846B Restoration

[Marvin]

I have a pair of Altec 846B's I purchased new in 1976. One of the horns has been repaired. Other than that, they have never been altered. I have always loved the sound, but lately they just don't seem to sound the same. Is there an upgrade program, refurbish, or am I stuck with what I have. Other than the foam part of the grills falling apart, they are perfect. I don't want to sell or trade them, I just want the sound improved to much as it was.
Thanks

[Marvin]

With so many audio pros on this forum, why can't I get a response to my posting?

How about a recommendation as to a company that will refurbishes my Altec 846B's. They are 35 years old and need to be restored to their original sound quality. Any suggestions?
Thanks,
Marvin

[hjames]

With so many audio pros on this forum, why can't I get a response to my posting?

How about a recommendation as to a company that will refurbishes my Altec 846B's. They are 35 years old and need to be restored to their original sound quality. Any suggestions?
Thanks,
Marvin

I am not an Altec owner, but I have heard them mention Great Plains Audio as the folks who picked up the legacy Altec technology. I gather the owner doesn't do emails, but if you search this site for Great Plains you should be able to find a phone number so you can discuss it with them.

[BMWCCA]

http://www.greatplainsaudio.com/contact.html

[Earl K]

Marvin,

They are 35 years old and need to be restored to their original sound quality. Any suggestions?

- The problem for all Altec owners is that no one can actually achieve a proper ( bona fide ) restoration in the strictest sense of the word .
- The original parts no longer exist .
- The best you can hope for is a facsimile &/or perhaps even an upgrade ( whatever that may mean ).

- One problem here is that the Altec Corp you gave your money to, is gone / & there are just pretenders to the throne .
- As mentioned already, the best ( & only ) maker of ( essentially real ) Altec parts is Bill H. at GPA ( who bought a goodly portion of Altecs' original parts tooling, when Altec closed its' doors ).

- The 8 ohm diaphragm ( # 21597 ) for your 806-8A driver hasn't been made for about thirty years . It's been replaced by GPAs' # 34647 diaphragm ( which, by my reckoning is a slightly heavier & more high powered version ).
- You can see for yourself what the proper part numbers were ( back in 1975 ) for your speaker by clicking on the picture I've included .


- I've heard that a pair of GPA replacement diaphragms will cost @ $ 200.00 uninstalled ( installed would be more since it means 2-way shipping of your drivers to Oklahoma ) .
- A better option ( IMO ) is to buy a pair of these drivers from GPA ;
- ( I think they will physically fit depth-wise / but you need to check this out for yourself since a pair is around $ 400.00 I believe ).



- You could consider this driver an upgrade since it has more extended HF response than the original 806 ( which takes a dive in response after 10K ). It would be worth your while to remove one horn driver to identify if it is in fact an 806 / perhaps your 846b is newer / with a different driver .


- Compounding any real "restoration process" is the fact that capacitors like the type found in your crossover can eventually change their values and also change their sonics ( as they age ) .
- The original caps ( of which I have opened up a couple ) had a dielectric material that was made from a lightly waxed, craft paper ( layered between aluminum foil ) .
-This type of cap ( dry paper ) has a unique sound to it / & / it's an open ended question as to whether or not they should be replaced / & if so, replaced by what type of cap ?
- Replacing this type of cap ( with a modern successor ) is virtually impossible / since "dry paper" caps haven't been made & sold in decades ( they have been functionally replaced by plastic film type caps using 'Mylar" or "Polypropylene as the dielectric .
- There are "wet paper caps" ( called PIO ) that many audiophiles love / along with ( of course ) audiophile prices . Google, "PIO caps" or "PIO Capacitor" to begin your education on the matter .
- These market changes leave the "restorer" with a significant dilemma / because once one decides to replace the caps then one has to find a cap type whose sonics suit the system . There are just as many opnions on what is a suitable replacement as there are grains of sand on the beach .
- You'll need to lurk about and read as much as you can on this forum & others as to what some of those opinions are ( learning to use the search functions of various forums is therefore a must if you want to plumb the archived opinions of those who have gone before you . )
- FWIW, IMO, "wet MPP" motor-run caps are about the closest approximation to the older dry paper types ( that I've auditioned ) . MPP stands for "Metallized Polypropylene" . Motor-Run caps are found in AC circuits for large motors / such as HVAC systems . Ebay offers surplus motor-run caps on a pretty regular basis ( though never of the correct value to be of much use to the "plug & play" type .

