1967 Executive 972 opinions? Updates on restoration.
- Thread starter grindfix
- Start date
OOOOP's. 
I got to crossover recap today. So far, one side all drivers ohm test good. I pulled one
woofer out to check surround condition. It’s very thin see- through fabric. Looks like treated with some kind of polymer but definitely not sealed. I know cabinets are not airtight sealed air suspension type but was wondering if sealing or at least treating those surrounds would be beneficial. Has anyone tried to do that? Opinions?
woofer out to check surround condition. It’s very thin see- through fabric. Looks like treated with some kind of polymer but definitely not sealed. I know cabinets are not airtight sealed air suspension type but was wondering if sealing or at least treating those surrounds would be beneficial. Has anyone tried to do that? Opinions?
little-al
Active Member
Like many things there are quite a few debates on whether to re-seal fabric surrounds, and how.
But if you believe it would be worthwhile, vintage-ar on eBay is the source most often cited as having the correct "ACOUSTIC RESEARCH CLOTH SURROUND WOOFERS LARGE SEALANT KIT, ALSO KLH"
But if you believe it would be worthwhile, vintage-ar on eBay is the source most often cited as having the correct "ACOUSTIC RESEARCH CLOTH SURROUND WOOFERS LARGE SEALANT KIT, ALSO KLH"
I just don’t know what that will do in the console setup. In air suspension type it will tighten up the loose bass as diaphragm will be moving against cabinet pressure resistance. Sealing surrounds in this cabinet design may not yield same results. Just don’t know. Most console woofers I’ve seen had folded paper or fabric surrounds and were not as soft as these are.
Looks like the Butyl rubber disintegrated on the cloth.
Most of the FISHER Speakers in consoles from 1962-63 on (10" and up) had a Butyl rubber covered cloth suspension. It was very tacky when applied and even up to 5 years ago in my Executive. I would seal them with the suggested coating to stiffen the surround. If the cabinet is open, it won't hurt it, nor will it help with SQ. Acoustic Susp. will definately improve SQ.
Most of the FISHER Speakers in consoles from 1962-63 on (10" and up) had a Butyl rubber covered cloth suspension. It was very tacky when applied and even up to 5 years ago in my Executive. I would seal them with the suggested coating to stiffen the surround. If the cabinet is open, it won't hurt it, nor will it help with SQ. Acoustic Susp. will definately improve SQ.
Definitely doesn’t look like anything has disintegrated. Looks like surrounds were made this way. So do spider and center cap. See - through. Here is the picture of how it looks from the back against light source.
Here is what the dial looks like in the dark.
I managed to seal off all light bleeding on the back and front of the glass and added a coat of green lacquer to the edge of the glass. Madisound sells 1/2 x 1/8 foam gasket strip priced by foot. Much better then cutting Armaflex tape.
Here is what the dial looks like in the dark.
I managed to seal off all light bleeding on the back and front of the glass and added a coat of green lacquer to the edge of the glass. Madisound sells 1/2 x 1/8 foam gasket strip priced by foot. Much better then cutting Armaflex tape.
Those look like ones in my console.
How did it change the sound? Or did it? If it does not - why do it?
On the other hand, I have about 10lb of 1/4” Butyl tape and I can seal around all drivers and cabinet corners to turn them into air suspension. Lots of work but this amp is probably very low damping factor and may not sound good with speakers of that kind.
I’ll finish other side crossover tomorrow and will have a listen to it as is. Crossovers are stapled to the side of the cabinets with multiple staples and removal without the damage to 3/16” thin board is nearly impossible. My knees and back only allowed to do one side today working inside of the cabinet. Hoping that other side drivers are all good.
How did it change the sound? Or did it? If it does not - why do it?
On the other hand, I have about 10lb of 1/4” Butyl tape and I can seal around all drivers and cabinet corners to turn them into air suspension. Lots of work but this amp is probably very low damping factor and may not sound good with speakers of that kind.
I’ll finish other side crossover tomorrow and will have a listen to it as is. Crossovers are stapled to the side of the cabinets with multiple staples and removal without the damage to 3/16” thin board is nearly impossible. My knees and back only allowed to do one side today working inside of the cabinet. Hoping that other side drivers are all good.
That's where a couple of College football players nicknamed Bubba and Mongo, along with a couple of saw horses come in handy. Or a large foam mat.
fred soop
Super Member
The woofers were sometimes bottoming out at low frequencies. That was cured. Otherwise, no audible change in the overall sound.
Be careful sealing an open enclosure to try and convert it to acoustic suspension. The woofers may not be designed for that. An AS woofer has very little restoring force to center the woofer as it is depending on the trapped air for that. A vented woofer will have a stiffer suspension.
I listened to it and let it run for about 3 hrs. I don't know if capacitors really need some time to break-in and form but initial impression is not very satisfying. This receiver sounds much better (amazing actually) with separate speakers connected to main speaker jacks compared to ones that are in the console. Woofers do bottom out on heavier bass notes.
Crossover caps were replaced as follows: 2uf, 12uf, 18uf electrolytics were replaced with Dayton Audio films and 100uf with 100uf PE brand non-polar electrolytic, bypassed with 1uf Dayton audio film.
So it sounds like I should stiffen those surrounds but spiders concern me. They are non treated fabric. Will the VC stay straight working against stiffer surrounds?
Also, next time woofers come out, that itchy fiberglass gets thrown away and cabs vacuumed. I will probably staple pink insulation to cover everything except woofer itself and thinking about experimenting with adding a vent tube. Anyone tried to do that?
Crossover caps were replaced as follows: 2uf, 12uf, 18uf electrolytics were replaced with Dayton Audio films and 100uf with 100uf PE brand non-polar electrolytic, bypassed with 1uf Dayton audio film.
So it sounds like I should stiffen those surrounds but spiders concern me. They are non treated fabric. Will the VC stay straight working against stiffer surrounds?
Also, next time woofers come out, that itchy fiberglass gets thrown away and cabs vacuumed. I will probably staple pink insulation to cover everything except woofer itself and thinking about experimenting with adding a vent tube. Anyone tried to do that?
Think it' was a Butyl base. The surrounds on my '65 Futura were sticky as of 5 years ago. I imagine they still are. I used thinned Aileens Tacky Glue on a pair of KLH 20's and it sealed them up and sounded pretty decent. I compared them with my other pair that have solid surrounds and coulldn't hear any difference.
The spyder's should be ok.
The spyder's should be ok.
Larry,
Check my discovery in this thread. Let me know what you think, will you?
https://audiokarma.org/forums/index.php?threads/looking-for-suggestions-to-improve-sound-of-fisher-console-speakers.930748/#post-14146878
Check my discovery in this thread. Let me know what you think, will you?
https://audiokarma.org/forums/index.php?threads/looking-for-suggestions-to-improve-sound-of-fisher-console-speakers.930748/#post-14146878
Do what you suggest in the thread with a small spot. If after 24 hours it hasn't dissolved the surround and the supporting structure, a few thin coats will probably do. I would do the blanket on the flipped over driver for a week or two just to get the weight of the cone and coil centered back in the magnet. Then coat it, and let it cure a week or so with the blanket on it. (Cornstarch on the surround, just enough to "DE-Stick" is fine).
