Chris A

Uhmmm---no. Basically, it was the other loudspeaker. Perhaps. I've found that any loudspeaker can be dialed-in over time to a room and listening positions, so getting equal time/effort in for each loudspeaker usually doesn't occur in these instances unless significant time with each is expended. For instance, it took me almost 12 years to really get my left/right loudspeakers (Jubs with TAD 4002s) dialed in correctly. Once that was done, they provided a totally different listening experience. YMMV. Chris

"Happy [loudspeakers+listening room] are all alike; every unhappy [loudspeakers+listening room] is unhappy in its own way." (With sincere apologies to L. Tolstoy) There are many ways to go wrong with loudspeakers and listening room acoustics, and I think that the two questions posed above begin to highlight a very small subset of those unhappy ones, but there is really one way to get everything right--and I find that few loudspeaker designs really achieve that--far fewer than what "audiophile reviewers" recommend, unfortunately.

You might be surprised to find that there are many people that really aren't looking for that. What you described implies accuracy or at least "neutrality of sound quality". The individuals that I've identified aren't looking for that. And I believe that we shouldn't be terribly worried about addressing those individuals from this particular forum. YMMV. Chris

That's a fairly tired argument that you've chosen to inject. Claude, this is an instance where I don't believe that I need help. Accurate sound is always defined as "reproducing what the recording has presented--as accurately as possible". But I believe most here already got that. Chris

Some people apparently aren't looking for "accurate"...and in the case that I quoted, that was one of those instances. It's better to know that up front before making any suggestions. When someone says that they aren't looking for the biggest soundstage possible, that it's "too wide and too tall" with a certain loudspeaker, that's a case of them wanting something that isn't an accurate reproduction of the real thing. Another instance is where they want the loudspeakers to magically "correct" their music tracks that have been subjected to huge amounts of limiting (clipping--more than half the waveform is clipped)--which sounds very harsh when played back on a good, accurate set of loudspeakers, then that's another case of them saying that they don't want accurate sound. They instead want loudspeakers that camouflage that clipping (i.e., very low efficiency direct radiators that "round off" the transients--whether it's desirable or not). I find these instances occur fairly regularly with those that listen to music genres that do not approximate an accurate acoustic performance--such as electronica and extremely heavy rock derivatives--to the exclusion of every other genre. That's what I'm referring to when I say "trying to reproduce an aesthetic". Chris

Below about 50-60 Hz, if the output of the subwoofer is very clean, (i.e., it has very low harmonic distortion), I've found that subwoofer localization in-room is virtually impossible. If you can hear a subwoofer's location while it is playing below ~60 Hz, what you're probably listening to its distortion, not the signal being fed to it. When I compare the output of my TH subs (DIY "SPUDs") in their positions behind the Jubs, they are basically impossible to locate below their 40 Hz low pass crossover frequency, i.e., I have to turn each one on and measure them separately to sense that each is playing as it should. What this placement does is allow the extra absorption around the Jubilees and subwoofers to absorb the higher frequency harmonics--because that material just isn't effective below ~100 Hz, so that absorption material really can't absorb the prime output that is actually sought below 100 Hz. This is quite a different experience than those I've had with direct radiating subwoofers. This is usually a very unpopular subject, especially among those that promote direct radiating subwoofers over well designed horn-loaded subwoofers. This is the same kind of idea that Earl Geddes uses in his Summa series models (i.e., whose horns that he filled with open-cell foam) to attenuate the off-axis higher order modes (HOMs). Chris

I always expect that a price ceiling will be quickly determined in every case--either explicitly by the requester or inferred through dialog with him/her. That's usually not an issue. But I've seen the two questions (the two posed above) forgotten quite often: the reason for this thread. I've seen more than one "round trip to Abilene". Chris

