Replacing 15" Drivers in my LaScala's

[kdvois]

I am looking to upgrade my 78 LaScala's. The first upgrade I would like to make is to the 15" drivers then later my networks. I am looking for something thats going to give me some big bass, I do not have a sub. I am using the original AA crossovers but will be upgrading them in the future. Any sugestions?

Thanks,

K.D. Vois

[mungkiman]

It's not the advice you want, but get a sub.

[Mike Dubay]

There has been much discussion on "porting" La Scalas. A tuned port volume is added to the bottoms of the bass bins. Search for "ported La Scalas" in this form. This would provide more bass than any woofer replacement. Good luck!

[Coytee]

It's not the advice you want, but get a sub.

I agree with Mungkiman. As I understand it, the woofer in the LaScala is very specific to that cabinet. You can put a more heavy duty driver in there for more power handling BUT...you really won't gain any lower output.

Get a sub and maybe investigate different ways (wedges, extra panels?) to stop the sidewalls of your speakers from resonating. Stopping them from resonating alone, might bring a smile to your face with the apparent increase in bass output (still the same but now you can hear it better).

When you upgrade your crossovers, not knowing how exoctic or wild you want to go (or pay), you might also look into taking your LaScala down to a 2-way unit and add either the K510 or K402 on top and make it a "JubeScala". Do a search on JubeScala and check it out.

I've replaced the AA crossovers in my 1979 LaScalas with some of Al K's extreme slope crossovers. The speakers are still stuck in a closet downstairs waiting to be pulled out. Once I get to them I will probably sell the crossovers and go the JubeScala route with them. I have three LaScalas and I'll probably do the larger K402 horn on one of them and the smaller K510 horn on the other two. Using some of the proceeds of the ES networks and drivers to help offset the bigger upgrade.

At least, that's my current thinking.

[sootshe]

I would disagree about using a sub, as to my ears it muddys the sound & doesn't give a true bass definition....on top of that it's very hard to integrate with your main speakers. I used the ported box underneath the LS & now have good output down to 30Hz which is plenty low enough for all types of music. If you want to shake the walls with subsonics then maybe you will need a sub. You definitely need to brace those side walls to tighten things up.

An upgrade to the Crites cast woofer will give you a little more output at the extreme lows (more than you might think) & the ALK Universals or the Extreme slope if you can afford them are the way to go. Having the ability to cut back the mids is a real bonus.

When you've done that you should think about getting rid of the K400 & using the Trachorn....it makes a huge difference.

Good luck.

[J.4knee]

For the most part replacing the driver will not yield much if anything in terms of low frequency extension. The bass horn is only a 100 Hz horn after that your bass performance is a from sealed enclosure. To extend your low frequency response you need to either add a sub, The THX Ultra II subs will work extremely well with a set of La Scala's......or you can port the bass bin. Adding bracing to the bass bin to abate the resonance will require some re-voicing.

[Daddy Dee]

Replace the caps in your networks. They don't have to be expensive. Caps over 30 years old suck big time. You won't know what you've been missing until you get those done. First Priority, IMO.

[mungkiman]

Replace the caps in your networks. They don't have to be expensive. Caps over 30 years old suck big time. You won't know what you've been missing until you get those done. First Priority, IMO.

Absolutely!

[JohnA]

"Upgrade" is a funny word. What are you trying to accomplish?

IF your La Scalas have square magnet K-33-Es there is nothing you can do but to increase power absorption capacity of the woofer. Bob Crites' cast frame woofer is good for 150 watts, ~$150. A K-43 is good for 250 watts, ~$250. A JBL 2226H is good for 600 watts, ~$600. There will be minor changes in frequency response for each woofer.

IF you want deeper response, 2 or more subwoofers are required. You'll need BIG ones to match the low distortion of the La Scala's bass horn. The bass horn is a hybrid, of sorts, with a 70 Hz flare and said to have a 125 Hz mouth area.

It is also possible to add some low bass with djk's cabinet porting. It works best with a K-43 woofer, but probably should have an electronic high-pass filter to protect the woofer from excessive cone travel. Some here have done it and posted testing that proves it works, but it is a lot of work for a weak extra octave.

The age of your crossovers make the condition of the capacitors suspect. The Type AA is one of the better, longer-lived crossovers Klipsch used. Replacing the capacitors with new, nice ones would increase the highs in the squawkers and tweeter, making them sound cleaner. It may also reduce distortion. It sounds like it does to me. You could also replace the woofer inductor with a large gauge, air-core inductor. I have not done it, though I bought new inductors 7 or 8 years ago. Mr. Paul once wrote the woofer inductor was linear up to 63 watts, so I've never thought it worth the effort. If you are careful with the power, you can disconnect one ot the KLiP diodes and disable the tweeter protection. It will reduce the hash and grit the protection circuit adds at high volumes. I would call these changes "upgrades".

We have developed several Type A crossover variants on the board. Al Klappenberger has designed excellent Type A Universal and very high end Extreme Slope crossovers.

Also look at adding damping material to the squawker horn. I used Dynamat. Rope caulk works, too. Verify you need it by touching the squawker horn while playing a woman singing. This will also be an "upgrade".

To reduce cabinet ringing, I stuffed the upper cabinet (around the squawker horn) very tightly with polyester pillow stuffing from Walmart. Rap the top center of the cabinet to verify you need it.

