View Full Version : Altec Lansing 836a


JeepNut
07-19-2011, 10:47 PM
Hi all.
I've come to inherit my father's model 836a Lido speakers. Still have the factory tags on the back.

I know that he used to drive to Chicago from Indy back in the late 50s/early 60s just to visit the Allied Radio Electronics store up there to hear/see the latest and greatest HiFi when stereo sound was more or less "new" to the home market. I was too small to remember the trips and didn't always go with, (was only 6yrs old in 1963). But he and Grandad went up there regularly, sometimes with "the women", most times not.
But he brought these home in 1963 I believe. I'm trying to document all I can about them and have found out that they have some fairly desirable drivers in them. (and no, not for sale)

I do understand so far that these "Lido" model speakers may have come in 2 way as well as 3 way models? Can anyone confirm that?

Inspection of the interior reveals what I believe to be 755b and 402b drivers with an inductor. No tweeters in these cabinets. I just opened them up last night and the bolts and some of the unpainted metals have a white powdery residue on them, assuming a light corrosion.

One of the pair of drivers appears to be in pristine condition.
In the other cabinet, both the 755 and the 402 have been damaged but not terribly so.
The 755 has some splits in the paper cone.
The 402 the same and is separating from the ... I dunno, it obviously wasn't a rubber surround back then. I guess it's cloth with some kind of dope on it... but it is separating at the point of one of the splits in the paper. The center cone cover is slightly pushed in.
But all them seem to "move" freely in terms of the voice coil.

So I would LOVE to have them repaired. I've been told they could be fairly valuable, but not sure that remains true for the ones damaged. Would anyone know how a "repair" would affect them value wise? Only interested as a matter of documentation / insurance. I want to create a writeup for the family of these little gems.

And does anyone have recommendations for repair of these delicate antiques?

I seem to remember that there were little gold colored emblems on the fronts of them, but those appear to be missing. I seem to recall they were something roundish with the little "Altec man" in on them. Any chance of obtaining replacements?

I just refoamed a pair of Infinity Reference Ones he had also been listening to before his condition deteriorated. They hadn't seen any use in at least 5 or 6 years, but as with all things newer, not as good as the old ones. The foam turned to dust, but now that they are refoamed they sound quite nice. And it encouraged me that I should probably have these Altec's fixed.

The cabinets are Walnut and of course not plastic coated particle board, but real Walnut plywood it looks like to me. Some fairly deep gouges from careless transport and storage over the years. They've been in brothers and sister's houses over the years before coming to me finally. Only one fairly large chip out of the cabinet about 1" x 0.5" square. Otherwise I think a good cabinet maker can refinish these quite nicely. I know a few master carpenters who can help with advice on that, but for the drivers themselves I need some input.

Advice, encouragement and or any historical information is truly appreciated.
I posted a few photos here. I'll be happy to post whatever photos the group would like to see. I thought I had one or two of the exterior but sitting here now, I don't see them in my photo list. So I'll have to pull them down and get some exterior shots for the record.
Thanks so much for any help I can get resurrecting/documenting these classics. I'd love to hear Chet pick that guitar through these again, like Dad did.

eurasian
07-20-2011, 07:50 AM
You might want to have your drivers inspected/repaired by Great Plains Audio. They are ex-Altec employees and bought the original tooling from Altec when they went under--they have a great deal of experience and OE parts on hand.

The 402 in the picture can be repaired by an experienced tech--I just hope that your other 755 can be too. They are very expensive on the used market.

http://www.greatplainsaudio.com/

Sam Cogley
07-20-2011, 11:03 AM
755Bs are nowhere near as expensive as 755As, though still not cheap. They can be reconed.

BTW, the 755Bs serve as fullrange mid/tweeter drivers in this type of system, which seems to be Altec's response to the use of the 755A in the AR-1.

westend
07-20-2011, 11:39 AM
Jeepnut, could you please list your location in your profile so that anyone knowing a local capable speaker technician can lead you to him?
I've repaired cones that are similar in appearance to the ones you posted. In the case of an Altec 755, you would be better served by more expert advice and repair capability, someone that is Altec knowledgable, also. GPA is very good and might be your best resource.
Good luck with the Lido's, a project worthy on a lot of levels.

eurasian
07-20-2011, 12:27 PM
755Bs are nowhere near as expensive as 755As, though still not cheap. They can be reconed.

BTW, the 755Bs serve as fullrange mid/tweeter drivers in this type of system, which seems to be Altec's response to the use of the 755A in the AR-1.

I don't know about that, Sam. Here is a picture of a pair that sold for $1740--they were taken out of Lidos.