Probably not too many forum members are going to applaud the above remark...because those that respond to these type of questions typically want everyone else to like the loudspeakers that they think are best i.e., (in their own usage). I find that first trying to understand the requester's needs/viewpoints--then, wishing to be understood (just like The Seven Habits advocates), there are really two questions at a minimum to ask of those asking for guidance on loudspeaker choices. If the OP will not answer the following two questions (or instead answer them quite poorly) before receiving their recommendations, I'd personally pass on trying to help them: "What exactly do you listen to (i.e., albums/tracks) if making speaker comparisons?" I find the answer to this question is a major determinant of satisfaction with loudspeakers in real listening rooms. If they listen for realism in playback of acoustic performances, they'd probably prefer certain Klipsch loudspeaker models. If instead, they listen for a certain "aesthetic" (i.e., mostly popular music that was not produced with "accuracy" in mind), then they might tend to prefer other types of Klipsch models, etc. If they were willing to enumerate a few of the particular recordings that they are using to make their judgments, I think it would be much easier for others to understand what the requester is looking for. Can they list some of the recordings (by track name) that they presently listen to? "Can you tell me about your listening room...?", i.e., height, width, and depth--all three dimensions, since many Klipsch loudspeakers don't do very well in rooms with less than 9'/2.7 m ceilings. Getting an idea of the volume of their listening room is a strong determinant of what's going to work well and what isn't, i.e. Klipschorns in 800 cubic feet listening rooms probably isn't the best suggestion to give them, nor is the suggestion to put bookshelf loudspeakers in rooms having 5500 ft3 /170 m3 into your suggestions. Also, finding out where they plan to put the speakers in-room, and whether or not the room is comprised of bare concrete blocks, or fully acoustically treated floor/walls/ceiling (and whether or not they'll even consider adding these items), will, in my experience, strongly determine what you would recommend without yet again invoking "the Abilene Paradox", like the quote above apparently did recently. Chris

Well if we're doing this, here's some more for those that care to remember PWK and his unique audio philosophies (as I try to), plus some other "audiophile pundits" along the way: Chris

Unless of course you're using K-402s...in which case, the entire front wall of the listening room becomes the soundstage (much like a good commercial cinema experience...imagine that...😉) Here is an approach that dispenses with the large "W" section bass bin, producing a Cornwall-sized fully horn loaded loudspeaker, the K-402-MEH, which actually does not require a corner--but benefits greatly if placed there): However, this thread is about Heresies, not La Scalas, Jubilees, or MEHs. It's probably best to leave those other subjects alone in this thread. We typically listen mostly in the 65-75 dB range (average), and only get up to ~83-85 dB (average) during videos. It's the sense of realism that is the real attraction. There is no limitation to how soft or how loud. Chris

Well, about 10 years ago, I created a thread on that subject: Chris

All loudspeakers have room-dependent SPL response below the room's Schroeder frequency (nominally 200 Hz for many/most home-sized listening rooms). The reason for the uneven response of the La Scala bass bin is two-fold: its undersized horn mouths for the size of acoustic waves developed internally (an issue with most bifurcated "W" section bass bins), and the La Scala bass bin is coupling to the room (i.e., boundary gain) due to its increased efficiency over direct radiating designs. If other (direct radiating) loudspeakers are so inefficient that they can't as effectively couple to the boundaries, then they suffer from not being able to effectively make use of that boundary gain. PWK wrote an article discussing this physical phenomenon, advocating that any loudspeaker does better in a room corner, with suitable EQ to flatten its response again to lower overall bass distortion: https://community.klipsch.com/applications/core/interface/file/attachment.php?id=66006 Chris

This is basically correct. This is actually incorrect--in fact very incorrect. Note the measured harmonic and modulation distortion output...at 110 dB (1 metre)! One of the great advantages of the La Scala is the performance of its 180 degree folded horn bass bin. There are no direct radiating bass bins that can do all of the above. I'm amazed that more loudspeakers don't take advantage of this design (now ~60 years old). Only the knock-off Volti Vittoria and perhaps one other (expensive) handmade European loudspeaker reuses the La Scala's design--to great advantage. Chris

