Project Lilscala

[Guest " "]

GotHover

Did you use tuned ports or just seal the top and connect the upper chamber to the lower?

I don't favor one over the other, I'm just curious what your final config was.

[LARRY]

GotHover,

Very nice cabinets and interesting project. Note the Heresy has an internal volume of less than 1.9 Cubic feet, not allowing for the woofer displacement. Even though a 12 inch woofer is about 20 % less than a 15 inch woofer, the actual surface area is only about 60 % of a 15 inch woofer. I know very little about horn theory and am only pointing this out so that those who 'know' can comment. I am interested, as I would like to scale down a Belle for my center channel. Please keep us advised of your progress.

Larry

[Guest David H]

Did you use tuned ports or just seal the top and connect the upper chamber to the lower?

I simply sealed the upper chamber and ported throught the separater plate, using the previously cut 4"x 4" opening I had cut in the bottom of the upper section to access the woofer terminal strip, You can see the opening in the previous post where I show the back open.

[Guest " "]

GotHover

</p> OK, got it , I saw that. So what's next, mini Khorns and a mini belle so you can have surround sound?

[Guest David H]

So what's next, mini Khorns and a mini belle so you can have surround sound?

Don't think so, I dont even have room for the Mini's I built, it just seemed like a fun project. Project Lilscala was well worth it, because I have learned so much about horn design and wood-working, this is my first speaker project, not including making sub boxes for my car and house.

[Guest David H]

Latest update project Liscala, After porting the bass chamber into the tops of the box for added volume, I needed to pull an put many times ie. xovers badding etc, while doing this I had the speakers playing, and I noticed when I pulled the front upper motor board forward to acces the box internals, the speaker sounded excellent. so I did some measurements and found my bass at 50hz is now down 4db from 80hz, however my sound gap from 500-700 seemed to be filled, I suspect this is because the folded horn can no longer dictate freq response through a port. Next, I removed the backs from the box and installed a 4x4x4" round pvc port then reassembled to retest. With the rear ports installed I once again had to move the tweet and squalker up on the autoformer and the sound is excellent. I no longer notice a gap in the sound, I feel the transition from the woofer to the mid is very smooth. (Or I am just too tired to know the difference)

I am sure there is a hundered good explanations why I should not port a folded horn, And I only have 1 good reason for doing it. "Its all about the sound."

[Guest " "]

"I am sure there is a hundered good explanations why I should not port a folded horn,
"

</P> your not alone on this, a few folks have ported normal LaScala's in the same manner. Some did it as you did, others added a box underneath with ports facing the front.

[jwc]

I'm not a professional. A hacker. I'm glad someone has posted a DIY bass horn project. I would love to see more people do this.

I lost the original post that had some stuff and haven’t been able to get back to the forum until now.

I want to start by saying…what an awesome job you have done on these Lilscalas. Not just because they look good….but for other reasons. I think you have officially coined the name.

You welcomed input and were able to talently go back and make a change to make you design work. W/O the ramps…you really didn’t have a horn.

Now I had requested some information from you so that I may be able to backwards calculate your horn.

Now…..I believe you stated that the length of the horn was about 29.25 inches or 74.3 cm. Now there is non expanding portions of that kinda horn design so really the horn isn’t that long. But….for argument sake…lets say it is about that long.

W/O the port mod, the woofer chamber was 1.3 cu ft.

Now forget the port mod for now and assume you didn’t put it there.

The mouth is about 361 sq in

Your throat is about 52.5 sq in. Now…the slot is 26.25 inches….but…that goes back to the “throat riddle” of PWK. Just like the La scala slot is 3 x 13 but the throat is 78 sq in.

Anyway……I’m impressed to say the least. I know there wasn’t much calclution in your design but more of a “scaling” down.

Cool enough, here is what I come up with.

The K22 in a horn in 1.3 cu ft annulls at 70Hz

If assuming an exponential expansion, and placing this horn in a corner (1/8^th space), you have yourself an almost full length 1/8 space 70Hz horn. Now I know that the rules of 70Hz constant exponential expansion did not occur throughout the horn….but then again…neither did PWK.

So….In a corner and looking at this from a positive note for the corner….assuming an 8^th space horn……cool job.

Now. The horn really isn’t 29.25” as I said above. It is really shorter. The expansion would also not follow a 1/8 space 70Hz horn…..but closer to a 100Hz ¼ space horn. Also your internal volume is 1.3 cubic feet but the volume subtraction of the K22 bring the volume to about .9 Cu ft. Guess what, the K22 will annull at about 100Hz in 0.9 cu ft chamber.

So there you have it….my non professional calculation of what you made.

Now….you have a port in there and expanded the chamber volume. I can’t predict that result on paper. Dr. Who could probably help with what to expect with that.

If someone wants to build another Lilscala…Marshall….I would do the throat/slot differently. Esp if harvesting Heresy parts….such as using the K700. There is way to “calclulate” the appropriate throat size for “midband efficiency”. Also…I would add reflectors at the last turn. That way….the bass bin might make it out close to 700Hz. However, I can’t predict “beaminess” or polars.

