Cohoangler Posted October 31, 2016 Share Posted October 31, 2016 I need some help rebuilding the crossovers for my Heresy II’s. I bought the speakers in the late 1980’s, so they’re 25+ years old. Everything I’ve read indicates the capacitors are at the end of their useful life, even though I cannot detect a loss of speaker performance. But I’m 25+ years older too, so my hearing probably isn’t what it once was. Nevertheless, after reading a lot of information on this BB, and looking at videos on YouTube, I decided to place an order to Bob Crites for a DIY crossover rebuild kit. Everything I’ve seen suggests the following steps for a crossover rebuild: 1) Remove the crossover from the speaker, 2) identify the capacitors, 3) clip the wires to the caps, 4) unscrew and remove the old caps, 5) attach the mounting tabs, 6) zip tie the new caps to the mounting tabs, and finally 7) solder the wires to the new caps. Seems simple enough. When my order arrived from Bob, I pulled one of the Heresy II crossovers, and I got a surprise. They did not resemble the “tired, old crossovers” on Bob’s website or in any of the videos I’ve seen. In fact, the crossover looked almost brand new. Fresh as a daisy. Plus, I could not positively identify the capacitors, there are no wires in which to clip, and no place to re-solder anything. The caps appear to be attached directly to a circuit board. See the pics. Also, if you look closely you’ll see a date stamp on the circuit board (Apr 04 1988). I believe the caps are the four blue things. If not, where are they? Notice there are no wires going into or out of the caps. The large cap in the lower right corner does have two bare wires that could be clipped and re-soldered, but the new sonic caps won’t fit there. The sonic caps have one wire at each end. But I need a cap with two wires at one end. If I solder in one of the sonic caps, the wire on the far side won’t reach. And I have no idea how to replace the three other caps, given that there are no wires to clip and re-solder. Plus, I’m not convinced the new caps will fit into the same space. The sonic caps are only slightly smaller than the large capacitor in the lower right corner of the crossover. Not sure how I can fit three in the same space. also, when my order arrived, the only thing I got was eight caps (four for each speaker). No zip ties and no mounting tabs. I was under the impression the DIY kits came with those items. Mine did not. I can probably find zip ties in my garage. But I don’t know where to get those mounting tabs. It seems like for a few more nickels, Bob could have included them in the order. Or at least tell me they were optional. I would gladly paid extra for them. At this point, I may just return the kit to Bob. Although the capacitors probably need to be replaced, I’m not sure the risk of destroying the entire crossover is worth the potential performance improvements this rebuild is supposed to provide. Although I haven’t reached that point yet, I am at a standstill. Any ideas or advice would be great. Thanks. Quote Link to comment Share on other sites More sharing options...
babadono Posted October 31, 2016 Share Posted October 31, 2016 Ok. Have you re contacted Bob? The re build kit I purchased from him for my La Scala type AA networks included everything that was needed. Perhaps it is just an oversight on his part? Might he have thought you were talking about Heresy I not II? Can the capacitor leads absolutely not be bent to make work? Quote Link to comment Share on other sites More sharing options...
tigerwoodKhorns Posted November 1, 2016 Share Posted November 1, 2016 Easy stuff. Here is the schematic: Replacing the caps is easy, you just need a tool called a "solder sucker" to remove the old caps from a circuit board. Use a very thin gage flux core solder to attach the new caps and you can easily put just the right amount on (I was doing this yesterday for an LED lighting project). The 4 blue things are the caps. Look at the other side of the board and you will see where the leads go through. Just heat em up and suck the solder off the board. Then pop out the old and put new one in a solder it up. Then clip the excess wire from the leads. Use thin wire flux and you can easily put just the right amount of solder on. I like to heat a little then hit the iron with the solder and let it flow to the board. You should have a little round volcano looking drop of solder on the board with the wire in the center. If you wait for the board to heat up you might heat it too much. Now whether the caps need to be replaced is another story. Quote Link to comment Share on other sites More sharing options...
BEC Posted November 1, 2016 Share Posted November 1, 2016 Here is a picture of a before and after rebuild on that type of Heresy II crossover. Hardest part on this version is getting the wires unsoldered and unwrapped from the input terminal posts. On this one they chose to have the input terminals actually penetrate through the circuit board and connect on top with two stiff wires. Sort of a pain to get those loose so you can get the board off to get to the back side of it. Bob Crites Quote Link to comment Share on other sites More sharing options...
Schu Posted November 1, 2016 Share Posted November 1, 2016 what values are needed Bob? Quote Link to comment Share on other sites More sharing options...
