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cradeldorf

Modified LaScala Horn question

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Today I decided to play around a bit, still him hawing around ideas. Came up with this design still needs refining IMHO but a start.

post-57173-0-45600000-1436062869_thumb.j

Edited by cradeldorf

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I measured the response of a driver with a theoretical mass roll off in the 150 Hz range in horn "kuben" quite similar to LS. It worked well up to 1200 Hz at least level vise! I assume that the mass roll off stipulates that the cone works as a rigid piston and cone breakup alters the response.

One way to get the LS to go a bit deeper would be to have an additional horn section extending 20-30 cm into the doghouse. Byusing two 10" driver per cabinet as drivers they would fit in a narrower part of the doghouse.

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"Came up with this design still needs refining IMHO but a start."

 

The LB-76 barely makes it to 400hz, see the patent.

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I scrapped the upright idea and worked on the LaScala design some more over the weekend. Just mulling over actually building them as I already have 2 pairs of speakers in my cramped house that don't sound all that bad. But I'm jonesing for a project....

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why don't you research in the archives here on the University "Classic" and the corner version the "Dean". This is a substantial horn with minimum folds and maximum extension and can be used to build a true two way system. One of our members Nico Boom has two sets of Khorns and a set of Classics and he said while the Khorns shake the walls of the house the University shake the concrete slab floor, Nico has both sets of Khorns in storage. there is much interest in this truly wonderful design and it is a simple build. Good luck have fun what every you build. Never a bad idea to have a true classic in your system as a reference standard for your own projects to compare to. These are close to Khorn size. Best regards Moray James.

PS: here is another very fine looking design which like the University has limited folds and very good response but which is a little larger could be positioned in the horizontal or vertical position.

http://www.egbeck.de/expo15.htm

EG Beck Tractrix 15.htm

Edited by moray james
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why don't you research in the archives here on the University "Classic" and the corner version the "Dean". This is a substantial horn with minimum folds and maximum extension and can be used to build a true two way system. One of our members Nico Boom has two sets of Khorns and a set of Classics and he said while the Khorns shake the walls of the house the University shake the concrete slab floor, Nico has both sets of Khorns in storage. there is much interest in this truly wonderful design and it is a simple build. Good luck have fun what every you build. Never a bad idea to have a true classic in your system as a reference standard for your own projects to compare to. These are close to Khorn size. Best regards Moray James.

PS: here is another very fine looking design which like the University has limited folds and very good response but which is a little larger could be positioned in the horizontal or vertical position.

http://www.egbeck.de/expo15.htm

Thanks for the heads up Moray. I'll post my latest drawing later today. :)

Edited by cradeldorf

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Here's what I came up with. It's 31" wide 24" deep and 19.5 high. If I taper the top and bottom from the throat to the mouth and I taper the top and bottom of the doghouse from the driver to the port there should be zero parallel surfaces in this design all while maintaining a constant expansion of the horn.

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Edited by cradeldorf

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For the size you may just as well build a Peavey FH1 with an extra brace Same size and performance which is going to be as good as is possible in this size Better than a Lascala better than a Belle but none of these is going to get you very low. The Peavey will get you up to 400 Hz The Beck or the University Classic/Dean will get you higher than that. What is it that you want to achieve for your design goal? Once you have your goals in place it becomes a lot easier to identify what will or will not get you to where you want to go. The Caire designs are solid quality designs which represent the best possible compromise for their bulk in a simple folded horn with guaranteed results. Much effort and time went into these designs and the likelihood of a first off prototype getting close to these in terms of performance is very small. Straight horns will work better but are big horns like the MWM or Claude's 1/4pie are also worth while compromises. You can run a single wide band 8 inch driver from 2 - 300Hz. up to 18KHz. Rudy is doing this and has had fantastic results. Lots of options just depends upon what you want to do. I have also attaches the design for the Beck "California" which while large has the widest response and the greatest output in a simple build not too much larger than what has been discussed here. Best regards Moray James.

bt02.pdf

bt01.pdf

Ernst Beck California bass horn English text.htm

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Edited by moray james
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. What is it that you want to achieve for your design goal?

A perfect sounding 2 way horn loaded setup that can do crystal clear sound up to122 db continuously. Able to shake the drywall off the ceiling when the movie calls for it. able to break glass when Robert plant hits the high notes. Able to turn me into a Unich When Steve Perry sings.....  You know ... The usual... :)

 

Oh yeah perfect point source too. I was considering the great plains 604's but at $950 a piece.... not really what I wanted to spend... Woof.

 

What are your thoughts about porting the doghouse? I notice that I keep mentioning it and you keep posting designs that are not ported? Do you think porting it is a bad idea? I was under the assumption that porting it would allow it to play lower although I have no idea how much lower it would go? Also do you think lowering the compression ratio (Larger throat) would be a good thing? I'm picturing the Altec A7's with their front loaded horn and BR cabinet behind the driver. Their throat is much larger than the LaScala's...? would a Larger throat give me more bandwidth but less loudness?

 

Somehow I'm picturing those designs more as TQWT or Transmission lines than horns as most of their area's only consist of one tapered side or parallel rectagular tubes?.... where a true horn would have all sides tapered at all times.?

