geoff. Posted June 21, 2019 Share Posted June 21, 2019 I am currently using an AA crossover (in bad need of a recap) with the CT-120’s in my LSI Splits. I love the highs and the mids. I swapped the stock K-43’s for K-33’s to get the bass significantly lower at “normal” listening decibels. The Kappa 15C’s went into another project (2-way Peavey FH1 with K-510), but would take these LSI Splits to another level. Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted June 21, 2019 Share Posted June 21, 2019 After revisiting this, I am tempted to put a spare pair of 15C in my splits.....I have been looking for another project.... Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted June 21, 2019 Share Posted June 21, 2019 When you guys are swapping out the K-33 and replacing it with the Kappa 15C, are you also adjusting which tap is being used on the autoformer in the crossover (which, in turn, may require an adjustment on the capacitor values)? I am wondering (out loud) whether the preferences being expressed are an outcome of the "bass boost" (due to the greater efficiency of the Kappa 15C). Quote Link to comment Share on other sites More sharing options...
geoff. Posted June 21, 2019 Share Posted June 21, 2019 Using the stock crossover the increase in bass output at all levels, even more so the mid bass segueing nicely to the squaker, is the desired effect. Who on earth would not want more available bass, all things being equal? 1 Quote Link to comment Share on other sites More sharing options...
Heritage_Head Posted June 21, 2019 Share Posted June 21, 2019 15 minutes ago, geoff. said: Using the stock crossover the increase in bass output at all levels, even more so the mid bass segueing nicely to the squaker, is the desired effect. Who on earth would not want more available bass, all things being equal? Quote Link to comment Share on other sites More sharing options...
Deang Posted June 21, 2019 Share Posted June 21, 2019 Tweakers: I got the sound I want. Meter Readers: You ruined your perfectly engineered system - you should have bought an equalizer. 1 Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted June 21, 2019 Share Posted June 21, 2019 1 hour ago, Deang said: Tweakers: I got the sound I want. Meter Readers: You ruined your perfectly engineered system - you should have bought an equalizer. Perfect. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 5 hours ago, Deang said: The one piece phase plug K-55 is pretty much out of gas at 4.5kHz. The K-400 puts enough squeeze on the signal to get it to 6kHz. With a better tweeter like the de-120, you can lower the crossover point, and get the K-55 operating in the area it was designed to run. It also unloads some energy off of the K-400, which helps it not go into distress at live listening levels. The downside is the sound becomes a bit tweeter heavy - the tweeter often seems to dominate the sonic signature. Some like it and some don't - it's completely subjective. On paper it makes sense. In practical usage - it's hit or miss. This is in the context of a first order filter, not with the steeper slopes that Roy is using. A better solution is to run the the two piece phase plug version of the K-55 (or A-55-G), and the AA. At least, this is what I prefer. In a LaScala or, especially, in a Cornwall, one can fit DaveA's larger MAHL with the superior, and less expensive B&C DE-10 driver, which can cross over as low as 2 Khz with a high order slope. So one can use a plain, older K55 and simply choke off the top end (thereby reducing the 9 Khz. peak that rears it's ugly head) without having to upgrade to a dual phase plug driver. Personally, I would choose a Xover point that matches the POLARS closely between the two, but that's beyond the scope of this text. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 3 hours ago, geoff. said: The first thing I experimented with in my ‘92 LaScalas, based on the experiences of other forum members, was the Kappa 15C. If I had to sum the immediately noticeable effect up in one word without hyperbole it would be “supercharged”. “Bionic” just came to mind too, lol. Everything you have read about this woofer is true. Thanks for pointing this out. I'm pretty sure I"m the guy who started all this. Simply put, the actual response it crisper in the MIDRANGE with that driver in a LaScala and also give much tighter, more defined bass in a Quarter Pie. I tried the EVM 15L, the K33, and finally the Kappa 15C in the QPie and it won the listening tests. End of quest. Tromprof can probably fill you in as the "King of the Quarter Pies" and I'm pretty sure he tried all the woofers I mentioned and ended up with the Kappas. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 14 hours ago, Dave A said: Sadly nothing. Claude and I are both suddenly very busy so I have just loafed along with what I have for now and not done anything more. I will get around to it some day soon perhaps. I still have a Super Cornwall and Super Heresy projects on hold, so you are right. I'm UnRetired. LOL. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 3 hours ago, jimjimbo said: My splits have K43's, but I rebuilt the networks with some really nice caps. I did install the CT120 and A55G in them, and they rock. Currently running a restored Fisher 500C with the splits and a pair of Heresy Industrials at the same time, and it is magic. Have had several folks comment that they thought it was my best overall sounding system, and sometimes depending on my mood, I would agree..... Does alcohol consumption or other mood altering substance also come into play here? LOL. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 3 hours ago, jimjimbo said: After revisiting this, I am tempted to put a spare pair of 15C in my splits.....I have been looking for another project.... Easy enough. I'd like to read about your conclusion after, since it was K43's that eventually led me to to recommend 15C's as a cheaper alternative with similar sonic benefits in the midrange detail without sacrificing any bass, like the K43 did. Quote Link to comment Share on other sites More sharing options...
