MDF vs. Plywood for La scalas

[DrWho]

Ultimately it was too expensive. Klipsch builds the doghouses seperately and then they are slid into place of the outer shell (if I'm remembering correctly). So you end up with the point on the doghouse being not perfectly centered - so the side braces need to be custom for every speaker (not gonna happen). Also, 3/4" is right on the verge of being thick enough. In the right conditions, there is no cabinet resonance to worry about, which is why it went unnoticed for so many years. I hope I got me facts straight....after hearing the Lascala II, I wouldn't even consider anything else.

[HDBRbuilder]

PWK tried the braces, they worked, but because it would require a custom fit for each factory produced lascala, the idea was scrapped as being too expensive for production models, plain and simple!

use a four foot long section of solid oak 1x8 lumber...will supply four braces for your pair of LaScalas...JUST SHAPE DIHEDRAL-LOOKING PROFILE INTO THE BRACES FOR AESTHETICS. Trust me, they will look great!

[kg4guy]

Mike what was it about the La scala II's that you like them that much more as not to consider the other La scalas ? Thanks

[kg4guy]

I noticed on Gregs rebuilds he used the braces but put grills on them and that was nice however is there a way of tapering them so they are pointed to match the point on the dog house that might look cool.[^o)]

[seti]

The La Scala II's are the most improved speaker in the Heritage line possibly of all Klipsch. The thicker bass bins just yield better more pronounced bass and you would swear they go down lower than the specs. They are winners!!!

[jbsl]

The La Scala II's are the most improved speaker in the Heritage line possibly of all Klipsch. The thicker bass bins just yield better more pronounced bass and you would swear they go down lower than the specs. They are winners!!!

I agree!

I heard the LS IIs with a Rouge Audio Temptest II 90 watt tube int amp. The LS IIs bass sounded very good at moderate listening levels. Moderate to me is you can still talk to the person next to you without having to raise your voice much.

I also agree that the room can make a difference along with the equipment.

If you have not worked with MDF then go with plywood.

[kg4guy]

I am going with plywood I have a few subs around I can use if I need, Thanks

[ClaudeJ1]

which fills in the 200-300 Hz range and can give the appearance of the bass going lower in the LaScala II, but the bass horn DESIGN is what actually limits the bottom end extension.

This is why I prefer LaScalas with a K-43, which has MUCH better response/articulation in the 200-400 range, and poorer below 100 Hz, which makes the perfect for use with a Subwoofer.

I gave up entirely on LS bottoms when I went to Mid Bass horns with a straight axis. Those give up at 150 hz. but carry the entire vocal range and most guitar and piano to over 1K hz. 180 hz. and below I uses MWMs which blow away any other Klipsch bass cabinet for music or theater.

[DrWho]

Mike what was it about the La scala II's that you like them that much more as not to consider the other La scalas ? Thanks

It's more about what they don't do...no tubbiness, no congested vocals, no resonating toms/snares, less harshness or hashiness in the vocals and piano guitar...to be honest, I would never own lascala I's - even if they were free. I would have no problem owning a Lascala II, however. With a sub, the difference isn't as dramatic, but I'd still stick with the II. As far as DIY and whatnot, adding braces should be fine. I personally would boat tail the braces so that the sound can sneak around easier.

[kg4guy]

Sounds like alot of that has to do with the crossovers as the top of the cabinet is the same K-401 horn K-55 mid new tweeter but with Bobs tweeter it should be close.ALK Universal crossover should correct alot of those issues on the top end of the old La scalas.

[colterphoto1]

which fills in the 200-300 Hz range and can give the appearance of the bass going lower in the LaScala II, but the bass horn DESIGN is what actually limits the bottom end extension.

This is why I prefer LaScalas with a K-43, which has MUCH better response/articulation in the 200-400 range, and poorer below 100 Hz, which makes the perfect for use with a Subwoofer.

I gave up entirely on LS bottoms when I went to Mid Bass horns with a straight axis. Those give up at 150 hz. but carry the entire vocal range and most guitar and piano to over 1K hz. 180 hz. and below I uses MWMs which blow away any other Klipsch bass cabinet for music or theater.

You confuse the heck out of me. You insist on K33's in your MWM's but put K43's in LS for home use.....[8-)]

[HDBRbuilder]

Well, let me clear up this mdf onLaScala deal, once and for all.

Until the LaScala II came out, made out of veneered MDF, and with sides of 1" MDF, the LaScalas were made out of 3/4" plywood as they had been for over 40 years.

