what's wrong with LS II?!

[Islander]

There should be nothing in between the speakers. Roy Delgado has always emphasized this but hardly anyone pays attention to it. Try it sometime and see how the bass and image improves. The speakers to the outside are too close effectively enclosing the lascalas. Get them away from the lascalas.

My guess..........nothing wrong. Put them in corners, nothing in between them. Try some different equipement and stay away from high current ss. That's probably the best you can do.

It's usually recommended that anything between the speakers should be recessed, relative to the fronts of the speakers. If the speakers can "see" each other, whatever is in the middle is far enough back. Could that be what Roy meant? I've never heard of needing the space between the speakers to be actually empty.

The setup in the pictures shows the electronic stack to be a good 8" back from the line between the fronts of the speakers. I'd have thought that's enough.

The Klipsch Heritage manual states "Angle speakers toward the listener and even with or forward of any adjacent obstructions." Roy knows best, of course, but following the instructions in the manual should provide at least good sound, if not the perfect ideal sound.

As for the outboard speakers enclosing the La Scalas, is that a bad thing? Isn't that what a wall would do, if the speakers were in corners, as is often recommended?

[garyrc]

It's usually recommended that anything between the speakers should be recessed, relative to the fronts of the speakers. If the speakers can "see" each other, whatever is in the middle is far enough back. Could that be what Roy meant? I've never heard of needing the space between the speakers to be actually empty.

I would consider the best starting position to be what PWK recommended for any speaker, deep into the corners and toed in. For horn speakers, I believe he suggested being in a position in which you can look down the throat of the mid horn and tweeter. Once you toe in, any objects between the speakers are more "in range" of the mid and hi speaker dispersion, so stuff between the speakers probably shouldn't be there.

From that starting position, one could move the speakers around, particularly forward into the room, just to see what that would do.

I'd think that a thick carpet and a high ceiling would be beneficial, as Heyser suggested with Khorns. But, empiricism trumps reasonable prediction, so variations should be tried.

Old Linn suggested that no other speakers be anywhere in the room, let alone nearby, but I always thought that sounded like a highly convenient POV for someone wanting (understandably) to sell his brand of speaker.

Roy, where are you? We'd love for you to weigh in.

[mark1101]

One of the issues I had with LSII was the complicated networks. Take a look at them. Lots of components (and cheap ones).........and you can hear them. The speakers probably measure good in a chamber but you can hear the life has been sufficiently sucked out of the music. Especially compared to an older pair of LS with decent networks that employ higher quality parts.

Same issue with the latest K-horns. When I was at Klipsch and heard the Khorns they had on display I am sorry to say they sounded like garbage. At the time I had Khorns as well and the minute I heard those at Klipsch it was a big problem for me. Mine sounded 10 times clearer and more open.

In the OP picture I also see unnecessary treatments on the wall behind the speakers. How would someone even know to put those there? What measurements told you to put those there? What improvements do you notice?

[mikebse2a3]

the weak point of the sound was low frequency. the bass was somehow rippled, as if K-33 was struggling in the dog house, the sound came out as if you are watching a movie at 5 frames per second! mid-range was normal and trebles were revealing well. everything was good except that bass I mentioned which dominated all the sound. I was experiencing listening fatigue after 10-15 minutes! now I think maybe it was something about phase of the speakers. they sounded like woofs were pushing backward!

Hello arash,

IMHO forget all the [bs] about the networks. Excellent sound is available with the LaScala II if the room and setup is done properly.

The advise to check for the proper wireing of the speakers definitly needs to be done.

The room as pictured shows very poor setup of the system. Even worse is the fact that the very high percentage of foam (as well as the fact that the foam is also very frequency band limited) is creating a very unbalanced room response. The room as treated will exhibit high listener fatigue with a very unnatural tonal balance and decay of sound across the frequency spectrum.

PWK warned decades ago that often the loudspeaker is blamed when what really is the problem is the room's acoustics......and this room/setup is an excellent example of such a case.

