Bubo

Dumb question. The K-33 circa 1980 LaScala bass bin puts out 105 db @ 1 W 1 M?

They both do. But the Peavey is smoother. Do you have the Peavey response curve, can you post it??

I thought some tube response curves might help illuminate the hump issue. Not. The magazine test is interesting, the manufacturers response is scorching or worse. http://www.stereophile.com/content/dynaco-stereo-70-ii-power-amplifier-measurements http://www.stereophile.com/content/dynaco-stereo-70-ii-power-amplifier-manufacturers-comment

This has probably been discussed many times, but I'll ask the question. There is clearly a performance curve in the LaScala woofer section that is more efficient at the hump that Claude plotted for us. The question then becomes, is the hump the result of the K-33 design, or the the Horn design, or both? IMHO trying to fix it after it occurs, is always a bad engineering solution and probably the reason some crossovers are not well received, like patching the outside of a tire. If the Hump is noticeable, and undesirable, I would think it would be better to attenuate it in an EQ before it reaches the Amplifier and Crossover. Without Klipsch's Engineer notes, if they exist, it's hard to know what his intentions were. The hump may have helped to sell speakers, or even been a compensation for the tube amplifiers of the day or the way sound travels in auditoriums, churches and theaters aka he did it for a reason. Like so many good things, Moray surfaced this article on a different thread. I doubt if Klipsch gave everything away in an industry paper, but enough to make it interesting, and help sales. I assume the Industry Theater Speaker he is comparing to is the Altec A-7 2-Way, drivers unknown at this minute. Does a 2 in driver in a 2-way speaker extend the highs in a flatter response than the A-7 high end did? Or the Altec 802- pick your letter D G etc..... There is also the question of which Altec Horn Klipsch was comparing to, 811, 511 or something else, but ringing is a common complaint with these two. Then there is the question of which horn sounds the most lifelike with female voice, the K-55V is so sweet it sets a high mark for comparison. LaScala AES Pre-print.pdf

If you can scan the paper copies and post them as a high res PDF that would be best, if it's just the Gif files, post them.

I started having flashbacks from re-doing my upstairs bathroom 20 years ago........

Horns I can't find on LaScalas Auto Tech makes these, don't know anything about them. DIY 'Sound Group sells these SEOS and IWATA and Auto Tech Auto Tech Iwata Horn 2 variations, I have seen this mounted on A-7 Bins Link to A-7 Pic

Do you have the top panel above your mid horn? I am curious to see if any of the high frequency program is lost behind the baffle when seated. How far from the front of the baffle is your tweeter? A possible simple test is tape a piece of string halfway inside the horn lens, and pull it snug to see if it clears the baffle without bending. "The higher frequency sound waves have a shorter wavelength and thus don't spread out as rapidly. For this reason, the resulting directivity of these devices is far higher than physically possible with any loudspeaker system." https://en.wikipedia.org/wiki/Directional_sound If we are going to be moving the tweeters way back to align with the mid drivers, should we get longer lenses to control the diffraction so we are not hitting the tops of the cabinets?? Lenses also have their own baggage and reflections may become and issue with other effects.

Like so many good ideas, Moray also surfaced this one. Paper Horns http://www.inlowsound.com/

If the receiver has pre-outs for the (5+).1 channels and the sound quality is good, I don't see any reason to not use one. There also are Pre/Pros out there too that are refurbished for about half their sticker price that work extremely well. It's an economic decision. The base version of Audyssey that ships with receivers and pre/pros isn't, IMO, good enough to do any customizing or to even see even what it is doing. I recommend another brand of automatic room EQ, or if you have the money, the "pro" version of Audyssey works for the few guys that have sprung for the additional $500+ for that firmware version over the base version. That seems like a lot of money, though. That would be a good choice if the power amplifiers have good sound quality. That can save a lot of money over separate EQ units, external amplifiers, and associated cables. Chris As an experiment, I set up a surround system that literally sits on top of my LaScalas (if I had a bigger room, or house, it would have been 5.2 with Heresys and LaScalas I have the gear) using the Synergy TOTL small B3 as fronts C3 and S3 speakers with 3 excellent Yamaha MX 800s fed by a Pioneer Elite THX Surround Pre Outs with the Center channel Bi Amped. It sounds surprisingly good. In this case the Amps outclass the speakers and probably pull them up a bit. My 1980 Mac Gear has been with me so long that it's hard to connect anything else to the LaScalas, though I did rotate 5 amps one time when the Mac was in the shop, all sounded good, the Yamaha was the best. If I ever get more room a third rack with a circuit switch or patch panel will be set up.......... BTW does everyone OEM Audyessy or are there other vendors out there. Emotive uses something different in their new TOTL. Thanks, Mark

