrected vision as I do), and a sharp knife with a good handle and a short blade – keep a decent whetstone on hand as its easier if you keep sharpening the tip as it dulls in use during the repair. For materials, I use regular magnet wire that’s ~36 gauge I believe, 240 grit sandpaper to sand the enamel off the ends of the wire before soldering, solder tip cleaner (just makes it easier to keep the solder drop on the tip where you need it), flux and silver solder.
For preparation of the driver for repair, remove the four screws holding the face plate to the magnet and gently pull the dome straight out to keep from buggering the voice coil. Leave the foam plug in the hole in the center of the magnet and put the whole thing in a new sandwich bag and seal to keep from accidentally getting filings into the VC gap. Put the screws and washers someplace where you won’t lose them and watch out for the silver washers, they’ll want to stay in place at first, but may fall out during repairs and roll off the face of the Earth. Fortunately, the VC on these midranges are shorter than the plastic ring on the back of the face plate that helps align the magnet during assembly (I think). So, if you’ll bed the connection tabs back, you can set the whole front plate right on your workbench without messing up the VC (big, big pita with the Dahlquist driver for though similar, the VC was longer requiring me to tape a roll of masking tape onto the back to hold it up off the surface and relatively secure – you’ll need something like this for when you work on the back, though).
Now that you have the face plate with the dome before you, swing your lamp down for good light, sharpen your knife, and dig in. The channel where the wire leads from where it’s soldered to the connector tabs (the round depression on the front) is square bottomed and should have the resin dug out of for future replacement by something. Typically, the tinsel wire is wedged into one of these corners and just for the heck of it I like to remove it with all the rest of the old resin (mostly hard and will come up in shavings, but in the round depression is typically a little rubbery for some reason). Be careful to pull the knife tip out from the dome rather than push lest you slip and slice the dome in half. Where the channel ends, the resin is typically piled up a little bit to support where the tinsel goes out into free air to meet the dome. You can use the side cutters to cut this down relatively flat to easier tackle with the knife. Sharpen the tip as needed, for it dulls quickly (at least with my cheap Swiss Army knife, but not as fast as the scalpel dulled that I used initially) and sharper makes it easier.
When done, get the knife tip back ¼” as sharp as you can. Pick up the top plate and place your finger tip inside the dome supporting the fabric where the tinsel enters – try not to press too hard lest you deform the VC nearby or break it’s lead underneath. Very carefully bring the blade tip up along the fabric and pry/cut the resin off while approaching from several angles. This isn’t difficult or time consuming, but you do want a steady hand lest you slide the dome (fairly resilient and the resin will go before the fabric, but just in case …). I’ve considered using some solvent to make better work of this, but nothing seems to work. I’ve found that tetrahydrofuran (read the warnings and be careful) softens it up enough to be scraped away easily, unlike all the other solvents I’ve tried, but not to the degree to allow dabbing removal with a cotton swab. When that’s all cleaned up, take a sewing needle or a pin and prick a small hole in the dome near where the old tinsel entered. The needle is easier as you can roll it in your finger tips to drill a hole through the coating that stiffens the fabric without risking deforming the dome by pushing too hard.
Now, turn the front plate over and figure some way to secure it so that while pressing down or rough handling the dome you won’t smash it in too badly or break the other tinsel. For simplicity’s sake, I electrical taped a roll of masking tape around the dome to provide a firm surface while protecting the rest. Now, on the inside of the dome, you’ll see the tinsel wire glued to the fabric with more of that resin in a little loop before it heads up to the VC wires and joins up with them. Here you’ll prepare a little section of the loop for soldering using the process mentioned in the “Quantum 5 midrange help” thread I linked to earlier. Tin the bare metal and be sure to scrape away enough of the resin that it won’t flow over the tinned spot preventing soldering, but not so much that the wire comes free – it’ll break far, far too easily that way.
Take a ~6” length of magnet wire, long enough you have plenty to compensate for any mistakes, but not so long as to get tangled on everything. Take a little square of your sandpaper, fold it in half, and sand the enamel off 1/16” of the end by pinching the paper over it and pulling off the end, repeat. Add a hair of rosin to the bare copper here and tin it. When ready, take one of the ends and feed it through the needle/pin hole so that the tinned end remains inside the dome. Bend it just slightly so that the end will lay flat against the tinned portion of the dome VC. Use the linked to trick to wave a droplet of solder over the two to solder them wires together without melting the resin and forcing the need to scrape clean the tinned area. If need be, use the hemostats here to hold the wire in place, but do not lock them! If you do, it’s likely you’ll tear the connection apart or break the VC wire while trying to carefully unlock them (sliding teeth catch). Measure from the outside end of your replacement tinsel wire the resistance of the VC to the other tinsel’s connection tab. Make sure you’re measuring around 8 ohms so that you know your solder connection has good continuity and isn’t just pretending to be soldered while trapped in melted resin.
