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I have a driver that seems to be dead but want to make sure.
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A rolled up newspaper tube held against your ear and in front of a suspect driver can help. To be sure, though, a soldering iron to disconnect the leads and an ohm meter will tell you more. (The piezo the exception here as it's a capacitive load, not resistive.) If it still tests alright, but you don't hear anything, then connected to an amp at low level with a sig gen feeding it (free apps are available for smart phones) can help you test for one that might be binding in some odd way.
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Which driver are you suspecting?
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The 5" midrange cone, which should be pretty obvious, right?
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That cone operates in the midbass and low midrange frequencies, which can be difficult to localize. Given that there's a fair bit of crossover between it and the woofer, it's understandable that it'd be hard to tell if it's making sound or not. More the expected. You can play the speakers and lightly rest your finger tips on the cone. You should feel it vibrating if it's working.
If not or only barely perceptibly (from sympathetic resonance), then you'll want to pull it and measure it. The AD5060/W8 has a failure mode that's a bit obscure. There's a joint between the tinsels and the voice coil leads that meet on the front of the cone and that spot where they're overlapped is prone to losing connection. The voice coil will be fine, but it'll still measure open because of that. You'll want to measure the DC resistance of the driver removed from the crossover if you've determined it's at fault. If open, scrape at a little bit of the lacquer at either end of those joints and measure the resistance across them to see if there's continuity or not. If not, scrape the rest of the paint away and lightly touch them up with solder and see if that fixes it. I've encountered this on one and I know someone else has as well. So, it's something to look for.
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In case I can't make that determination, is there a generally agreed upon comparable replacement?
On Sat, Oct 31, 2020 at 5:41 PM John van Son < jpvanson@...> wrote: That cone operates in the midbass and low midrange frequencies, which can be difficult to localize. Given that there's a fair bit of crossover between it and the woofer, it's understandable that it'd be hard to tell if it's making sound or not. More the expected. You can play the speakers and lightly rest your finger tips on the cone. You should feel it vibrating if it's working.
If not or only barely perceptibly (from sympathetic resonance), then you'll want to pull it and measure it. The AD5060/W8 has a failure mode that's a bit obscure. There's a joint between the tinsels and the voice coil leads that meet on the front of the cone and that spot where they're overlapped is prone to losing connection. The voice coil will be fine, but it'll still measure open because of that. You'll want to measure the DC resistance of the driver removed from the crossover if you've determined it's at fault. If open, scrape at a little bit of the lacquer at either end of those joints and measure the resistance across them to see if there's continuity or not. If not, scrape the rest of the paint away and lightly touch them up with solder and see if that fixes it. I've encountered this on one and I know someone else has as well. So, it's something to look for.
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Find a used one. I think I have two of that board.
In case I can't make that determination, is there a generally agreed upon comparable replacement?
On Sat, Oct 31, 2020 at 5:41 PM John van Son < jpvanson@...> wrote: That cone operates in the midbass and low midrange frequencies, which can be difficult to localize. Given that there's a fair bit of crossover between it and the woofer, it's understandable that it'd be hard to tell if it's making sound or not. More the expected. You can play the speakers and lightly rest your finger tips on the cone. You should feel it vibrating if it's working.
If not or only barely perceptibly (from sympathetic resonance), then you'll want to pull it and measure it. The AD5060/W8 has a failure mode that's a bit obscure. There's a joint between the tinsels and the voice coil leads that meet on the front of the cone and that spot where they're overlapped is prone to losing connection. The voice coil will be fine, but it'll still measure open because of that. You'll want to measure the DC resistance of the driver removed from the crossover if you've determined it's at fault. If open, scrape at a little bit of the lacquer at either end of those joints and measure the resistance across them to see if there's continuity or not. If not, scrape the rest of the paint away and lightly touch them up with solder and see if that fixes it. I've encountered this on one and I know someone else has as well. So, it's something to look for.
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There are currently 5 of them on Ebay right now.?
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I can definitely hear the "working" driver in the other speaker, and I tried different program material to eliminate the chance it's just the recording. I agree that finding a used one is the best alternative to keep them matched and "pure."
