Driver replacement, just the FAQ's mam (ahem, men:-)

[influx]

Ok I've done the prerequisite searches on the forum and have bits and pieces of the info I need but I'm far from a complete picture . I'm replacing the mid drivers in a vintage speaker (Scott S-11D's) for which there is little to no data on. One driver is shredded but the other unit works fine.

FAQ #1: to recone or not to recone? What are the pros and cons of this option.

FAQ#2: Determining the frequencies and plots of the vintage box and its drivers (T/S?). Without a spec sheet what do I have to do to figure out the properties of the mid driver (remember I still have one good one)? My goal would be to match as closely as possible the good driver or spec and mess with XO's as little as possible:-(

I'm committed to preserving the sound of these vintage gems. They have a nice intimate pull-you-into-the-music character. Parted out replacement drivers for these 40 yr old speakers are few and far between; I've been looking for awhile.

I realize I have to figure out what the frequency range the damaged mid was operating in lst. I assume I have to fiqure out the frequencies for the tweeter and 12inch woofer as well; in short I gotta figure out what the XO is doing!

FAQ #3: What else? I'm in there so I might as well recap and rewire right? The existing wire is thin and cheesy and the caps probably dried up 20 years ago! What cap type? what value? and is rewiring beneficial? The woofers have rubberized cloth surrounds and look like they'll go another 40yrs. The tweeters are sealed (ferro fluid) and very nice so the rest of drivers are set for now.

I can dropin a speaker, I can recap and I rewire but were do I begin in matching and choosing the right replacement mid drivers?

Hope to hear from someone soon!

Geoff

[influx]

........and I mean Raw. See photos attached

[Jezz-the-Fezz]

Hi Influx,

Hope I can be of some help. Did a little ferretting on Google, but couldn't find out much about your speakers/drivers. Do they have any writing on the drivers themselves indicating things like impedance/power rating? What about the crossover - could you draw a circuit diagram with component ratings? Worst case scenario, you'll have to deduce the speaker parameters from the crossover & replace both drivers; preferably with contemporary units that match tonally. Replacing just the one driver will knock the stereo picture completely out of whack & mess up your imagery.
Don't despair - there are quite a few vendors specialising in vintage audio drivers; you might wind up with quite a novel period upgrade!

[influx]

Hi Jezz,
thanks for the prompt response. Here's what else I know about these:
6-8ohm impedance
60w nominal
blown driver is a chambered paper mid/woof in a sealed box.

Scott was a fairly conservative company. I've done a fair amount of googling myself researching these and several models share the same components from year to year. I'm sure I'll find what I need.

Depending on the cost it might make $ense to see about reconing first. (I don't want to dip too deep into the speaker kitty- still have dreams of building my 1st MTM's :-) So I'm checking this out first.

Either way the XO's will need a little attention; though they are doing an excellent job right now.

Here's a photo of the driver.

[planet10]

The tweeter is a Philips AD0160 (likely /T8)

What are the numbers on the mids? You will not find a recone, you'll need to find something real similar (i'll have a look in my stash -- those plastic cups look quite familiar). What does the mid look like under the plastic enclosure?

dave

[influx]

Originally posted by planet10
The tweeter is a Philips AD0160 (likely /T8)

What are the numbers on the mids? You will not find a recone, you'll need to find something real similar (i'll have a look in my stash -- those plastic cups look quite familiar). What does the mid look like under the plastic enclosure?

dave

I'm impressed- you made the call on the tweeters! Numbers on the mids are 022-1130-038
27744
2857426

I can't get the cups off the mid without cracking it- it's glued on tight.

Thanks for your response!

[planet10]

Originally posted by influx
2857426

Made by Rola end of June 1974. Likely a ceramic magnet

I can't get the cups off the mid without cracking it- it's glued on tight.

The quite similar CTS i found are the same ... glued tight.

dave

[influx]

The CTS's in fact show up on several later Scott models. A nice looking pair came up for auction last week. Thought about bidding on them but didn't know enough about them at the time.

[KBK]

You know, there is a scott speaker I saw a while back..that had a cabinet damping trick (and brutally smart, at that) that has thankfully been lost in the annals of time. So it can be discovered again! by someone else, and they can be applauded for it's 'novelty' and 'genius'.

We did it a while back, thinking we were smart. Then we discover..taking apart an old Scott speaker...(from about '59 or so!!!) showed us ..well!..we wain't so smart after all....

[planet10]

Originally posted by KBK
a scott speaker I saw a while back..that had a cabinet damping trick (and brutally smart,

Details? (please don't leave us hanging)

dave