mopardave Posted October 25, 2020 Share Posted October 25, 2020 Since building my Cornscala's which were a Cornwall conversion I'm not liking them much. They sound way laid back compared to the 600 in your face mid horn. Have any of you using the large mid horns noticed this with the Cornscala? Using the zxpc horn with a B&C85. Seems like i have to turn the volume up much further than my Cornwalls or Super Heresy require. Not near as efficient as a typical Klipsch Heritage. Not sure if this is typical of the large mid horn or not. Other thing is using a ALK CSW cross over adjusted to my liking, but still laid back. Maybe the cross over is the culprit or the DE85? Quote Link to comment Share on other sites More sharing options...
Honeybadger Posted October 26, 2020 Share Posted October 26, 2020 What is a zxpc horn? Don't think its the crossover, used it many times, always liked it. HB Quote Link to comment Share on other sites More sharing options...
mopardave Posted October 26, 2020 Author Share Posted October 26, 2020 7 hours ago, Honeybadger said: What is a zxpc horn? Don't think its the crossover, used it many times, always liked it. HB The zxpc horn is a 11x7 open horn. I don't know, but maybe the drivers are just not as efficient as what's used in the Heritage line. A 1/4 turn on the volume knob was all it took to hit 100db levels with the Cornwalls. The Cornscala's at 1/4 turn are at 75db output. Quote Link to comment Share on other sites More sharing options...
Honeybadger Posted October 27, 2020 Share Posted October 27, 2020 Very confusing, I thought the DE-85 was a good bit hotter than the K-55. Since you modified a Cornwall for this project, did you change to woofer or tweeter? HB Quote Link to comment Share on other sites More sharing options...
Honeybadger Posted October 27, 2020 Share Posted October 27, 2020 Do you have the original crossovers? If so, may want to reinstall them as a test. The woofer typically dictates the speakers efficiency. If the oem woofers have been re-used, it is unlikely the efficiency has changed. The issue may be a mis-built crossover, though I have never had one from ALK. HB Quote Link to comment Share on other sites More sharing options...
mopardave Posted October 28, 2020 Author Share Posted October 28, 2020 18 hours ago, Honeybadger said: Do you have the original crossovers? If so, may want to reinstall them as a test. The woofer typically dictates the speakers efficiency. If the oem woofers have been re-used, it is unlikely the efficiency has changed. The issue may be a mis-built crossover, though I have never had one from ALK. HB I do not have the original xover as they were used in my super heresy. I have suspected the woofers as well, but they do test 4ohm. I got a good deal on these 3015lf woofers thru avatar speaker, but they arrived with no decal labels identifying them at all. I am suspicious of this. May have to buy another set of woofers. The tweet is a B&C DE120. Thanks Quote Link to comment Share on other sites More sharing options...
henry4841 Posted October 28, 2020 Share Posted October 28, 2020 The driver has a 107db sensitivity so it is not the problem. It is possible that it is not a good match with that horn. A possibility but I doubt that is the problem. I would look at the crossover as the problem. Without attenuation on the horn driver combination it should hurt your ears with just a touch of the volume control. Way louder than the bass speaker. Very few bass speakers reach 100db sensitivity. Most far less. Attenuation is the problem. If you cannot design a crossover yourself give Bob Crites a call. I bet he can solve your problem. I am not familiar with the crossover you have but if the attenuation is adjustable you do not have it set correctly for your setup. Quote Link to comment Share on other sites More sharing options...
Honeybadger Posted October 28, 2020 Share Posted October 28, 2020 3015 LF is an 8 ohm driver, DCR is 5.5 ohms. A quick look at the specs shows, the 3015 is not a good match for your Cornwall cabs. With no labeling, I am suspect also. The Eminence 15c is very close to the original K-33 and is a suitable replacement. I would consider replacing the woofer with an Eminence 15c or one from Bob Crites. Again I doubt the crossover is the issue, the circuit is fairly simple. If you can post a pic of the crossover, might be able to spot a flaw. HB Quote Link to comment Share on other sites More sharing options...
jwgorman Posted October 28, 2020 Share Posted October 28, 2020 I’m using the 3015lf_4 crossed at 500, and the zxpc 18x10 horn with a Faital ProHF146 with -12db attenuation courtesy of a 3636 autoformer with 1.2uf In front of the AF and 3.0mh in parallel with the driver. I get all the in-your-face mid presentation of my CWIIs only much more refined. I believe the speaks that avatar was selling were 4 ohms, going from memory. I’ve not used that compression driver before but you could experiment with an lpad and see if it’s a level thing. Quote Link to comment Share on other sites More sharing options...
Blvdre Posted October 28, 2020 Share Posted October 28, 2020 What type of horn is the ZXPC? If it's a constant-directivity type, you'll need compensation in the crossover to flatten the falling response. Quote Link to comment Share on other sites More sharing options...
jwgorman Posted October 28, 2020 Share Posted October 28, 2020 The 18x10 and 11x17 are not CD 1 Quote Link to comment Share on other sites More sharing options...
mopardave Posted October 29, 2020 Author Share Posted October 29, 2020 4 hours ago, jwgorman said: The 18x10 and 11x17 are not CD I had the horn size wrong, think it is the 11x17. I don’t have them here. Only 2 pics I have and not very good. Quote Link to comment Share on other sites More sharing options...
jwgorman Posted October 29, 2020 Share Posted October 29, 2020 Can you tell how much attenuation is on the B&C with your crossover? And what is the value of the cap on the mid circuit? I’m not familiar with that crossover. Quote Link to comment Share on other sites More sharing options...
OO1 Posted October 29, 2020 Share Posted October 29, 2020 13 hours ago, mopardave said: I do not have the original xover as they were used in my super heresy. I have suspected the woofers as well, but they do test 4ohm. I got a good deal on these 3015lf woofers thru avatar speaker, but they arrived with no decal labels identifying them at all. I am suspicious of this. May have to buy another set of woofers. The tweet is a B&C DE120. Thanks do you still have the older woofers --- Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted October 29, 2020 Share Posted October 29, 2020 Sounds like the polarity is crossed on a driver. Quote Link to comment Share on other sites More sharing options...
mopardave Posted October 29, 2020 Author Share Posted October 29, 2020 2 hours ago, jwgorman said: Can you tell how much attenuation is on the B&C with your crossover? And what is the value of the cap on the mid circuit? I’m not familiar with that crossover. I have the mid attenuated at 11 and the 120 at 6. I believe the cap is 33 400v. according to B&C web site the DE85 is 108db and 8ohm. Quote Link to comment Share on other sites More sharing options...
mopardave Posted October 29, 2020 Author Share Posted October 29, 2020 1 hour ago, CECAA850 said: Sounds like the polarity is crossed on a driver. I no longer have the K33e's and yes is does sound like the polarity is reversed. I did check the polarity on everything and it checks ok. I did not try switching polarity. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted October 29, 2020 Share Posted October 29, 2020 8 hours ago, mopardave said: I no longer have the K33e's and yes is does sound like the polarity is reversed. I did check the polarity on everything and it checks ok. I did not try switching polarity. Have you made sure that the ohm rating on the new drivers is the same as the stock drivers? 1 Quote Link to comment Share on other sites More sharing options...
Pete H Posted October 29, 2020 Share Posted October 29, 2020 Something is wrong for certain. I used 3 different horns and drivers with Cornscalas, fastracs, ZPX and Goldwood 450's and they all smoked the stock midhorns. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted October 29, 2020 Share Posted October 29, 2020 Have you played one speaker at a time to absolutely rule out a phase issue between the 2 speakers? Quote Link to comment Share on other sites More sharing options...
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