ClaudeJ1 Posted June 21, 2019 Share Posted June 21, 2019 3 hours ago, PrestonTom said: When you guys are swapping out the K-33 and replacing it with the Kappa 15C, are you also adjusting which tap is being used on the autoformer in the crossover (which, in turn, may require an adjustment on the capacitor values)? I am wondering (out loud) whether the preferences being expressed are an outcome of the "bass boost" (due to the greater efficiency of the Kappa 15C). It's a direct swap with no modifications. Like I said, the main benefit is in the midrange and doesn't sacrifice as much bass as the K43. It's like a "tweener" driver right between the 33 and 43. See the data below. Kappa 15C in Black, K33 in Gray. The one at the very bottom compares the 15C Black to the K43 in Gray. Since out hearing is more sensitive in the MIDRANGE, the 15C beats both the K43 and K33 as you can see from the curves. Quote Link to comment Share on other sites More sharing options...
RRR Posted June 21, 2019 Share Posted June 21, 2019 On 6/19/2019 at 6:29 PM, PrestonTom said: Jason, the Kappa 15 C may be a fine driver ... I don't know. These things are designed as a system. There are certain specs on the driver relating to its electrical and mechanical properties (VAS, Qts, efficiency etc). These in turn will guide (not dictate) how the engineer can "tilt" the spectrum of the system (driver inside a horn loaded box and integrated with other drivers). My point, which seems to be lost on others, is that when you change drivers, you may want to change the geometry of the horn throat, the back volume behind the driver and the crossover etc . The issue is design and NOT mix & match. I have no doubt that your system "sounded different" after your modifications. However, I remain skeptical that it sounded more accurate. Can we agree to disagree? Have you tried using the woofer in your La Scala's ? Measured it ? Spent time listening to it ? I have and gave my honest opinion, take it or leave it. 1 Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted June 21, 2019 Share Posted June 21, 2019 7 hours ago, ClaudeJ1 said: It's a direct swap with no modifications. Like I said, the main benefit is in the midrange and doesn't sacrifice as much bass as the K43. It's like a "tweener" driver right between the 33 and 43. See the data below. Kappa 15C in Black, K33 in Gray. The one at the very bottom compares the 15C Black to the K43 in Gray. Since out hearing is more sensitive in the MIDRANGE, the 15C beats both the K43 and K33 as you can see from the curves. Claude, this is an interesting simulation. I assume it is for a LaScala cabinet. Certainly, it allows one to raise the crossover point a little and save the midrange from having to go so low. It might even help getting the crossover to a region where the polar dispersion is more similar. Quote Link to comment Share on other sites More sharing options...
Marvel Posted June 21, 2019 Share Posted June 21, 2019 8 hours ago, ClaudeJ1 said: Personally, I would choose a Xover point that matches the POLARS closely between the two, but that's beyond the scope of this text. I think this is often overlooked by folks swapping things around. Dennis had pointed that out a long time ago as well, where a manufacturer (I can't remember who at this point) had what seemed an odd crossover point between the woofer and mid horn, but it was done so the polars matched between the two. Bruce Quote Link to comment Share on other sites More sharing options...
WillyBob Posted June 21, 2019 Share Posted June 21, 2019 somehow, I feel I should weigh in. Jim worked on my LaScalas. Being a novice to this, I am not familiar with what all was done. I have very limited "listenings" to compare them... my R15Ms and [not mine] Forte III... These LaScalas are SWEET! 2 Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted June 21, 2019 Share Posted June 21, 2019 7 minutes ago, WillyBob said: somehow, I feel I should weigh in. Jim worked on my LaScalas. Being a novice to this, I am not familiar with what all was done. I have very limited "listenings" to compare them... my R15Ms and [not mine] Forte III... These LaScalas are SWEET! Your La Scalas got the full treatment with the components that were available at that time, which were the CT125, K55M, and Eminence Kappa 15C woofer, as well as the A/4500 network. The cabinets were fully reinforced at all joints. Don't remember if I did the Dynamat on the mid horn or not....Oh, and the fantastic sounding laser badges! 1 1 Quote Link to comment Share on other sites More sharing options...
Jvitti1970 Posted June 21, 2019 Author Share Posted June 21, 2019 @jimjimbo which caps did you use? Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted June 21, 2019 Share Posted June 21, 2019 5 minutes ago, Jvitti1970 said: @jimjimbo which caps did you use? I have used everything from Dayton caps to Sonicaps to Audiocap Theta to Jantzen to Jupiter VT, and I'm probably forgetting some.....I don't want to say that it's all dependent on your budget, but that is a big piece of the equation because you can spend a whole bunch rebuilding one pair of networks. And, what sounds good to one person may not to another. Some people like Sonicaps, some do not. Some folks like the Daytons because they do a decent job at a very low price point. But then some scoff at them.....Right now I have Jupiter VT and Audiocap Theta in my Khorns, and higher end Jantzen in my LSI splits. Both are AA. 1 Quote Link to comment Share on other sites More sharing options...
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