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Heathkit AS-101: Thrift Store Score!

Did anyone else find a name scribed on their horns? I'm wondering if it was something done in the factory, or by the guy that bought the kit.

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Yep, that looks much nicer than the tobacco stained finish that they came with. What was HeathKit thinking? That original finish seemed popular back than, I see it on old furniture in thrift stores regularly. Yuck. Someday I hope to refinish my set.
Did the front motorboard come out without damaging the grill cloth?

BillWojo
 
BillWojo said:
Yep, that looks much nicer than the tobacco stained finish that they came with. What was HeathKit thinking? That original finish seemed popular back than, I see it on old furniture in thrift stores regularly. Yuck. Someday I hope to refinish my set.
Did the front motorboard come out without damaging the grill cloth?

BillWojo
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It came out without damaging the grill cloth. The motorboard is not glued in, but there are 4 screws at the top that are obscured by the board that the horn mounts to. I ended up drilling small holes, so I could stick a screw driver through it. Other than that, dissembling these cabs was a piece of cake.

I think that I'm going to take the original grill cloth off. Its a really dense fabric. When I first hooked the speakers up, I could see the fabric billowing about a 1/2" as the woofer tried to breath through it.
 
I'm planning on using some Realistic super tweeters with these speakers. I was thinking about jumping connections from the other side of the l-pad back to the two extra speaker terminals (tapping into the signal between the L-pad and the high frequency drivers).

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This way, the L-pad will attenuate the horn and the super tweeter. The Realistics are crossed with a 2mf capacitor as 1st order crossover. What do you think? Good idea, or bad idea?
 
Check out all the upgrades on the Valencia's. They apply directly to that speaker.
If you like the design of the grill cloth then carefully remove it and and wash it. They should not do that.

BillWojo
 
Ezd said:
Looking forward to learning your thoughts about the upgraded crossovers.
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There is a big difference in the numbers, I'm curious to see how it translates to sound. The old caps are the most out of spec caps that I've ever replaced.

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Fun! My first Altec speaker ever. They still sit in the spare bedroom. I just love the paint they used on the horns/ drivers. Cabs are crapola as everyone mentioned. Some day these will get some nice sturdy cabs when I get around to it. I AM a woodworker.... just a super lazy one these days. LOL
 
Did a quick L/R comparison and the different in sound quality is palpable! This is definitely the biggest difference in sound that I've noticed with a recap. The highs, and lows, of the original speaker sound muted and lifeless when compared to the modified one. I can't wait to get these guys in the house and hooked up to my Yamaha CR-1000 :D

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BillWojo said:
They sound much nicer on tubes.

BillWojo
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That does bring up a question. So Heathkit states that you can drive these with as little as 10w. But, what would be a reasonable wattage for a tube amp for these? I see a lot of low power vintage stuff on the bay that isn't too prohibitively expensive.
 
Try with a 15W pp amp that should be more than enough, I have a pair of 604E's that I use 5W SE amplifiers for them and I can play loud enough to disturb my neighbors.
 
Riki said:
That does bring up a question. So Heathkit states that you can drive these with as little as 10w. But, what would be a reasonable wattage for a tube amp for these? I see a lot of low power vintage stuff on the bay that isn't too prohibitively expensive.
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I run my Altecs with my Fisher X100B which is I believe around 25 watts per channel, and it's more than enough.
 
Riki said:
Has anyone here ever tried wiring these for bi-amp and using something like a minidsp?
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Never tried it myself but I would think an older big 2-way design could benefit a lot from using a miniDSP crossover (or similar) to get the most out of those very capable drivers. Of course this assumes you get the measurement mic and use something like REW to help design the filters.

Keep up the good work!
 
I've been playing around with filling these cabs with poly fill. I'm using dayton imm-6 to take measurements and the AudioTool app on my phone to generate pink noise and measure. The same amp is used for each test with the amplitude, treble, and bass settings the same (but in some I have the horn turned down, to help my ears focus on the lower end). My results feel a little counter intuitive to what I've read about the general effects of stuffing a cabinet. But, I'm new to trying to quantify something like this. Please feel free to point out the flaws in my methodology.

My conclusion: replacing the fiberglass insulation with open cell mattress topper foam, and stuffing the ports with 4" blocks of open cell foam appears to have shown the most improvement

Baseline: Stock speaker

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Updated: No fill, fiberglass insulation was replaced with open cell mattress topper, ports are open

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Updated: same as above, but I stuffed the ports with open cell foam blocks

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Updated and stuffed with 1/4 lbs per cubic foot

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Updated and stuffed with 1 lbs per cubic foot

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