Sam Cogley
07-20-2011, 01:03 PM
I don't know about that, Sam. Here is a picture of a pair that sold for $1740--they were taken out of Lidos.

That's a bit surprising, but still well under the 755A price tag.


As far as repairing the drivers in this case is concerned, follow westend's advice or CALL Great Plains Audio.

JeepNut
07-20-2011, 01:38 PM
Westend said:
"Jeepnut, could you please list your location in your profile so that anyone knowing a local capable speaker technician can lead you to him?
I've repaired cones that are similar in appearance to the ones you posted. In the case of an Altec 755, you would be better served by more expert advice and repair capability, someone that is Altec knowledgable, also. GPA is very good and might be your best resource."

Sorry not so good with forums yet...
But I updated the profile now. Also emailed GPAudio w/ photos of what needs done.
I so truly appreciate the expertise and encouragement of all you folks here in working this project forward.

JeepNut
07-20-2011, 01:44 PM
...BTW, the 755Bs serve as fullrange mid/tweeter drivers in this type of system, which seems to be Altec's response to the use of the 755A in the AR-1.

Thanks Sam but wondering if you could explain a bit more on that?
I mean, I know what a 3 way vs. 2 way speaker is, but about the response to the 755A in the AR-1, I'm not clear about.

bowtie427ss
07-20-2011, 02:09 PM
the use of the 755 in the AR-1 would have been determined entirely by Henry Kloss and the folks at AR.

It didn't hurt that at the time the 755 was considered the highest quality 8 inch speaker available in production quantity.

755 was designed as a public address/paging speaker for distributed sound systems. It was designed to deliver high accuracy and intelligibility over the human vocal range. It was further designed to be compact and shallow to fit a variety of ceiling installations and surface mount baffle installations.

Western Electric didn't design the 755 to be a hifi speaker in the modern sense of the term "hifi", and Altec didn't market it as such until the very late 60's. It just so happens that the design goals, and their success in achieving them has made the 755 a coveted contender in the high end world of hifi.

Not bad for a cheap ceiling speaker eh?

JeepNut
07-20-2011, 02:16 PM
I've noticed that the 755's in these both sport the same stamped number on the gasket 600760. While the 402a's have 600930 on one and 601130 on the other.

Can anyone tell me what those numbers meant?
Thought maybe a date code, but 600760 couldn't mean 1960Jul60... lol

bowtie427ss
07-20-2011, 02:25 PM
The red surrounds indicate a time period that was probably just prior to Altec adopting RETMA which started the 391XXX series of ID/date stamping. Those numbers could be date codes, but i'm unsure how to interpret them.

FWIW, WE built and early Altec built 755A had dates clearly stamped on the gasket face.

Sam Cogley
07-20-2011, 03:58 PM
Thanks Sam but wondering if you could explain a bit more on that?
I mean, I know what a 3 way vs. 2 way speaker is, but about the response to the 755A in the AR-1, I'm not clear about.

It seems like a design inspired by (or just about copied from) the AR-1.

Tom Brennan
07-20-2011, 04:11 PM
A friend who'd been an engineer at WE sent me this response curve. He didn't think much of the 755 as a hi-fi speaker and was bemused at the value some people placed on it.

http://i254.photobucket.com/albums/hh92/Irishtom29/hi%20fi/1762.jpg

eurasian
07-20-2011, 04:31 PM
A friend who'd been an engineer at WE sent me this response curve. He didn't think much of the 755 as a hi-fi speaker and was bemused at the value some people placed on it.

http://i254.photobucket.com/albums/hh92/Irishtom29/hi%20fi/1762.jpg

I have heard several 755A rigs and have to agree with your friend. It was probably an excellent speaker by post-war standards and does what it was designed to do and has many pleasant attributes, but it sure isn't hifi and is a speaker that I couldn't live with unless tweeted, subbed, EQed, etc (I heard such a rig using AR 1s plus Janszen electrostats back in the 70's that was quite nice with about $25,000 worth of Levinson gear making it happen). I'm happy that many folks seem to like them, though.

As for price/value, I am amazed at what these bring considering that they were made in the many thousands and sold for something like $12.95 when new (granted, those were 1940's-50's $$s).

dc270
07-20-2011, 05:06 PM
If you are interested I feel confident I can repair- not recone- that one cracked paper cone you pictured.
PM me if you like.
DC

Sam Cogley
07-20-2011, 05:15 PM
Tom, I can explain your friend's problem. It was in a box. 755s like open baffles...or no baffles. Someone here has reported that the best 755 implementation they have heard was a pair of them strung up in tennis racket frames.

bowtie427ss
07-20-2011, 05:23 PM
A friend who'd been an engineer at WE sent me this response curve. He didn't think much of the 755 as a hi-fi speaker and was bemused at the value some people placed on it.

http://i254.photobucket.com/albums/hh92/Irishtom29/hi%20fi/1762.jpgIf they existed at the time, he should have included the polar response plots, they do much more to tell the story of the 755's mystique.

