jackthedog Posted September 8, 2017 Report Share Posted September 8, 2017 I read most of the KLH rebuild threads but there was no mention of how to remove the aluminum base plate from the cabinet. After removing the 4 screws, it seems to be somehow attached to the face plate unless I am missing another fastener? Thanks in advance. Dog Link to comment Share on other sites More sharing options...
JKent Posted September 8, 2017 Report Share Posted September 8, 2017 Hey Dog. Welcome! It's been a while since I worked on these and I no longer have the speakers but IIRC you need to go to the back and remove the speaker terminal nuts, the level knobs and the nuts that hold the level control pots in place. Then the whole thing should pull through from the inside. Be careful not to lose the insulating washers or grommets. You don't want the speaker terminals or anything else shorted against the aluminum plate. Kent Link to comment Share on other sites More sharing options...
jackthedog Posted September 8, 2017 Author Report Share Posted September 8, 2017 That would be way too easy. I saw some photos where the complete face plate came out with particle board still attached. Thanks, will give it a shot. Dog Edit: Came right out. Face plate remains. Link to comment Share on other sites More sharing options...
JKent Posted September 8, 2017 Report Share Posted September 8, 2017 3 hours ago, jackthedog said: Came right out. Face plate remains. Great! Ask any questions. I've rebuilt 5 or 6 pair of these with everything from budget to big expensive caps (I prefer budget). If you read my previous posts you'll see I recommend replacing the 5w resistors with 10w. You don't need anything fancy--plain ol' wirewound resistors work fine. I've seen burned 5w resistors in a KLH Five and a KLH Twelve and figure new resistors are cheap insurance. Don't be confused by the odd original caps. Many of them are double caps in one case with some being wired as 2 separate caps and some wired up in parallel to make a single cap of double the value. It can be confusing. This thread may be helpful, and it has links to other threads: And this thread started by Geoff ("stupidhead") has some useful info and pics. It also underscores how confusing those damn double caps can be, even for an experienced restorer: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/8579-1967-klh-model-5-refurbish-1967/#comment-105677 Finally, I found that the Fives benefitted from Roy's woofer goo. It's the same as the butyl sealant used originally and you'll see the service bulletin in the Library where KLH recommends re-doping all woofers. But DO NOT use anything other than Roy's goo (also sold by Vintage AR on ebay). Other formulas will ruin the speakers. Kent Link to comment Share on other sites More sharing options...
jackthedog Posted September 8, 2017 Author Report Share Posted September 8, 2017 Thx. Mine only has one double cap and they are not in parallel. Resistors havent drifted much but might as well replace. Already have the goo order in. jack Link to comment Share on other sites More sharing options...
couldbfishin Posted September 14, 2017 Report Share Posted September 14, 2017 I am in the process of restoring a pair of Model 5's right now. I removed the four screws from inside the cabinet, and the faceplate simply peeled off the inside wall of the cut out as I removed the crossover. I didn't remove the knobs or speaker terminals. The faceplate remained attached to the crossover and I removed the entire assembly in one piece. As you can tell from the photo, there was some type of sealant or adhesive on the edges or the cut out, and some of the wood came off. I will sand the rough surface before reinstalling the faceplate and crossover. I also intend to reapply sealant around the edge of the cutout where the faceplate will seat. Model 5's were sold from 1968 till 1972 from what I have read. So this crossover, dated Jan 25, 1968, with a serial number 7,756 is an early model. The woofer has a round magnet, the sealant used was dough like, and the bundled caps were a 2 uF and a 3 uF, instead of a 3uF and 4uF as the schematic I have shows. I intend to replace them with a 3uF and a 4uF, as used in the other crossover I have. The second speaker in this pair has a serial number in the 34,000's. The faceplate is plastic, and the circuit board is phenolic. There are no bundled caps on this crossover. I have not been able to upload photos of it for some reason, but if you are interested, let me know by PM and I will try again. My next project will be to restore a pair of model 6's. I have not been able to locate a schematic drawing. If anyone reading this has one, or knows where I could get one, please let me know. Thanks and I hope this helps someone. Link to comment Share on other sites More sharing options...
JKent Posted September 14, 2017 Report Share Posted September 14, 2017 10 minutes ago, couldbfishin said: the bundled caps were a 2 uF and a 3 uF, instead of a 3uF and 4uF as the schematic I have shows. I intend to replace them with a 3uF and a 4uF, as used in the other crossover I have. Welcome fish I think you're making the same mistake others have made. The "2uF" cap actually has 3 leads--one common (black) and two red. Each red is 2uF. 10 minutes ago, couldbfishin said: The faceplate is plastic, and the circuit board is phenolic. There are no bundled caps on this crossover. I have not been able to upload photos of it for some reason The other speaker is a later version. Attached are before & after PCBs from that version. I used Carli caps and 10w resistors. -Kent Link to comment Share on other sites More sharing options...
