Need help ID-ing this sub. T/S numbers too.

[Z1NONLY 10+ year member]

I helped a friend move and we came across this old sub. The surround was shot so he told me I could have it. I have since replaced the surround with a CV kit. The rest of the sub looks hardly used. (The voice coil and spider show no signs of stress.)

Don't let the orange re-foam throw you.

It's obviously a Boston acoustics sub but I can't find a model number or T/S numbers anywhere.

Click to read more...

 

[Z1NONLY 10+ year member]

dbl post

 

[The_Grimy_One 10+ year member]

IM sure some guru will know... Looks pretty old, but I could be wrong. Definitely looks like a descent sub.

 

[hispls 5,000+ posts]

IIRC the original PRO series used that shape basket. Either way in the olden days they made some really great sounding subs. Even their entry level stuff was pretty nice when they still manufactured up in Peabody.

 

[RAM_Designs 5,000+ posts]

Old school Boston 12.4lf...very nice subs, not sure how it'll sound with a random CV recone. The open space where you can see the tinsels soldered to the terminals is where there would be identifying markings on the original subs.

 

[bhsdriller 10+ year member]

funky pup recone

 

[Z1NONLY 10+ year member]

I only replaced the foam surround and center cap. (used a generic cap since the CV cap was too small) I don't know how it will sound either, but I'm 100% sure it will sound better than it did with the tales-from-the-crypt skeleton of a surround I found it with.

I was very careful to center the, large cross-drilled voice coil, when I reassembled it, so functionality should be ok. (Assuming it doesn't bottom out on my refoam..... Need to find T/S numbers)

 

[THATpurpleKUSH 5,000+ posts]

That sub is listed in the drivers that come pre loaded into win isd. It doesnt have all paramters but this is what I found:

qts: .25

vas: 136 L

fs: 32hz

would tsp's get changed after the new foam?

edit:

FS : Boston Acoustics 12.4LF subwoofer drive unit (pHing Classifieds)

Specs
Continuous Power 350 watts

Peak Input Power 700 watts

Sensitivity (1 watt .5m) 102dB

Nominal Impedance 4 Ohms

Fs 32 Hz

Vas 4.8cubic feet

Qts 0.25

Qes 0.25

Qms 10.25

Cms 327

Sd 84.8square inches

Voice Coil Diameter 2 in.

Re 3.3ohms

Le 0.57mH

X-max (one way) 3.4mm

 

[Z1NONLY 10+ year member]

Google isn't coming up with anything. I found an old thread of one guy selling one who claimed it was rated @102db 1w/.5m (so 96db 1w/1m?)

Anyone have a general guesstimate of the kind of enclosures this thing likes?

Oops I was typing while you were posting..

Thanks for the numbers.

BTW the CV foam kit came as a pair and I used the other surround to rehabilitate an ancient Rockford 12". It's running off of a meager 100w from an alpine amp in my daughters car. (ported enclosure) It plays low and rather loud for the little power it's getting. Back in the day, power was pricey and sensitivity was a lot more important.

The one in your pic looks like it has a parts express foam kit on it. With 3.5 mm Xmax, I'm sure both the parts express kit and the CV kit won't hold back it's motion.

If the surrounds weigh a lot more (or less) than the original, I'm sure it would throw the numbers off. However I expect the re-foamed sub to perform in the "ballpark" of the original. If I had gone with a massive, heavy, half-roll rubber surround I would expect a good bit of deviation from stock.

 

[THATpurpleKUSH 5,000+ posts]

If those tsp's from my edit are accurate, the ebp for that is 128, which strongly suggests a ported enclosure

 

[Z1NONLY 10+ year member]

I hope the Xmax is a typo. Thing is bottoming out big time in Bass Box software. The guy I got it from had it in a big 2.5 cube box 4" X 5" port. He was pushing it with a bridged 2ch Soundstream "LiL Wonder".

He said it sounded great before he took it out of the car he ended up selling. (The foam rotted while it sat in the back of his closet)

Just guessing that the SS amp was feeding about 150-200 watts. (Since SS never put out any numbers on the amp)

350 watts has that thing bottoming out on pretty much everything below 110Hz.

 

[Z1NONLY 10+ year member]

How much is this thing worth? (I have no idea myself)