Al Klappenberger

Shawn, YES! That is the last word in subjective testing. I doubt it's ever going to be done to help resolve the age-old capacitor contrivance though. It would require a very fancy switch to swap out every cap in a crossover network at once. Evan to swap out two complete networks built with two different brands of caps would require a 4 pole two position relay, one for each channel! It could be done, but I bet it never will be! That's too bad too. I would really like to see it. AL K.

That thing is really neat! I have never injured myself on a table saw probably because I am scared to death of it! It takes only an instantaneous slip to loose fingers though! I would normally be skeptical of that sort of thing figuring that it would have to be so sensitive that it would be stopping itself at regular intervals for no reason. That sort of thing could CAUSE accidents. The video clearly shows the break destroying itself when it stops, so it clearly must not be activating without good cause. I'm impressed! AL K.

Mark, It is entirely possible that if you can't measure the difference between to things and you can hear a difference, you are simply measuring the wrong thing! One of the beauties of instrument measurements is that they are extremely focused on one single parameter. The usual reason though is that it is EXTREMELY easy to fool ones self with listening tests. The human brain will very often hear what it expects to hear. No one is immune to this. Even though I am aware of it, I often fool myself as well. This is one of the main reasons I seldom express my opinion about how something sounds. I believe that only a blind A / B switch test where someone else flips the switch is an actual valid test. Even then it's only one set of ears. Al K.

Ok.. You will not report me, so I just reported you for destroying this thread. Al K.

MechMan, That speaker sure rattles my listening room! I suppose it would depend on what you want the sub to do though. If you already have a K24 sitting around, what have you got to loose? Al K.

Geof, I did something similar. I put a K24 driver (of the Heresy II) into a ported box and paired it with a K55V and Beyma CP09 tweeter high end to make a set of speakers for my den / home theater. I found that it extended solidly down to 30 Hz. I would need to be driven by a mono amp and is rather large. It's the bottom half of the speaker in the picture. Al K.

Mr. pseudo-moderator, I see your ignorance has no bounds! No arms were removed, nor was I! I might also point out that this thread has nothing to do with filters. I suppose you did not notice that fact! And again. If you got a gripe and believe that it is your self appointed responsibility to protect this forum form anyone who YOU feel is abusing it, take it to the moderators. Or maybe you think they are unable moderate it without your help. You might also re-read the "sticky" you sited at the top of this forum which says: On a related note: If you are running a business by restoring/modifying/upgrading, we do not mind you assisting others or chiming in on audio topics as long as you are not directly soliciting sales. I will have nothing more to say about this. TAKE IT TO Amy! I DARE YOU TO DO THAT! ---------------- Fastslappy, I does seem that this thread is being stolen, but I think the initial question was answered quite nicely by Bob Crites. That is not an excuse though. There isn't much more I can add since I only have one of the horns he wanted to know about sitting here. Al k.

AH! G O L D ! GIMME, GIMME!! Al K.

Marion, Read my signature note... Al K

Marion, I too believe in patronizing U.S. made goods, but consider that Klipsch allows every idea discussed on this site to proceed to its natural and logical conclusion. If this had not shown itself to be in their best interest they would have pulled the plug on it long ago! Realize too that people who start out building stuff themselves will often wind up buying a finished item after they discover what they are trying to do isn't as easy as they initially though. Then there are those who already have older items and realize through discussing here that progress has moved on and will want new. Another camp are those who simply want to guild their lily. That can lead in all sorest of directions! Al k.

G, I missed the point too! I only tested the 220 on the one stock horn, but here it is on Dave's FastTrac clone of my 1-inch Trachorn. I don't suggest that it should be used as a 2-way driver but it sure looks like it could do it! I suspect it couldn't handle power cleanly down low in frequency. Al K.

G, Here's the intermodulation distortion plot on the Selenium D220Ti and HM17-25 horn. The levels are 100 dB SPL at 2 feet. That's a VERY high level. The worst distortion product is over 30 dB down. That's VERY good! Al K.

G, I have done several frequency response test on the Selenium D220Ti and HM17-25 horn. I did one comparing it directly to a T35 (black trace) on the same plot. The vertical scale is 10 dB / division. That's below. I think it's one of the best for extended range and low distortion. I have also done some testing just a few days ago on a larger horn. Its response looked just as good on the larger horn. AL K.