Before moving anything, very carefully apply something over the solder joint and the wire inside the dome so that it’s secured firmly to the fabric. Elsewise the loose wire could very well break when first playing music through your repaired dome or at the very least you’ll hear unpleasant rattling as the wire strikes the inside of the dome. The goop I’ve found to work fairly well is that little vial of clear liquid vinyl that comes with vinyl patch kits (for air mattresses and the like), it’s gooey enough to hold the wire well, but soft enough to flex with the dome. Be sparing, a little goes a long ways, but too much might add too much mass to the dome (you do have a little play room as the new tinsels are less massy than the old).
When the glue is set, flip the face plate back over and remove the tape roll or whatever else you used. Now, arc the magnet wire where it comes out of the dome into a similar shape and size as the original tinsel, lay the rest into the trough out to the solder tab spot to figure length and cut off the excess. Take your hemostats, lock them onto the wire to firmly secure it (to prevent stressing the solder connection inside the dome), and sand ~1/4” of the end of the wire free of enamel. Take your soldering iron and while holding the wire end down into that circular depression where I earlier mentioned the tinsel is secured to the connection tabs and solder it into place. Carefully lay the tinsel into the trough and figure out some way to secure it to prevent rattling. If you can find similar resin, great, pour that in there and coat the rest of the magnet wire to match the original. If not, take a short piece of electrical tape, fold it and press it into the channel securely over the wire using a flat bladed screwdriver of the back of you knife blade.
Carefully place the front plate over the magnet so that the VC goes into the magnet gap without and lateral torsion or scraping while eye-balling the screw holes so that they’re aligned with those in the front plate. When in place, loosely replace the screws and gently press with fingers on the surround roll of the dome nearest where the VC former is glued, press just a little bit in (<1/4”) and listen/feel for rub (slight hashing sound). If everything seems to be alright with no rub and the dome moves freely, tighten the screws, and recheck for rub.
Take your multimeter and in the resistance setting scrape the leads across the connection tabs. If the repairs worked, the driver will make a crackling sound. If it does, reinstall it while observing that the positive side of the driver marked by the orange dot is reconnected to the positive lead that was formerly removed from it, and enjoy the music.
If you have any further questions about the process, just ask. The whole process should take under 1.5 hours to 2 and only about an hour after you’ve had a little practice.
I wonder if I set a record for the most number of mentions of the word “tinsel” in one post? :scratch2:
Good luck,
- JP
Charivari
Fighting Naïve Realism
Good luck, quantum 3. I hope you're successful in your repairs or at least that they'll hold until you can find an intact mid for a reasonable price.
Anyways, I was able to borrow a friend's digital camera for a little bit this weekend and snapped a couple of quick pics of the repaired drivers installed in their Quantum 2. Maybe the visual reference will be a little helpful?
Dual Tinsel Replacement:
Eventually I hope to find the appropriate resin to coat this tinsel and fill the groove as was the case with the originals. Suggestions?
Single Tinsel Patch:
Top tinsel is repaired via the old means -- ie, soldered to the tinsel stubs rather than a total replacement using 3 Sound King wire strands vs. magnet wire.
- JP
Anyways, I was able to borrow a friend's digital camera for a little bit this weekend and snapped a couple of quick pics of the repaired drivers installed in their Quantum 2. Maybe the visual reference will be a little helpful?
Dual Tinsel Replacement:
Eventually I hope to find the appropriate resin to coat this tinsel and fill the groove as was the case with the originals. Suggestions?
Single Tinsel Patch:
Top tinsel is repaired via the old means -- ie, soldered to the tinsel stubs rather than a total replacement using 3 Sound King wire strands vs. magnet wire.
- JP
Attachments
Last edited:
banffskiing
Active Member
JP
Great pictures, I think replacing the entire lead looks much cleaner. Just counted the number of domes that I need to repair. Looks like 11 total and the last one is questionable. Except for the wire, I have most of the materials needed to tackle the job. I will probably try to do 2 or 3 per week depending on how long it takes. Haven’t a chance to check the emits. Crossing my fingers that they are in good shape. Also took a quick peek at partsexpress and madissound and it looks like it might be hard to find some of the big electrolytics. I think some place like Mouser or Digikey will also have parts such as those.