Dman! If you are reading this……….please come make a rebuttal of my comments!

jc

[Guest " "]

JC

Belle style cab with reflectors might make it to 700hz.

[jwc]

JC

Belle style cab with reflectors might make it to 700hz.

Yes that would be nice. Everyone has different goals in mind but I would be interested in something like that w/o the intention of going real low in Hz. I would rather have a non ported horn.

Now the innner chamber volume would be a little big (inless you put two K31's in there...that volume works out pretty good).

I would do close to 5" W x 9"H slot. The height would depend on what I wanted the fnal slot size area to be. In any case, the "Ramps expansion area" would be 2.5 inches in width and the Width of the horn right after the last turn would be 2.5". That way you can have a full 45 degeree reflector. The right throat size and reflector might get you out to 700Hz nicley.

Of course...we can change woofers.....That is what I would do. But this thread is for heresy parts.

jc

[Marvel]

In any case, the "Ramps expansion area" would be 2.5 inches in width and the Width of the horn right after the last turn would be 2.5". That way you can

jc

jc, if you do that with the reflector, you only have about a 1.75 inch opening on the turn. It might still work out ok. Dennis had orginally posted this when he worked out the mod for the ls: "The taper rate of a LaScala is 100hz,The mouth area is good for 125hz. Below this it is a big woofer in a small sealed box."

This makes me think that, in some respects, you can't think of it as a horn below a certain frequency. Gorgeous little cabinets, though.

btw, the BBX is great. Been enjoying it a lot, once I replaced the microphonic 6299.

Bruce

[jwc]

Yes Marvel..that is how the full reflector is supposed to work. Bruce Edgar described how this works in the "show horn" and the "monolith".

Yes PWK...was able to get the La scala down in the 50Hz range even thought the expansion rate of the last flare is 125Hz. Good isn't he.

Glad you like the BBX. I have a Peach now to use Bypass if needed. I might change the tubes too.

jc

[jwc]

I always wondered what a LiL" Cornscala would sound like? Very nice work, however...

BS

Hey Mississippi dude.......

I thought I did that one....Herescala

http://forums.klipsch.com/forums/t/62576.aspx

jc

[jwc]

w/o the grill.

[nomad02rider]

This project has made me think about a Baby Belle for center channel duty or even building a big screen tv center channel stand/speaker combo. Nice job!

[Guest David H]

Thanks for all the greats comments and info, although half the time I have no clue what you are talking about, I still appreciate the info.

Today the Lilscala's went on their first field trip, to visit and a/b with the original Lascala.

[Guest David H]

Initially we installed the Lilscala to become acustomed to the sound. The system used for testing consists of an Onix SP3, Sony ES CD changer, and a Pioneer Elite Processor. The Beringer feedback destroyer is used for bass management, but was turned off for the heads up testing. The Lascala's in the pics have updated AA crossovers K77 Alinco K55 and k33 all O/E. The Bass bin mod has been done to eliminate doubling. Initial impression was the Lilscala is a tad bright, but when I checked I found the processor was set to +4d on treble an the bass was flat, once I returned the treble to flat, the overly bright issue was solved, I suspect my new Crites CT125 tweeter outperform the 20+ year old k77. On with the test, to make a long story short, Myself, Craig, and Paul were in shock as to how good these sound. To quote Paul "These things dont miss a beat" We used a variety of music for testing, to list a few Kraftwerk, Norah Jones, Supertramp, Pink Floyd, Depeche Mode, Diana Krall, Cars, etc. Overall they sound right.

[Guest David H]

Next we performed some primitive A/B testing, processor set to mono, Lascala-right Lilscala-left, the chosen music Nora Jones "Come Away With Me" The first couple seconds of the song the speakers were indistinguishable from each other, as the song progressed Nora's incredible voice sounded smoother and a slightly louder from the Lascala's K400. The bass was a similar as well as spl. As for the top end, the CT125 definately outperformed the K77, I suspect BEC will be selling another set in the near future. Overall the O/E Lascala outperformed the Lilscala in midrange perfomance (DUH) but I am tickled how well these little guys held their own. In the past I compared the performance of the Donor Heresy's to these Lascala's when they were previously owned by Craig the other listener for todays test, and there was no comparison.

In the long run I think the Lilscala may benefit from the K600 horn lenses and k55 driver VS my K700 paired with the K52H.

But this project was to better the performance of the Heresy internals in a miniature Lascala enclosure........Acheived Yeah.....

I had no idea that Project Lilscala would be this involved, and I could not have pulled it off without the help and knowlege of the klipsch forum members. Thank you all for your help and support. FYI I was ready to give up on the project in the testing phase because the sound was not right.

[Guest " "]

Love the field trip report.

A/B'ing Heresy's to LaScala's would not even be close so it's interesting what a new set of cloth's will do for the Heresy.

[BS Button]

Almost furgot that one. They are still all "Children of the Corn"...