Chris, Thanks, this brings me to the next question which is how do we adjust for the gear and the room, which is going active. The cheap and easy fix is using something like a Pioneer Elite MACC which EQs and does Phase Adjustments, the various high end Surround Receiver Manufactures all seem to have their own version. McIntosh has their own stand alone unit. So it's running correction over the existing gear and Butterworth Crossover. Unless you are set up for bi-amp. Any thoughts on the effectiveness of just using a surround receiver as the stereo preamp? Some support Bi amping on more than just the Center channel. As to a larger room, and or use with sub woofers, the surround unit does allow for 2.0 just LaScalas, 2.2 LaScalas with subs, and 3.2 LaScalas with subs and perhaps a Heresy in the middle if a blended channel can be derived much like using the Bell between two K-horns. I'm pretty sure I could configure my Pioneer THX Receiver into 3.2 run the MACC and adjust down the volume on the center channel, I would have to play with it.

Did you use speaker design software to model the speakers before the build??

Interesting LaScala hybrid build, I love all of the plots on the Bass Cabinet. It's interesting that he found no real improvement in measured lower frequencies from the vent box but felt that it tightened the bass up a bit, which was a subjective observation. Clearly the guy is a skilled wood worker, I would run out of fingers way before the completion of the project.

http://www.rane.com/note160.html Interesting read, well most of it, and for me it had lots of pictures. http://sound.westhost.com/lr-passive.htm Interesting article from Australia DIY supplier, I'm not smart enough to score it. This is what I gleaned. If you need even distribution of sound at all frequencies over a wide and tall area, you are probably talking active crossover, and the Linkwitz Riley is popular for this application. The goal of this crossover, in addition to uniform sound over a broad area is to be perfectly in phase at the crossover point. If you have a favorite chair, the mid drivers at ear level and speakers angled towards your chair, you are in the sweet spot and passive (affordable and reliable) Butterworth crossovers will work just fine. If you move around the room, there are going to be areas that are not the sweet spot, your guests can sit there. The differences between the two approaches is managing the phase alignment of multiple drivers over the desired area. In phase on the same frequency should have an additive effect aka louder and inverse signals on the same frequency should cancel. The effects in between could be observed with two identical drivers and a test tone and something that would allow you variable time delay on one of the drivers. When one is at zero and the other is at 180 there should be silence. The speed with which one driver rolls off and the other turns on would also have it's own set of effects, and there is the issue of not slamming the next driver with full power all at once. With all designs, there are the objectives which may or may not be realistic, then there is what can be done and the trade offs begin. A lot of the trade offs are explored on the bench aka "how does this sound"? My two cents.....

Interesting discussions on Klipsch K-33 Woofer with specs http://www.diyaudio.com/forums/subwoofers/176729-klipsch-horn-woofer-designs.html https://community.klipsch.com/index.php?/topic/148475-k-33-e-vs-k-33-b-specs-anybody-have-factory-measured-ts-data/page-2 http://forum.poisonnuke.de/index.php?action=ViewThread&TID=2343 Links to DIY Plans for LaScala and some bass talk http://www.diyaudio.com/forums/multi-way/1344-lascala-plans.html http://www.audiofanatic.it/Piani_costruttivi/pic_piani/LaScala/LaScala.html Scroll down to Marvel's post and his Drawing of the LaScala plans A+ https://community.klipsch.com/index.php?/topic/151099-scala-bass-bin-with-curved-sides/ UPDATE: I forgot to mention upgrading to the Klipsch K-43 Woofer, which apparently specs out better than the stock K-33 Actually just google Klipsch LaScala Plans and all kinds of good stuff pops up https://community.klipsch.com/index.php?/topic/156919-la-scala-build/ Scroll down for bass port to Frodi post links http://www.diyaudio.com/forums/multi-way/41648-more-bass-lascalas-2.html Volti Opinion on Crites K-33 replacement http://www.klipschupgrades.com/criteswoofers.shtml Not exactly stock but interesting from above la scala build thread on klipsch community above. The HornResp program is where things like probably take life Thread on building the Mod below https://community.klipsch.com/index.php?/topic/108425-la-scala-bass-reflex-mod/