If you have compared them directly to a similar tweeter from JBL, then my slot theory is out the window! The little round aperture of the JBL 2404 and Beyma CP25 both did the same thing at high level. If a slot was the cause it would have sounded the same way no matter the brand. That mystery will just have to remain for another day! Al K.

"I recently purchesed a set of Beyma tweeters (CP 21's) from you which you described as "not as good as the CP25's but still very good". In my opinion they were complete rubbish & I sold them straight away....the Crites 125's fitted with Baby cheeks flares blew them out of the water." That's interesting. That's one tweeter I have been interested in myself. I suspect that the reason you rejected it is because of the slot it's based on. A slot is used in constant directionality horns to get dispersion. They have a reputation of sounding like a "frying pan". That, of course, is another one of those universal pseudo-descriptive terms like "smooth" and "silky" that relay mean nothing. "Silky" is one that was often used to describe ionic tweeters that generate intermodulation distortion like crazy! I would love to put a set of tones through a CP 21 just see if that is what is what you were hearing. I found that the small aperture hole in the CP25 and JBL 2404 caused distortion if you ran them up too loud. I suspect it might be the same thing going on. Al K.

Sankar (Gram), I can't comment on the recording techniques discussion because I know so little about it, but one thing I will go along with totally is the suggestion about headphones. This is my standard to fall back on when questions about effects added by speakers or crossovers are raised. Sibilance, for example (the sss sound often heard on some vocals). It has been blamed on ringing in crossover filters. Headphone listening shows the sibilance is still there and part of the recording! Sarah Britmen has a HUGE case of it! I use a set of Grado SR225: http://www.gradolabs.com/product_pages/sr225.htm They are not extremely expensive. They sounded a lot better to me than my "stock" Belles did. Now that I have done a lot of upgrades to them the sound is very similar. I don't think they are very comfortable though. Al K.

Gram, You have identified a question I have also considered. My solution is simply to make a plot of the entire range of the driver and look at the area of interest! I usually ignore published specifications. There is also the question of where to take the measurement. Do you do it at 1 meter from the mouth of the horn or 1 meter from the driver. After all, the horn mouth is what lines up with the front of the speaker, but horns are all different lengths! What distance do you call the standard? This is one reason I quit making the original network I designed for the Cornwall. It had no way to adjust the level of the drivers. I actually have to agree with Dr. WHO on this one. Al K.

Lee's comments really illustrate the complications involved in recording and mixing. As an example, Lee set me a CD of one of his recording of a Mendelson symphony. It was a very good sounding recording, but had one flaw. As a live recording, the conductor made a few comments about the work before the orchestra began to play. You could hardly hear him on the recording! What should the recording engineer do to fix this next time? Should he move the mikes? Should he provide a separate mike just for him? Should he have the conductor dub the comments in after the recording was made? There is a lot more to this than you might think! Al K.

Roberts, You should try listening to LIVE music sometime. How else can you know what it sounds like? Have you ever owned Belles? You sell horns to Belle owners! Al K.

Roberts, I have calibration data on all my instrument microphones. Do you have calibration data on your ears? I strongly suggest that you see a hearing specialist to check your hearing. Extremely loud sounds such as hand sanders, joiners and power saws will damage a person hearing over time. You value and use you hearing so often to give us your expert opinion on so may audio innovations that you certainly should take care of it and monitor it's health! Al K.

Roberts, Your remaining stock of unsold networks is not relevant. The presence of my name on your web site represents an affiliation that no longer exists as of the time you paid off the royalties for the remainder. This act, along with your verbal declaration to terminate the agreement, dissolved the relationship. I will no longer tolerate any inference that there is ANY form of relationship remaining. For the FORTH TIME: REMOVE the name ALK Engineering from your web site! The very fact that you initially paid the royalties for each network as you sold them, then paid off the rest in a lump payment after terminating the agreement is clear evidence you were serious about ending the relationship. Now that you have paid off the royalties in full, removing any incentive I may have had to help you sell them, you insist on using my good name and reputation by inference to do it! I will not sanction your jury-rig networks directly or by inference. AGAIN: REMOVE MY NAME FROM YOUR WEB SITE! I will make a final point clear. I still grant you the right to sell the remaining stock, withOUT any modifications. This is all that remains of the agreement. NOTHING MORE. AL K.