couldbfishin Posted September 14, 2017 Report Share Posted September 14, 2017 Thanks Kent, you are exactly right. The cap I thought was a 2uF does have two red leads. I had not noticed them. I was not aware a capacitor could be wired this way. This is my first crossover rebuild. The board you show for the later model 5 is beautiful. Nice work. And I had read already that you recommend 10w resistors instead of going back with 5w as they were originally. I planned to do that. Do you by any chance have a schematic for the model 6? Link to comment Share on other sites More sharing options...
jackthedog Posted September 14, 2017 Author Report Share Posted September 14, 2017 I am half way thru recapping. Waiting on the 4uf as they aren't that easy to find in PP. The resistors all test on the money so I am not replacing. They are buried under all the wiring and I dont want to butcher it up as they wrapped the leads pretty well and poured on the solder. But the 6 ohm apparently does not test in circuit (or does it?) as I get a 1 ohm reading. So will have to pull it to check. Its stamped July 31, 1969. Link to comment Share on other sites More sharing options...
JKent Posted September 14, 2017 Report Share Posted September 14, 2017 couldbfishin: Good luck with the Five--it's fairly ambitious for a first crossover rebuild. Some other models have just 1 or 2 caps and none of those confusing 2-part jobs. Just take your time and ask any questions. I've never worked on a Six but found this post with instructions and schematic: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/2426-klh-six-schematic-and-instructions/ Jack: You can use mylar or polyester. 3.9uF is close enough if you can't find 4.0. I think in my photo above I used a 3.9uF Carli + a 0.1 mylar but that's not really necessary. You can also put two 2uF caps in parallel. -Kent Link to comment Share on other sites More sharing options...
jackthedog Posted September 15, 2017 Author Report Share Posted September 15, 2017 I ordered some 4uf polyester Erse though I prefer PP. Cheap and acceptable to me. That spot is pretty tight to start paralleling caps. Link to comment Share on other sites More sharing options...
jackthedog Posted September 20, 2017 Author Report Share Posted September 20, 2017 Is only one coat of butyl on the woofer surround required? Or would two thin coats be better? Or even one coat on each side? I don't think one coat will even make a dent in the bottle. Edit: Disregard. Due to the low viscosity of the sealant, one coat soaks in pretty well. After also coating the surfaces flush with the face (fabric on cone and basket) it took half of the bottle. Which means I should acquire one more pair! Link to comment Share on other sites More sharing options...
JKent Posted September 20, 2017 Report Share Posted September 20, 2017 Don't over-do it. Try one coat, do the 3-finger push test and see how it is. If you need a 2nd, OK. Link to comment Share on other sites More sharing options...
jackthedog Posted September 20, 2017 Author Report Share Posted September 20, 2017 Probably overdid it. It soaked in so much that I added another light coat as all of the fabric threads were still seen individual. Now, only the top thread of the fabric is still protruding from the level of the butyl mixture. Takes some time for the cone to rebound so all is good. Link to comment Share on other sites More sharing options...
JKent Posted September 30, 2017 Report Share Posted September 30, 2017 Also see Service Bulletin #60 in the Library: http://www.classicspeakerpages.net/library/klh/other/klh_schematicsservice/klh_service_bulletin_60.pdf Sorry I didn't say that earlier. It states that ALL KLH speakers brought in for service (regardless of the reason) should have the butyl sealant applied to the woofer "skiver" (surround) and the dust cap. On the Model Five and Twelve the sealant should also be applied to the skiver (only) on the 12.5 midrange driver. Those mids always seem well sealed to me but that's the word from the factory. -Kent Link to comment Share on other sites More sharing options...
jackthedog Posted October 9, 2017 Author Report Share Posted October 9, 2017 One of the 10 ohm restistors floated up to 11.1 ohm and I didnt replace (didnt have any at the time). Since I have already sealed (butyl) the speaker into the cabinet, I really dont want to get into it again. Questions: Does the pot on the lpad have enough adjustment to take care if this? How much is the "sound" affected? I believe it was the one located near the corner of the mount. Link to comment Share on other sites More sharing options...
JKent Posted October 9, 2017 Report Share Posted October 9, 2017 I wouldn't worry about the resistor. 11% off seems OK. But what do you mean you sealed the woofer into the cabinet with butyl? The sealant goes on the cloth surround. Speaker frame should be sealed to the baffle with foam gasket or duct seal. Link to comment Share on other sites More sharing options...
jackthedog Posted October 9, 2017 Author Report Share Posted October 9, 2017 The old foam seal was shot so I put some butyl tape around the baffle. Makes a great seal. http://www.homedepot.com/p/Fabral-1-4-in-x-40-ft-Butyl-Rubber-Sealant-Tape-40BT/207149821?&cm_mmc=Shopping|THD|B|0|B-BASE-D22+Roofing|&mid=7IRJq6AI|dc_mtid_8903vry57826_pcrid_74285768029022_pkw__pmt__ Link to comment Share on other sites More sharing options...
JKent Posted October 9, 2017 Report Share Posted October 9, 2017 Oh. Good to know. Link to comment Share on other sites More sharing options...
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