Help us help you by telling us what you dislike and want to "fix".

[kdvois]

Thanks guys for all the great info. My main concern was to get some thumping bass and kill some of the high tones within this speaker without having to resort to buying a sub to do it.

[doittoit]

I have had a pair of 1984 LaScalas since new. Earlier this year replaced th tweeters with the Crites CT125 and the crossover with the Crites Type A/4500 crossover. I just recently added a JL Audio F113. Tons of nice tight bass down below 20Hz at full volume ( my room correction is turning down the bass below 20 Hz to make it blend right), mate up to the LaScala's like they were made for each other ). Still considering replacing the woofers in the LaScalas as they have been in service since 1987 ( blew one in 1987 ).

If I had it to do over again, I wouldn't deviate. You can't get deep bass out of the LaScala, it just isn't made for it. As for the porting option, you will lose the nice tight bass you have to get a sloppy lower octave ( this is just my opinion here ). Also, from what I've been reading, the cast-basket Crites woofers may get you a little better bass, but some people are having to gouge out wood to make room for them in their LaScala's. I may also replace my mids sooner or later ( seems to me that 25 years is a lot to ask, but I'm not sure how long they should really last).

[Marvel]

As for the porting option, you will lose the nice tight bass you have to get a sloppy lower octave ( this is just my opinion here )

You won't lose the tight bass if you keep the port length to 7". It will still sound tight, and give about a 3db increase in bass output.The original 10" port length will make the bass a little looser.

Also, from what I've been reading, the cast-basket Crites woofers may
get you a little better bass, but some people are having to gouge out
wood to make room for them in their LaScala's.

Most grind off some of the frame or use a bandsaw to trim off the frames so they will fit.

[Blvdre]

Thanks guys for all the great info. My main concern was to get some thumping bass and kill some of the high tones within this speaker without having to resort to buying a sub to do it.

Although they don't reach that low, the LaScala bass will certainly thump. It sounds to me like you're unhappy with the tonal balance of your LaScalas, in that they're tipped to the high end. This problem can be solved by attenuating the mids and tweets via the crossover.

[JohnA]

Thanks guys for all the great info. My main concern was to get some thumping bass and kill some of the high tones within this speaker without having to resort to buying a sub to do it.

Have you placedthem in the corners? That will boost the bass as much as possible. It will be solid to a little below 60 Hz.

[PrestonTom]

Thanks guys for all the great info. My main concern was to get some thumping bass and kill some of the high tones within this speaker without having to resort to buying a sub to do it

By all means, go ahead and refresh the caps in the crossover. It is cheap and will make some improvement.

However, this will do absolutely nothing for the bass response (which was your original complaint). For some unknown reason, the capacitor solution is frequently offered as a tonic for all ills. The caps are affecting a portion of the spectrum that is a few octaves away from what you are interested in.

You should definitely follow through on John's suggestion about room placement, IMO.

[LenE]

Replaced all the caps in my 1992 Lascala's with ClarityCap's and the differance is massive.

Slot ported the base with 4mm thick cork washers, cheep and easy and get "stong" output at 40htz.

LenE

[Guest " "]

going to a steeper sloping network will create the allusion of more bass relative to the other parts of he music spectrum because steeper sloping networks do a better job of separating the sound. In a non better job senerio, what happens is that low order crossover networks slope very gently and a lot of bass gets thru and into the mid driver circuit. The auto-former shorts most of the leaked bass signals to ground. You want to capture that and make sure it goes to the woofer instead. Hence the need for a steeper sloping network. Your not going to get sub woofer quality bass by replacing the woofer. The bass horn is really a very good midbass horn. Your not going to much below 50hz but heat. Ports or slots also help with the illusion of better bass. But at high volumes, ports and slots fart a lot.

[tfoust]

I have read many of the threads discussing the limited bass output of LaScalas and I haven't found an explanation for it. If I'm covering old ground I apologize. I seems to me the elements to be considered are the enclosure, the driver and the crossover network. Could not any one or all be changed to perform the same way as Cornwals or K-horns? I like my LaScalas but I don't like having to deal with their size AND a sub to get a broader specrum of sound.

[tromprof]

I have read many of the threads discussing the limited bass output of LaScalas and I haven't found an explanation for it. If I'm covering old ground I apologize. I seems to me the elements to be considered are the enclosure, the driver and the crossover network. Could not any one or all be changed to perform the same way as Cornwals or K-horns? I like my LaScalas but I don't like having to deal with their size AND a sub to get a broader specrum of sound.

How low a horn speaker will go is determined by its length. A trumpet will never go as low as tuba, it is too short, and the same goes with horn speakers. The difference between the K-horn and La Scala is the length of the bass horn. My experience with the La Scala is placement is key to maximizing the bass. Good corner placement yields great bass, but it does not go all that low. I added a horn sub (tuba table) to mine; the transition is seamless and I now have great low bass as well.

[Islander]

If you want deep and solid bass, you need a sub.

It's a bit of work to find its ideal position and phase and level settings, but once it's done, you'll have good sound from top to bottom.

La Scalas may look big, but they were designed to be "portable" for stage use. If you wanted deep bass from them, they'd have to be much much larger. That's just the physics of working with horn-loaded speakers.