Best of luck arash but unless they deal with the room I have little hope that you will hear the LSII as they are capable of reproducing sound.

miketn

[ZombieWoof]

Yeah ,I agree with Mike ,it's the room & set-up

[Guest " "]

sure...side by side in stereo scope mode they will sound horrible. They need to be placed into corners toe'd in to the listening area. The bigger the triangle (left speaker, right speaker, listener) the better they will sound. I like them at 21 feet apart and my position 21 feet back. Also, not sure if that tube amp has the right stuff at the bottom end to control the woofers.

[Islander]

One of the issues I had with LSII was the complicated networks. Take a look at them. Lots of components (and cheap ones).........and you can hear them. The speakers probably measure good in a chamber but you can hear the life has been sufficiently sucked out of the music. Especially compared to an older pair of LS with decent networks that employ higher quality parts.

When I first heard La Scala IIs, I thought they sounded good, but not great. Since I wouldn't be using the HF sections, I didn't worry about it.

I bypassed the network issues when I bypassed the networks on my La Scala IIs and used an active processor (Dx38) instead. Using the LS2 bass bins and K-69 Jubilee tweeters produces great sound, and it's unmistakeably better than with original La Scala bass cabinets.

[tigerwoodKhorns]

One of the issues I had with LSII was the complicated networks. Take a look at them. Lots of components (and cheap ones).........and you can hear them. The speakers probably measure good in a chamber but you can hear the life has been sufficiently sucked out of the music. Especially compared to an older pair of LS with decent networks that employ higher quality parts.

When I first heard La Scala IIs, I thought they sounded good, but not great. Since I wouldn't be using the HF sections, I didn't worry about it.

I bypassed the network issues when I bypassed the networks on my La Scala IIs and used an active processor (Dx38) instead. Using the LS2 bass bins and K-69 Jubilee tweeters produces great sound, and it's unmistakeably better than with original La Scala bass cabinets.

What is the crossover frequency to the K69 and 510 horn?

[Islander]

What is the crossover frequency to the K69 and 510 horn?

The setting for the bass high-pass is 420 Hz and the treble low-pass is 470 Hz, both set for a 24 dB/octave Linkwitz-Reilly crossover. The average of those two numbers is 445 Hz, but I don't know if the calculation is as simple as that.

You would think that leaves a gap in the middle, but apparently not: http://en.wikipedia.org/wiki/Linkwitz%E2%80%93Riley_filter

More info: http://www.rane.com/note160.html

A bit from Linkwitz himself: http://www.linkwitzlab.com/crossovers.htm

This level of audio theory is way over my head, so I just punch in Roy's lab-tested settings and enjoy the sound. One interesting thing about having the crossover frequency set so low is that the tweeters wind up covering more of the audio spectrum (more octaves) and power than the woofers. As a result, the treble amp runs a little bit warmer than the bass amp.

[Coytee]

For anyone reading and unaware... for those who are using an active crossover, Roy has a -7 db PEQ (Q=8) at 148hz. My understanding is this is to help tame the sidewalls on the original LaScala from resonating as much.

I don't know if it's as beneficial to the LSII.... Pat.....thoughts??? (I wonder if you could bypass that and get some better punch?)

[moray james]

I think that I wouuld give Roy the benefit of the doubt, if he says it works I would go with that. The best way to get more punch and impact out of any horn is to insure that the mouth is rigid. So for the LaScala one or two cross braces would be the order of the day. Best regards Moray James.

[Islander]

For anyone reading and unaware... for those who are using an active crossover, Roy has a -7 db PEQ (Q=8) at 148hz. My understanding is this is to help tame the sidewalls on the original LaScala from resonating as much.

I don't know if it's as beneficial to the LSII.... Pat.....thoughts??? (I wonder if you could bypass that and get some better punch?)

That's actually a misconception. Resonance of the sidewalls absorbs energy, so it results in less volume, not more. In the same way, a properly-balanced engine makes more available power than a poorly-balanced one, since all the power is being used to turn the crankshaft, instead of some being wasted shaking the engine.

