djk

quote: Originally posted by Jim Gieringer: Here's pics of PD-20 drivers. Point well taken on choosing the correct parts. Consider my friend with the rusty old AMC Gremlin... he puts on $10 used tires when he gets a flat and doesn't buy $200 Pirelli's! Jim Very good shots.A PD20 has a 1 1/2" coil and no phase plug.Its frequency response looks like a 1kz bandpass filter.No high end ,no low end.

quote: Originally posted by Al Klappenberger: Hi Guys, yes, the K55V driver will require a tap on the T4 transformer that isn't there. You will have to replace the T4s with the UTC T2a upgrades and use tap #4. Th T4 only has tap #3. Al K. Al,If you look at Jim's photos closely you will see that the top plate is pinned to the magnet so it it most likely a PD4 and not a PD5 which has six screws on top.The PD4 has no phase plug,no high end,no efficency,and is no longer made.It is possible to make work with a tweeter that goes to 2khz and a whole different network.

quote: Originally posted by Jim Gieringer: Does anyone have a pair of LaScala Crossovers they would like to sell? I picked up a pair of solidly built homebrew LaScala's for $20! but one is missing its xover. The ALK's are Very Nice but TOO nice for these, new ones from Klipsch are listed at $152 ea., I'm hoping for a budget-priced pair to get these playing! A few people have referenced kits for the LS - could someone pass along internet sites that have the plans? I'm curious as to their origin. The fiberglass mid-horns are pretty nice but thin and seem larger than original Klipsch. The crossover doesn't look like other Klipsch X/O's I've seen. The mid compression driver is an Atlas PD-20. The highs are a metal horn Radio Shack, larger than the EV T-35's. I'm not sure what make the woofers are, haven't figured how to get into the chamber yet. I posted some pictures & drawing with dimensions of these spkrs at http://www.cyberhighway.net/~jpg/LaScalaCopy/ Thanks, Jim LA SCALA K-33-E WOOFER 121501 100.00 K-55-M MIDRANGE ***'Y 128005 186.00 K-77-M TWEETER ***'Y 129001 198.00 K-401 HORN 130117 196.00 NETWORK (AL-3) 116005 152.00 A friend of mine owns a Ferarri.Sort of.Its actually a Fiero with a kit car body.If he needs a fuel pump he goes to the Pontiac dealer.Your cabinets look pretty well built for home made.But you can't just buy a pair of Klipsch networks for them.That looks like an Atlas PD4 not a PD20.It doesn't matter because neither will work well with a stock LaScala network.Ditto the tweeter.I cut and pasted the MSRP for the parts you need up above.Remember you need two of everything.I have a used pair of AA networks and the matching tweeters,mid drivers and mid horns.The tweeters have new diaphragms.I would drop them off at a pack and ship place for $350.Buy a new pair of K33E from Klipsch for $200 and you are in business.$1664 for new LaScala parts with AL3 networks or $550 for used K55V mids and AA networks with new woofs and tweets.

quote: Originally posted by steve: djk..I tried (as have many) other alternatives, like the dynamat trick, clipping the epilyectic (sp?) filter, etc with the speaker itself. While this did indeed accomplish some sonic improvements, they were (as stated in posts before this) "tweaks". YES, improvements, but small in size! Steve When I pointed out to my mother that it was a waste of time to wash the storm windows before hanging them every fall because the inside windows were dirty I had to wash them too.Then it rained right after I got them all up.So much for being right.I'm glad you finally got yourself a good sounding amp.Now you can hear the benefits of damping your horns and eliminating the eliptical filter that were barely discernable to you previously.I have always had access to state-of-the-art electronics so my experience is different than yours.After reading the Richard Heyser review of the Klipschorn in Audio about 12 years ago and his comments about the time/energy response in the 6khz region of the tweeter I realized what the problem was.I dashed behind the Klipschorns with a pair of wire cutters and snipped out the eliptical filter.The change was so obvious that everybody asked me if I had cut out the tweeter.Female vocals show the biggest change.The tonality of the horn ring is quite different between the metal and plastic horns.The metal horn lacks damping.The plastic horn lacks rigidity.I find it easier to make the metal horns sound better.

quote: Originally posted by steve: If I may add my 2¢ worth..you wouldn't have to change a thing with your horns..if you'd go tubes! I changed equipment (solid state) constantly, to avoid the "brightness" of my K-horns..then I realized that they weren't bright when I played LP's (records for you young folk). I never experienced a problem, even with SS gear until CD's came along..but when they did, I found that tube gear made all the difference! Try an Assemblage amp (SET 300B)..you'll love it!! I sure do! My hunt for equipment ended March 2K!! Steve Perhaps you could explain to us how using a tube amp damps the horns and stops them from ringing? For a rude shock play some FM interstation noise through your speakers and then push the tape monitor switch.Now put on a solo piano piece.That ringy/overhang sound turns a lot of people off.These guys have some good ideas that are low cost,work well,easy for DIY,and reversible if you don't like the results.

quote: Originally posted by William F. Gil McDermott: Hmm, very interesting on the updated 1570. I bought mine several months ago. My recall is red flecks. You've invited the question: What did they change . . . and if you know, why? Gil A fair question.Easier to answer what they didn't change.The model number of the speaker and the diameter of the cone.Their main market for these is car stereo.The tinsel leads are better on the new ones,and the way the tinsel leads are terminated is better.The frame although thinner actually looks stiffer due to the stampings.It didn't sound as good as the old style so I sent the pair back.I do some mods to LaScalla's and these require the woofer to have a Qts~.3 the Fs~30hz and the Vas~10cu ft(similar to the K43).An EV DL15W works ok but is 8 ohms(requiring a network change)and more money.The original Pyramid 1570 worked pretty good and was dirt cheap too.

