Suggestions for an Altec build

[gamalot]

I have collected some nice Altec components over the many years and need another project. I am a cabinetmaker but nor real knowledgeable with box plots or electronics.

Here is what I have on hand to work with that I would like to use.

2- 414-8C woofers
2-802-8G horn drivers
2-811B horns OR 2 of the plastic bent horns from the model 15 speakers.
I also have crossover networks from both the model 15 and model 19 speakers.

The end game is a set of rears to match my Model 19s I use in the front. Compact boxes will be a plus because I don't have all that much space for very large rear speakers. At one point some year back I think I had a pair of 9849s that we loved but just too large for the space I have to place them in.

I'm not sure you can stuff big sound into small boxes but I do know some of you guys can guide me on how small I can go with the parts I have. Building cabinets is easy if I have the plans to work from.

Thank you

Gary

 

[BillWojo]

Sounds like you have some nice hardware to get started. May I suggest that you modify your post title to include Altec, that will get a few of the smarter Altec guys involved.

BillWojo

 

[gamalot]

Sounds like you have some nice hardware to get started. May I suggest that you modify your post title to include Altec, that will get a few of the smarter Altec guys involved.

BillWojo

Suggestion noted Bill and well accepted but I can't seem to get to where I can edit the title to add Altec

 

[BillWojo]

I think you may have to be a subscriber to do that, not 100% sure. You could always ask a moderator to help you out. Just click on the report button.

BillWojo

 

[elitopus]

I use my 414-16b's in around 1.75cuft cabs. They have decent bass down to 50-60hz.

With your's being rear speakers, I wouldn't think they would have to be bass monsters anyways.

Your cabs will probably have more volume than mine just to fit the horns (I use some 12" wide Dayton horns).

 

[gamalot]

I use my 414-16b's in around 1.75cuft cabs. They have decent bass down to 50-60hz.

With your's being rear speakers, I wouldn't think they would have to be bass monsters anyways.

Your cabs will probably have more volume than mine just to fit the horns (I use some 12" wide Dayton horns).

Thanks E, I have no problem using the plastic bent horns from the model 15s that fit the drivers perfectly. They are a little over 16 inches total on the outer edges.

Keeping these boxes as small as I can get is where I want to go with them and I did like the HF from the bent horns which allowed for much shallower cabinets.

 

[BillWojo]

I have a set of the bent horns I picked up to play with after reading about them. Seems a lot of Altec folks hold them in high regard as to there sound quality.
I see you fixed your thread title.

BillWojo

 

[bowtie427ss]

You can shrink the box as much as you like, it's just going to raise the LF roll off point proportionately, and will require some sim'ing of the box to get the porting right for the box volume you end up with, and to be sure the woofer wont un-load and become a victim of over excursion when the system is pushed hard. The latter would be my biggest concern since we're talking about speakers that will be used as rears driven in parallel with large, sensitive mains(my assumption).

 

[mhardy6647]

The -- ahem -- "bent horns" to which some have referred really are worthy. Really worthy.

If you have some free time burning a hole in your pocket (not to mix metaphors or anything), you could do worse than invest it in perusing this thread from AA, I'd opine.

http://db.audioasylum.com/mhtml/m.html?forum=hug&n=176642&highlight=Emilar+joe+roberts&search_url=/default.mpl?searchtext=Emilar&b=AND&topic=&topics_only=N&author=joe+roberts&date1=&date2=&slowmessage=&ip=&sort=score&sortOrder=DESC&sortRank=Forum&forum=hug

https://www.audioasylum.com/messages/hug/143220/altec-32a-and-32b-horns

http://jelabs.blogspot.com/2016/02/altec-32b-horn-redux.html

It's all about that throat...

 

[bowtie427ss]

It's all about that throat...

Asymmetrical, and not Altec's only venture with non-symmetric horn designs.

I ain't no expert in horn theory. But, i'd opine that asymmetry in the horn path elongates the acoustic center which eliminates the on-axis peaks(or at least some of them) which are characteristic of so many other vintage horns.

FWIW, 32B's are my daily drivers currently.

 

[gamalot]

I have a set of the bent horns I picked up to play with after reading about them. Seems a lot of Altec folks hold them in high regard as to there sound quality.
I see you fixed your thread title.

BillWojo

I followed your lead and the mod did it for me. I was not aware there were/are differences between the plastic 32B and the Metal 32A horns until I read some of the above posted info. My 2 pairs are the 32B plastic ones and both sets came with 802-8G drivers needing diaphragms. I really do want to match these up with the 414-8C woofers I have and make as compact a box as I can get away with. I just can't blow out the walls of my living room to fit something like a 9849 which I already had and sold for that reason. I do miss an old pal Zilch who provided me with some great plans when I was reworking the size of my Model 19 cabinets because the 30 inch wide 19s just could not fit. Now they have a place in my room being 24 inches wide but deeper.

 

[bowtie427ss]

I just can't blow out the walls of my living room to fit something like a 9849 which I already had and sold for that reason.

They're working just fine on either side of my desk, elevated such that the sweet spot is at seated ear height, in the near field. They're sort of like a big set of headphones.

But you're right, for smaller Altecs they're a pretty big speaker.

 

[gamalot]

They're working just fine on either side of my desk, elevated such that the sweet spot is at seated ear height, in the near field. They're sort of like a big set of headphones.

But you're right, for smaller Altecs they're a pretty big speaker.

I have bought and sold so many Altecs over the years and can't remember all of them. Didn't you get your 9849s from me?

 

[EarlK]

Gary,

I would look to Altec's Stonehenge I ( II ) cabinets for some inspiration .

They are tallish & narrow ( taking up less foot-print ) .

Since they are more "pipe profile" than typical cabinets, I would think they could excel at giving a working MLTL tuning .

( You'll need help from others for the particulars on MLTL tunings ),

Suffice to say ( once implemented properly ) the MLTL provides one with a lower / deeper bass output ( than is normally accomplished with helter-skelter duct locations ) .

Functional MLTL design is generally considered to be proprietary knowledge requiring some possibility of money changing hands . I would still pursue this avenue given your requirements .

 

[mhardy6647]

Asymmetrical, and not Altec's only venture with non-symmetric horn designs.

I ain't no expert in horn theory. But, i'd opine that asymmetry in the horn path elongates the acoustic center which eliminates the on-axis peaks(or at least some of them) which are characteristic of so many other vintage horns.

FWIW, 32B's are my daily drivers currently.

Heh -- I am pretty happy with the EMILAR EH500-2s -- so it's probably a good thing that I don't have access to a pair of 32Bs, if you catch my drift...

 

[mhardy6647]

Gary,

I would look to Altec's Stonehenge I ( II ) cabinets for some inspiration .

They are tallish & narrow ( taking up less foot-print ) .

Since they are more "pipe profile" than typical cabinets, I would think they could excel at giving a working MLTL tuning .

( You'll need help from others for the particulars on MLTL tunings ),

Suffice to say ( once implemented properly ) the MLTL provides one with a lower / deeper bass output ( than is normally accomplished with helter-skelter duct locations ) .

Functional MLTL design is generally considered to be proprietary knowledge requiring some possibility of money changing hands . I would still pursue this avenue given your requirements .

Well -- there is http://quarter-wave.com/

 

[bowtie427ss]

I have bought and sold so many Altecs over the years and can't remember all of them. Didn't you get your 9849s from me?

Yessir.

After new caps and a little tweaking, they are some of my favorite Altecs.

 

[gamalot]

Yessir.

After new caps and a little tweaking, they are some of my favorite Altecs.

I liked them a lot! Big sound from a rather small Altec. That is what I am shooting for now but even a smaller cabinet if I can figure it out. Kind of like stuffing 10 pounds of fertilizer into a 5 pound sack but I do want to use these 414s and the 32B horns.

 

[EarlK]

Some ( over-sized ) plans ( to modify to your needs ) ;

You'll want to track down a larger version of that second pic ( since it's just a "teaser"in low resolution ) .

 

[twiiii]

A pair of 414's in a 8 cu ft infinte baffle will reach 30 hz, will be well damped with out blooming or sounding sloppy. I admit you'll loose a couple db sensitivity, the bottom octave will be so much better. You'll have to acquire a second pair to have a pair of your version of Altec's very successful Carmel. I sealed the openings around the horn and stuffed the box full of fiber glass. I wish I had had 802 drivers with modern diaphragms and had under coated the horn. I might have kept them. They worked great with my MA 230 and then My C-22 and 240.