That narrow peak at 148 Hz is caused by the shape of the horn, so it exists with the La Scala II as well. I seem to recall seeing that in a post or message from Roy. It's not noticeable most of the time, but when listening to The Strat Pack DVD (a celebration of the 50th anniversary of the Stratocaster, first released in 1954), which is a 2004 concert featuring lots of top guitarists playing Strats, that bass peak caused the drums to sound really annoying. I only listened to that DVD partway through, once or twice, because of that.

Once I had done the JubScala conversion, and the 148 Hz peak was dialed out of existence, it was a pleasure to listen to that DVD for a change, and I was able to listen all the way through.

The LS2 bass horn is very similar to the original LS horn, but there are at least a couple of subtle differences. First, there's no step at the front end of the straight section. The joint where the straight part meets the front tapering section is very smooth.

Second, the horn is 3/4" longer, measured from the inside of the back wall to the front of the cabinet. You can easily see that the point of the Vee of the doghouse is further back from the front of the speaker.

I may be wrong, but I suspect that the narrow 148 Hz peak would be nearly impossible to remove with a passive crossover, but it's not apparent most of the time, so perhaps it was just accepted as an inevitable compromise that allowed an advantage somewhere else. Going with the active crossover allowed that peak to be tamed, and a number of other peaks and dips to be corrected at the same time. The result is that the JubScala has a more accurate frequency response than a standard La Scala.

[Islander]

I think that I wouuld give Roy the benefit of the doubt, if he says it works I would go with that. The best way to get more punch and impact out of any horn is to insure that the mouth is rigid. So for the LaScala one or two cross braces would be the order of the day. Best regards Moray James.

You're right; a horn should be absolutely rigid, so sound energy is transmitted and not absorbed, but in this case it's the mid-section of the horn, not the mouth.

Stiffening the La Scala bass horn should improve its output, whether by adding braces to the inside or adding to the outside wall thickness. However, the difference between the first-generation La Scala and the LS2s is not due simply to the cabinet being made of 1-inch material instead of 3/4-inch material.

Prototype LS2s were built of plywood and of MDF, and when they were compared, the consensus of the engineers was that the MDF LS2 sounded better. The extra 3/4" of length of the LS2 bass horn likely also helps it to go a few Hertz lower than the first-generation LS horn.

[mikebse2a3]

The extra 3/4" of length of the LS2 bass horn likely also helps it to go a few Hertz lower than the first-generation LS horn.

Hey Pat

It helps to think of wavelengths and in this case 3/4" extra length is insignificant at the low end response capabilities of the horn.

For example: Sound travels approx 1130' per second thus 1130' x 12 =13560" thus as can be seen in these two examples no significant low end extension is acheived by 3/4" path length difference.

50hz wavelength = 271.2" and a 49hz wavelength = 276.73".

The perception of an extended low end is the results of a flatter frequency response of the LSII.

miketn

[Islander]

Thanks for doing the calculations, Mike. That makes sense, so I wonder why the horn (and cabinet) is that bit deeper? Could it just be for looks or manufacturing convenience? Also, the specs show the bass going a little lower than the first-generation model (51-17kHz vs 53-17kHz), so I don't think it's just a listener's perception, unless Klipsch has starting fudging specs a bit.

The sensitivity spec is also up 1 dB, from 104 to 105, along with the maximum acoustic output (121 dB SPL vs 120 dB), so the stiffer horn sidewall seems to be absorbing less energy and letting it exit the horn.

[mikebse2a3]

Thanks for doing the calculations, Mike. That makes sense, so I wonder why the horn (and cabinet) is that bit deeper? Could it just be for looks or manufacturing convenience?

That would be my guess.

Also, the specs show the bass going a little lower than the first-generation model (51-17kHz vs 53-17kHz), so I don't think it's just a listener's perception, unless Klipsch has starting fudging specs a bit.

I don't think Klipsch is fudging specs Pat. I believe they probably have more accurate test equipment than in the past and it's possible variations in data gathering methods have changed over the years as well as driver and crossover design changes could easily explain these very slight variations in specs.