Thanks Chris A for this link, discussion on the LaScala Bass Horn Geometry and effect. Can extrapolate into time alignment, someone smarter than me can......... anyway. https://community.klipsch.com/index.php?/topic/94238-la-scala-bass-horn-length/ " The La Scala and Belle bass bins are about 36 inches (EDITED) path length from compression slot to the front face of the cabinet, effectively. Also note that any passive or active crossover will insert from 90-360 degrees of phase lag of the lower frequency driver relative to the higher frequency driver (90 degrees per "order" of the filter used: for a fourth order filter, that's 360 degrees lag of the LF driver relative to the HF driver). My working rule of thumb is that the time alignment needs to be within 1/10th of a wavelength (i.e., 36 degrees) of perfectly aligned at the center crossover frequency. For 400 Hz crossover (bass bin to midrange), that's about 3.4 inches maximum misalignment--including crossover phase shift error. For the tweeter-midrange crossover, nominally at 5 kHz, that's about a quarter of an inch, max misalignment, including crossover filter phase shifts. Chris"

What is the efficiency of the LaScala Bass Section (for that matter what is it's Ohm spec). 2-Way Crossover 500 Hz, 8 Ohm Woofer 8ohm + 8 ohm Compression Driver and L-pad connected to Crossover = 8ohm speaker If I recall correctly, Eminence sells a very affordable 2 way Crossover and the L-Pad attenuator. 2) With the LaScala bass bin, as we experiment with horns, can we move the crossover point up to 500 or even 800 without noticeable degradation of the Bass performance and can the woofer handle the added frequencies gracefully aka the voice still sounds like a voice. Nov-3 Updated above after a tutorial on Crossovers. http://www.parts-express.com/eminence-pxb2-500-2-way-speaker-crossover-board-500-hz--290-630 http://www.parts-express.com/pedocs/specs/px-series-crossover-specification-sheet-specifications-44571.pdf http://www.parts-express.com/eminence-px-lpad-crossover-l-pad-attenuator--290-660

When you mentioned a new type of wave guide/horn, it was like the meat truck passing a hungry dog.......I had to chase it......

Interesting Discussion on Different Horns that can be use with the LaScala Bass Bin https://community.klipsch.com/index.php?/topic/160049-diy-la-scala-mid-upgrade-options/?p=1939593 Who can forget the Jube-Scala Volti's 2in wooden horn for the LaScala and a Beyma CP-25 tweeter on top Oris Horn by BD Design? This one comes with it's own video western electric 15A "small" SATO-Horn JBL 2420 https://www.youtube.com/watch?v=AqhS3BA0BYQ la scala with Bass reflex , bms4590 and jabo72 horn With Electro Voice Horn Below is the Eliptrack by Fastlane Audio Altec 511 Horns have some appeal, but lots of complaints about "ringing" this fellow took a novel approach and build boxes around the unit and filled them with sand, according to the author it had very good effect. Cut Sheet Others have tried all kinds of damping materials inc automotive undercoating. Link is to sandbox pic http://www.audiocircle.com/image.php?id=11430 Below is 511b in LaScala Altec 811 & 511 Horns.pdf

I would not have thought that the baffle would make that big of a difference. With a hand on the outer flare of the horn during offending passages there is little to no vibration and no movement, however it would not be difficult to route a few panels to experiment with this. Look at the bottom of page 3: https://community.klipsch.com/index.php?app=core&module=attach&section=attach&attach_id=8074 Also, try moving the K-77 tweeter back to the K-55 midrange compression driver plane and listen again: the soundstage should expand rather dramatically. I recommend either of the two JubScala configurations. There's no comparison using either horn in a two-way with a good 2" compression driver-they will eclipse the stock La Scala 3-way configuration. You'll need EQ for either controlled directivity horn (K-402 or K-510). Chris Chris, On Horn Alignment of the Drivers, given the folded LaScalas Bass horn, should the K-55 and the K-77 Mid point on the Magnets both be moved approximately 12in behind the enclosure. I'm estimating a 4in gap between the doghouse and the rear of the cabinet; plus the distance from the Dog house rear wall to the mid-point on the Woofer magnet? In other words, if the LaScala Bass Bin were unfolded, how long would it be? I'm guessing 12 in. longer than folded. These are measurements I am also interested in. I think this is one of the things JBL got right on their best speakers and on some of the Altecs like the 820 (and VOTT) which IMHO is in the running for the best speaker ever made.