BEC Posted November 1, 2016 Share Posted November 1, 2016 10 hours ago, Schu said: what values are needed Bob? Those values are in the schematic posted earlier. Bob Crites Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 1, 2016 Share Posted November 1, 2016 12 hours ago, BEC said: Sort of a pain to get those loose so you can get the board off to get to the back side of it. What's wrong with clipping the wires right at the old caps and tying on to them there? Quote Link to comment Share on other sites More sharing options...
BEC Posted November 1, 2016 Share Posted November 1, 2016 6 minutes ago, CECAA850 said: What's wrong with clipping the wires right at the old caps and tying on to them there? That would work if any of the crossover wires were left above the board. On all but one of the caps, you cannot even see the wires. The wires have been pulled all the way through with nothing left of the wire visible on top of the board. Bob Crites Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 1, 2016 Share Posted November 1, 2016 Just now, BEC said: That would work if any of the crossover wires were left above the board. On all but one of the caps, you cannot even see the wires. The wires have been pulled all the way through with nothing left of the wire visible on top of the board. Bob Crites I see that now, thanks Bob. I thought they were all built like the bigger one and the Sonicaps where the wire came out the center of the end. Quote Link to comment Share on other sites More sharing options...
Cohoangler Posted November 2, 2016 Author Share Posted November 2, 2016 Thanks everyone for the great responses, including the guest appearance from Bob! This answers my questions. It appears I need to unscrew the circuit board from the input plate, flip it over, un-solder the old caps by melting and removing the old solder, and then pulling the old caps up and out. The wires for the new caps are inserted into the holes from the old caps. The new caps are then soldered directly onto the circuit board. Just clip the excess wire and it's good to go! This also clears up why the rebuild kit did not include zip ties and mounting tabs. I won’t need them since the new caps are soldered directly onto the circuit board. Thanks again. Quote Link to comment Share on other sites More sharing options...
BEC Posted November 2, 2016 Share Posted November 2, 2016 1 hour ago, Cohoangler said: It appears I need to unscrew the circuit board from the input plate, flip it over, Yes, but first you have to unsolder the two wires that attach to the input terminals where they come up through the circuit board. Bob Crites Quote Link to comment Share on other sites More sharing options...
Deang Posted November 2, 2016 Share Posted November 2, 2016 Stupid design. Quote Link to comment Share on other sites More sharing options...
Cohoangler Posted November 2, 2016 Author Share Posted November 2, 2016 Thanks again Bob. I presume you mean those two wires that are soldered to the board, and are directly below the red/orange capacitor in your pic (crossover on the left). Quote Link to comment Share on other sites More sharing options...
BEC Posted November 3, 2016 Share Posted November 3, 2016 2 hours ago, Cohoangler said: Thanks again Bob. I presume you mean those two wires that are soldered to the board, and are directly below the red/orange capacitor in your pic (crossover on the left). Yes, that is it. Bob Crites Quote Link to comment Share on other sites More sharing options...
BEC Posted November 3, 2016 Share Posted November 3, 2016 3 hours ago, Deang said: Stupid design. Or big improvement if you compare to how the Heresy II crossover was done before the circuit board. The one we affectionately call the "Pile of Parts" crossover. Bob Crites Quote Link to comment Share on other sites More sharing options...
Schu Posted November 3, 2016 Share Posted November 3, 2016 ^yikes! Quote Link to comment Share on other sites More sharing options...
Deang Posted November 3, 2016 Share Posted November 3, 2016 A work of art. Bob, I'm fine with the circuit board - I was referring to the rear of the binding posts protruding up through the board with the wires wrapped around them. Quote Link to comment Share on other sites More sharing options...
BEC Posted November 3, 2016 Share Posted November 3, 2016 I agree, better with the circuit board but poorly implemented when it comes time to rebuild. We could also say that about the Quartet network. Looking at the picture I have attached, you can sort of tell there is a screw under the steel core inductor that has to be removed to get the circuit board off. It has to be removed using a pair of long nose pliers to get the circuit board off. Later has to be reinstalled using those long nose pliers. I think that method had to be used at the factory to get that screw installed initially. Bob Crites Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted November 3, 2016 Share Posted November 3, 2016 17 hours ago, BEC said: Yes, but first you have to unsolder the two wires that attach to the input terminals where they come up through the circuit board. Bob Crites I'm always looking for shortcuts, lol. Couldn't you unscrew the transformer and flip the whole thing over? Quote Link to comment Share on other sites More sharing options...
BEC Posted November 3, 2016 Share Posted November 3, 2016 No, you have to separate the circuit board from the plastic input terminal cup. The autotransformer can stay where it is. Bob Crites Quote Link to comment Share on other sites More sharing options...
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