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ngccglp
09-01-2006, 06:18 PM
Hi,

Recently I experienced the high impact sound of the Klipsch La Scala, although overall I wouldn't rate it better than my Altec A7, but I am attracted by the slam of the bass horn.

Which prompted this posting. I was thinking of making the bass horn of the La Scala but using Altec 416 as the woofer. Alternatively I could order the Klipsch woofer which is not very costly. The horn will be the 511B/802.

Need advice on whether my experiment will work.

Thanks.
speakerdave
09-01-2006, 08:15 PM
What is the crossover frequency of the La Scala? I doubt that the 511B will reach down to it. I don't think you can successfully play a front-loaded folded woofer horn up to 500 Hz.

David
norealtalent
09-01-2006, 08:22 PM
http://www.lansingheritage.org/images/jbl/catalogs/1974-pro/page09.jpg
ngccglp
09-01-2006, 11:26 PM
Is there a formula to calculate the dimensions for folded horn? Also the la scala seems to be firing backwards, and looking at the design, seems like an infinite baffle design behind the driver.
Tom Brennan
09-02-2006, 07:12 AM
I've been told the LaSlala horn, unlike the big Khorn which has one more fold, extends up past 500hz.

I used similar Peavey FH-1 basshorns with 511bs and various drivers (Altec 802s and 902s and JBL 2420s) with no obvious problems. The Peavey horn uses reflectors in the corners, those may help with getting the mids around the bends. In any event my RTA showed no problem in the 400-500 cycles range.

I also measured the FH-1s as flat down to 30 cycles which amazed me, then I turned the furnace off. ;-)
Titanium Dome
09-02-2006, 08:03 AM
then I turned the furnace off. ;-)

:rotfl:
speakerdave
09-02-2006, 10:08 AM
http://www.lansingheritage.org/images/jbl/catalogs/1974-pro/page09.jpg

NO REAL TALENT's heading "I think they will"

Those information sheets about JBL scoop bins (these horns load the woofer at its back) use the phrase "front-loading" with a different meaning. They mean you put the woofer in the hole from the front of the baffle.

Notice, my original post said " front-loaded folded woofer horn."

Me, I was referring to the matter of placing the horn in front of the woofer and putting some bends in it.

Anyway, apparently the La Scala woofer section does go high enough for some, but Klipsch crosses over the La Scala at 400 Hz. Even that is a stretch, I think.

David
Tom Brennan
09-02-2006, 10:47 AM
" Klipsch crosses over the La Scala at 400 Hz. Even that is a stretch, I think."


A pal, a retired WE engineer, has measured LaScala bassbin response as strong at 600hz. As for ole PWK crossing at 400, well why not? The stuff to do it was, as he used to say, "available". ;)
speakerdave
09-02-2006, 04:45 PM
. . . . As for ole PWK crossing at 400, well why not? The stuff to do it was, as he used to say, "available". ;)

I don't know a lot about Paul Klipsch, but I have heard that he cultivated an idiosyncratic folksy persona. He was also known for his shrewdness, and I doubt that he made any design decisions for such a reason solely.

David
Tom Brennan
09-02-2006, 06:25 PM
David---A good friend of mine was a friend of PWK and he assures me that he often made decisions based on what was available and at a good cost. Much of PWK's talent was in making collections of very average parts into outstanding systems.

How many guys here are interested in stamped frame CTS woofers, Atlas bullhorn drivers and T-35 tweeters? Not many I'd guess. Yet PWK could make that stuff work very well.

Regards
speakerdave
09-02-2006, 08:39 PM
David---A good friend of mine was a friend of PWK and he assures me that he often made decisions based on what was available and at a good cost. Much of PWK's talent was in making collections of very average parts into outstanding systems.

How many guys here are interested in stamped frame CTS woofers, Atlas bullhorn drivers and T-35 tweeters? Not many I'd guess. Yet PWK could make that stuff work very well.

Regards

Well, there certainly seems to be a lot of chitchat about figuring out how to make them sound better. I don't think I've ever seen a query about putting a Klipsch horn and driver into an Altec or JBL speaker. Admittedly we talk about updating crossovers and about the possible improvements to be found in more modern drivers. And we've had the experience of the speaker's designer posting here and frankly discussing a speaker's shortcomings and how they can be improved. After all, most products are made to a price point. One advantage of the inexpensive components Klipsch used is that collectors who appreciate the fit and finish of fine drivers are not driving up the price.

David
Maron Horonzakz
09-03-2006, 10:05 AM
Not so fast day old bread breath.....Ive seen a Hartsfield with a Klipsch 400 mid horn & driver. No serpentine lens as achoustical filter.:D Not bad sounding.
speakerdave
09-03-2006, 10:32 AM
Not so fast day old bread breath. . . .

Corn rye if you have it.
Maron Horonzakz
09-03-2006, 10:48 AM
Not to get off subject....Take a slice of good rye bread. Butter it good. Then dip in a cup of coffee. It,l put the hair back on your chest.
speakerdave
09-03-2006, 11:03 AM
Not to get off subject....Take a slice of good rye bread. Butter it good. Then dip in a cup of coffee. It,l put the hair back on your chest.
Coals to Newcastle, thank you.
Hoerninger
09-03-2006, 12:45 PM
@ ngccglp (http://audioheritage.org/vbulletin/member.php?u=610)

The T/S parameter I found in WWW showed me a low moving mass so it should really work up to 500 Hz in a front loaded horn. I've simulated the LaScala with Hornresp and it gave a good result.
____________
Peter

PS: The spacings are about 7,5 cm, that's 1/10th of the wavelegth at 500 Hz, so the waves should come around.