Project '79 LS Restore

[kzr750r1]

Heresy rears. Like the speakers too. Will be side surround once I figure a decent stand for them. Need to be up 3' or so.

[jhoak]

Are those Heresys walnut? I'm going to have a pair of slant risers in walnut available in a week or so.

[kzr750r1]

Yep they are Walnut with stock flat riser. Would like to see what you have to offer. A set of slants would be nice. May not be needed tough as I have to raise them off the floor at minimum 2'. Serious furniture issues.

The LS is going to need a taming to work in this position. My intent was to see if I like these, I do like them. But what I'm finding (quickly) is they are way to harsh for this application.

But take them to a 2 channel arrangement and they start coming alive.

You guys have covered so much ground on this forum I have many years of catching up with possible mods and outcome.

Bobs 4500 cross over looks interesting. But I'm not sure it's going to cover all my expectations....

Reading and thinking and listening.

[Blvdre]

Al K's Universal design allows you to change tap settings w/o having to alter the x-over components.

[Blvdre]

Double post

[Johnny's Jill]

If your scalas sound harsh the best thing you can do is replace the mid horns with wood tractrix horns. I use gothovers horns, but any wood tractrix will be a huge improvement.

second if you still need the scalas smoother replace the AA crossovers with ALK Universal or Extreme slope.

Craig

[kzr750r1]

Horn mods are not in my future on these speakers. ALK universal seems to be a good fit for my needs. The only issue I see is they will be power hungry. But if it allows the flexibility I need to adjust with the current drivers with the K400, then it may be the direction I take. Trying to avoid costly experiments.

[Guest David H]

Horn mods are not in my future on these speakers. ALK universal seems to be a good fit for my needs. The only issue I see is they will be power hungry. But if it allows the flexibility I need to adjust with the current drivers with the K400, then it may be the direction I take. Trying to avoid costly experiments.

The ALK universal crossover is really no more power hungry than the AA you are using, I am sure you will be very pleased with them.

BTW, horn mods are no more costly than the crossovers, and both are a signifigant improvements.

Enjoy, Dave.

[kzr750r1]

Thanks Dave. I just really don't want to carve cabinets or even take the grill cloth off yet. They are in really good condition considering their age.

I'm considering just dropping the tap and placing a resistor as a short term fix. Just can't afford new crossovers at the moment. Still need to confirm values from what I've read so far but it seems another compromise to try.

I was hoping for more bass throw from these. So it seems I need to take the squawker down at least two fill steps on the transformer.

And the beat goes on.

[Johnny's Jill]

I just really don't want to carve cabinets or even take the grill cloth off yet. They are in really good condition considering their age.

You dont have to modify your cabinets to install gothovers lascala horns, they are a bolt in.

Craig

[kzr750r1]

Didn't dig into his site till now. Thanks for the heads up, horns those look nice Dave.

I have to be careful in what changes to take as anything must be reversible. I'm looking for any extra parts to be part of a new speaker like a cornscala scenario.

[Guest David H]

Thanks for the heads up, horns those look nice Dave.

Thank you.

I'm looking for any extra parts to be part of a new speaker like a cornscala scenario.

Good call, I love Cornscala's.

Dave

[kzr750r1]

Dropped the T2A Tap to #2. Didn't see a measurable difference in the ohm rating. They sound better for sure. Tried an AB comparison with the other on #4. Tried #3 but felt the #2 was a best so far.

Yeah I know change that horn!

With the tap now on #2 am I causing any issues for the drivers or amp? Each tap change didn't modify the impedance from what I see. Or am I missing something about the need for the resistor to balance.

Reading deeper about mods to the AA and note Al kicking himself for all the suggestions.

Noting the options offered by ALK so far what else should be added to the following?

1) Add a 1.0uFd capacitor in parallel to the two 2uFd.

2) Remove the woofer inductor screw and or change the inductor to a "2.4 mHy air core woofer inductor".

3) Ditch the zeners. judging from what I've read they are not needed with the tweeters on board and can cause distortion at high levels. I turn it up somtimes. Will have to do some more vibration damening. Noticed the text on the TV (projection) vibrating.

4) Swamping resistor? Would 10 ohm work for this stack of compromises? If so where is it placed, not clear on this part yet. Would like the ability to move the attenuation around.

Looking at doing these crossover mods just to clean up this before trying a new/different design. Well see where this leads me.

Thanks for your assistance thus far gents.

[kzr750r1]

Can anyone confirm my plan of attack on these La Scala? I have another pair of problems. Found some Cornwall II 1985 from the origional owners son going off to college for $400. Could not pass them up.

So this means for sure any major mod budget for the LS is out the window. At least till I rid myself of the 901s.

Would like to address the questions above so I can at least clean up the AA Network for now.