Soooo...Why go with the MDF?? A better question to answer might be why come out with the LaScala II??

Most of the LaScalas being produced by Klipsch for the last few years before the LaScala II went into production were being used as home speakers, not as stage speakers. In addition, fewer people were buying the much more expensive Belles simply because they could get the LaScala cheaper, AND because the top end of the LaScala was an identical voice match to that of the K-horn which is obviously better for using the LaScala as a center channel between two K-horns. Lots of folks also actually liked the look of the LaScala bottom end better than the look of the Belles.

Now lets look at the bass bin resonance problem of the LaScala, which is primarily in the front edges of the sides, which causes drops in perforance in the 200-300Hz range. How can we solve that? Pwk just took a stock lascala and added braces between the sides and the doghouse, which worked but was not feasible for production models due to the need for custom fitting of the braces. I can NOT claim credit for the decision to go with 1" sides of the LaScala II, even though I did make a point ON THIS FORUM almost two years before the LaScala II prototypes were built that thicker material on the sides could likely solve the problem without having to use braces.

OK, let's look at the company stance on this issue. Not selling many Belles. Belles are a much more labor intensive build than LaScalas, they require a separate crossover designed specifically for them, they require a separate packaging system specificallyy for them, they require a separate mid horn lens specifically for them. LaScalas do not command nearly as high a price because they do not have fancy veneers on them, plus LaScalas have a resonance problem in the bass bin sides that Belles don't have. So, how can the company do away with some of this excess expense and increase profit margins? Simple: Come out with a LaScala that looks like a Belle, a bit cheaper than the Belle, using the standard LaScala components but with its side resonance problems solved by using thicker construction material. The bonus being that they will ALL be made as home speakers, which means customers must pay more now for a fancy veneered LaScala.

There you have it...one expensive speaker replaces two models, one of which was more popular but less expensive, with the added benefit of eliminating most of the resonance problems in the formerly less expesive speaker.

How do you market it? New Improved LaScala, now a beautiful home speaker, with grill cloth and all! A better match as a center channel for Klipschorns than Belles were because its top end is voiced the same as that of the K-horns.

So, why is MDF used in LaScalas now?? Simply because all veneered speakers in the heritage line use MDF (plus it is still cheaper than plywood, hint, hint!).

Any questions??

BTW...Use of K43's instead of K33's in original style LaScalas has NOTHING to do with improving the 200-300Hz resonance problem, since it was a cabinet structural problem and NOT a component problem. Actually, the K33 is a better choice for LaScalas that are not tending to be overdriven!

[ClaudeJ1]

You confuse the heck out of me. You insist on K33's in your MWM's but put K43's in LS for home use.....

It's called measuring and listening to lots of the same reference recordings over a year. Plus former Klipsch Chief Engineer Gary Gaillum, woho worked with PWK on the project and whose name is on the 1980 MWM patent, told me the K-33's were the woofer that the MWM's were built around. I came to the same conclusion even before I talked to him.

I was surprised and amazed at the superior upper midbass and midrange performance of a K-43 in a LaScala. IndyKlispchFan has all K-43's in his 7 LaScala bass bins for his HT. I'm sure they make a major contribution to his terrific HT setup, but you gotta get blow 100 Hz. with subs when you use K-43's in a LaScala. Remember, Mike, I use my MWMs for stereo and RL channels for HT, NOT for P.A. I'm sure I would switch to K-43's for PA use, if required by the venue.

Roy Delgado told me that the higher BL product in the K-43 tilts the response towards the higher enc while the K-33 tips at the lower end. This has been confirmed by my measurements and listening. Much better guitar, piano, vocals etc. on the K-43 in the LS bass bins, but it really thins out the low end.

The K-43's in the MWM were an afterthought because they were frying K-33's in a PA system.

[kg4guy]

Thank you HDBRbuilder that was my general thinking and thank you for taking the time to post it in detail.

[ClaudeJ1]

Now lets look at the bass bin resonance problem of the LaScala, which is primarily in the front edges of the sides, which causes drops in perforance in the 200-300Hz range. How can we solve that?

You forgot to mention the 150 Hz. peak in ALL LaScala bins, the I ended up filtering out with a Digital Active Xover, but even if I had LaScala II's, I'd still use K-43's in them for a much crisper definition on piano, vocals, sax, you name it.