Mark, I think you missed two key words: "...fundamental differences...". I do acknowledge your apparent effervescent personality and your characteristic lack of being dissuaded. The problem is when you show (to me, at least) that you really don't understand the basic physics. And in apparently not wishing to deal with that, choose instead to forge ahead rather forcefully voicing your own opinions--which I've found to be poorly calibrated. You then typically seem to exercise what I consider to be questionable observational capabilities (i.e., lack of care in understanding the root causes of phenomena measured and sensed), and compound that with what I see to be poor judgment...both in informational threads that I have set up over time. The problem is that you don't seem to relent until someone has to tell you this so explicitly, and for that I really do apologize that I have to be so explicit, because I find it distasteful that I have to say it here. You've apparently followed me to this forum from diyAudio, itself looking like a predatory gesture. It's a simple request: could you please start your own threads that you've set up for yourself and please not leapfrog into the threads where I've put in a fair amount of effort over time. And that distinction applies just for you, Mark. For all others here, I've apparently been able to address all manner of questions and comments. The alternative is that I will have to start ignoring all of your comments, Mark (which is a simple operation in the preferences dialogue) which I don't think is a good approach for either of us. I try hard to answer each person's questions on the forum, but when so many wide-of-the-mark questions and assertions keep occurring with regularity, I have to say that I personally tire of trying to address them in the threads that I've spent a fair amount of time compiling--for others. Chris

I do think you've got some issues with interpreting what you've got Mark, and your rationale for going the ways that you do with your MEH designs. This is not new. You may not know this, but perhaps half of the reason why I don't generally post at diyAudio anymore is due to history there with your approaches and methods (among a couple of others there). Without enumerating those things outright, I can say that they are fundamental differences in physics and psychophysics (i.e., how we hear). I don't believe that your fundamental viewpoints on this subject (if there are, in fact, any) come very close to those that I've developed over time measuring, experimenting with, and developing MEHs. I thought it easier to state this instead of trying to field your "questions that aren't questions". Thanks for being civil in your answers, but I don't believe that we're going to see eye-to-eye on this subject, i.e, MEH design and measurements, and I believe that you'll end up not thanking me if I start to enumerate the "why"--like you have beforehand on this forum, so I'll simply agree to disagree here. I recommend that you continue your efforts at diyAudio for those that have been convinced of your efforts there. I don't share your views on MEHs, and in fact have totally different viewpoints for your apparent issues that seem to drive your designs. I think it's best if we leave it at that. Thanks again. Chris

I didn't know about the customer resistance issue with the Jericho series (which really is a big step forward in commercial sound). But I'd wondered if that was the reason why that series hadn't taken over that market sector. Tom is an experimentalist (thank goodness) that first builds and measures the phenomenon before he lets the theory inform him of the "why". I think a lot of design nowadays is frozen in terms of innovation because we don't have more engineers like Tom. _____________________________________________________ If you take an SH-50 apart and measure each "way", with and without crossover networks, you get to see some things that are not commonly known. After doing that exercise with the SH-50 that I still own, I found some things that will never allow me to look at loudspeaker design the same way again. I'll not steal Tom's thunder, but I have to say that it isn't what many people think it is (i.e., the "Synergy" crossover filter design). It changed my outlook completely. Chris

It's 90 degrees of net phase lag on the lower frequency drivers that's induced for every order of the paired (high pass and low pass) crossover filters. If you remove the crossover filters and measure again, the lower frequency drivers will lead the higher frequency drivers in an MEH. You can see it in the spectrogram, step, group delay and phase plots for the loudspeaker. I think you're having trouble using these extremely high order filters having sharp cutoffs in MEHs, that absolutely don't need those kind of filters--because the reason for using them is simply not there as it is in multiple-aperture driver/horn loudspeakers. I'm not sure what you're doing using "time of flight", but I don't listen to my MEHs (or any loudspeaker for that matter) using single ways, turning off the other drivers. Chris

