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JRD
01-12-2008, 06:35 PM
I was just given a pair of Altec Fifteens by a friend of mine, and I'm trying to get them looking and sounding their best. Unfortunately they are lacking grilles, and one of the knobs as well as the knob faces are missing from the MF/HF controls, and the veneer on the edges is shot. But I have a number of questions, both in regards to appearance and electronics.

First off, I know that finding replacement grilles for them will be practically impossible, so I will likely build my own frames and just cover them in cloth. I know that the originals were foam but I've already concluded that it won't be cost effective for me to try to recreate the originals. But I have a question regarding bases - it appears that the speakers once had recessed strips of MDF, probably 1" high, that they sat upon, and which no longer exist. Were they glued on? And in lieu of them, would a isolation cone system installed on the bottom be a better system or would it color the sound negatively? Or would 1" rubber feet be a better solution? I have yet to decide if I will use them on the hardwood floors of my living room or in my garage on concrete.

Next, regarding the crossovers - although the components are mostly in spec, I am replacing the resistors and capacitors with new ones, and also I am going to remove the smaller inductor and flip it sideways to prevent EM distortion effects. It seems odd to me that they were mounted so closely and in the same orientation - was crossover design in those days unaware of the effects of inductor mounting isolation? Also, I am planning on using Jantzen capacitors, any pros or cons in this regard? I'm assuming they will be superior to the originals, which are bulging and one is even showing signs of leaking. Also, I will be replacing the original wire hookups with binding posts that I can use banana plugs with, I don't think anything larger than 18 Ga. wire will fit in those original push button terminals. Also, both dust caps have been pushed in, so I am replacing them. The surrounds are in good shape though, and the diaphragms on the compression drivers were apparently replaced by OC Speaker in the not too distant past.

Next is a matter of dating them. I have perused the catalogs on the forum and it appears that they are about 1978 vintage. I loved the fact that the 1978 catalog photos were taken in Dana Point Harbor, someplace I am quite familiar with, in fact, my friend who gave them to me grew up in Dana Point and I in San Clemente. But the photos in the catalog show the ports on the Fifteens to be mounted below the woofers to the right, while on these they are mounted between the horn lens and the woofer on the left and the crossover controls opposite them on the right. Would that indicate a later model, perhaps a series II or something?

Also, even though I'm not planning on selling them, what would their value be? The drivers appear to be the original 802-G's, and having been serviced they appear to be fine. Cosmetically there are some scratches but I will likely sand and re-oil the boxes. The grilles will cover the edges so I won't need to re-veneer them, although I want to keep them from being too thick so I will have to design them to fit as flush as possible. I may try to recreate the original bases if that is recommended. I'm assuming they had a slot in the rear for the wires to exit. Plus if anyone knows where I might get a replacement knob or knob faces LMK. Sorry this post is so long, and TIA for any info regarding them, I appreciate it.

Earl K
01-13-2008, 06:01 AM
Hi JRD

(i) Re; the missing base ( skirts )

- Here's one solution to your query ( add wheels & restore the wood skirts ) .

(ii) Value ?

- Typically, intact as a speaker, much less than a $1000.00, & it seems only if someone lives nearby who's willing to pick them up ( to forgoe the high shipping charges ) .

- And not nearly as much as a current eBay seller thinks he'll get . His sale is referenced in this thread here. (http://www.hostboard.com/cgi-bin/ultimatebb.cgi/ubb/get_topic/f/3729/t/3351) ( The lads at the Altec forum are having quite a yuk over this sale . )

- Parting out the speakers will likely not bring much more than $ 600.00 ./ and even there you're going to need to prove that the replacement OC diaphragms are actually Altecs ( & not some aftermarket type that OC also sells ) .


(iii) Replacement Knobs ?

- LHF member GaryL has a bushel of these for sale ( original Altec crossover knobs ) .

(iv) Replacement Foam ?

- LHF has 2 suppliers of aftermarket Foam fronts . They have been concentrating on the JBL market / but they might make you a custom foam replacement for your Model 15s.
- "sonofagun" and "indycraft" are their LHF monikers .

(v) Inductor Orientation ?

