mcp Posted May 13, 2010 Share Posted May 13, 2010 I bought a pair of Cornwall IIs locally a couple of months ago and have noticed that the bass is weak. When I recently replaced the crossovers with Crites crossovers, I noticed that one woofer was a K-33 and one was a K-34-E, so I'm guessing abuse occurred at some point. The speakers are in the corners of a small room (11 X 13) and the bass seems weak compared to other smaller speakers I've used in this room (Avid 103's, Paradigm Studio 20's). I'm using a Harman Kardon 430 right now while Craig restores my Scott 222C; but I have to admit I'm a little bummed by the results so far. My memory of hearing the Cornwalls at different times over the years was that of a very solid bottom end - even a little thick at times - which appeals to me. Not sure what to do ... Quote Link to comment Share on other sites More sharing options...
4tay Posted May 13, 2010 Share Posted May 13, 2010 Two courses of action: 1) Are the woofers being driven in phase? Do you have one of the leads from the crossover or on the driver reversed by accident---or the previous owner? 2) Have you ohmed the woofers? I am wondering if they are meeting spec (both the same value like 8 ohms) Quote Link to comment Share on other sites More sharing options...
mcp Posted May 13, 2010 Author Share Posted May 13, 2010 It's funny you mention that because when I first heard them at the seller's house, I knew the woofers were out of phase. Whoever put the K-33 woofer in had it wired out of phase. But they are in phase now. I did not put a meter on them...probably should have when I had them out while I was replacing the crossovers. I'm also wondering if this is just some unfortunate room interaction with the room and the 15" woofers...although the bass was weak in my 13X 17 living room, too. Quote Link to comment Share on other sites More sharing options...
4tay Posted May 13, 2010 Share Posted May 13, 2010 It's funny you mention that because when I first heard them at the seller's house, I knew the woofers were out of phase. Whoever put the K-33 woofer in had it wired out of phase. But they are in phase now. I did not put a meter on them...probably should have when I had them out while I was replacing the crossovers. I'm also wondering if this is just some unfortunate room interaction with the room and the 15" woofers...although the bass was weak in my 13X 17 living room, too. If the drivers seem ok, then the other thing I can think of would be if one or both inductors are bad on the crossover. Quote Link to comment Share on other sites More sharing options...
mcp Posted May 13, 2010 Author Share Posted May 13, 2010 The crossovers are brand new from Crites... Quote Link to comment Share on other sites More sharing options...
Frzninvt Posted May 14, 2010 Share Posted May 14, 2010 The 1986 on Cornwall II cabinet has no internal damping material. If you rap your knuckles on the side the cabinet will resonate. I would add some acoustic foam with spray glue on the three non-opposing sides to improve the bass response. The acoustic foam can be purchased from Parts Express. There is no difference from a specification standpoint on the K-33 and K-34, the K-34 just has a smaller decorator paper lip so that it sits flush with the cabinet motorboard. The K-33 would protrude slightly, they should perform identically. Good job on the replacing the networks the original ones look like they were built by playschool - very cheap. Quote Link to comment Share on other sites More sharing options...
mcp Posted May 15, 2010 Author Share Posted May 15, 2010 Is this something you've tried? I'm always hesitant to mess with a design that's been so successful for so long... The 1986 on Cornwall II cabinet has no internal damping material. If you rap your knuckles on the side the cabinet will resonate. I would add some acoustic foam with spray glue on the three non-opposing sides to improve the bass response. The acoustic foam can be purchased from Parts Express. There is no difference from a specification standpoint on the K-33 and K-34, the K-34 just has a smaller decorator paper lip so that it sits flush with the cabinet motorboard. The K-33 would protrude slightly, they should perform identically. Good job on the replacing the networks the original ones look like they were built by playschool - very cheap. Quote Link to comment Share on other sites More sharing options...
Pete H Posted May 15, 2010 Share Posted May 15, 2010 Is this something you've tried? I'm always hesitant to mess with a design that's been so successful for so long... The 1986 on Cornwall II cabinet has no internal damping material. If you rap your knuckles on the side the cabinet will resonate. I would add some acoustic foam with spray glue on the three non-opposing sides to improve the bass response. The acoustic foam can be purchased from Parts Express. There is no difference from a specification standpoint on the K-33 and K-34, the K-34 just has a smaller decorator paper lip so that it sits flush with the cabinet motorboard. The K-33 would protrude slightly, they should perform identically. Good job on the replacing the networks the original ones look like they were built by playschool - very cheap. I have done this on my C2's and there was an improvement after the material was added. I don't know why there were variations in the use of damping material in some boxes and none in others as it is my understanding that all the original Cornwalls had it and that some of the C2's had it and the C3's have it.????? Wish someone from Klipsch would chime in and explain that one. Quote Link to comment Share on other sites More sharing options...
wantabeach Posted July 15, 2014 Share Posted July 15, 2014 Crites uses polypropylene capacitors which I understand can sound thin compared to the paper-in-oil film caps in my Cornwall I's. Not sure what kind of caps the Corn II's came with. Quote Link to comment Share on other sites More sharing options...
djk Posted July 15, 2014 Share Posted July 15, 2014 "Not sure what kind of caps the Corn II's came with. " Mylar. Quote Link to comment Share on other sites More sharing options...
Schu Posted July 15, 2014 Share Posted July 15, 2014 Weak bass on a cornwall... something MUST BE wrong. I second the phase idea because weak bass and cornwall should NOT be used in the same sentence. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted July 15, 2014 Share Posted July 15, 2014 Maybe he figured it out sometime in the last 4 years. 2 Quote Link to comment Share on other sites More sharing options...
Schu Posted July 15, 2014 Share Posted July 15, 2014 Hahaha... didn't see that. Who's the bumpasaurous? 1 Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted July 15, 2014 Share Posted July 15, 2014 Hahaha... didn't see that. Who's the bumpasaurous? Wantabeach???? Quote Link to comment Share on other sites More sharing options...
peshewah Posted July 15, 2014 Share Posted July 15, 2014 Thats funny Quote Link to comment Share on other sites More sharing options...
Dr Morbius Posted July 16, 2014 Share Posted July 16, 2014 4 years? Good Lord, I hope he has found the problem by now. Quote Link to comment Share on other sites More sharing options...
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