- It's always worth a look around at Jeff Markwarts' website to check out his recommendations on various topics . If you contact him, perhaps he'll rebuild your crossovers or ( most likely ) build you new updated types. He makes some recommendatons for manufacturers of the different parts found in a passive crossover .

>< cheers

[Marvin]

Thanks so much guys. I am very ignorant as to what I need to do to get my (846B) Altecs to perform as close original as I can. I really appreciate your input as to my dilemma. I have read some of the postings here and I must admit a lot of it is WAY over my head. I just remember listening to music from the 70's, closing my eyes, and I could just see the artists performing in my living room. I want to get that sensation back.

I know there is a speaker restoration company in Tampa Florida I have emailed that says they can refurbish my (846B) Altecs. They are call "The Speaker Exchange". I would hope anyone having dealings with this company would give me their opinion. I don't want to give my drivers and crossovers to just anyone. Like I said, I have had these speakers for 35 years. The cabinets are perfect. It's just the sound that is the problem.

Again, thanks for your comments. I am listening and I will take you advice seriously.
Marvin

[Earl K]

Hi Marvin,

- I don't know "The Speaker Exchange" and haven't heard any mention of them ( that I can remember ) on the various forums ( good or bad ) .
- OTOH, if they ( Kathy I guess ) are promptly responding to emails that's better than you can expect from GPA ( who respond best to telephone calls /as goes the scuttle-butt ).
- I'd stay away from buying one of their premade crossover solutions for your 846B(s) . Stick with simple recapping .

- I'm still inclined to suggest that you hand over your drivers to GPA ( since they are the sole manufacturer for all the present-day replacement parts for Altec drivers ).
- GPA will also tell you whether or not it's true / if the 34647 diaphragm is actually available ( since they're the ones who can make it. I mention this because the web-page for the Speaker Exchange states the 34647 replacement diaphragm is NLA .
- Additionally, GPA will also recharge the magnet of your 806 drivers (remagnetize) when they install the new diaphragms ( as well as install the necessary diaphragm connector adapter kit that's needed because your older diaphragms have a different style of connector ).
- Take some pictures of the inside parts of your N800K crossovers . If the capacitors are accessible ( seen, after removing the Xover from the cabinet ) then I would recommend replacing the caps yourself ( or having someone local to you do this / like a local TV repair shop ) .
- It is really a simplistic matter for any person owning a soldering iron . You'd just need to source some replacement caps first / so they are on hand if / when you take it to a repair person .

- On a different matter, why are you blaming your speakers for the change in their sound ? ( It might be another component in your playback system has not aged gracefully / such as a preamp or amplifier ). What led you to this conclusion ?

>< cheers

[Marvin]

Earl,
I know one of the horns was blown and repaired (by me). Also the sticky substance on the accordion portion of one of the woofers has puddled at the bottom. I also believe after all this time the caps in the crossovers need replacing.

I have replaced the amps many times. The Altecs always sounded good. They still sound good, jest not as good as I remembered them. Also, one of the pots on the back has a dead spot.

I would like to pull all the components out and send them to a qualified technician for a thorough check out. Something I can't do, but feel needs to be done. I jest don't know who or where to send them. Your suggestions and comments are appreciated. I know I can count on the guys on the forum...
Thanks,
Mavin

[Earl K]

I have replaced the amps many times. The Altecs always sounded good. They still sound good, jest not as good as I remembered them. Also, one of the pots on the back has a dead spot.