If you also look at the Klipschorn for example it used to be rated 35hz - 17.5khz (+/- 4db) and 104db @ 1m/1w but the current model is rated 33hz - 17khz (+/- 4db) and 105db @ 1m/1w.

These very slight specification variations are in themselves insignificant IMO and wouldn't explain the perception that the LaScala II reaches lower than the first generation LaScala. What would cause the perception of a cleaner and extended LF response IMHO is a smoother response due to current crossover design along with better control of the sidewall resonances. These 2 factors will reduce any masking effects that the side wall resonances caused and detail/clarity and transient dynamic details will be better perceived.

The AK-4 along with current drivers when I installed them in a friend's KHorns exhibited these very improvements also IMHO.

The sensitivity spec is also up 1 dB, from 104 to 105, along with the maximum acoustic output (121 dB SPL vs 120 dB), so the stiffer horn sidewall seems to be absorbing less energy and letting it exit the horn.

Again see my previous comments about the Klipschorn which shows similar changes in the specs and I believe points to changes in the current methods of data gathering as well as driver/crossover improvements for smoother frequency responces even if the overall trend stays within in +/- 4db window.

miketn

[Islander]

These very slight specification variations are in themselves insignificant IMO and wouldn't explain the perception that the LaScala II reaches lower than the first generation LaScala. What would cause the perception of a cleaner and extended LF response IMHO is a smoother response due to current crossover design along with better control of the sidewall resonances. These 2 factors will reduce any masking effects that the side wall resonances caused and detail/clarity and transient dynamic details will be better perceived.

The AK-4 along with current drivers when I installed them in a friend's KHorns exhibited these very improvements also IMHO.

miketn

In the case of the JubScalas I'm using, the improvements the AL-5 crossovers may bring are irrelevant, since I've bypassed them and I'm using the Dx38 instead. The sound of the LS2 bass horn and woofer is a lot better in terms of fullness and clarity than that of the 1974 La Scala LF section I was using. I don't know if it goes all that much lower, because I'm using a sub, and I haven't taken the time to do any exhaustive testing with and without the sub. I'm just listening and smiling.

It could be that the old woofers are way past their best performance, but they always seemed fine. Even more noticeable than the improved on-axis sound is the improvement in off-axis vocal clarity. Now, when I'm at the computer, down the hall and three rooms away from the speakers, I can easily follow a discussion on talk radio, something I could not do before, unless I cranked the volume extra high.

The more rigid sidewalls must help, but eliminating the step on each side of the doghouse likely reduces distortion. Before I had custom Plexi stands made for the 510 horns, they were supported on blocks of Styrofoam, which were an inch or so back from the front edges of the cabinets for safety, since the Styrofoam and the felt pads under the horns and brackets were a bit slippery.

I asked Roy if the two steps (horn flange to front of foam block, and front of foam block to front of cabinet) would cause any problem and he replied that there would definitely be anomalies caused by diffraction, IIRC.

Accordingly, I had the stands made to allow the horns to be flush with the stands, and the stands to be flush with the cabinet fronts. The difference was audible. When I put on a song with really low-level background vocals, before and after installing the new stands, it was easier to make out every word with the new stands.

I still remember and appreciate the help you gave me when I first got the 510s and the Dx38, and my knowledge is still no match for yours, but that's what I'm hearing, and it's completely consistent every day.

[garyrc]

If you also look at the Klipschorn for example it used to be rated 35hz - 17.5khz (+/- 4db) and 104db @ 1m/1w but the current model is rated 33hz - 17khz (+/- 4db) and 105db @ 1m/1w.

I thought it used to be rated 35 - 17.5 KHZ +/- 5 dB, then 35 -17KHZ +/- 3 dB, and finally 33 - 17KHZ +/- 4 dB. I can't put my hand on my old data sheets, so maybe I'm wrong.

As to the efficiency, several years ago someone posted that they were told at the factory that the 104 dB was an error, and simply corrected to 105 dB without a change in real efficiency. My guess is that it wasn't so much an error as a difference in distance. The Klipschorns of the (early?)1970s were rated at 104 dB at 4 feet, while the new ones are rated at 1 meter. When the new rating distance of 1m became customary, someone may have forgotten to change the 104 to 105 -- or perhaps thought, "well it's conservative." Incidentally, the 4 feet @104 was equivalent to 54 dB EIA, according to PWK. The raw (no crossover) JBL D130 also measured 54 dB EIA within its narrow relatively flat range, and JBL rated it at 103 dB, 1 wt, 1 m. Maybe it depends on the range of frequencies used by the various people doing the ratings in those times to establish the efficiency.

I don't know when Klipsch got its revolving corner anechoic chamber, but I think it was somewhere between 1975 and 1978, based on where I was living when I got the ad.

[mikebse2a3]

In the case of the JubScalas I'm using, the improvements the AL-5 crossovers may bring are irrelevant, since I've bypassed them and I'm using the Dx38 instead. The sound of the LS2 bass horn and woofer is a lot better in terms of fullness and clarity than that of the 1974 La Scala LF section I was using. I don't know if it goes all that much lower, because I'm using a sub, and I haven't taken the time to do any exhaustive testing with and without the sub. I'm just listening and smiling.

Pat without a doubt your system is much different than a stock LSII. I suspect Roy used the DX38 programing ability to assist in the dialing in of the acoustical response corrections and voicing of the AL-5 crossover in the stock LSII (I know he did that with the passive Jub/K402/TAD design) and the two were remarkably similar in sound IMO). Most of my comments are in reference to stock units of both the original LaScala vs the LaScala II and also the differences in their LF sections.

Before I had custom Plexi stands made for the 510 horns, they were supported on blocks of Styrofoam, which were an inch or so back from the front edges of the cabinets for safety, since the Styrofoam and the felt pads under the horns and brackets were a bit slippery.

I asked Roy if the two steps (horn flange to front of foam block, and front of foam block to front of cabinet) would cause any problem and he replied that there would definitely be anomalies caused by diffraction, IIRC.

Accordingly, I had the stands made to allow the horns to be flush with the stands, and the stands to be flush with the cabinet fronts. The difference was audible. When I put on a song with really low-level background vocals, before and after installing the new stands, it was easier to make out every word with the new stands.

This is exactly what I was refering to Pat when I said it helps to think about the wavelengths being reproduced as a guide to decide if steps and other physical disturbances will cause problems. In your case the K510 is being asked to reproduce wavelengths from approximately (400hz = 33.9") to (17khz = .79") and at the lower end of this range the stands and their steps will have little if any effect but as the stands and steps dimmensions begin to approach a significant fraction of the wavelengths being reproduced and reflected from these physical disturbances anomalies will be observed. Your improved stands look to be well designed to reduce some of these anomalies.

My point with the 3/4" step in the original LS's LF is that it is insignificant compared to the wavelengths involved and also considering it's distance location along the path length of the horn. What will make the original LS's LF horn match the improved LS II's LF horn is bracing of the side walls because just applying some eq at this resonance point will never equal stoping the resonance from developing in the first place.

I still remember and appreciate the help you gave me when I first got the 510s and the Dx38, and my knowledge is still no match for yours, but that's what I'm hearing, and it's completely consistent every day.

Pat I hope you aren't thinking I'm questioning the improvements that your hearing because in fact I would expect exactly the sound reproduction improvements your system is delivering for you. In fact I believe your total system's design of using a Sub, LS II's LF, K510 and Active Crossover is an excellent one.

miketn[]

[mikebse2a3]

I thought it used to be rated 35 - 17.5 KHZ +/- 5 dB, then 35 -17KHZ +/- 3 dB, and finally 33 - 17KHZ +/- 4 dB. I can't put my hand on my old data sheets, so maybe I'm wrong.

Your right Gary as over time Klipsch marketing material specs varied and by themselves gives very little indication of how the system will sound. They shouldn't be used to decide if system improvements have been made by themselves.

miketn