Edited by cradeldorf

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it sounds like you habe a plan so why not buy a beater set of LaScala and knock up a riser mod with vents and see what you think. Of the three speakers LaScala Belle and FH1 the FH1 is the largest and it edges out the other two with none of their problems You can port any of them if that is what you want to do. The riser mod should get you usable bass into the upper 30 Hz range. The throat size of the LaScala is perfect if you make it larger or smaller you will diminish the performance. These speakers are limited by their length and mouth size that's it. If you want lower extension then you need a longer horn and a larger mouth. You cannot compare an A7 with a LaScala. If you want more then something like one of the Beck designs or the University horns ought to get you where you want to go. As I suggested before look into the Azure style horns there are a number of them available. I can't tell what it is that you want but you can look and listen and eliminate what you don't like or want and that will help you to figure out what you do want. What you seem to be asking for won't come cheap and it won't come tiny. You will have to fill in the blanks for yourself.

How about a pair of these?

KPT-942/4-B THX®

Item #664 | Available at your Local Dealer.

DESCRIPTION

The THX®-Certified KPT-942/4-B two-way screen and stage loudspeaker system is based on our new KPT-415-LF quad 15-inch bass unit providing enhanced bass output while retaining the 24-inch depth of our smaller systems. Higher frequencies are handled by a KPT-402-HF Tractrix® Horn with a K-1132 two-inch exit titanium compression driver.

http://images.klipsch.com/KPT_942-4-T_-_Angled_635284150756767000_medium.jpg

The KPT-942/4-B's high efficiency very high output and excellent coverage characteristics make it an outstanding cost-effective solution for medium and large auditoriums.

Quad 15-inch bass unit Tractrix® Horn with a two-inch exit titanium compression driver

24-inch depth

Bi-amp configuration

SPECS

Frequency Response: 43Hz-18kHz 3 dB, -10dB @ 26Hz

SENSITIVITY: 107dB

POWER HANDLING: 850 watts

SYSTEM COMPONENTS: LF - KPT-415-LF 400 watts

HF - KPT-402-HF 50 watts

CROSSOVER FREQUENCY: 500Hz

CROSSOVER SLOPE: 24dB/Octave

COVERAGE ANGLE: HORIZONTAL 90 30 200Hz-14kHz

VERTICAL 60 30 300Hz-18kHz

DELAY: LF- 0.1ms

MF- 0ms

HEIGHT: 76" (193.04 cm)

WIDTH: 39.75" (100.97 cm)

DEPTH: 23.75" (60.3cm)

WEIGHT: 260 lbs. (118.0kg)

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Hah!!! I was just drooling over those KPT-942/4-B THX® Last night, Yep that's the type of performance I want right there, LOL I'm betting they're a few bucks more than I have to spend though. 

Oh yeah I may have forgot to mention I need to stay pretty much below 45" tall.... otherwise I can't see over them to my wall where the picture is playing. :( That 402 sure is a work of art though. :)

 

considering the dayton woofers are 80 bucks a piece I will probably just toss together a set of my design and give em a whirl. one of my goals is to try a design with absolutely zero parallel surfaces just to see if my hunch is correct. and I could always block off my port to see if it sounds better or worse. I think I'll still come in under what a pair of beater LaScala's would run me even if I ever stumbled across a pair. what really sucks is we have a pair here at work that have been lying around unused for almost 10 years. some industial ones. :(

Edited by cradeldorf

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Used 402's??? is there such a thing? I would think they are hotter than hotcakes?

I've seen those cabinets before, Aren't they called "W" cabinets?

Edited by cradeldorf

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Google Alerts will notify you immediately when listings are posted. Claude bought his used and there have been a good number sold on this forum over the last number of years. You could start with K510 with the same drivers and wait for a set of K402 to show up or you could drink less beer and save the money to buy a set of horns new. Works for most people.

Here is a thread about Claude's old rig

https://community.klipsch.com/index.php?/topic/149887-fs-peavey-fh-1-bass-binseminence-15c-woofers/

Here is a set of plans for a Peavy FH2

http://hornplans.free.fr/fh2.html

https://community.klipsch.com/index.php?/topic/142048-oris-150s-have-arrived/

Edited by moray james

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http://www.diyaudio.com/forums/subwoofers/268959-zobsky-contemplates-variation-belle-klipsch.html

The logical extension of the Belle is the Peavey FH1 if you are looking for the longest horn path and the largest mouth. The difference is not great but you do what you can to stretch them out and the FH1 is where you end up. The FH2 is also interesting.

post-44375-0-18540000-1436886603.png

Edited by moray james
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I actually came up with a different path to go down, just him hawing over driver choice. Most will cringe at it, but I like trying things for fun. I posted it over on the DIY site since it's not really Klpsch in any way.

 

http://www.diyaudio.com/forums/multi-way/277073-input-wanted.html

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Edited by cradeldorf

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ok but don't say I never gave you any info on a design with a vented dog house. Have some summer fun and remember that anything that does not work out you can use for a late night bonfire.

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ok but don't say I never gave you any info on a design with a vented dog house. Have some summer fun and remember that anything that does not work out you can use for a late night bonfire.

Thanks Moray, I had a 3 pairs fire last year.... :D

Edited by cradeldorf

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