TommyC Posted July 16, 2005 Share Posted July 16, 2005 Hi all. I have been on a small buying binge recently and picked up a fair set of '78 vintage Heresys. One of the tweeters does not work. Is there a way to tell if it is the tweeter itself or wiring/crossover related without doing the replace parts till it starts working method I usually employ? Thanks! Quote Link to comment Share on other sites More sharing options...
BEC Posted July 16, 2005 Share Posted July 16, 2005 You probably need a new tweeter diaphragm. If you have a meter you can measure on the tweeter terminals. A good one should read around 6 ohms. A bad one will read open. If you don't have a meter, you can swap the two tweeters to see if the problem goes with the tweeter or the cabinet Bob Crites Quote Link to comment Share on other sites More sharing options...
TommyC Posted July 16, 2005 Author Share Posted July 16, 2005 ---------------- On 7/16/2005 3:16:48 PM BEC wrote: If you don't have a meter, you can swap the two tweeters to see if the problem goes with the tweeter or the cabinet Bob Crites ---------------- Now why didn't I think of that? Thanks Bob! Quote Link to comment Share on other sites More sharing options...
colterphoto1 Posted July 16, 2005 Share Posted July 16, 2005 ---------------- On 7/16/2005 3:20:46 PM TommyC wrote: ---------------- On 7/16/2005 3:16:48 PM BEC wrote: If you don't have a meter, you can swap the two tweeters to see if the problem goes with the tweeter or the cabinet Bob Crites ---------------- Because Bob is the MASTER! Michael Now why didn't I think of that? Thanks Bob! ---------------- Quote Link to comment Share on other sites More sharing options...
TommyC Posted July 16, 2005 Author Share Posted July 16, 2005 OK. Both tweeters work in one and neither works in the other! I have a feeling this may get over my head pretty quickly now! I checked as closely as I could and found no Obvious wiring issues, but my knowledge becomes limited pretty quickly when you get beyond part swapping! Quote Link to comment Share on other sites More sharing options...
BEC Posted July 16, 2005 Share Posted July 16, 2005 OK, take a good look at the wires on the two crossovers. You may need to remove them to see them well enough. Both should be the same and you would be looking for a bad looking connection on the bad one or a broken wire. Another possibility is that the tweeter capacitor could be bad enough that you get no sound through it. That is rare, but I have seen that before. I assume that you have the K-77s with round magnets and that the wires from the crossover to the tweeter were changed in the test which would have eliminated that wiring as being a problem. Bob Quote Link to comment Share on other sites More sharing options...
TommyC Posted July 16, 2005 Author Share Posted July 16, 2005 Thanks Bob. Once I pulled the Crossover out the bad wire was obvious. It was broke right where it attached to the terminal strip! Life is good again! ---------------- On 7/16/2005 3:41:31 PM BEC wrote: OK, take a good look at the wires on the two crossovers. You may need to remove them to see them well enough. Both should be the same and you would be looking for a bad looking connection on the bad one or a broken wire. Another possibility is that the tweeter capacitor could be bad enough that you get no sound through it. That is rare, but I have seen that before. I assume that you have the K-77s with round magnets and that the wires from the crossover to the tweeter were changed in the test which would have eliminated that wiring as being a problem. Bob ---------------- Quote Link to comment Share on other sites More sharing options...
BEC Posted July 16, 2005 Share Posted July 16, 2005 Good. Now fire those puppies up and give them a good workout. Let us know how they sound. Bob Quote Link to comment Share on other sites More sharing options...
TommyC Posted July 17, 2005 Author Share Posted July 17, 2005 Well, after several hours of listening and side by side comparison with my '85 vintage Heresys, these '78 vintage ones sound better. My wife nailed it when she said they have a "slightly richer" sound. Is this normal or do I need to be looking into my '85s a bit closer? The '85s look a LOT better as they are very well cared for oiled walnut while the older ones are birch that were not so well cared for. Also... Why, now that I have two pairs of Heresys, do I feel this Need to start modding the heck out of one set? Quote Link to comment Share on other sites More sharing options...
BEC Posted July 17, 2005 Share Posted July 17, 2005 Doing a rebuild on the crossovers would be a good place to start. At least on the 1978s I think the original caps are somewhat out of spec by now and you have already found that one had a wiring problem. Bob Quote Link to comment Share on other sites More sharing options...
TommyC Posted July 17, 2005 Author Share Posted July 17, 2005 ---------------- On 7/17/2005 8:56:35 AM BEC wrote: Doing a rebuild on the crossovers would be a good place to start. At least on the 1978s I think the original caps are somewhat out of spec by now and you have already found that one had a wiring problem. Bob ---------------- Do you (or anyone else you know of) do that as a service for people like me who can't even read an electronics diagram? It is something I have been thinking about for my '85s for a while, but I wouldn't even knwo where to start. Quote Link to comment Share on other sites More sharing options...
BEC Posted July 17, 2005 Share Posted July 17, 2005 Yes, Contact me by email or PM for all the information. Bob Crites bobcrites@centurytel.net Quote Link to comment Share on other sites More sharing options...
djk Posted July 17, 2005 Share Posted July 17, 2005 The woofer to midrange crossover is messed up on the Heresy II, they sound funny in that region. The Forte and Cornwall II use basically the same MF and HF parts and sound fine, so it's not the MF (a lot of people think it is the K55V, but this disproves that idea). Consider having Bob or Dean hop up your early Heresy networks. Quote Link to comment Share on other sites More sharing options...
DrWho Posted July 17, 2005 Share Posted July 17, 2005 It's always the cable isn't it? One of these days somebody better invent a wire that is cheap and doesn't fall apart. Practially 99% of the problems with audio are with the bloody cables. Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 17, 2005 Share Posted July 17, 2005 ---------------- On 7/17/2005 2:50:13 PM DrWho wrote: It's always the cable isn't it? One of these days somebody better invent a wire that is cheap and doesn't fall apart. Practially 99% of the problems with audio are with the bloody cables. ---------------- Dennis, What are you saying about the HII? Do you mean all of them? We have a pair of each in the house -- originals and HII. The HII sound a bit smoother to us, but not necessarily lacking. Bruce Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.