Who has done this ?........ ( Older ALTEC Woofers )

[Cal Weldon]

Pardon my interruption but depending on the composition of the aforementioned 'goop' one might want to review the base materials and consider C4H9OCH2CH2OH aka Butyl Cellosolve.

http://www.dow.com/assets/attachment...cellosolve.pdf

Unfortunately, I couldn't find smaller than 4 litre jug of the stuff but it's not too expensive and has some interesting properties. I'm not a chemist but I play one on TV so perhaps an actual chemist can offer their suggestions here. All I know is, it did what I wanted and nothing more. The nothing more part was the one that made me post this.

[LowOhms]

Pardon my interruption but depending on the composition of the aforementioned 'goop' one might want to review the base materials and consider C4H9OCH2CH2OH aka Butyl Cellosolve.

http://www.dow.com/assets/attachment...cellosolve.pdf

Unfortunately, I couldn't find smaller than 4 litre jug of the stuff but it's not too expensive and has some interesting properties. I'm not a chemist but I play one on TV so perhaps an actual chemist can offer their suggestions here. All I know is, it did what I wanted and nothing more. The nothing more part was the one that made me post this.

Thanks for posting,

I don't think this will work. It is water based, and we need something for oil based, but then I am no chemist, and I am just GUESSING, but its a strong guess.

There must be a zillion solvents, lets concentrate on Toluene, aka Toluol aka methylbenzene. Toluene is already a chemical in the goop and we have been told by 604man, it works well as a solvent . Where can we get it in small quantities??

The whole low end and the "warmth and ambient-hall sound " region of the music plays better on my Isoproplyl treated 515B. It must be a lowered Fs and a more linear dynamic drive due to the unhampered compliance of the cone's outer surround. Pardon my attempt at tech talk, I am truly terrible at that !! You are all smart ( you OWN ALTECs ) and can figure out what I mean.

Jeff Medwin

[Audio_by_Goodwill]

Toluene is already a chemical in the goop and we have been told by 604man, it works well as a solvent . Where can we get it in small quantities??

The hardware store.

[LowOhms]

The hardware store.

Duhh..

Yes yes, ACE was the PLACE !!

Only in gallon sizes, I took one of two on the shelf. $25.99, enough for 200 ALTEC drivers !!!! $25.99, didn't hesitate.

Well, its 64 degrees this January / Sunday in Missouri, so its out on a picnic table in the sun, and re-do the 515B that has already been worked over with Isopropyl. I'm too excited to take photos as I work !!

Jeff Medwin

[Phil-G]

Only in gallon sizes, I took one of two on the shelf. $25.99, enough for 200 ALTEC drivers !!!! $25.99, didn't hesitate.Jeff Medwin

no problem, just invite some friends over and have a party.

[LowOhms]

no problem, just invite some friends over and have a party.

Well, I got the first one done, took a couple hours, and I did inhale some of it, ( did it outside with no MASK ( dummy ) and 15 MPH wind gusts.) Feel a little woozie.

Clip lead across the woofer terminals, short them out, so that the magnet structure acts a a brake to the cone, to keep it from flopping around.

Just briefly listened to the "uncleaned" versus the ex-isopropyl, now toluene-cleaned driver, A-B. The driver I worked on sounds better to me now than previously. I was thrilled. The "party" Phil-G was in my mind, with myself, and I am having a good time. Next, to acquire the A7 cabinets.

The toluene is not a easy solvent, it takes lotsa' diligent brushing, some scraping, and some careful work. But I PROMISE you all, it is worth it when the results are heard. Wear a mask, do it outside. Effects CNS, central nervous system.

This cleaned 515B driven direct, on the floor, is blowing ole Jeff away. I am so pleased, happy I did this. Been looking for good sound for a long time. This ALTEC driver is priceless to me now !!! . It takes a bit more solvent than one would think.

Additionally, I am now somewhat more confident that this 515B with surround cleaned will take me to my ultimate design goal for home HI-FI, an A7 with NO INDUCTORS whatsoever and just a cap or two and a resistive pad on the 802/811B. KISS rules.

Jeff Medwin

[Audio_by_Goodwill]

Duhh..

Yes yes, ACE was the PLACE !!

Only in gallon sizes......

That's too bad it was only in gallons. I thought for sure you would find quarts.

For other's.......I've seen toulol (or something like that) before, at the store. I'm not sure if that's another name for the same thing, or if it's a substitute.

[Cal Weldon]

I don't think this will work. It is water based, and we need something for oil based, but then I am no chemist, and I am just GUESSING, but its a strong guess.

It's actually ether based which makes it coalescent with water or petroleum products. It's basically an emulsifier. It's the only solvent I use for cleaning the 'goop' for fear of bad reactions to others.

[LowOhms]

It's actually ether based which makes coalescent with water or petroleum products. It's basically an emulsifier. It's the only solvent I use for cleaning the 'goop' for fear of bad reactions to others.

OK Cal,

Thanks for the clarification information, appreciated.

Rather than discuss which solvent to use, ( there are many listed in this thread ), I believe its far more important to be considering how many OLD ALTEC drivers are out there with sub-optimal outer surrounds. This is due to uneven or excess tar "CLUMPING " on the cloth accordion surround, hindering the driver's original compliance. Its a non linear condition.

I would like to urge "inclined" ALTEC users to DIY meticulously clean their older drivers, and enjoy a performance difference.

I spent about half an hour this afternoon, twisting the balance control on my HK 730 receiver and listening. I was comparing both 515Bs ( one stock - one with cleaned surround ) .....both driven full range and directly, no crossover.

I was using voice on Public Radio. I had initially checked these two 515Bs when I first got them last year. They played at equal volume and tone to each other.

Now, the one whose surround I toluene-cleaned yesterday is quite a bit better sounding versus my remaining stock one. ' Just twisted the receiver's balance control and A-Bed them both easily.

No comparison at all, the cleaned one puts my "stock" 515B to shame Cal. I also noticed today - the cleaned driver plays LOUDER at the same volume setting during my A-B testing. Maybe 1 dB or 1.5 dB difference...not measured, so just guessing mind you please.

I believe certain ALTEC enthusiasts could use this information advantageously.

Its hilarious to me, the cleaned surround driver SPOILED me rather quickly. YMMV, yada yada. If anyone does this, please post your results and / or please drop me a note. Have fun !!

Jeff Medwin

[VolvoHeretic]

You can usually buy lacquer thinner in pint containers which contains "Toluene (Toluol), Xylene (Xylol), Methyl Ethyl Keytone".

Lacquer Thinner

I however am leery, worried that harsh solvents might destroy the bonding agent between the cloth surround and basket and paper cone. I am also worried that the solvents might make the goop more compliant now, but as it evaporates out of the goop, it will dry it out and make it worse than before the application. Kind of like tire softener used for racing tires that dissolve the rubber and increases compliance and traction, but dries it out in the long run and leaves it hard and cracked, thus shortening the tires life span.

But then again, I also am not a chemist.