1) The Axi2050 needs PEQs to flatten its response on almost any horn that is straight-sided, etc. All drivers on straight-sided horns having controlled directivity need EQ--and this is just physics. 2) All "ways" in an MEH can actually use first order filters to time align the lower frequency drivers to the higher frequency drivers that are physically farther away from the listener. This is very different than typical multiple aperture (conventional) horn loudspeakers having separate horns and drivers, and direct radiating drivers in other non-horn-loaded loudspeakers, which benefit greatly from zeroth order filters in terms achieving better overall acoustic phase response flatness. 3) The Axi2050 driver is so robust in its design that unless you're using it at PA or higher SPLs, it doesn't need blocking capacitors, etc. to protect it. In fact, essentially all 2" compression drivers can take the full output of an amplifier (less than 50 watt/channel) without issues. [It's the little K-77 phenolic dome driver in the Klipsch Heritage series that has trouble taking more than 4 watts, that you really need to do a fast limiter on peak and integrated voltage levels using a DSP crossover.] Chris

I always try to EQ to flat response on-axis, given that diaphragm breakup is not occurring. What's likely in the case of Mitch's experience, he's probably used compression drivers with titanium or aluminum dome diaphragms that typically experience dome break up (i.e., non-pistonic modes) above 10 kHz, so he's probably accustomed to rolling this octave off. However, you paid real money for beryllium dome 2" compression drivers that don't do that. If you allow the response to roll off above 10 kHz, I think you're basically throwing away that investment: good response up to 17-20 kHz is what you paid for, and it adds back the "sparkle" and air that should be there. Notable drivers that also do not experience non-pistonic modes above 10 kHz are the ring radiators (i.e., BMS and certain B&C drivers), and the axi-periodic Celestion Axi2050 (titanium) diaphragm 2" compression driver, which was specifically designed so that it also avoids non-pistonic modes and cancellations above 10 kHz. These compression drivers also need to be EQed to flat response on-axis, since they don't "chatter". Chris

By the way, I just thought of this, and I think it should be laid out here: If using multiway loudspeakers having separate drivers/horns, typically the mouth of the horn or the front face of the driver (for direct radiating loudspeakers) is clamped to the front baffle of the loudspeaker, thus inducing a physical misalignment of the drivers' acoustic centers, with the higher frequency drivers typically leading the lower frequency drivers in terms of their time alignment. These loudspeakers need digital delay added to their DSP channels to time align them to the lower frequency drivers. In the case of the multiple entry horn (MEH), the physical alignment of the drivers has the lower frequency drivers mounted in front (closer to the listener's ear) than the higher frequency drivers: So, if a zeroth order crossover filter is used, it will allow the lower frequency drivers to lead the higher frequency drivers by 1/4 wavelength at crossover (90 degrees). While this is acceptable for an MEH time alignment, it will actually be a little closer if a first order filter is used to delay the lower frequency drivers by 90 degrees, thereby achieving time alignment without having to "cut and try" the channel delay corrections. So bottom line: You actually need something in the lower frequency driver channel(s) to delay them in an MEH, albeit very slightly. Just using a first order set of crossover filters (low pass on the lower frequency drivers and high pass on the higher frequency driver[s]) is actually desirable. I've used just straight delay on the lower frequency driver of the K-402-MEH (equivalent to 90 degrees at the crossover frequency) and alternatively, just simple straight first order filters without digital channel delay, and could see no difference in the output of the MEH. JMTC. Chris

Good luck. It appears that you've actually got room dimension issues, and not so much electronics problems. The amplifiers in the Onkyo may produce a bit lifeless sound (it having class D amplifiers). Using the pre-outs of the Onkyo to perhaps class AB or even better, class A amplifiers, might change the harsh sound a bit, but probably not the to degree that you're expecting/wanting. Other than that, I've found the room is about 50-70% of the equation, and the loudspeakers themselves are most of the balance. Electronics are much less of a factor than most would like to believe in my experience once you get to the best-performing horn loaded loudspeakers. You can work on the Cornwalls a bit to time align the tweeter to midrange a bit better, i.e., no one has posted a spectrogram, step response, phase or group delay response on the Cornwall IVs yet--at least not that I've seen--so the amount of improvement available in time alignment isn't really known, but I'd guess that it would match or beat any improvements in the absorption of early reflections in-room. But since the loudspeakers are brand new, most try to ignore those type of suggestions. The efficiency of the Cornwalls means (according to Klipsch's law) that the modulation distortion is quite a bit lower than other direct radiating loudspeakers, and a lot of what you hear with the Cornwall IV sound is due to that, and directivity from ~800-1700 Hz. You might have a little better luck if you try La Scala IIs in that room, but if you're listening to pop/rock only, then you'd give up about an octave of deep bass response in-room with the La Scala IIs, which a subwoofer would make up. Chris

