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Altec votts

Where best to crossover the H811 ? that remains a contentious issue / & will likely remain that way no matter what data is presented .

- Here's some FR & Group Delay data on the Emilar EH-500 radial horn ( driven by an Altec 288-8K ) . This is my stuff but the ARTA pic is Jmmlc(s)' manipulation of my file .
- The Emilar horn is quite close in size to the H811 / though it lacks the Altecs' mouth vanes .
- Emilar literature states that their horn has a 500 hz flare rate ( the GD spiking at 500 hz would support this claim ) .
- Those who maintain that the H811 horn is best used above 1200 hz can see their assertions supported by the GD curve ( for this horn ) .


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- I use this horn/driver combo down to 700 hz with no audible ill effects . Of course, in the home setting that mine are used in , "real input" equates to very low voltage .
- "Horn-Honk" would likely become a problem if I used this combo live for SR work / in fact / I would expect it to occur in that FR area ( where GD comes up off the mat and then climbs to it's maximum ) .

>< cheers :)
 
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I didn't mean to be an ass with my last post fellas, just didn't wanna send the OP down the wrong path. It's his first experience with VOT's, which can be a bit overwhelming and confusing at first.
 
A7 Project

Hi Guys,
I am new on the AK forum and I am also starting an A7 restoration project. I have been posting with several members here on other forums, so I feel I already am way ahead in my project.

I have 825 cabinets with 902-t compression drivers, 511 horn. I have 418 bass drivers that I just sent off to GPA to be reconed to 416B's. I am also using an Eminance 800 Hz xo. All knowledgeable people I have talked to recommend crossing at 800 Hz. I also have a pair of 846B Valencias. The 846's are original. 416's with 811 and 806's. They also cross at 800 Hz.

The Valencias sound great, but I will know better when I return with my restored McIntosh MX110, and MC240. I am going to Knoxville to pick them up from Tom Manley after Terry finishes with them. I am EXTREMELY excited about this project. I still don't know where I am going to get the money to pay for all this, ha. I will post pictures when I figure out the process.

Good luck to the other guy with his project. Believe me, these guys know their stuff. You are getting great advice...
 
bowtie427ss said:
I didn't mean to be an ass with my last post fellas, just didn't wanna send the OP down the wrong path. It's his first experience with VOT's, which can be a bit overwhelming and confusing at first.
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You've got that right. lol There is a lot more to em than i thought. But im learning. Only way to learn is to jump right in i thought.
 
Here are the pics i promised dgwojo. Just applied the first coat of paint to cabs. gotta take my time its a little cool here. The 515s are newly rebuilt, never been fired up yet. Everything has been gone through and rebuilt by spectrum sound, and none of it has seen any use yet, since rebuilt.
 
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Todays progress, paint done, woofers in, screens touched up and replaced. Horns halfway installed, cant find anything to hold rear of driver up, another trip to lowes. :sigh:
 
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LOOKIN' GOOD!!! You can go to the local Home Despot store and buy some flat metal stok and easily hand fashion you some horn bracketrs. I am not much of a fiberglass fan I would be tempted to experiment with open cell foam in those cabs!!
DC
 
Cripes, you're into this aren't you? Good progress, my man!

I can't help myself, why the paper on the garage door windows?
 
This is what mine use for brackets. Sorry for the sideways pic.
Steve
 

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You can find original horn brackets for the rear support on the bay, but they usually run around $50 or $60 for a set of originals.. or.. make your own as shown..

Something else you may consider is closing off the backs of the horn space inside the boxes.. the piece where the woofer mounts. Take that all the way across the box, and support with 2x4's on the sides.

This will help take some of the "ring" out of the box and give added support, while helping to lower the freq response of the LF... Some people even go so far as to fill the space behind the horn flares with expanding foam or sand.
 
theebadone said:
Here are the pics i promised dgwojo. Just applied the first coat of paint to cabs. gotta take my time its a little cool here. The 515s are newly rebuilt, never been fired up yet. Everything has been gone through and rebuilt by spectrum sound, and none of it has seen any use yet, since rebuilt.
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Hey, thanks for posting the pics, I don't know why so many re-coners insist on using the stiffer beige musical instrument spiders for 515's, light gray/black ones were stock on the newer series of 515's (515b), the cone suspension was not at all stiff with the dark ones. The good news is that they'll probably handle a ton more power but at a loss of efficiency and possibly some low end. Dave.

GPA reconed these for me after I restored the rusty frames;

Altec_515B_GPA_20060211_09.jpg


Altec_515B_GPA_20060211_08.jpg


Altec_515B_GPA_20060211_07.jpg
 
OK, I will try to answer everyone. The windows in the garage door are blocked out because that where i smoke my weeds, lol. I get paranoid when i smoke that stuff. Just kidding, we had a thief next door so i figured he didnt need to know whats in the garage. Those are some nice looking 515s dgwojo. I'm done with em for now i still have some tweaking to do. One question, why didnt anybody warn me about how LOUDDD these things are. just kidding, They sound great. heres finished product AND THANKS EVERYONE FOR THE HELP AND ENCOURAGEMENT.
 
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dgwojo said:
GPA reconed these for me after I restored the rusty frames.....
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Very Nice...... I've considered doing something similar. What did you use for paint? Did you spray it yourself, and did you leave the area where the spider glues to the frame bare, or where the motor attaches to the frame?
 
Tryin to make 40 year old abused plywood look good is a chore. I used bondo for filler which works great, just lots of sanding. Paint is just wood, grey primer, final paint is grey enamel, its all i could find, and its all spray paint. Yes i left those bare for now thats a later project. My back, arms hips and legs are hurtin from this project. So if you start a project like this, have plenty of pain pills on hand. And yes i did ALL of the work, i sprayed the cabinets, cant you tell. lol
 
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