The flat cone profile lends itself to a nearly flat polar response out to 90 degrees across the 755's entire BW, lots of evenly distributed midrange magic there. This is also characteristic of the WE756 and WE728 members of the family.

Certainly they have no frequency extension into the extremes on either end of the spectrum. But, what they do well, they do extremely well, and have few if any peers in that capacity.

Tom Brennan
07-20-2011, 05:32 PM
Tom, I can explain your friend's problem. It was in a box. 755s like open baffles...or no baffles.

I'm somewhat skeptical of such claims Sam. Open Bafflistas often seem a rather dogmatic bunch and many seem to have never heard an open baffle they didn't like. I think Berenek's Law is prevalent among them.

In any event the best open baffles I've heard were augmented with subs save that of a fella in our horn club who used EV Wolverine 12s in OBs; they had a quite robust tonal balance.

On the other hand I don't think I've ever heard a 755 used in any manner so you are justified in being skeptical of me. ;)

JeepNut
07-20-2011, 10:08 PM
Got a reply back from someone at Great Plains Audio...
"i wish I had good news about your speakers, but the fact is I cannot repair either of the speaker any longer, I just do not with the parts."

ouch.
So it seems an alternative must be found.
DC270 I may just have to take you up on your offer to try and repair, but I'm a very handy guy. Being a Jeepnut for 20+ years requires it <wink>. And I am a Navy trained electronics tech (sonar). So the turf isn't at all unfamiliar. But considering what I'm working with here, is it idiotic to think I might repair the damaged paper myself?

I'm thinking initially about a light and carefully placed application of common Elmer's glue along the face of the ripped areas and then tacking torn halves together...
I will need to pull them down again and take the drivers back out of the cabinet to get very close inspection of the tears, but I remember one of them seemed to be a very slightly over/under separation while another seemed to be almost perfectly split apart...

They're not terribly damaged really and I personally think I could effect the repair with the right advice. Heck these were on the workbench in my garage and had them hooked up to my Denon POA-2200 / Sumo Electra playing CD's in the shop before I started doing this research and realized what I had here. Thankfully I never "exercised" the Denon...

But on the other hand I wonder why the guy from GPAudio just said "I can't help." Makes me think that maybe just MAYBE there's something more to repairing this paper than I comprehend...

How about the 402a... that separation of the paper from the suspension. What kind of glue best applied there? I have a small bottle of very sticky liquid glue supplied with the re-foam kit I bought for the Infinity Reference One's...

Or perhaps someone can think of an alternate source for a professional repair? Considering the smattering of opinion and them being exAltec guys, etc...I can hardly imagine someone should be better qualified. But if there are no "parts" in existence, maybe an "in-place repair" is the only option?
I'm really wondering why GPAudio didn't offer any kind of service at all...

I gotta tell you the Jeepnut in me really wants to take the 6 screws off the back of this 755 and see what's under the hood... but I'll resist for now... will make a few calls here around Indy tomorrow to see what kind of reaction I get from local "professional" audio repair places. Frankly I didn't see too many listed that I feel all warm and fuzzy about...

Thanks again. I'm learning a great deal here...

dnewma04
07-21-2011, 09:51 AM
If they existed at the time, he should have included the polar response plots, they do much more to tell the story of the 755's mystique.

The flat cone profile lends itself to a nearly flat polar response out to 90 degrees across the 755's entire BW, lots of evenly distributed midrange magic there. This is also characteristic of the WE756 and WE728 members of the family.

Certainly they have no frequency extension into the extremes on either end of the spectrum. But, what they do well, they do extremely well, and have few if any peers in that capacity.


I'm intrigued by this comment. A friend had a pair of these in OBs and took some measurements after reading a comment from an Altec fan similar to yours. The measurements didn't turn out so good. On axis, they were pretty nice out to 12khz or so. At 45 degrees off axis, they weren't producing anything usable past 6-7khz which is still darn good, btw. They beam like crazy, just like all large diameter full range drivers.

I sent an email off to ask him if he still has the measurements.

eurasian
07-21-2011, 10:55 AM
Got a reply back from someone at Great Plains Audio...
"i wish I had good news about your speakers, but the fact is I cannot repair either of the speaker any longer, I just do not with the parts."


