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Altec Model 9 - Refoaming

corpblues

corpblues

AK Member
Picked up a pair of Altec Model 9's. I don't think they are series II, as I don't see series II anywhere on the speaker.

I would appreciate any information anyone has on these speakers. Specifically if there a different between series II and series I.

These are very heavy cabinets, shipping must have been much cheaper back in the 70's.

And would greatly appreciate any tips on refoaming them. I have successfully refoamed 3 pairs of speakers in the past but I read a few comments that the model 9 mid's are tricky to refoam but can be done.

The woofer and mid needs to be refoamed. I pulled the woofer to ensure I buy the right kit. I do not see any manufacture stamped on the woofer. The back side of the cone has 18-03-02-3919 (not sure on the first 2 digits) and the frame has 20 QO 75 6 23.

Here are a few pictures to hopefully help identify the driver and proper kit.

IMAG1332_zpsru37f3kz.jpg


IMAG1340_zpshnpuihua.jpg


IMAG1337_zpsbhgbrtme.jpg


IMAG1339_zpskprdxam8.jpg
 
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I pulled the other woofer to see if there were any different marking on it. Basically the same as the other, see below. Put one on the scale and it weighted 10 lbs. Both have 3 screws on the back but no manufacturer labels. The serial number on this speaker cabinet is 01900.

They appear to have never been removed from the cabinet until I pulled them out.

Can some with Altec experience confirm if these are original Altec woofers?

IMAG1359_zpsrqk0n0dn.jpg


IMAG1363_zpskjbvygf2.jpg



IMAG1361_zpsqloeymnz.jpg
 
If this post in the link below is accurate, they appears to be authentic early altec model 9 woofers.

Still looking for any information on these model 9 series 1.

Does anyone have any tips for refoaming the mid's and finding new gaskets?

http://www.hostboard.com/forums/f700/179237-need-help-identifying-model-15-model-9-woofers.html


"I think those are early birds, part #23891. Early model 9's and early 15's used a stamped steel frame 12 inch woofer. Those look correct. My 15's have the later cast basket 33785's. AFAIK, the 23891 and 33785 use the same motor and moving parts, only the frames differ."
 
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After a long night of scraping and gluing, They Are alive!

I removed the dust caps and used spacers for the woofer re-foam. The tolerance in the voice coil seemed pretty tight, so I did not want to attempt doing it by hand as I usually do. This my first time replacing dust gaps and using spacers and it turned out to be an easy job.

I still plan on re-foaming the mid-range speakers but I was anxious this morning to see if how they sounded. Will probably tackle the mid-ranges this weekend.

They sound pretty darn good even before the mid-range re-foam. Currently I have them connected to a Luxman R-404 which I picked up for a couple of bucks. Will try them out with my McIntosh after they are 100% finished.

Currently listening to Rush - Moving Pictures on LP and it was well worth the effort!

The gaskets were pretty much toast, so will have to order some new one as I don't like seeing the shiny metal. They also had a 1/2 inch thick cork spacer glued over the paper gaskets, I assume to prevent the grill from ever touching the woofer. Not sure if I'll put those spacers back on as it looks nicer without the big ugly black cork spacer, plus it took me hours to scrape off all the old spacer glue.

Before
IMAG1354_zpsv87uatsq.jpg


After
IMAG1409_zpss4t1ramx.jpg


What in the heck?
IMAG1416_zpshvgjluuh.jpg

And I have no idea what these are. One was laying inside each cabinet when I opened it up. Seem to server no purpose other than rattle around. I could not find any obvious place they fit.
 
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Bob Orme said:
Those white caps used to be glued to the back of the midrange magnets.
Click to expand...

Bob, thanks you are right. I pulled the midrange speakers to refoam them tonight and on the back of the magnet there is a mark where they were glued on.

Question now is, should I glue them back on?

I assume I should as that appears to be the original design.

IMAG1427_zpsr6mdem2b.jpg


IMAG1426_zps2tyocfhn.jpg
 
Yes, you should glue them back onto the mids. They prevent woofer back pressure from affecting the mids through the pole piece vents, and they keep dust out of the voice coil gaps.
 
Bob Orme said:
Yes, you should glue them back onto the mids. They prevent woofer back pressure from affecting the mids through the pole piece vents, and they keep dust out of the voice coil gaps.
Click to expand...

Thanks Bob, AK proves it value yet again. I refoamed and glued the poly caps back on the midranges last night. Listening to them this morning and they sound even better now. The mids are now much more clear. The mids sounded a bit muddled before, not sure if that was from the deteriorated foams and/or the missing poly caps. They are a marked improvement with both repaired.

Thank you for the guidance. :thmbsp:

IMAG1429_zpspqvlwvsn.jpg
 
Back in service as they should be.

Sounds like I'm sitting in a late night Jazz club.

Currently being driven by a McIntosh MAC 1700 with a Technics SL-1200MK2-A turntable. Smooth.....

IMAG1431_zps0jdf7s1c.jpg


Not sure if the grill covering is original or not. It is very 70's looking.
Most of the pictures I can find of these speakers have grills removed.

IMAG1433_zps7439wp5k.jpg
 
I adjusted the settings on the speakers themselves, treble up and mid down, and these are sounding very nice. I had adjusted both controls high trying achieve more high end, but after the I turned the mid's down, the highs now ring out better.

Just a little volume on the Altec Model 9's and they get crazy loud.

I am hoping to obtain a pair of JBL L-100's to a/b compare the Model 9's. I'm now thinking the Altec model 9's might hold their own. The popularity of the L-100's have driven the L-100 prices high, so I'm waiting and hoping to stumble upon a pair that someone is not overly proud.
 
I am about to sell these tomorrow.

I REALLY hate to part with them, but decided to go with my JBL 4311's. The altec's are too large and loud for my needs. The altec model 9's are great rock speakers, as they are very efficient and get loud very fast. I currently have them connected to a 32 watt Luxman R-404 Receiver and it becomes too loud about 1/3 volume. I threw on a Jimi Hendrix CD and wow they sound great.

Shoot me a quick PM if you are interested in them before they are gone.
 
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I've decided to not sell these for now.

Connected them this evening to my McIntosh MAC 1700 with a B&O CD-X player. Listened to a few CD's and A/B compared with my JBL 4311B's and I still really like the model 9's.

I did have the model 9's connected for a while to a small luxman receiver and the CD-X player which sounded fine, but connected to the MAC 1700 & the CD-X CD player they reach a much higher level of performance.
 
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Very nice corpblues. I bought a brand new pair of 9's when I worked at Altec back in '78-'82. Great speakers. I think you made the right decision to keep them.
 
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