quote: Originally posted by William F. Gil McDermott: If you want a suggestion on an alternate driver for a K-Horn and SK, I'm using a Pyramid 1570 from Parts Express. It works for me. I can not claim it is "better" than a K-33 or K-33-E. However, if you're a tinkerer, you might give it a try. Regards, Gil Pyramid changed the design of the 1570 about two years ago.The original was a very good replacement for the K33E.What they are shipping now is not.If the front gasket is two colored speckled cork it is the newer type.

quote: Originally posted by Stig: djk, Sorry for my late reply but I've been out looking for that " all hardwood, no void, 18 ply per inch 12mm baltic birch". In your post you say it got narrower inside. A change from 1/2in. to 3/4in. would have changed "ALL" internal dimensions. I was under the assumption that horns had to be built precisely. From what I'm reading all over the BB it seems that if I build a pair of horns and I'm off a 1/4in. here a 1/2in. there that it wont matter because they are only approximations of a certain flare rate. If that is true why is the Khorn so intricate and so *********** hard to build? Ain't this horn stuff fun. Thanks, Stig Baltic birch is usually delivered by pool trucks from(for where I live)out of state distributors."B" faces 5'x5' only.They have a truck that makes a route all the small yards and cabinet shops every two weeks.Call a local cabinet shop and see where he gets his from.Appleply is an American product with poplar and alderwood cores and maple faces,one inch has a total of twenty plies."A" faces 4'x8'.Finnform is used by people that pour concrete,similar to Baltic birch but not sanded.Many sizes available.I made 24 LaScala sized bass horns in 1978.I added corner reflectors and increased the 'shrunk' dimension back to 3" and changed the internal doghouse dimension to 15 3/4" to accomodate non-Klipsch woofers.The higher in frequency the horn operates and the closer to the throat you are the more important the dimensional accuracy is.After making eight pieces I left out the corner reflectors.Four of them had a 1/2" error in the location of the slot in the motor board.They all sounded the same.I carried twelve around in the back of a bus for about five years.They start to thump pretty good when you use four per side.I was able to build 24 bass cabinets out of 25 4'x8' sheets.About four hours per box for build time.The K-horn is much harder to build because of the compound miter joints and the fasteners going in to the edge of the 12mm ply.A good winter project for the the Inca or Powermatic 66 owner who has a shuttle box.Buy a used pair.

quote: Originally posted by cls72: Yeah thats what I thought too. They were playing clearly without scratching but there was just no volume. When I took them apart the magnet structure fell apart but i didnt think at first that it would make a difference. Hmmmm, how would I make them work again? Replacing the diaphragms is not as simple as "do it".I have done over 100.Three points.Mark the location of the crossover lead,the wire going from the bottom of the coil to the top,it determines polarity.Make sure this lead fits into the slot milled into the top plate,otherwise it will rub.If the top plate of the magnet moves during dis-assembley throw it away.On alnico magnets they go dead if this plate moves(cls72).On ceramic magnets if you can get it back to within 25uM(0.000984")it will be fine.This is almost impossible to do because the magnet makes it wants to pinch over.Depending upon the adhesive EV used and the age of the tweeter success rates were from 80~90%(in other words I had to throw it away as often as one out of five repairs).A speaker repair shop mith a magnet charger can repair them.

For half space loading(on the floor)the sides of the mouth need to be a 1/4 wave long.The mouth size of the LaScala is good for about 128hz.Olson suggests that the taper rate be set about 1/3 octave lower than this(ie about 100hz).The taper rate of a LaScala would seem to be 8"(ie 100hz)average,ignoring the short non tapering segment.Measuring a LaScala in true half space it peaks at 125hz on a 1/3rd octave RTA and is down about 10dB in the 50hz band.This is consistent with the Klipsch spec of a 10dB envelope(+/- 5dB) from 45hz to 17khz.In PWK's article "A Low Frequency Horn of Small Dimensions"(JAES vol 13,#2 137~144)he cites Olson in describing a 100hz horn with a 25" mouth and a 8" taper rate.He then goes on to describe the K-horn as being a multiple taper 8"(100hz)changing to a 16" taper(47hz).He then states "The cut-off of the horn is 47 cycles and the computations show poor performance below 55 cycles".This is consistent with the Klipsch spec of a 10dB envelope(+/- 5dB)from 35hz to 17khz.If you need actual horn loading to 80hz you need to scale UP the dimensions of the LaScala,not make it smaller.PS,the THX approved 500hz high frequency horns from JBL have 32"x32" mouths and the EV and Altec horns are even larger.

quote: Originally posted by Stig: Volvotreter, Now I have seen three different sets of plans showing different dimensions in this parallel area. One with 2.5in. by 23in., another with 2.75in. by 22.25in. and the last with 3in. by 23in. Is there "ANYBODY" on this BB that knows if the La Scala was ever made by Klipsch using different internal dimensions for the horn? Where is the Klipsch historian when you need him? How 'bout if everybody that owns La Scala's gets a tape measure and posts their internal horn dimensions. That would put it all on the table. Ain't this this horn stuff fun. Stig The answer is really quite simple.The LaScala was originally made from 1/2" plywood so the dimension in question was 3".When the price was lowered in the 70's the expensive all hardwood,no void,18 ply per inch 12mm baltic birch was changed to ordinary 3/4" 7 core softwood plywood with birch faces.The external dimensions were unchanged so it got narrower inside.