Altec a7

[hatrack71]

Hi, I am a new member to this forum but have been an audiophile for over twenty years. I just got a pair of A7 cabinets and would like to know which set of horns and drivers, crossovers, and woofer models are going to provide the smoothest sound and transparency. I am looking at 416's, 811's or 511's, but I don't know which crossovers or drivers to go with. Also, is the 416 my best choice? Can someone explain the different designations after the drivers( A,B,C, ect.)? Thanks, Kyle. Oh, my listening room is 20ft.x15ft.x8ft. high.

[Russellc]

Hi, I am a new member to this forum but have been an audiophile for over twenty years. I just got a pair of A7 cabinets and would like to know which set of horns and drivers, crossovers, and woofer models are going to provide the smoothest sound and transparency. I am looking at 416's, 811's or 511's, but I don't know which crossovers or drivers to go with. Also, is the 416 my best choice? Can someone explain the different designations after the drivers( A,B,C, ect.)? Thanks, Kyle. Oh, my listening room is 20ft.x15ft.x8ft. high.
Which a7 boxes do you have? Are they like the ones in my avatar? Are they plywood or mdf?The early ones dont work with the later 16 inch drivers. If yours do PM me about a set of 515 8G, which were designed specifically for this horn loaded application.

As to the 416, you will typically find 416 A, 416 B 416 8c. the a and B models are older and rarer and have alnico magnets. the later 416 8C, like the 515 8G, use ferrite mags that dont need rechargeing like alnico can. Most of these are also available in 8 and 16 ohm versions.

Either the 811B or the 511B will work, the 811 being designed for 800 Hz and higher cross over, and the 511B works down to 500 Hz.

Typical drivers that will work with both of these horns are the 800 and 900 series compression drivers. Most commonly used are 802 D, 802 8g, 808A, 808B in the 800 series and 902 8A , 902 8B, 902 8T, 908 8B in the 900 series. there are others, most of these are very similar in most regards, with differences for the application they were intended for.

Hunt around on the altec site for more info as well.

Russellc

[hatrack71]

Hi Russell, yes they do look like those in your avatar. I really appreciate your response that was very helpful. Currently I'm running Klipschorns with Cary sla-70 and Audio electronic supply pre-amp. A friend told me the altecs were a superior set-up, so I bought cabinets from him. I hope I can find components at a reasonable price. Thanks, Kyle.

[Russellc]

Hi Russell, yes they do look like those in your avatar. I really appreciate your response that was very helpful. Currently I'm running Klipschorns with Cary sla-70 and Audio electronic supply pre-amp. A friend told me the altecs were a superior set-up, so I bought cabinets from him. I hope I can find components at a reasonable price. Thanks, Kyle.

Well, it sounds like you are on your way. Some of the drivers are better suited to home use and high fidelity. Those that are less desireable many times can be "converted" to the better version.

If you havent seen them yet, take a look at greatplaines audio site. They are basically some of altecs last people, and were able to obtain most of the altec manufacturing apparatus and they crank out brand new drivers identical to the originals. They aren't giving them away, but they are no more expensive than good condition collectable vintage Altec either.

There is a lot of info and links on that site, and as I remember, one is to a nifty little chart that compares and contrasts all the old Altec cone drivers and compression drivers, both large and small format.

This journey usually consists of buying everything you can get your hands on to try, then you keep what you like, and sell the rest. Doubtful you will ever loose a cent on any of it.

I would save time and get either the Altec 416 8C and 902 8A, (or the 802 8G) or Great Plaines versions. (Call Bill there, dont bother emailing, or email Todd over at the Altec forum if you are interested in his new versions.)

For a crossover, go to parts express and order their 800 Hz crossover, and enough dayton poly prop caps to repopulate the board with, perhaps some theta .01 caps for bypass on the high frequency crossover caps. Compensate the high end with the altec "T filter". This will remove some shout and extend the high frequencies at the cost of a little distortion.

I am sure many will have many other good ideas, but I tell you this collection of stuff works well.

As an aside, what are the backs of your cabs like? Does the entire back panel remove, or just part of it? When the back panel is removed and you look in the back of the cabinet, is it sealed off around the driver, or can you "see" into the backs of the flares?

