Help restoring speakers

Trying to rebuild and restore a pair of JPW AP3 speakers.
The cabinets are in decent condition but I’ve found that one sounds great and the other sounds dull. I’m sure one tweeter in not operational and I think one of the big drivers is not working properly.
It seems a shame to bin them has anyone got tweeters or woofers for these collecting dust that could bring these back to life or any advice or help.
I think the same drivers are used in HB1’s as well.


The tweeters are still sold under the peerless brand, no idea about the woofers. Falcon might be worth an ask, worth changing what looks like an electrolytic cap there in the crossover too.

Think guy still sells the woofers

Yes the woofers can be sourced new and I think the tweeters can be as well.
If they were going to feature in my main system I would happily pay for new drivers but as I really only started trying to fix them up as a project for possible bake off use and perhaps to pass on to another enthusiast at some point I was hoping to source some used drivers to keep costs realistic.

How do I know which caps to buy to replace the ones in the crossovers? Not something I know much about.

I can only see one cap, the blue one, it will have a uf rating and a voltage rating. Get a nice polypropylene in a higher voltage (250-400v) and the same uf. Solens, Ansar supersounds, Clarity caps all good bets.

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Oh and try swapping the drivers between speakers, make sure its not a crossover or wiring fault.

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What is the value of the cap? I have some Russian paper in oils of various values spare, might have the right one

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Did this today to be sure it wasn’t a crossover issue, I’ll double check wiring but I’m pretty sure it is all sound.

I would wager a quarter muffin Guy may have some insight here

If it does use the same as the HB1 it’s the same driver as the Snell K in which case Scanspeak make a compatible one

Scanspeak M21WG-09-08

I did have some old vifa drivers from some Snell K’s but I think they were actually from a Snell J, will have a look and see if I still have them, if so they’re yours for postage if you want to try them.

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The Snell J’s bass driver was very different, designed for a ported box with a larger magnet. The K (& JPW) use a very particular woofer intended for sealed box use. Scanspeak do now make the M21 WG 09 08 in Vifa’s old factory on their tooling with their people.They are indistinguishable from the original ones. It does appear that your drivers have been re-foamed at some point (or at least the one you’ve showed has been). Difficult to gauge how well that’s been done ie how well centred the voice coil is in its gap or which surrounds were used.

I do usually have stock of M21’s but I’m just out & need to order some more. But I might have the odd one I’ll check. I think I do also have a few D19 tweeters (which incidentally is not the same one as was used by Heybrook in the HB1)

You can check the tweeter actually functions by detaching it from this circuit & carefully hold your speaker leads to the terminals while playing a signal at very low levels. Be careful not to short the output of your amp & keep the level very low as the tweeter doesn’t want to try playing bass at any significant level. But it’ll tell you if it’s working.


Can you guys help me identify these caps and advise what I need to buy to replace them.

to upload photos

Cap, singular. The white thing is a resistor, 2.4 Ohms, 5 Watt.

As far as the cap goes, it’s non-polarized, but no value is visible. You’d have to un-glue it.

The white squarish one is a wire wound resistor (2.4Ohms 5 W) the blue one is a capacitor but I can’t see the value, it maybe underneath?

If you want some of these bits over the weekend, Maplins or JPG Electronics in Chesterfield should have them.

Wouldn’t worry about changing the resistor though they are cheap enough.

Needs a Dueland cap though :slight_smile:

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A shocking lack of commitment

To get at the back of the cap to read the value you should be able to soften the glue by careful use of a hairdryer to warm everything up.

If the resistor’s in-series with the cap I’m not convinced that it’s doing much at so low a value, but I’m very much no Xover expert . . . Still, I wonder if a slightly lower value film cap would probably do enough to limit bandwidth and current to the tweeter.

Ignore Edd, those nasty-ass white coffins are death to resolution! :face_vomiting:

It looks like silicone, which is generally heat proof. I doubt the resistor is there to limit current. More likely padding level.

Changing the design without understanding it is not a good way forward.

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