BEC

It is fun to play with different tops on the MWM. This top is an EV Varipex that I used for several years on mine. The Variplex takes over at 300hz for midbass and the cross to the tweet is at 1200hz. A few watts will get this rig so loud that it is scary.

I think that top might keep up all right with a single woofer MWM bin. Probably not with a double woofer set of bins. I have seen a professional installation in a Church that used 4 MWMs bins and 5 Lascala tops. Bob Crites

Here is another one that is fun to watch and listen to. http://vimeo.com/43426940

"how do you reconcile your earlier assertion that Klipsch went to low ESR caps in the 70s with the fact that even now, Klipsch is still using relatively high ESR Mylars" I of course don't have a lot of experience with the newer Heritage crossovers. I did, just for fun, test some of the caps in an AK-4 a few years back. I saw pretty good ESR reading on all of them. Somewhere around 0.05 ohms ESR for the large value ones and around 0.1 for the smaller ones.

"I doubt very much that Klipsch measured every capacitor they used" That is probably correct. According to Jim Harris in the 1989 "Speaker Builder" interview, Klipsch used a PC to check each crossover and another PC to check each speakers output. I think I have read somewhere about a "crossover tester" from the earlier days before the PC.

Now to elaborate a bit on this, notice that Paul talked about the ESR being "low enough". Notice also he did not mention the perils of getting ESR too low. I don't think he overlooked that. He would have liked to find ESR so low as not to be even measurable. Why? Because ESR is bad, something we do not want, something to be minimized. I have tested enough of the old Klipsch film in oil caps to know that at least by the 70s Klipsch used very low ESR caps. Most are over 1/2 ohm by now, but sometimes I find one that tests down to around 0.1 ohm. So, I infer from that the likelyhood of all of them being better than 0.1 ohms ESR when Klipsch installed them. I can't think of the mechanism that would cause ESR to lower with age.

"So Bob, what do you think the average original ESR numbers might have been for all of those various mylar caps PK was using? Do you think they were the same as a new tightly wound polypropylene film type? Don't we almost know for certain that the caps he used were already a decade old or older before he even started using them? How can we claim to be restoring these speakers back "to their original sound", when we know the original insertion losses were much higher, and certainly would have effected the sonic signature of the speaker." Let's take this easy part and answer it first, or rather, let's let Paul answer it.

MWMs also make good work benches.

Yes, I am old, but if you get rested enough, we can go around again. Fortunately the laws of physics have not changed since last time, so I can just refer you to my previous position.

Dean, I thought we got your mind right on caps?

My measurement is at 1 meter also. Bob

It is always a combination of driver and horn. Not every driver performs as well on every horn. I could show lots of examples where there was a horn I wanted to use with a certain driver that just would not work with that horn. But, there would be another horn that the driver worked well with and another driver worked well on that horn. You can bet that when Radian tested their driver for their published curve, they matched it up with a compatible horn. Bob

Here is a Faital HF-200 on the Eliptrac horn. Bob Crites

Remind me which driver was that? I used the Faital HF-200 driver.

I am not sure I would have ever gotten happy with the Jubilees without going to a passive crossover and going to an HF driver that does not require so much EQ on the K-402 horn.

If that is the K-500 horn, yes, I am interested. Bob Crites

Here is something that people needing bi-focals might consider. I have used this for 20 years and this is the only way I would want to go with correcting vision. This might not be for everyone, but it took me less than one day trying it to be sure it was the best for me. http://www.allaboutvision.com/contacts/monovision.htm

Neil, You can connect the T2A like the crude drawing below. Shown is the connection for 3db of attenuation. Moving the 2uF cap to tap 3 would give you 6db of attenuation. Tap 2 is 9db and tap 1 is 12db. The cap at the input of the T2A is just a large value to allow all frequencies to pass but block any DC that might come from the amp. Just a safety feature in other words. For experimentation, not left unattended, you could leave out that cap. Bob Crites

Well, you could try higher, but at 600hz, you would lose another 5db or so of output. I think the resultant plot would be better crossing at 500hz if your driver can handle it. Here is the full range plot I got with the network I built.Bob Crites

I think that plot was with the MWM sitting out in the middle of my shop floor. I was not interested at the time in trying to look at the lower frequencies, just seeing where to cross to the HF. I decided on 500 hz. for the crossover frequency with the K-402 and Faital HF200. Bob Crites

Here is a plot I did a few years ago. Bob Crites

I do not have those Heresys. They belong to a forum member and former Klipsch employee Andy Barr. I think that he just put a piece of mesh between the woofer and motorboard. His forum handle is HDBRbuilder. He might come along and comment for us. Bob Crites

Here is a good idea. Bob Crites

Congrats !! We are experimenting with different caps. With this light blue one, he is perhaps a bit too mellow. Bob Crites

I am happy to announce the arrival of Levi Dain Crites. Born at 9:32 PM on Dec 4, 2012. Weighing in at 7 pounds 12 ounces. Baby Levi, mom Amy and dad Michael Crites are all doing fine. Grandpa Crites is a bit tired this morning. Bob Crites