- Certainly what you say is true when the coil types being used are air-cores . I've measured the interference in aircores when they get too close and/or are not oriented properly to each other.

- Iron-Core inductors likely have more immunity ( due to their smaller sized coils per Henry ) / though I don't have any loose ones here to measure this conjecture .

- Do model 15's use Iron or Air-cores ? ( Here's an eBay pic that doesn't tell me much ) Here's a Model 19 Xover pic ( N1201-8a ) showing its arrangement of iron cores ( "E"-type, I believe ) .

(vi) Capacitors ?

- Can you show us a picture of these bulges ?
- FWIW, typically Altec used PIO ( paper in oil ) caps back then. They were a black plastic cap with "bulging red acrylic plastic" ends.
- Jantzen PP film caps will be "different" than the existing caps in there . You should notice a cleaner horn sound .

(vii ) Dating of the product ?

- I have no clue if there was a series II style .

Earl K
01-13-2008, 07:48 AM
(vii ) Dating of the product ?

- I have no clue if there was a series II style .

" Live & Learn " :)

- Here's a pic of the Model 15 Series II

http://audioheritage.csdco.com/vbulletin/attachment.php?attachmentid=16087&stc=1&d=1150077254

- & here's an excellent analysis of the M-15 crossover, as modelled by Richard C ;

:)

JRD
01-13-2008, 11:00 AM
Earl-

Thanks for the photos, I discovered the series 2 brochure after browsing a bit more extensively after my post. So, seeing as they are series 2, and the series 1 came out around 1975, would you say they are circa 1978 or so?

As for inductors, they are air core, so I think I've got the right idea in realigning the smaller one. I was trying to write up a crossover schematic similar to the one posted, but in looking at it, there are three inductors and they have different values than the ones in my crossover. Are you sure that is an M15 schematic? I measured them at 1.2 mH and .58 mH (although in the photo I have the 1.2 marked as 1.25), so in looking at the schematic posted I can't figure out why there are three inductors shown.

On the capacitors, the 8 ohm one has the bulging ends as you mentioned, but the 3 ohm one is leaking. I figured the Jantzen caps would likely help with clarity. It seems every manufacturer goes cheap on their crossover components. When I was working for Sound Image and hand-building all the crossovers for their 1250 series monitors, they used all Solen caps, and while the Solens aren't the best in the world, they are better than any I've seen in any OEM crossovers for non-commercial applications. Even the Infinity Kappa 8's I rebuilt for my cousin had cheap crossover components and they were the nicest speakers I have yet to encounter in my limited experience with higher end home speakers.

Anyway, I'm enclosing a photo of the inductor realigned, plus I got further into the compression driver on one when I noticed a rattling - turns out that they are the original Altec diaphragms, and that the wire has broken on one, as in the foreground of the x-over pic. I'm doing this on a serious budget right now, so my inclination is to go with the aftermarket diaphragm to replace it. Is it worth the $40 extra to go with the OEM Altec one and is it going to lower the value so significantly that it makes it not a good idea or is it going to color the sound that much differently? Since the OEM ones are available, if I were to sell them the new owner could always get them if they desired, I figure.

Yeah, I saw that joker on ePay with his $2000 M15's, and was laughing myself. But that's par for the course when it comes to ePay, I see that all the time with pinball machines, which is my other hobby, people thinking their stuff is worth outlandish values because "I saw one just like it on eBay for $XXXX so mine is worth all that and more." But speakers, like pinball machines, are worth what their condition merits, and one guy's perfectly mint one is NOT going to be what your thrashed incomplete and poorly restored one is worth, thank you very much. But my question was not so much based upon resale value, since like I said I likely won't sell these, just for my own edification.

You really think wheels and skirts are the way to go for these? I can see the skirts, but wheels I can't see. Sure, they will decouple the speaker from the floor, but I don't want them moving around. I'll probably keep them in my garage, since that is my music room and workshop. I figure they will fill the 2000 sq. ft. with sound no problem, and since it's a mix of concrete and carpet and lots of stuff they shouldn't be too bad sounding. Typically of me, rather than plugging them in when I got them to test them out, I just tore them apart first and discovered their issues, so I have yet to hear just what they will sound like. My buddy assured me that the highs on them were phenomenal, but obviously the one with the broken wire isn't going to be much until I replace the diaphragm. I may plug the other one in for kicks and test it, but first I have to put pins on the ends of the 10 ga wire that I use, otherwise I won't be able to plug them in! Thanks for your replies, I am going to hit GaryL up for a knob. Any idea what he asks for them?

John

Earl K
01-13-2008, 11:32 AM
Hi John,


As for inductors, they are air core, so I think I've got the right idea in realigning the smaller one. I was trying to write up a crossover schematic similar to the one posted, but in looking at it, there are three inductors and they have different values than the ones in my crossover. Are you sure that is an M15 schematic? I measured them at 1.2 mH and .58 mH (although in the photo I have the 1.2 marked as 1.25), so in looking at the schematic posted I can't figure out why there are three inductors shown.

- There aren't 3 ( or 4 ) inductors shown in the M15 schematic
- Richards' schematic ( the one I posted above ) only shows 2 actual inductors . The other two ( apparent ) coils are really just a representative of the inductances of the horn driver & woofer / along with their relative impedances. That info is necessary for an accurate simulation ( & therefore it's entered into the SIM program Richard uses ).

- Thanks for the "air-core" affirmation . Yes, the original configuration is close enough for some "mutual inductance" between the two coils . I too would try moving one .


would you say they are circa 1978 or so?

- That's close enough . FWIW; the Model 14 superceeded this model sometime in the early 80s .


It seems every manufacturer goes cheap on their crossover components.

- FWIW, most of the original capacitors ( Altec ) from this period are "paper in oil" . They aren't bad sounding at all / though at this point in time they're likely drying out and therefore replacement with a reasonable cost PolyPropylene film cap, is a "step up" .
- Once you've done a replacement / how about cracking one open to see what's inside ? ( & then post a pic )


I'm doing this on a serious budget right now, so my inclination is to go with the aftermarket diaphragm to replace it. Is it worth the $40 extra to go with the OEM Altec one and is it going to lower the value so significantly that it makes it not a good idea or is it going to color the sound that much differently? Since the OEM ones are available, if I were to sell them the new owner could always get them if they desired, I figure.

- Yes ( from what I see on eBay ), "aftermarket" diaphragms will significantly lower the resale value of labelled or non-lablelled 802-8Gs .
- OEMs from GPA cost in the $100.00 range ( if my memory is correct ) .
- IMO, buying "aftermarket" diaphragms will only hasten your decision to eBay this pair .



You really think wheels and skirts are the way to go for these?

Sure,,, if they need to be mobile somewhat / especially in a busy garage .


I am going to hit GaryL up for a knob. Any idea what he asks for them?


- Look Here ! (http://audioheritage.csdco.com/vbulletin/showpost.php?p=119100&postcount=1)

:)

Gary L
01-13-2008, 12:10 PM
Here is what the 15s should look like if you bring them back to close to original.

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15done.jpg

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15grill3.jpg

Original grills were foam and have long since disintegrated and I have never yet seen one of our foam makers offer the 15 replacments.

It is no easy task to get them to accept cloth like I did but worth every minute of your time to do it right.

Knobs, sure, I have the exact one you need! Actually I have close to a thousand of them. Just another of my hair brained ideas that I will be burried with.
I have to credit Earls tenacity to bring up old threads that we thought were lost in space or time.

The only time I have ever seen these knobs for sale was on XOs and you had to buy the entire XO just to get the knob. I found the company that made them for Altec and had to buy 1000 and pay the set up fee to get them to make em. In the two years since I have had them I think I sold 16. LOL
I know because my wife reminds me daily!:D

15s are a very fine speaker and worthy of bringing them back if not too molested. The bottom skirt was screwed in place and I see no benefit in wheels.

Gary

Earl K
01-13-2008, 12:20 PM
It is no easy task to get them to accept cloth like I did but worth every minute of your time to do it right.

LOVELY !

- Great job there Gary. I prefer it to the original look ( seen only in pics , mind you )

- That wooden divider strip is very classy .


Knobs, sure, I have the exact one you need! Actually I have close to a thousand of them. Just another of my hair brained ideas that I will be burried with.