Russellc

[allen mueller]

I went through this not to long ago with my altec boxes, and decided to go with the 416 from GPA based on the good advice from other memembers and could not be happier.


http://audioheritage.org/vbulletin/showthread.php?t=17984&highlight=woofer

[doodlebug]

I'd suggest you consider the GPA/new driver approach. Doing the math, if you pick up used drivers, odds are they'll need reconing and magnet recharging anyway. Bill at GPA can run down the costs of reconing vs new for you. This will tell you what you'll have to be able to buy used drivers for to break even vs GPA new. Hint: Call Bill - don't email.

I had my 604s reconed there and would quickly do it again if they needed it. Heck, he even supplied me with a replacement UREI blue horn for one, too!

We are fortnuate to have someone like Bill and GPA around so we can have exchanges just like this thread.

Cheers,

David

[Zilch]

Currently I'm running Klipschorns with Cary sla-70 and Audio electronic supply pre-amp. A friend told me the altecs were a superior set-up, so I bought cabinets from him. I hope I can find components at a reasonable price.
http://audioheritage.org/vbulletin/showthread.php?p=10471#post10471

Quote from another forum:

Originally Posted by Tom Danley

"Last summer I rebuilt a pair of Altec A-7’s for a friend, I replaced the Altec Driver with a BMS 4550 and not only was it more sensitive, had flatter response but it went out an entire octave higher "flat".

I used a JBL 2226 for the low range (normally I shun expensive drivers except he had them and it seemed appropriate to have at least something "Lansing" in it) and re-tuned the box and the end product had a 2+ octave wider bandwidth than the original with several hundreds of degrees less phase shift through crossover, to boot.

I took pictures and intend eventually to do a DIY article because when they were done the they sounded wonderful...."

[Russellc]

http://audioheritage.org/vbulletin/showthread.php?p=10471#post10471

Quote from another forum:

Originally Posted by Tom Danley

"Last summer I rebuilt a pair of Altec A-7’s for a friend, I replaced the Altec Driver with a BMS 4550 and not only was it more sensitive, had flatter response but it went out an entire octave higher "flat".

I used a JBL 2226 for the low range (normally I shun expensive drivers except he had them and it seemed appropriate to have at least something "Lansing" in it) and re-tuned the box and the end product had a 2+ octave wider bandwidth than the original with several hundreds of degrees less phase shift through crossover, to boot.

I took pictures and intend eventually to do a DIY article because when they were done the they sounded wonderful...."
He must have started with an older A7 box, when I held a 2225H or 2226H up to the mounting hole, there wasnt enough speaker to fill it!

Russellc

[Zilch]

He must have started with an older A7 box, when I held a 2225H or 2226H up to the mounting hole, there wasnt enough speaker to fill it!He never did the article, that I'm aware of, but Tom Brennan posted the details of Danley's A-7 conversion from a private communication in one forum or another.

My point is that a cookbook Altec load is not the only option here, and perhaps, not the best one, even, for "Audiophile" performance.

If anybody's actually interested in doing it, the information is available.... :yes:

[Mr. Widget]

Originally Posted by Tom Danley

I used a JBL 2226 for the low range (normally I shun expensive drivers except he had them...


"I shun expensive drivers" give me a break. I shun bad expensive drivers, fine, but limiting yourself to only using "bargains" is the same trap that Paul Klipsch fell into. What a stupid statement.


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[Zilch]

WIDGET.... The first thing to do with the Klipschorn is to throw out the drivers and horn...


Those do tend to be the most common mods. I finally had a few free minutes and set up the K-horns in my living room... I rather like the mids and top. Sure I could nit pick at them all day long, but it's the lack of deep bass and the murky lower mids that trouble me the most.

I also have a pair of time aligned mini monitors sitting in front of the mighty K-horns... absolutely no bass, but a coherency and image that the mighty Ks will never know.

All that said, I can understand the folks over on the Klipsch forum who are quite pleased with their rather ancient speakers.:DSo, Mr. Widget, having recently auditioned a pair of K-horns in your living room, and being well familiar with A-7s, would you consider A-7s to be the worthy upward migration in audiophile performance over K-horns for home use under discussion here?

[Mr. Widget]

So, Mr. Widget, having recently auditioned a pair of K-horns in your living room, and being well familiar with A-7s, would you consider A-7s to be the worthy upward migration in audiophile performance over K-horns for home use under discussion here?I'd say it's pretty much a draw, but in general I'd favor the K-horn over the A-7.

I'd make the choice depending on your room and personal preference. I think they are both potentially enjoyable but not what I'd consider SOTA these days.

FWIW: I am still listening to these K-horns simply stock, warts and all and find them quite enjoyable on some music and a bit resonant and annoying on other music.


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