Well I had a bit of a result today... you know the sort of thing: chatting with someone you've just met in a social situation and when you mention that "my son plays a bit of bass quitar" you're told they used to play bass and they have an old bass cabinet in their garage you're welcome to if you're willing to pick it up.
It's almost always unusable junk, right? Just something else to be carted away on the next trip to the dump...
Well not this time! This time, whilst the cabinet was very battered and at the end of its life, the main speaker looked pretty decent and the badge said "JBL Professional Series Model 2901". I did not recognise the tweeter but it looked like a serious piece of iron too... Could I have lucked out? Maybe so... I got out of there quick before they could have second thoughts!
The cabinet is pretty much beyond help, but the K-140 looked OK until I gently pushed on the cone to see if it made any nasty noises and discovered it wouldn't budge much... on removing the speaker it was obvious why: someone had shoved a series of foam strips between the basket and the cone (see attached). I was surprised that the K-140 did not have a serial number.
The high frequency diver turned out to be a 2461 driver with a 2301 horn and lens. This looked OK also althought the horn has come a little loose - I assume I can just tighten that up. The 2461 is marked as 16 ohm (the K-140 is 8 ohms) though I have not checked that with a meter.
The whole lot was wired up with a 3101 passive crossover.
The cabinet is around 3.5 cu ft (21" x 27.5" x 10.5") with two ports 4" ID and 2" long. No cleats but several edge-attached chipboard battens to stop flexing.
The owner claimed it was quite a box in its day, which I can well believe as they are clearly good components.
I have not powered anything up yet.
I would be very interested in any comments on the appropriateness of these drivers for the role of a Bass guitar cabinet. Any pointers to suitable cabinet designs would be great as I'd like to build a new cabinet to give these drivers a second life. I have not been able to find info on the 3101 yet. Does the impedance of the 2461 make sense with this crossover?
What I would most welcome is some insight into why the K-140 was treated in such a brutal manner! I'd also love to know what is the best way for me to proceed - is it safe to just remove the foam and power the whole lot up? Does this treatment mean that a recone is inevitable?
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