- I think I was dimly aware of that quantity. ( Maybe you & Zilch should team up to offer grill cloth with knobs / I think he's overstocked on the dark blue stuff )

:)

Gary L
01-13-2008, 01:14 PM
Thank you Earl!

I would bet we would all feel like kids in a toy store if we ever got to see each others "Treasure Troves".

More and more I ask myself why the heck I need all this stuff! I suppose it is good to have a lifetime supply of some stuff but somehow knobs and blue cloth was never really a part of the plan;)

Gary

JRD
01-13-2008, 06:09 PM
Thanks Gary and Earl, I appreciate all the help! Gary, what would 3 of the knobs cost me sent to 92590? Do you accept Paypal? Now you can tell your wife you are up to 19 of them sold!! That should make her ecstatic! One of mine is still perfect, amazingly enough. I love the tangerine hang tag, I don't suppose you have more of them. A question about the tangerine - what made me take apart the rattling driver was apparently the tangerine floating around loose in there and rattling against the diaphragm - but when I removed the three screws, they were all tight. Now, the VC former seems to be glued in place properly, how would enough room open up in there for the tangerine to rattle?

OK, for the skirts I found the four holes that were used to mount them. No wonder they probably fell off, one screw per side isn't cutting it. Actually part of the reason they were given to me was they got a little wet and that no doubt led to the disintegration of them. I have a nice sheet of 3/4" birch ply that I could cut strips off of and recreate them, do you think it's too dense? Should I cut the strips with 45 degree angles and glue them up, then glue them and screw them to the cabinets? Is that how the originals are? I'm not planning on moving them around much, like I said my garage is my music room. It isn't so much a garage as a workshop and game room, although it does have two rollups and my car and truck both fit as well. It totals 2400 sq. ft., 30' x 80', and the stereo is against one wall with about 18' between the speakers. Here's a photo just for reference. I love that this forum allows attachments, so many others don't. Unfortunately, however, I can't tell from your photo of the speaker with the grille where the dividing strip is and what it looks like, it's just too dark. Also, did you recone those speakers? My cones are faded to a much lighter color and the surrounds are also not nearly as nice looking. I saw that someone is selling some OEM Altec recone kits for the 414-8's, that is what these are, right? I don't want to go to that extreme unless I need to, in fact, I'm going to try not replacing the surrounds if possible since they are still good. This is just a fun project for me and the less I spend, the better, since I don't have the cash right now to be throwing into these. Things are a little rough right now in my line of work and this is the last thing I need to be spending money on. I was hoping to get away with $20 on the caps and dust caps and now with the $75-100 for the diaphragm it's already spiraling out of control. Not to mention the knobs....

Anyway, I'll try to do it a little at a time here and work on making the cabinets look good, since I've already got all I need to work on them. As for the rest of them that'll get done as money permits, not a high priority right now. Here's a photo of them as well. Like I said edge veneer is shot but I'll either try replacing it or just covering it with the grilles. Thanks again.

John

Gary L
01-13-2008, 06:35 PM
Looks like you have some work ahead.

More tomorrow as I am heading to bed but here is what the original grille frames look like. They have a black aluminum frame with a pressed board insert that had the foam glued to it, probably about 1-1.5" thick. Note the notch on each side just below the horn cutout. The original foam had a thin metal strip where mine now have wood and it separated the top from bottom and simulated the 14 & 19 look.

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15grill2.jpg

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15grill1.jpg

Please drop me a PM with your address if you want knobs, Earls post where he linked my initial offer has the info. The knobs are exact OEM and will match the one you have.

More on your HF drivers and woofers later but they are NOT 414-8s.

Here is what they are;

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15front.jpg

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15cone.jpg

http://img.photobucket.com/albums/v722/Gamalot/Speakers/15back.jpg

Gary

JRD
01-14-2008, 11:12 AM
Gary-

PM is on the way after this. I can see why you redid the surrounds on yours, obviously they were shot. I don't know if mine just weren't used as much, or if the mild SoCal climate has just been less damaging to my surrounds, either way the foam has a limited life and mine will probably need redoing sometime in the near future, likely after I put them through their paces and the existing foam gives up the ghost, so to speak. Every other speaker I have encountered that is near this age has needed new surrounds, it's possible that they were already redone at some point, and that would certainly be the reason for the OCS repair stickers on them. Maybe I should call them and have them run the numbers that are on the stickers and ask them what service what performed on them. I could always drive up there, Garbage Grove is about an hour drive from me. But since then the dust caps were pushed in by a zealous toddler and that is why I have cut them out and am replacing them. But as I said before, mine are much lighter in color, but only on the portion not covered by the dust cap, probably they were in a location where the sun was able to hit them and lightened them up. Which, if that were the case, the surrounds would be in far worse condition so that would also point to a previous replcement job.

So what model are the woofs, just in case I were to order a recone kit? Like I said, I have yet to listen to the speakers, perhaps the VC's are shot, I don't know yet. And any idea about the loose tangerine as I questioned in my previous post? I am also including a shot of the other crossover, which I have also realigned the inductor on but have yet to replace the components. (The caps and dust caps are ordered but they won't be here until the end of the week.) Thanks.

John

Gary L
01-14-2008, 01:32 PM
Yours appear to be a similar vintage to mine. Don't know the woofer number but GPA can recone/refoam if necessary. I got the foam from Parts Express and did it myself, they sent both a large roll and small roll with the kit and the large was the one. The kit also included the new dust caps.

I replaced my L pads in each and used Dayton Caps.

My cabinets were pristine in every way which is why I bought them, just needed the grills covered.

The 802-8Gs were sent to GPA and got the magnets recharged and new diaphragms installed. The tangerines were both loose so they re glued them, all for $90 each back two years ago.

There is a slight gap between the dome of the fram and the top of the phase plug. If the plug comes loose you will hear a rattle and it will destroy the diaphragm or at the least dimple it.
Your frams appear to be the original 23744s and if not burnt out or damaged then keep them. If you need new then buy 34647s from GPA and just send the drivers and have them done right with the remagging all included.

Some here like the 23744s and refer to them as LIGHT. I can't hear a difference but the new 34647s are a great deal sturdier in the way the lead wires are routed. I just know when Bill at GPA rebuilds them they always come back quick and ready to sing for another 30 years!

I don't know or have a way of testing magnetism and just always figure if the leads to the frams are burnt then they could probably use a recharge to be safe and sure.

The original bases were just particle board covered with some dimpled black vinyl and screwed dead center on each leg. Mine are original but the original owner had them up on shelves and off the floor from day one.

For the grilles I made a press board insert just a hair shorter then the original and with identicle cutouts. I covered it with cloth and affixed it to the original one inside the aluminum frame. I also made a walnut strip to mimick the original look of seperating the top and bottom.

15s are an excellent speaker particularly in the HF and Mid F ranges. A bit short on deep bass and they work great with a sub or second set of bassier speakers played together.

If you bring them back to close to what mine look and sound like I would place a value between $600-$800 depending on time of year and who is looking. You might even do better parting them out as I have seen some pay rediculous prices for the 802-8Gs.

If I had room for all my altecs I would certainly keep my 15s but they just don't get any play time when there are much larger 19s & Clones to choose from.

Another nice sleeper in that line are the 9849-8Ds on top here. They have the 414-8C woofers and metal rather than plastic horns.

http://img.photobucket.com/albums/v722/Gamalot/Speakers/DSCN1414.jpg

Gary

sonofagun
01-15-2008, 03:44 AM
I made replacement foam grilles for Altec for several years and have made numerous for the 15s for which I have the specs. Price is $150/pair + shipping and you can order either with or w/o the horizontal groove for the original metal band. See my web site www.foamspeakergrilles.com (http://www.foamspeakergrilles.com) for more info. You'll need to make a mounting frames or I can make frameless grilles for an extra $50.

Those cabinets look pretty rough! You might consider just starting over and make new ones - could be several advantages.