This hasn't been my experience. It's been my experience, however, that the sources of information of how to set up a proper acoustically balanced home theater are not good for loudspeakers have such good directivity control as Klipsch Heritage/Jubilees, etc. I found there is a great deal of difference between direct radiating loudspeakers and fully horn loaded, and the acoustic treatments follow suit. Can you describe what this was (brands, models, room dimensions, treatments, etc.)? The 1990s was before the current era of home cinema--things have changed quite a bit since then. It may be too large for the room, i.e., too much absorption, unless you can fold it up a bit to adjust the total absorption surface area. Also, the comment about toeing in the speakers and putting something on the side walls is probably 2x to 10x more effective than just covering the center screen and gear. Covering the electronics cabinet will probably permit you to toe in the loudspeakers (as I mentioned above) that you probably find that you can't toe-in now because of those early reflections from all the stuff between the loudspeakers. That's not a large listening room horizontally and vertically, so acoustic treatments can only do so much in my experience. In general, you'll find that the room is going to sound a bit dead if the acoustics are optimized for that room, due to its volume and the limitations of the shorter reflection times from side walls, ceiling and rear wall. Directivity can only do so much before the those side wall and rear wall reflections become dominant, and the only alternative is using a great deal of good diffusion panels, but that tends to cost a lot more than absorption. Chris

Well, it depends. Lets take the loudspeakers first. In my listening room, using K-402s on top of KPT-KHJ-LF bass bins, and noting that my flat screen is above the mantle between the Jubilees, when I place Auralex Sonofiber absorption tiles across the screen, the center image subjectively moves downward to be more in-line with the K-402 axes--by at least 6 inches. When I place absorption material across the center K-402-MEH (a K-402 horn that's a full range loudspeaker) which is directly in-line with the left-right K-402s, I get a more defined phantom center image, but then I note that the issue with the "2 kHz fundamental flaw of stereo" subjective dip in response seems to increase (i.e., there are less reflections filling in the perceptual hole at 2 kHz that correspond to the interaural distance between eardrums, explained in the following figure: So...in your case, I'd also put a cover over the center electronics cabinet and gear--probably two blankets thickness, as well as covering the flat screen as you have above, then listen using something like your best female vocalist recording at medium SPL (about 75-83 dB at the listening position). You should hear a stronger phantom center image, but the room will sound a little bit smaller, and the sound quality might tend to be a little "thinner". You can now toe-in your Cornwalls toward the listening position. Secondly, I don't know if you've looked at the front of a Cornwall with the grill off. There is a lot of flat area there--something that companies like B&W and the older Acoustic Research (AR) used to cover with acoustic absorption material. I'd at least try putting absorption across the top of the Cornwalls, but that might not be enough--and you might hear even more difference if you cover the areas on either side of the tweeter and midrange horn with some absorption material (YMMV). Try it--it doesn't take much. You can let two ends of a quilt or blanket cover the top of the Cornwall and hang down on either side of the tweeter and midrange horn mouths. Adjust the amount to taste. You can also experiment with adding throw rugs in front of the Cornwalls to decrease the level of floor bounce from the current case using the thin carpet you now use. Add and subtract absorption--and use your best, highest quality acoustic-only recordings. I think it will become pretty obvious what differences there are (if any) that you like. JMTC... Chris

Done.

Yes...