Or, do like I did, get old Peavy FH-1 or SP-1 bass bins and put Klipsch woofers in them. The bracing is built in, the cab is wider, etc. When I put K-33's in mine and filtered out the hump at 180 Hz. those suckers went down to 30 Hz. in a small room, verified by instruments.

But, there is absolutely nothing that touches even plain vanilla LaScalas with K-43's and an MWM bass bin underneath to pick up the last 2 octaves kick bass *** on everything, and raise the tweeter to perfect ear level.

[HDBRbuilder]

Claude, did Gary Gillum (who was never "chief engineer" at Klipsch, but WAS PWK's CHIEF ASSISTANT for a time...PWK was chief engineer and chairman of the board...Gary was a science teacher before coming to Klipsch) ever tell you that the MWM was a rehash of the RCA theater speaker PWK had him drag out of the Hope theater before it was torn down?? Of course the MWM was originally built around the K33, since that was the only 15 inch woofer being used by Klipsch at the time! You may not know it, but I worked there when all of this was being done, so you don't have to explain who was what and so forth to me, because I was there. I likely also built the MWM's you have in those pics, since that was one of my building responsibilites at the time. The fact is, the number of folks who can throw a split mwm under their LaScalas in a home listening environment are few and far between so that is a moot point for the majority of LaScala owners, agreed?? So let's look at the K43 deal...if you are pushing more than 105 wpc into LaScalas, use the K43, for its greater power handling capabilities, that's all.

I can take a pallet or two of K33's, and same for K43's and test them in LaScala bass bins, and find just as many K33's as K43s, if not more, that do what I want them to do. Standard testing parameters only validate meeting of minimum requirements to be used in production, whereas complete testing can produce ideally-matched pairs which may well exceed minimum requirements for production use, agreed?? So, emphatically stating that it is the K43 that meets your performance curve parameter while the K33 does not is a relative statement, agreed??

IOW...can you honestly tell me that I could never find a k33 and a k43 which both had the exact same performance characteristics and curves when used in the same LaScala cabinet??

Just like...the 1973 Ducati Imola SS 750 was track tested at the factory to ensure it would go 210 km per hour, otherwise it never left the factory until it could do so. Does that mean that NONE of the 1973 Ducati Imola SS 750 bikes left the factory capable of doing 220 km per hour on that test track?? Of course not!! Think about it

[bodcaw boy]

IOW...can you honestly tell me that I could never find a k33 and a k43 which both had the exact same performance characteristics and curves when used in the same LaScala cabinet??

that would indicated bad, real bad qc on the woofers.

roy

[bodcaw boy]

I can NOT claim credit for the decision to go with 1" sides of the LaScala II, even though I did make a point ON THIS FORUM almost two years before the LaScala II prototypes were built that thicker material on the sides could likely solve the problem without having to use braces.

after two years of coming to work at klipsch in 1986 i made the same conclusion.

roy

[Guest " "]

" MDF vs. Plywood for La scalas"

seperate from the improve sound of the LaScala II's due to using the AL-4 xover which is also used in post 2003 LaScala 1's, if I were going to paint a set of LaScala's I'd rather paint ply than MDF. The MDF Klipsch use's looks like compressed layers of cardboard once it blows up after a mild impact.. Once the MDF gets damaged, you have issues...if you have egde damage..it cant be repaired...for example...a chiped off corner...try bondo'ing some mdf and you will see what I mean.

a top section which arrived with a 2" section of edge damage cost me 300+ to replace. If it were ply, I could have drilled dowels into it, built it up, and blended it pretty easily.

[colterphoto1]

I think one issue that folks might have with adding the braces is trying to fabricate a means of attachment that doesn't pierce the outer birch skin or call for a separate cleat nailed to the inside of the horn mouth.

Roy or Andy, do you think that the addition of the fibreglass mat and aluminum trim give substantially more stiffness to the LSI cabinets?

Roy, can you give some data from the LF measurements of LS v LSII bass bins? Is low frequency cutoff F3 or F10 lowered?

And always remember gang "A K43 woofer will successfully protect a 4 amp fuse" - Jim Hunter

So PLEASE check your fuses in pro gear. They left the factory with 20 amp fuses. So far I've bought about 40 Pro cabinets and nearly every one had blown drivers and 20 amp fuses. arrrggghhh MWM bins erroneously state to use 5 amp fuses on the jack input cup. (not a complaint to the factory, just that users didn't read the friggin manual or service bulletins)