Great pictures, I think replacing the entire lead looks much cleaner. Just counted the number of domes that I need to repair. Looks like 11 total and the last one is questionable. Except for the wire, I have most of the materials needed to tackle the job. I will probably try to do 2 or 3 per week depending on how long it takes. Haven’t a chance to check the emits. Crossing my fingers that they are in good shape. Also took a quick peek at partsexpress and madissound and it looks like it might be hard to find some of the big electrolytics. I think some place like Mouser or Digikey will also have parts such as those.
Charivari
Fighting Naïve Realism
Eleven domes? That leaves just one. What happened to these? I thought the seller, Bob, said that they were fully functional. You have a lot of work ahead of you on those, but by the third you should be able to fix a lead in under 20-30 mins and may get faster towards the end. It would take a lot of waiting and a lot of money to find intact originals on eBay, so it's worth the effort.
If the Mylar on the EMITs is not shredded (easily visible through the front of the tweeters), then you should be alright with those as the remaining possible damage is largely repairable. You can find links to posts on how to repair the three main problems with EMITs here.
The midbass driver that you've mentioned being bad should be easy to replace as it was used in many different speakers: the most notable being the Infinity Quantum series, of course, and the Dahlquist DQ-10. If you're impatient, Regnar repairs that driver, but at significant cost.
As to the large electrolytics, yes, you won't find caps of those values at those speaker builder suppliers. However, they are just generic electrolytics that need only be replaced with those of like value. Of course, you could also pick up a batch of smaller value caps and stack them to reach the needed value with no drawbacks. I have three Quantum 2 cabinets with crossovers, the earliest has a stack of the Callins non-polarized computer grade electrolytics, the second just one serial number off has a couple of large caps with smaller bypass caps to fill in the last of the value, and the third much later cab has single large caps of the appropriate value. So, however you can reach the capacitance, so long as the voltage rating is the same or higher, will work for the Watkins.
Good luck on your repairs. Any chance of photos showing your progress?
- JP
If the Mylar on the EMITs is not shredded (easily visible through the front of the tweeters), then you should be alright with those as the remaining possible damage is largely repairable. You can find links to posts on how to repair the three main problems with EMITs here.
The midbass driver that you've mentioned being bad should be easy to replace as it was used in many different speakers: the most notable being the Infinity Quantum series, of course, and the Dahlquist DQ-10. If you're impatient, Regnar repairs that driver, but at significant cost.
As to the large electrolytics, yes, you won't find caps of those values at those speaker builder suppliers. However, they are just generic electrolytics that need only be replaced with those of like value. Of course, you could also pick up a batch of smaller value caps and stack them to reach the needed value with no drawbacks. I have three Quantum 2 cabinets with crossovers, the earliest has a stack of the Callins non-polarized computer grade electrolytics, the second just one serial number off has a couple of large caps with smaller bypass caps to fill in the last of the value, and the third much later cab has single large caps of the appropriate value. So, however you can reach the capacitance, so long as the voltage rating is the same or higher, will work for the Watkins.
Good luck on your repairs. Any chance of photos showing your progress?
- JP
banffskiing
Active Member
JP
The emits look good from the front so I think they might be ok. And yes, we have a nice Digital Cam that I can take some photos with. I will post a few once I have a few of the mids repaired. Oh as for repairing the Mid bass, it is not the original driver so I must locate a pair of those. If you run across any let me know. I will take a photo of the of the cabinets with the grills in place and post it later tonight.
The emits look good from the front so I think they might be ok. And yes, we have a nice Digital Cam that I can take some photos with. I will post a few once I have a few of the mids repaired. Oh as for repairing the Mid bass, it is not the original driver so I must locate a pair of those. If you run across any let me know. I will take a photo of the of the cabinets with the grills in place and post it later tonight.
Charivari
Fighting Naïve Realism
I look forward to seeing the pictures. At the very least they would allow me to enjoy a pair of QLS-1s by proxy. :thmbsp:
- JP
Sure thing. There's a pair that look to be in great shape here. As I have both a pair of Quantum 2s and Dahlquist DQ-10s, I've been able to compare the drivers directly and they are the same. All the numbers except for the manufacture date match up.banffskiing said:
- JP
banffskiing
Active Member
Sorry, have the pic but can't figure out how to insert it.
Kencat
Super Member
banffskiing said:
Check this out. A JP tutorial. Excellent.
http://audiokarma.org/forums/showthread.php?t=43025
Last edited:
