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New score - Boston Acoustics A150s - Need Help!

efrance45

efrance45

Active Member
This weekend I saw a listing for a bunch of electronics for free, and noticed a pair of A150s (pretty sure series II) in one picture. Picked them up, and cosmetically they're in pretty solid shape! The vinyl veneer doesn't have any major scuffs or scratches, and the grills are in good shape (just one is missing a single peg). The bases are rough, but those are easily fixed. And one tweeter faceplate has a hairline crack, but you can't notice it much.

Brought them back to set up, and it seems like both woofers are blown. They rattle pretty badly, one much worse than the other. One I almost didn't notice the rattle/distortion until I listened to each driver up to my ear.
Pulled the woofers to test with a multimeter and they both read ~3.8ohms. The woofers were definitely refoamed, looks to be done improperly without the filleted foams. If the voice coils weren't properly centered, could that be what's wrong? If so, how do I test that?

Also - I know if the woofers are truly shot I should aim for factory replacements. Would the woofers from a series 1 A100 work, or no? I found a pair my brother could pick up with rough cabs that have been recently refoamed. They also have the round SEAS tweeter that I could sell to recoup cost and keep them nearly free (or keep it for future use!)8yLDxPmXToqvvXFKULmKZw.jpg .
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I would give a shot refoaming the woofers first, it looks like a pretty poor job. Don't play them until you get them done. You don't want to ruin the voice coils if they are out of alignment. Use the proper foams and a 30hz test tone to help center them. Boston Acoustics are usually one of the easier woofers to refoam.
 
colohiker said:
I would give a shot refoaming the woofers first, it looks like a pretty poor job. Don't play them until you get them done. You don't want to ruin the voice coils if they are out of alignment. Use the proper foams and a 30hz test tone to help center them. Boston Acoustics are usually one of the easier woofers to refoam.
Click to expand...
Strange the outer surrounds are there but inner woofer degraded ... it’s usually opposite
Refoaming sounds tough wonder what glue they use for that ?
 
efrance45 said:
This weekend I saw a listing for a bunch of electronics for free, and noticed a pair of A150s (pretty sure series II) in one picture. Picked them up, and cosmetically they're in pretty solid shape! The vinyl veneer doesn't have any major scuffs or scratches, and the grills are in good shape (just one is missing a single peg). The bases are rough, but those are easily fixed. And one tweeter faceplate has a hairline crack, but you can't notice it much.

Brought them back to set up, and it seems like both woofers are blown. They rattle pretty badly, one much worse than the other. One I almost didn't notice the rattle/distortion until I listened to each driver up to my ear.
Pulled the woofers to test with a multimeter and they both read ~3.8ohms. The woofers were definitely refoamed, looks to be done improperly without the filleted foams. If the voice coils weren't properly centered, could that be what's wrong? If so, how do I test that?

Also - I know if the woofers are truly shot I should aim for factory replacements. Would the woofers from a series 1 A100 work, or no? I found a pair my brother could pick up with rough cabs that have been recently refoamed. They also have the round SEAS tweeter that I could sell to recoup cost and keep them nearly free (or keep it for future use!)View attachment 2110188 .
View attachment 2110184 View attachment 2110185 View attachment 2110186 View attachment 2110187
Click to expand...
If they make noise, there's hope. Take off that foam carefully, and if you can move the cone up and down after it's off without rubbing, just refoam them properly and you're good to go.
If it always rubs, the voice coils are shot.
 
KingAzazel said:
Strange the outer surrounds are there but inner woofer degraded ... it’s usually opposite
Refoaming sounds tough wonder what glue they use for that ?
Click to expand...

Usually if you buy a surround refoaming kit from a reputable seller they'll include glue
 
ivandezande said:
If they make noise, there's hope. Take off that foam carefully, and if you can move the cone up and down after it's off without rubbing, just refoam them properly and you're good to go.
If it always rubs, the voice coils are shot.
Click to expand...

Thank you! I'll try that later today and report back. Do you have any idea if the Gen I A100 woofer would work?
 
I would think the A100 woofer and the 150 are the same one. The only difference between them was the added mid.

I would get another pair of BA woofers. The refoam may or may not be successful. I would hate to go thru all the time and expense to have the same issue a day week or even sooner pop backup.
 
I don’t know about interchangeability with other models but if it was me I would buy surrounds and give it another try. I may even have some foams left over I did so many of them. Just make sure you either shim or test tone center the woofer
 
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Oerets said:
I would think the A100 woofer and the 150 are the same one. The only difference between them was the added mid.

I would get another pair of BA woofers. The refoam may or may not be successful. I would hate to go thru all the time and expense to have the same issue a day week or even sooner pop backup.
Click to expand...

Yeah if I remove the current foams and the coils are still scratching I probably won't go through the effort to try a refoam. I'm just having trouble finding someone with some spare drivers
 
After I cut out some of the foams, would putting a 30hz test tone through the woofers tell me definitively if they're salvageable? I'll hook up a small amp and just use an online tone generator, having the woofers sitting cones up.
 
With any BA refoam I've done I've found that I could easily center the voice coil by hand just by lightly bouncing the cone up and down. Try that first.
 
Alright so I have a good start on removing the existing foam job.

Some of my thoughts...
I think I may only have one bad woofer. I took off the dust caps as well because they were crooked, and driver 1 (bad driver I think) could be centered pretty well by hand after a few tries, but still had a VERY faint bit of coil noise. No tactile grinding or anything horrible, but it sounds almost like a loose bit of vc is still shaking around when pressed. Guessing if its not easy to make it not make noise, its a bad driver??

Driver 2 (seemingly good driver) appears to be okay. I can move the cone by hand with no coil sound whatsoever, but I have a problem. I'll attach a picture soon - the glue between the driver and the metal piece that the voice coil wraps around is falling apart. I think that's why this woofer sounded okay initially before closer listening, but ended up being distorted. How can I fix this before hopefully attempting a refoam?
 
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Here are two close-ups of driver 2 (good driver)

The glue is completely cracked, and the cone can move freely from the voice coil assembly (some parts are still attached though). I'm guessing this may be a bit out of my wheelhouse since it seems more of a re-cone job?
 
homebrew said:
Have you gotten prices from places like Simply Speakers? Might be worth a try. Then you'll know it's done right.
Click to expand...

Sorry, just checked their reconing and refoaming prices - they're a bit too high for what I'm looking to put into these. It would probably cost just below $300. Thank you for the suggestion though!!
 
efrance45 said:
View attachment 2111006 View attachment 2111007
Here are two close-ups of driver 2 (good driver)

The glue is completely cracked, and the cone can move freely from the voice coil assembly (some parts are still attached though). I'm guessing this may be a bit out of my wheelhouse since it seems more of a re-cone job?
Click to expand...

If that woofer still has continuity- you might want to try shimming the voice coil, squaring up the cone so that it's as close to level at the edge (relative to the frame) as possible, and bonding the cone back to the coil with some epoxy. Then, refoam the woofer. It might be save-able. I've had probably about a 50% success rate, fixing that, in this fashion.

Regards,
Gordon.
 
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