Heathkit AS-48s (JBL Athena 99) - what to do with them?

[canuckaudiog]

Hey AK!

When it rains it pours.. after going from zero pairs of JBL speakers, I immediately acquired two within a day of each other. The second set, a pair of Heathkit AS-48s, popped up at a too-good-to-pass-up price so I jumped at the chance to get them.

For those not familiar, the Heathkit AS-48 is a made-for-Heathkit, JBL S99 Athena. However, from what I understand it uses an LX8 crossover, and I believe that's different than the S99 and is actually more like the C53? Regardless, the crossover point is 2kHz on the LE20-1 tweeter, and the LE14A runs full range.

I'm currently debating what to do with these. Certainly, step 1 is going to be refoaming the woofer and having a listen to these as they are. However, it seems like taking the tweeter out and using something else instead is a worthwhile endeavour with these. Considering what I paid, I'm in a good position to turn these into a more listenable pair of speakers, rather than focus strictly on their value.

That said, I've done tons of research into what I could possibly do. The really troublesome part seems to be finding a mate for the LE14A woofer. It is a higher sensitivity driver (92-93dB) that wants to be crossed over at around 800-1kHz. Using this as a two-way means finding a tweeter that can reach very low, and not many of those exist. In my research I haven't found good candidates for this. Does anyone here potentially know of one? This would be my preferential way to go.

The second option is the econowave route. My issue here is woodworking - I don't have the means to modify the cabinets to fit in a horn. This is a desireable way to go because it solves all the problems and would sound awesome, plus the crossover is already figured out.

The third option is to simply leave them as they are, original with warts and all. However, looking at the drivers and the crossover, I cannot fathom how these don't have significant problems. The tweeter rolls off early and then the woofer really does not want to play up to 2kHz, and that tweeter doesn't do so well down below that. I'm sure if I tried to lower the crossover point to around 1.5KHz, it might actually damage the tweeter, so leaving them original seems like I would have a subpar pair of speakers.

The fourth option I am considering is turning these into a 3-way, swapping the tweeter for a mid, and then using some sort of a "super tweeter" (like the Realistic super tweeter, since it's sensitivity is about right) on top of the cabinet, using the 900Hz econowave crossover and then redesigning the midrange circuit for the new driver. I haven't really looked into this but might be one option.


(Not my picture but, same speaker)

Any thoughts are welcome!

 

[Nyjblbob]

It boils down to how much do you want to spend?
JBL offered the Le14's paired with the 175dlh horn driver combo, but with a different 1200cps x-over. and they are not cheap$$$
you can use the Le20's as tweeters only adding any version of the Le5 Mids and swapping the x-overs
from most early,JBL 3 way Bookshelf x-overs.
If you can't correctly cut the baffles, just add a tiny pair of cabinets just for the mids and tweets
and put them on top of your cabs.
Or you can do the econowave. a proven design and the Le14's are a favorite woofer for it.
and your cabinet is already tuned for it.

 

[canuckaudiog]

It boils down to how much do you want to spend?
JBL offered the Le14's paired with the 175dlh horn driver combo, but with a different 1200cps x-over. and they are not cheap$$$
you can use the Le20's as tweeters only adding any version of the Le5 Mids and swapping the x-overs
from most early,JBL 3 way Bookshelf x-overs.
If you can't correctly cut the baffles, just add a tiny pair of cabinets just for the mids and tweets
and put them on top of your cabs.
Or you can do the econowave. a proven design and the Le14's are a favorite woofer for it.
and your cabinet is already tuned for it.

Out of all the choices, it seems like going the Econowave route would be the least expensive with the best results.

Perhaps that is the direction I should go.

Am I able to put the horn on top? Or does it need to be close to the woofer to work best?

 

[Nyjblbob]

First I think you should read the Many recent At least the last 2 pages on the Econowave posts on this Forum. All of your questions are addressed.
But Yes you can place the horns on top or better yet just make a simple Baffle or box for the horns, they don't put out any usable energy
from the Backs. But as some have stated the Le14's really can use a bigger cabinet 3-4 cu ft for better Bass extension.
That being said, if using the stock cabs, For better Bass support they should be on the floor or Solid Risers. But you want the horns at ear level.
One last thing to get some added Bass support
from your cabinets is flip the cabinets upside down so that the port is close to the floor,
and the woofer is closer to the horn. then just tilt the horn up .I will add
that with a 1500cps X-over point the woofer would be putting out Mid-range frequencies.
So yea you would want them up a bit, or tilted back
Again you have some choices to make.