12" Bass Driver Wanted - For Goodmans Goodwood Speaker

Welcome to the forum!

A picture is always nice:

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There's currently a replacement on buy it now at auction, marked Type: C/112/1012/8:

https://www.ebay.co.uk/itm/353921734010?hash=item526761157a:g:zOYAAOSwpSJiEK2h&amdata=enc:AQAIAAAA4CW3e3RSYgWVo1U0nScEN4UBhaiL+vKQsDuVjHpRp/BbRpU/fQ9NgyfoJcb1f/JBZThaBpzwO2ZpmJyTNoKwJm+JXyBFmFfi9y5ArvO5rfvGwO0mv35spe0ZDCd0lZGSfEL/wqtuxGIfr3v9wVx9yd3RaN6JrqfkW3R7xQ7Sjl9iV6skq0nwjdX66NQNL7vJhLQ3mmiT2ihEPawFs6zs7E3bprlLkJO9qLubPVaNL5QHwQJg61IFtBabrD5c7NIhCNX4vPSeuv5d0dMkzqsIcLI4U/YiWdi7xmQdp1dDykb7|tkp:Bk9SR-aBuan-Yg

It looks pukka from a 100% seller who shows an ohmmeter confirming voice coil continuity.
 
Smudge, I hope you have determined that the bass driver itself is definitely faulty and that the problem does not lie elsewhere, as in the wiring or in the crossover.

Since this is your first post and I don't know how familiar you are with speaker renovation, I'll mention that a simple way of checking is to swap the bass driver with the one in the other speaker to see if the fault follows.
 
There are 3 ways to proceed: 1 buy another speaker
2 Remove the working woofer, measure it on an infinite (large) baffle with a $100 omnidirectional microphone and software such as ARTA or REW. Then buy a driver with similar size Vas Qt Fb impedance and watts rating.
3 Buy a driver for impedance and size and try it. You have no apparent ports, so you want a woofer of same size, 4 ohms impedance, watts rating and Qt > 0.4 . You can assume the woofer takes about 2/3 of the watts rating of the entire speaker. If watts rating is not on the back label, you may be able to look it up on the internet.
I did #3 to a KLH98 and the results weren't too bad. Bass was light due to low sensitivity I bought, but the church elder complained the previous speakers I donated, Peavey 1210, had too much bass. He wanted an organ that sounded the same as the 1957 Wurlitzer, but without the motorboating sounds.
Happy shopping and repairing.
 
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There are 3 ways to proceed: 1 buy another speaker
2 Remove the working woofer, measure it on an infinite (large) baffle with a $100 omnidirectional microphone and software such as ARTA or REW. Then buy a driver with similar size Vas Qt Fb impedance and watts rating.
3 Buy a driver for impedance and size and try it. You have no apparent ports, so you want a woofer of same size, 4 ohms impedance, watts rating and Qt > 0.4 . You can assume the woofer takes about 2/3 of the watts rating of the entire speaker. If watts rating is not on the back label, you may be able to look it up on the internet.
I did #3 to a KLH98 and the results weren't too bad. Bass was light due to low sensitivity I bought, but the church elder complained the previous speakers I donated, Peavey 1210, had too much bass. He wanted an organ that sounded the same as the 1957 Wurlitzer, but without the motorboating sounds.
Happy shopping and repairing.
Thank you for that.
Option 1 sounds perfect, but there aren't many of these Speakers around. They are, after all, over 50 years old.
Options 2 onwards - you may as well be speaking another language - with my inexperience 🙁
 
I can't do # 2. I don't buy things made in ***** so I don't have an omni mike. I've piddled with REW but just at the surface. Buying a driver of right size, impedance, I've done that. The "tech" at the musician's resale shop doesn't do any better. He repaired a 1210 speaker I bought with an 8 ohm driver instead of a 16, making the speaker a 6 ohm instead of an 8 ohm. I blew a pair of amp transistors that way.
If you have a DVM, impedance (8 ohms, 4 ohms) is 4/3 the resistance you measure. The coil inductance adds the other 1/4th.
 
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