1) Videos on Youtube PVC implementation https://www.youtube.com/watch?v=27teQsB4bSU Very Nice inc 1in measurements https://www.youtube.com/watch?v=Hlf8NwIlQVA Interview with Karlson on Radio https://www.youtube.com/watch?v=AGSqs9zmNO4 2) Patents Karlson open end waveguide Karlson Patents 2816619 http://pdfpiw.uspto.gov/.piw?Docid=02816619&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect2%3DPTO1%2526Sect2%3DHITOFF%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526d%3DPALL%2526S1%3D2816619.PN.%2526OS%3DPN%2F2816619%2526RS%3DPN%2F2816619&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page 2896736 http://pdfpiw.uspto.gov/.piw?Docid=02896736&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect2%3DPTO1%2526Sect2%3DHITOFF%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526d%3DPALL%2526S1%3D2896736.PN.%2526OS%3DPN%2F2896736%2526RS%3DPN%2F2896736&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page 3540544 http://pdfpiw.uspto.gov/.piw?Docid=03540544&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect2%3DPTO1%2526Sect2%3DHITOFF%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r%3D1%2526f%3DG%2526l%3D50%2526d%3DPALL%2526S1%3D3540544.PN.%2526OS%3DPN%2F3540544%2526RS%3DPN%2F3540544&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page This guy is interesting, has a different tapered slot and lists all the patents like his, but not the same inc Karlson Be sure to use the images button on top. http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=4&f=G&l=50&co1=AND&d=PALL&s1=3,540,544&OS=3,540,544&RS=3,540,544 3) Waveguide Patent Dimensional drawing For some reason the forum won't let me link to images in other forums or on the web WTF???? 4) DIY Forum Complete Discussion with Links to source data http://www.diyaudio.com/forums/full-range/256176-what-real-inspiration-behind-karlson-coupler.html http://www.talkbass.com/threads/karlson-speakers.52071/page-2 IG81 Did some build and took some measurements http://www.diyaudio.com/forums/multi-way/3995-karlson-enclosure-12.html freddi Huge Karlson Fan who owns K-Horns interesting write up like Tubes with PVC http://www.diyaudio.com/forums/multi-way/3995-karlson-enclosure-11.html "Transylvania Power Company's "The Tube" slotted waveguide (an adaptation of John Karlson's X15 internal waveguide from the 60's) is probably the best sounding waveguide in its range that I own and that includes DDS Pro90. The Tube can be approximated with a dime's worth of 1" schedule 40 pvc pipe using a Dremel cut wheel and a half ellipse slot. Drivers from B&C, Eminence and Selenium sound fine with this size 1 inch format Karlson waveguide. (BTW, Karlson patented the open end waveguide for microwave application)" Slotted pipe discussion on DIY http://www.diyaudio.com/forums/multi-way/273667-karlsons-slotted-pipe-tweeter.html 5. Website devoted to Karlson http://home.planet.nl/~ulfman/

Very cool!

Cross Braces are one possible solution for managing vibration. I'm hoping to keep this Thread as something of a "list of ideas and links" to other treads so we don't glaze over with the sheer number of posts. Can someone open a Thread on La Scala Bass Box Vibration Management and Modifications: Cross Bracing approaches and Layering the cabinet, and link to it here? Something like Full Range in Brisbane has done with his robust DIY crossover discussion thread.

Very cool At the end of the day, the designs always come down to bench testing and tweaking. It's good you are keeping score, so you can experiment with changes and measure the effect. I assume you are going for the elusive linearity.....

I have been considering building a brace that uses felt tabs so they are not permanent. Currently I have a cam shaped tool to assist the installation. http://www.fastlaneaudio.com/ez-brace-instructions..html I just installed a set of Dave's braces and used his prototype cam tool. Both worked perfectly. Really makes the bass sound more accurate to my ears. HTH, Mark If you put your hand on the side of the woofer section is the vibration gone?