3dzapper Posted November 24, 2003 Share Posted November 24, 2003 For some reason these "new" AAs are sounding very "hot". Even more so with the 1mF bridge. Here is the second configuration I am trying now. Rick Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 24, 2003 Share Posted November 24, 2003 For some reason these "new" AAs are sounding very "hot". Even more so with the 1mF bridge. Here is the second configuration I am trying now. Rick Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 24, 2003 Share Posted November 24, 2003 Rick, There is good reason they may sound hot. This bridging mod and the lower loss Hovland caps casue the tweeter to receive more energyue to lower loss. This is only a good thing if your system and listening room needs more highs. If not, you would probably be among the people who like the old Alnico K77 tweeter and/or paper in oil caps. These changes could be doing for you what a low loss tweeter filter plus a "L" pad would do without the nice adjustment an adjustable L pad could give you! This mod does NOT correct the entire network, it just reduces the missmatch casued by the poorly designed tweeter filter and adds a stopband notch. This moves it toward the so-called "elliptic filter" of the later Klipsch networks (like the AL-3, AK-2, AK-3, AB-2, AB-3, to name a few). The tweeter filters in these are very similar to the high filter in the new ES600 extreme-slope network I just posted a few days ago. Half of it anyhow! Al K. Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 24, 2003 Share Posted November 24, 2003 Al, "This moves it toward the so-called "elliptic filter" of the later Klipsch networks (like the AL-3, AK-2, AK-3, AB-2, AB-3, to name a few)." How steep were the initial drop off in these filters? Shawn Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 24, 2003 Share Posted November 24, 2003 This configuration with the poly caps is much better. The output from the tweeter is a few db higher than the squaker when measured at the mouths of the horns with music. Tomorrow I think I'll switch the K77s with the Heresys agian. I put the mud magnet K77s in the horns to juice up the highs a couple of months ago. This should even out the sound perfectly until I can get my ALKs built. That won't be until after hunting season and Christmas though. This mod takes out a PITA blare in a trumphet that has bugged me for twenty-five years. Thanks Al. It must have been that 3500khz bump at the K77 Fs that John Warren plotted a few weeks ago. The slope of the graph you posted eliminates that bugger. Rick Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 24, 2003 Share Posted November 24, 2003 Shawn, You weren't supposed to ask that question! The fact is that everybody with one of those networks I listed earlier has been listening to an extreme-slope tweeter filter all along! I just haven't mentioned it before! The filter (by computer analysis) cuts off at 5973 Hz and reaches "arc top" level of 23 dB at 5216 Hz. This is a ratio of 1.15:1 (very sharp) and represents 138 dB / Octave and is equivalent to a 23 rd order Butterworth filter over that segment! The fact is, it even used a trick of choosing the passband ripple during the synthesys to casue an output cap that goes through a huge value to a negative value. This allows it to be totally removed from the filter as it passes through infinite value! My ES600 does the exact same thing! I really wonder who at Klipsch desinged that filter! BTW, if you do a search, you might find where I reverse engineered it and posted the results on the board. The title was something like "Clip the elliptic filter - maybe not", or somethig like that. I don't remember. Al K. Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 24, 2003 Share Posted November 24, 2003 Al, Opps, sorry. Curiosity got the best of me. That is pretty forward thinking of Klipsch in those networks, I hadn't realized anyone but Joseph/JSE had done anything like this in a commercial product. On those networks did the squaker have a low pass and if so was it also elliptic? Thanks, Shawn Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 24, 2003 Share Posted November 24, 2003 Shawn, NO! That's why the impedance is not constant. To be constant impedance the filter in each crossover pair (highpass and lowpass) need to have nearly the same slope. This is so the reqctance slopes of each filter are equal and opposite at thier inputs, thus, the reactance canceles out leaving pure resistive impedance. The Klipsch networks I listed only go half way. Only the tweeter filter is extreme-slope. The squawker filters are just a single cap, or a cap and an inductor (N=1 or N=2) at the crossover. You can add to that the rolloff of the squawker driver. In addition, the large inductance of the autoformer begins to act as one exta element way down low. This helps keep deep woofer frequencies off the squawker. Al K. Quote Link to comment Share on other sites More sharing options...
sfogg Posted November 24, 2003 Share Posted November 24, 2003 Al, Gotcha, so listening to those networks really wouldn't be the same as hearing a matched (hi/low pass) extreme slope crossover. Thanks, Shawn Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 24, 2003 Share Posted November 24, 2003 Shawn, No. The ES600 has a very narrow band at the crossover where both driver are operating. Both filters are equally sharp. The tweeter filter shuts off the squawker range quickly but the squawker is still sloping off slowly widening the interference band. It's only half way there. Al K. Quote Link to comment Share on other sites More sharing options...
3dzapper Posted November 25, 2003 Share Posted November 25, 2003 I can't wipe the smile off my face. I finished swapping the mud and alnico tweeters about an hour ago. While listening to a CD I made of Aker Bilt(sp?) an involuntary smile, broad grin really, crept across my face. As he played his sax the drummer was ticking the cymbals with a brush. The stroke and swirl were perfect and when he stroked a little harder to hit the base of the brush, just right! I just mught keep these Klipschorns. (Ha Ha) Rick Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 25, 2003 Share Posted November 25, 2003 Rick, Good deal! Al K. Quote Link to comment Share on other sites More sharing options...
ben. Posted November 25, 2003 Share Posted November 25, 2003 I've started another thread (Scratch Built Type A), in which I ask a few general questions regarding component choices. I realize that many of you have chosen another route design-wise, but if any of you have a moment, I'd appreciate any opinions you may have. Thanks, Ben Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted November 27, 2003 Share Posted November 27, 2003 Guys, I mentioned earlier about the "elliptic filter" in the Klipsch AB, AK and AL sereis networks. Here is a plot of the tweeter filter in the AB compared to the AA with the 1.0 uF bridging cap. As you can see, the Klipsch "elliptic" is very good. Al K. Quote Link to comment Share on other sites More sharing options...
cwm Posted December 1, 2003 Share Posted December 1, 2003 All this information is very good and useful, but I would still like to know if anyone has tried "Different's" .01mfd bypass and if so how did it sound? Perhaps "Different" could give us a report? I think I will invest in a premium grade 1.0 mfd cap and see what occurs with my AA type LaScalas as per Al's suggestion. I'm still trying to "bull" through the calculations provided---------- Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted December 1, 2003 Share Posted December 1, 2003 CWM, I did try the .01 uF cap in one of the curves. I think you will find that you could just bearly hear a difference with that value. GO FOR THE BURN MAN! Use the 1.0 uFd! AL K. Quote Link to comment Share on other sites More sharing options...
Benesesso Posted December 8, 2003 Share Posted December 8, 2003 OK, so what do I do to a pair of AA's that I just converted to A's? Benesesso Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted December 8, 2003 Share Posted December 8, 2003 Benesesso, Easy, re-convert them back to "AA"s and add the bridging cap! There's no way to do this trick to the "A". Al K. Quote Link to comment Share on other sites More sharing options...
Benesesso Posted December 8, 2003 Share Posted December 8, 2003 OK. I'm right in the middle of returning to the 4-0 taps from the 3-0. But what config. will sound "better"-AA w/this cap., or the A with it's more power-to-the-tweeter than the AA-at least until I get yours? Benesesso? Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted December 8, 2003 Share Posted December 8, 2003 Benesesso, Yes, you will get more energy to the tweeter with the bridge cap on the "AA" than without it. The "A" filter (a single cap) will probably be more yet, but at the expense of tweeter protection and the interaction between driver a slow slope causes. AL K. Quote Link to comment Share on other sites More sharing options...
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