Roberts, "All it takes is a couple of little changes and they are no longer your design. " Once you start screwing around with crossovers, a subject you know NOTHING about, you associate ALK Engineering with your imperial jurey-rigs. They are truly NO longer my designs by your own admition! For the THIRD TIME: Remove ALK Engineering from the menus on your web site! As long as that remains, the implication is that you are associated with me. You are NOT! Al K.

Shawn, Yes, I am generating the center channel by simply mixing left and right with a resistor network PWK style. It's the only way I have to do it. All the recordings I have are simple CDs and other standard 2-channel sources. I have found though that I really don't need a center channel. I have it turned way down. The extreme slope networks just don't need it for stereo program material. My earlier comment about the headphones got me to pull out my set of Grado headphones. They are a middle of the line quality set but still sounded a lot better than my Belles when they were "stock". That's one of the reasons I started fooling around with speaker upgrades in the first place. Anyhow, I just did some listening with the headphones on stereo stuff switching back and forth to mono. This really illustrates what's going on. A set of headphones have no crossover network, no comb effects with only a single "driver" to each ear totally isolated from each other. Your ear / brain combination is doing everything. On mono, everything is squarely in the middle of your head. If you move the pre-amp balance control to one side it's like somebody hooked a vacuum cleaner to one ear. It actually FEELS suffocated! I doubt two speakers in a room could ever focus a mono program squarely in the middle like that! Al K

Here's a few more thoughts about playing mono programs on a stereo system that shows major comb effects. In the old mono days, everybody had only a single speaker. The sound came only from one place and every component of the program, that is the piano, the flute and the bass drum, for example. All came nicely from the single speaker. That same program, when plaid on modern two channel speaker system, should still seem to come from exactly the middle of the two speakers. Every component should seem to come from the same place. Square in the middle. I think a speaker system that generates major comb related peaks and dips will reproduce the components of the program at random places between the speakers. One that does not will tend more to focus the mono program right in the middle. This might not be as much fun to listen to, but it would be more "correct". This implies that playing mono programs through a stereo would be a very GOOD way to test it's stereo image. The more stuff sits in the middle the better it will reproduce a stereo image when it gets a stereo program. The comb effects will generate the artificial ambiance a lot of people like with gentle slope networks. This would render a good stereo system with a good stereo image rather boring for mono programs! AL K. EDIT: I just realized something else. My speakers are 18 feet apart. A mono program seems to be 18 feet wide with most of it seeming to originate from the middle. I suppose that's just how it has to be with more than one speaker. Just now focused can the center get when reproducing mono programing from more than one speaker? I could turn up the center channel volume, but that would screw up the stereo image big-time! I suppose stereo headphones might be one way. They give you the impression everything is right in the middle and inside of your head!

PSG, Listening to mono programing over a two channel system is an interesting special case. The comb "distortion" of a stereo image when there is no stereo "information" in the program is not really relevant. There is no stereo image! If everything was perfect, a program that was actually recorded with a single mike would come out of the center and remain in the center no matter where you were sitting in you listening room. With serious comb interference patters in the room literally anything could happen to the location of where the program would seem to be coming from. You need to walk around the room to tell.You also would need to do this with gentle slope networks and again with steep slope networks to see the difference. Not may people will bother! I did a bit of listening to a distant FM station last night where the signal was randomly switching from stereo to mono. I found that it was hard to tell when it changed without looking at the stereo light on the tuner. The noise level was not very high to confuse the issue either. It's another case of the subjective nature of listening tests. Another factor is the way modern recording engineers mix their many tracks from multiple microphones down to two tracks. I can only assume that mono recordings from years ago were also mixed down from multiple microphones. It's just another confusion factor! I have a copy of articles in the Klipsch bibliography they used to make available. There is a lot of research on this titled "Symposium on Audio Perspective". It's been years since I looked at it, but it all seem to assume only two microphones and a derived center channel versus three discreet microphones and channels. I suspect multiple mikes mixed down to one or two as is done these days would really screw up the results no matter how good the speaker system was. AL K.