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Are yours mirrored or not? Which side do u need if mirrored. Easier to replace the boards on that side rather then removing driver? Some of them are glued in not just screwed?
I can definitely hear the "working" driver in the other speaker, and I tried different program material to eliminate the chance it's just the recording. I agree that finding a used one is the best alternative to keep them matched and "pure."
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AD5060/W8, B&O also used that driver.
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MIrrored pair, its the left speaker.
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Have you isolated the driver, as in taken the leads off the driver and tested the driver out of the crossover?? If you did and I missed it, my apologies, it is just those Philips drivers are fairly robust in this application and I would expect a blown cap before
a blown driver.
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MIrrored pair, its the left speaker.
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If you do want to attempt a repair, you'd be looking at the overlapped tinsels here:
For replacement, as the others have mentioned, you can picked up a used example. The Philips AD5060/W8 was used in many models by many brands. Just be sure you're getting the W8, not the 4ohm W4, and not the M8 (whizzer cone) or SQ8 (back cup). Also, be sure to look closely at the surrounds. By this point, the old rubber has hardened on all of these and may have cracked and split by now as is the case with many. Stiff surrounds means they won't sound as new, but will work well enough and likely match your other unit, but cracked or split means you'd be better off looking for some in usable condition. The photo I shared above is a unit suffering from aged rubber surrounds, the sure signs of which are a flattening of the original curve, the lateral splits and longitudinal splits around the cone's edge.
When you make the replacement, take care with the backing felt. That must be there to provide acoustic resistance and damping or the speakers will not sound right. (Seen a few where it was torn off and tossed. Not good.)
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I've been looking at a few on eBay and they have the split surrounds (or near split) so I'll pay close attention.
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I got two from this seller and they were perfect, soft and pliable surrounds.? His communication was excellent as well so ask about the surround condition if it isn't a crossover issue.
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The speaker has been tested for continuity and the ohms read around 7.
www.ebay.com
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From: DahlquistSpeakers@groups.io <DahlquistSpeakers@groups.io> on behalf of w e <sky27709@...>
Sent: Sunday, November 1, 2020 9:14 AM
To: DahlquistSpeakers@groups.io <DahlquistSpeakers@groups.io>
Subject: Re: [DahlquistSpeakers] Is the Binks tool designed to isolate speakers that aren't working?
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I've been looking at a few on eBay and they have the split surrounds (or near split) so I'll pay close attention.
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Some specs of the Philips AD 5060/Sq 8 (1980 price in French francs...)
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All part of the frustration with vintage drivers. Everything is suffering age related degradation regardless of materials, so you have to be extra careful to get something not obviously degraded. Then there's the other issue of how they've been treated by the seller. Too many think you can "fix" stiff rubber surrounds with brake fluid, ArmorAll, etc and end up with something that's half melted and far out of spec. If it seems too soft and pliable, it may not have the intended designed compliance. The aging of rubber cannot be reversed with magic elixirs, unfortunately. Once the plasticizers migrate out, the long chain polymers break and the rubber starts crystalizing, that's it. Anything that softens it is just acting as a solvent and doing more harm than good. So, if you see something that does look good, make sure there's no mention in the description of having been 'freshened up', 'surrounds treated with...', etc or it won't be what the design calls for. You'll also need to be careful about the age. The first 1200 or so DQ-10s used the earlier production AD5060/W8s with the dusky orange dust cap. These actually have different specs (lower Fs, etc) than the later production with the darker dustcaps. While they might be within tolerance, especially with age stiffening their surrounds, they may also be too far out. The DQ-10s these were used with had fairly different crossovers in the bass legs that included them. Also, be absolutely sure you're getting /W8s. Philips number scheme was such that very different types of drivers would have the same initial numbers with the differentiation coming with those last two characters. The numbers before just indicated frame size and magnet material. So, AD5060/SQ8s cannot be substituted for AD5060/W8s. They're very different drivers. The latter that you're looking for is a woofer, the other a midrange. The AD5060/M8, in turn, is a full-range driver and, again, very different parameters. You need the AD5060/W8 with these specs:? /g/DahlquistSpeakers/wiki/23812The Philips driver numbering scheme, for reference: 
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