JRD
02-20-2008, 07:55 PM
I just wanted to say thanks to everyone who replied to my queries and helped me out on this project. I have yet to replace the one bad diaphragm, but I just finished rebuilding the crossovers and reassembling and testing one of them, and I have to say I am impressed by the speakers - good crispy highs and decent bottom end for a relatively small enclosure with only a 12" woofer. And many thanks to Gary for throwing in that 4th knob - that was a nice gesture. It's good to find a forum with folks who are really into their hobby and willing to help out others without the BS that I see on far too many other forums, things like inflated egos and heads and constant bickering and infighting.
Anyway, I got all new L-pads after discovering mine were shot, got audio grade resistors and went with a mix of Dayton and Jantzen caps, partly because I wanted a superior quality cap and partly because those were the only ones that matched the original values. Then I replaced the cheesy spring terminals with 5-way binding posts. Also I reconfigured the inductors so they wouldn't cancel each other out, and then I put on those nice new knobs I got from Gary. I'll likely pass on getting grilles, the industrial look will work fine in the garage. I will get around to staining the new skirts to match the cabs and finish my refinishing job soon - It's kinda low priority right now, especially since I'm doing the same damn thing for work right now on a new staircase, and god knows the last thing you want to do after spending the whole day doing it is the same thing but not for pay. I can live with imperfect cosmetics for now, since they're just going in the garage, not the living room. But so far my total investment in them is about $75, and after the new diaphragm for that same additional amount, I should have a nice set of vintage speakers for $150 that will be worth significantly more than that, and more importantly, sound quite good. I can't wait to hear them both with a good quality record, it will likely make me glad I spent extra to get that nice Garrott Bros. cartridge on my digital turntable and the correct old Shibata stylus for my antique AT14SA cartridge on my other table. Since these things were made when vinyl was king, I think it's safe to assume that vinyl will have the proper sizzle to get the most from them. They seem to be real power monsters - what are others using to drive them? I'm going to use my Ramsa WP-9220 PA amp so I think I shouldn't have any problem giving them all the power they'll need, but I sure wish I still had that old Sansui receiver I had back in high school, it would probably be perfect for them.

Gary L
02-20-2008, 08:26 PM
One thing you will quickly learn about speakers, they don't need to look good to sound good!

I had some real rats in the past and before I got in to woodworking. Even covered a few pairs with contact type wood grain to cover all the sins but as long as they sound great, thats all that mattered back then.

Lots of vintage Altecs came in either a road worth grey box or a home version in walnut or oak veneer. Didn't matter at all to the way they sounded.

These days when I find Altecs in the shape of yours I usually just make new cabinets for the components to go in as I find the effort to refurbish is just about as hard.

One thing for sure though, for a garage system you sure do have a nice set of speaks!

I run mine with a Sansui G 8000 of just about the same vintage and they are a sweet receiver/speaker combo.

Gary

Tranquil
12-02-2008, 08:25 PM
Thanks for a great thread guys. The mod 15's look great. I like the bent horns they have a mellow sound, I have them in my 9849 monitors I find them very easy to listen to over long periods.I have been setting up my 604's and needed knobs for the crossovers, I was able to purchase them NEW from Gary at a great price. These are impossible to find unless you find crossovers being sold for parts.Thanks Again

Tranqui

Gary L
12-03-2008, 05:40 AM
Thanks for the plug Tranquil.

As for your horns in the 9849s. My 9849-8Ds had metal while my buddy has a pair of 9849s in grey cabinets with the plastic or model 15 type horn.

Hard as I try I can't tell much difference between metal Vs plastic. If any then there may be a slight ring with the metals at times.

I have been completely thrilled with the service and performance of all my GPA diaphragms, HF driver and woofer rebuilds. Any HF drivers I purchased with after market frams took a trip to GPA to get the right ones and tuned up. I find no good reason to use after market parts or services while the real stuff is still redily available and at a reasonable price.

Gary

Tranquil
12-03-2008, 09:10 AM
My cabs are the 9849-8A. The components were purchased separate the 414-8c is original and it's a great sounding speaker, the horns are plastic with 902-8A drivers, phrams from GPA and they sound great, NO ringing like my 811 but I know how to tame the 811 just have not done it yet. I'm also very happy to have Bill at GPA in business.
I bought the utility cabs in bad shape and refinished them, the distributor for Duratex textured paints is here in Fl. so I took a cab in and had them match the paint project turned out nice. They kept the formula on file for future Altec customers. Great stuff easy to work, dries quick with NO smell.

Tranquil