- Okay, just checking that you've got the right culprit .

I would like to pull all the components out and send them to a qualified technician for a thorough check out. Something I can't do, but feel needs to be done. I jest don't know who or where to send them. Your suggestions and comments are appreciated. I know I can count on the guys on the forum...

- I suggest only entrusting GPA to do a full diagnostic of the 6 components // if you're dead-set on pulling & shipping all the parts .

- I would do this only after you've found a bullet-proof shipper ( & taught yourself bullet-proof packing / think ; "drop-tested" from 4 ft onto concrete as an adequate protection-test ) .

- Frankly, six shipped components / shipped both ways / can only end in tears & frustration ( I fear ) .

- Holding out till you find someone qualified for the diagnostic work / that's also within a drivable distance / is the only sane approach to avoid calamity ( IMHO ) .

sorry for the dark clouds ><

[Marvin]

No apology necessary Earl,
This is the kind of advice I was looking for. I will pursue this situation with much caution.
Thanks

[Marvin]

Sheese, If you read what GPA disscribes about packaging, I might as well carry my speakers to them personally. Ha, only kidding. My speakers are like gold so I can appreciate where they are coming from. You can't be TOO careful.

I have read on the forum where some members are substituting components to try to improve the performance of their speakers. I wonder if this is wise?

To try to improve means to change the sound quality. Is changing the sound really a wise choice? If you change the crossover, the HF driver, or the LF driver what are you accomplishing? I for one would like to know. Is the average person MORE knowledgeable about the quality of audio reproduction than the engineers at Altec?

I would think if the exact components were not available for these speakers, than components that closely resemble there performance would be the preferable replacement. What am I missing here? I don't want someone to tell me that "IN THEIR OPINION" this component or that component is "BETTER" than the original without some facts to back it up. In my humble opinion, the original is still the best. Like original vinyl recordings, tube amplifiers, and Altec speakers. Please enlighten me. With all the modern technology, sometimes the old stuff is still the best.

I'm not trying to put you down, just trying to understand your thinking.
Thanks for your contribution,
Marvin

[sonofagun]

Speaker Exchange will do a fine job on the drivers.

I make 846B replacement foam grilles.

[Marvin]

I talked to GPA who is the authorized Altec repair facility and they informed me thay can do all the necessary work on the drivers. HOWEVER, they do not rework or repair the crossovers. They suggested I consult the knowledgeable people on the forum for advice as to the best components to refurbish my original crossovers.

So, HELP! As a former Dinosaur computer tech, I feel comfortable in replacing the various components. I just would like advice on what to replace and where to obtain the said components. Is there a kit maybe, or a list of parts needed. GPA also said the components made today are superior the the original ones. I think I remember seeing a schematic somewhere in the forum. Although not necessary, I'm sure it would be helpful also.
Thanks for all the help,
Marvin

[Earl K]

They suggested I consult the knowledgeable people on the forum for advice as to the best components to refurbish my original crossovers.

So, HELP! As a former Dinosaur computer tech, I feel comfortable in replacing the various components. I just would like advice on what to replace and where to obtain the said components. Is there a kit maybe, or a list of parts needed. GPA also said the components made today are superior the the original ones. I think I remember seeing a schematic somewhere in the forum. Although not necessary, I'm sure it would be helpful also.
Thanks for all the help,

- Wait until you get back your refurbished drivers ( from GPA I assume ) before doing any crossover mods . Give the system a listen for a couple of weeks before deciding your next step .

- This way ( taking a step by step approach ) you'll be able to track what mods lead to what sonic changes & whether or not you actually like them .

- Don't be naive and just assume that "better or more modern" ( according to GPA ) means you'll like it .

- Parts Express will be a valuable source of parts for your crossover rebuild .

>< cheers

[Zilch]

There's two caps in it. Let's pretend it's some kinda big deal: