Budget woofer system with Horn

[gwho]

Hello everyone, I just joined this forum to get a better understanding of Horn speakers. I've mostly listened to full-range electrostatic speakers for the last decade or so. I am intrigued by high efficiency speaker systems that support a wide dynamic range. This is the one failing of electrostat speakers and I'd like to see how a horn system sounds with a low wattage tube amp. I was going to buy a Klipsch CF-4 speakers but on a whim I purchased a pair of Altec horns off of Craigslist. I'm not much of a speaker builder but was wondering if there is a cost effective woofer system (that has been tried and documented) with a reasonable foot print that integrates well with an altec horn. I've looked on ebay and a built box such as an Altec 8256 is quite expensive (shipping is a killer) plus the drivers are 30 years old. As an alternative, there are a pair of Santana speakers with the biflex woofers that are local that can be had for a reasonable price. I realize the biflex system is a full range but this could support integration to the horn if the low frequency is a adequate. The only thing I don't know about is the low end on the Santana's. Also, would there be a significant efficiency mismatch. If you think the biflex would work I could always add a subwoofer for the low end. Also, I am not opposed to finding similar JBL or other bass components that might work. I can see the price of this escalating to the point where I would be better off just buying something like an Altec 14, 15, 19 in which case I'd sell the horns and buy the real thing. I'd like to thank everyone in advance for any input they might provide.

Regards,
gwho

[more10]

Which Altec horns did you buy? Driver?

Even if you buy a woofer box, you will have to deal with the crossover. Construting passive crossovers for horns is difficult. Active crossovers are simpler, and you can combine solid state amps for bass with tube amps for the horns.

If you just want to listen to your system, buy a complete working system. If you want to do this as a hobby, keep your horns and get the other stuff you need. This is great fun, you will not regret it if you keep the horns.

[gwho]

Thanks for the response. I was wondering if I worded my question wrong. I realize that many DIY designs can supercede vintage speakers that were designed before the pc was invented. My assumption is that this would be true for the woofer section of a horn system yet by having the horns keep that vintage sound. The horns I picked up are listed as Altec 288-8k on the back of the driver. The horn part of it is quite large and I don't know if I would want to use it unless someone tells me that it is good. My wife looked at these things and was aghast. I really would like something smaller. The horn is a MR94a and measures almost 3 x 2.5 feet. There is a metal adapter from the driver to mate to the horn. They look to be in good shape and were pulled from a church. I have a couple of Rane analog crossovers and plenty of amplifiers. I would likely not use a passive crossover as part of the project. Would I be better off waiting to find a vintage Altec woofer box or have there been some good woofer box designs that would mate with the horns I picked up that have tested. I don't mind building a box that's the fun of these projects especially if it improves what was the state of the art. I've attached a picture of the horns.

[gwho]

As I mentioned previously, would you think that the Santana could be crossed to the horns and give a good sound. Would the biflex driver have sufficient punch and low frequency extension to match the horn.

Thanks
gwho

[Mr. Widget]

I would have to say that I agree with everything that more10 said.

Building DIY speakers is extremely gratifying, however it is not a trivial pursuit and to actually end up with something better than what is commercially available takes a lot of experimenting and experience.

I guess what I'm saying is don't hesitate to explore your options however don't expect success right away.


As for what you should do with those horns, I would investigate our information in the Altec area and I would go to Todd White's website and see what people there can offer. Those horns are not terribly vintage. They're actually fairly late Altec production. Beyond that I know nothing about those horns so I can't offer any practical advice.


Widget

[gwho]

Thanks for the advise. Could you suggest one or more altec boxes with drivers (or other brand) that I should keep my eyes open for that have great dynamics and punch. I will also take a look at the cite to learn more.

gwho

[more10]

These are Mantaray horns. I have no experience with these but they should go low.
Altec 288-8k, low frequency limit is 500 Hz. Usable from 800?
Technical Notes Vol. 1, No. 4 Constant Directivity Horns, JBL says cutoff at 800. I don't trust this figure.
Installation and service instructions

I believe you can find smaller horns with a practical lower frequency of 800 Hz.

Finding a 15 inch driver going up to 800 Hz is no problem at all. Deciding which one you want is more difficult. I believe Altec 15 inch drivers cost more on ebay than JBL. Building a vented enclosure going to 800 is difficult since the port will radiate midrange frequencies unless cleverly damped inside the box. JBL 2226 should be easy to source and sounding good as well. You will get plenty of cabinet designs for it

[Lee in Montreal]

Mantaray and Altec 817 cabs

http://upload.review33.com/images/20...2130077584.jpg

Plans
http://www.audioheritage.org/vbullet...at-are-correct

[more10]

Of course. 817 spec sheet. Will not make the wife any happier though.

Or 816 single driver horns.

Found this thread: Should Altec 288 compression drivers sound like this? (ringing)

[more10]

Altec Lansing GPA 515 515-8G NEW. 300$ is a very good price.

[Lee in Montreal]

Will not make the wife any happier though.

When the man has balls big enough to bring a set of Mantaray horns home, we already know that wifey has no say about what he does with them. With the horns, of course. Not the ballz. ;-) But hey, if (relative) compactness is needed, then may I suggest twin JBL 2225/2226 in an 11cft bass reflex enclosure. Roughly 36" wide x 24" deep x 24" high.

[gwho]

First, I have the balls to bring the horns home but not in the house. The first thing the wife said was "don't you even try to bring those in the house". The kids thought they were pretty cool though (they are teens). I think some of the responses were quite helpful in giving me some direction. More10 thank you for the technical notes on the driver I have. I will read up on it. It appears that I have the MR94A, 24654 Throat, and 288 driver. From the diagram it appears that an 805B or a 1005B horn will work with my driver and should result in a much smaller form factor. Lee in Montreal thanks for the pics. That system looks pretty cool. It also looks pretty big. Would a single GPA 515 be sufficient match for the 288-8k? Is there an established box design for it that I could copy? Also, did the GPA 515 come in a box that I might find someone selling locally? Similar question to the twin JBL 2225/2226. Did it come in a JBL box that might be had locally used at a good price? It seems that the most common Altec box with drivers being sold on ebay were the 8256 with two 15" speakers.

Much appreciated
gwho

[more10]

Try to swap the horns for multicells:



The big ones look really nice

[gwho]

More10 the multicell horns do look nice! I did some searching and it appears that what I have lends itself most to building an Altec A6. I tried to find some discussions on the A6 but there is not much out there. It appears that the A6 is not well thought of compared to other voice of the theater speakers. The A6 includes the 8256 with 3156 drivers. If I found a pair of these are there any significant issues with the 3156 that I should look for? Do the 3156 hold up well? I assume they will probably be about 20 years old. I found this picture and I believe it has the horn I have on it. Does it make a significant difference which way you mount the horn? As shown the slot is vertical.

As usual thanks for the input
gwho

[Lee in Montreal]

Gwho - Yup. Slot must remain vertical for optimal dispersion.

http://i443.photobucket.com/albums/q...t/CIMG6768.jpg

If space is a limitation, you can make a cabinet with one single 15" driver. I have the JBL "equivalent" of your Mantaray and use it for home duty with a single JBL 2226 in a bass reflex enclosure. The 2226 works fine down to 40Hz. I have an 18" 2245 for infrabass. Very often I don't even power the 18" driver. For best integration I also have a digital crossover and multiple amps. I ended up with a very simple two-way system.

To reduce the visual impact, you can make your cabinet narrow, yet deep. You need depth anyway as your Mataray will most likely require 36" depth. Build a 36" deep x 18" wide x 24" tall cabinet. Looking from the front, it will look "tiny" at 18" wide x 24" tall. The combined height of the bass cabinet and Mantaray will be no more than 48". What's the Mantaray width?

http://img.photobucket.com/albums/v6...psdf7728b2.jpg

http://img.photobucket.com/albums/v6...ps56463075.jpg

http://img.photobucket.com/albums/v6...psb8c05d3b.jpg