I'm thinking initially about a light and carefully placed application of common Elmer's glue along the face of the ripped areas and then tacking torn halves together...
I will need to pull them down again and take the drivers back out of the cabinet to get very close inspection of the tears, but I remember one of them seemed to be a very slightly over/under separation while another seemed to be almost perfectly split apart...


But on the other hand I wonder why the guy from GPAudio just said "I can't help." Makes me think that maybe just MAYBE there's something more to repairing this paper than I comprehend...

How about the 402a... that separation of the paper from the suspension. What kind of glue best applied there? I have a small bottle of very sticky liquid glue supplied with the re-foam kit I bought for the Infinity Reference One's...


Thanks again. I'm learning a great deal here...


I'm not that surprised with the GPA response--they are more oriented towards the larger 2-way system components. I am shocked that you got such a quick reply via email, though--they have been known to ignore their email inbox for long stretches of time.

I ran into a guy who swore by the diluted Elmer's glue and tissue paper repair method for older paper cones. I guess the idea is to lay down several layers of tissue saturated with the diluted glue and to then let the whole conglomeration dry well. I think that with a big tear like your's, you would need to do this to both sides of the cone, if possible. I also assume that you should try to keep the size and thickness of the repair to a minimum.

Good luck

Sam Cogley
07-21-2011, 12:40 PM
I'm somewhat skeptical of such claims Sam. Open Bafflistas often seem a rather dogmatic bunch and many seem to have never heard an open baffle they didn't like. I think Berenek's Law is prevalent among them.

In any event the best open baffles I've heard were augmented with subs save that of a fella in our horn club who used EV Wolverine 12s in OBs; they had a quite robust tonal balance.

On the other hand I don't think I've ever heard a 755 used in any manner so you are justified in being skeptical of me. ;)

I have one...I can see why people like it, but I prefer the compression drivers. The only way I've run it is sitting by itself, no baffle at all.

I ran into a guy who swore by the diluted Elmer's glue and tissue paper repair method for older paper cones. I guess the idea is to lay down several layers of tissue saturated with the diluted glue and to then let the whole conglomeration dry well. I think that with a big tear like your's, you would need to do this to both sides of the cone, if possible. I also assume that you should try to keep the size and thickness of the repair to a minimum.

Good luck

I do that with Aileene's Tacky glue. Works wonders. I have a JBL D130 that encountered a 6-year-old's hand: two creases and a tear halfway around the outside diameter. For consistency I rebuilt the whole surround edge with a couple of layers of tissue paper on each side, and reinforced the crease/torn areas leading down from the surround the same way. It looks like hell, but sounds perfect. For a straight rip like that, I'd cut the patches to be about 1/2" wider than the damage on each side, each layer tapering inwards a bit. Two layers on each side (or two on the back, one on the front) should do it without adding too much material. One on each side might be OK, but I'd be afraid of it being too thin to maintain cone consistency.

That said, I've seen new aftermarket 755 cones on eBay. I'd try to patch that tear first, but if something went wrong a competent speaker repair person could easily fix them.

JeepNut
07-29-2011, 10:58 PM
Still debating about trying to have the 755b out of my Lido repaired.
Been watching EBay like the wife watches TV... seeing some cones for these shown with the voicecoil cap actually all-in-one with the cone. And others with the cone separated from the cap.

One seller who "seems" to be trying to be upfront, actually has offered an admittedly not-OEM-but-close-to-specs cone with the cap attached and another with the cap UNattached. He seems to have these running on Ebay pretty consistently so I know they are not NOS. He isn't trying to say so either.

Does anyone here know what is actually OEM correct?

Also curious what the consensus of opinion might be regarding the better choice to maintain the superb response of the driver.
An after-market cone replacement?
Or the tissue paper repair job?

BTW, got a second email back from Great Plains Audio. Not interested in repairing the 755 even WITH me supplying the parts. But I think I've got a couple of good local leads for recone work, however still need to have some face to face dialog to see how I feel afterward. But I AM going to attempt a repair on my own in any case. Just wanting to have a backup plan in case it doesn't go well.

Also think I need to have the speaker "dynoed" (sorry it's the only term a JeepNut can find in his lexicon that might be equivalent) to see if it meets the spec sheet shown in one of the replys above.
Would someone be kind enough to walk me through what a proper testing process might entail? Understand what the chart shows, frequency vs. response, but just what kind of bench equipment is used to pass the frequencies through the driver? And how do they measure the response? is it done simply with a mic in front of the driver into some sort of monitoring/recording device?

Thanks