jessiAV

You are right. I was sleepy when I ran these measurements and used a component tester running at 100k, which is the industry standard. Dumb me.. Here are a few tests on the Mundorf E-caps run at 820 hz: 3.9uf indicated: 4.3uf 22uf indicated: 23.5uf 15uf indicated: 16.5uf I also think I see a partial reason the 5 ohm, 5 watt resistor fails. When the original Temple drifts to 40uf, the power running through it substantially increases if I'm not mistaken.

While renewing the caps on one of my KLH Five boards, I thought it might be informative to measure the ESR and capacitance of both the old Temple caps and the new Mundorf E-caps . Here are their results: Temple: 25 uf indicated: now 40.5uf .34 ohms Temple dual cap: 4/4uf indicated: now 6.9 and 7.2uf both 2.1 ohms Temple dual cap: 4/3uf indicated: now 7.5 /8.4uf and 1.9/2.2 ohms respectively Mundorf: 4uf indicated (5% tolerance): Cap #1 measures 4.9uf .33 ohms Cap #2 measures 4.9uf .32 ohms Cap #3 measures 5.0uf .35 ohms Cap #4 measures 5.0uf .31 ohms Mundorf: 15uf indicated (5% tolerance): Cap #1 measures 17.5uf .37 ohms Cap #2 measures 17.5uf .48 ohms Mundorf: 22uf indicated (5% tolerance): Cap #1 measures 25.1uf .3 ohms Cap #2 measures 25uf .32 ohms Mundorf: 2.7uf indicated (5% tolerance): Cap #1 measures 3.4uf .6 ohms Cap #2 measures 3.4uf .61 ohms Okay yes, maybe this is TMI? ::laughing::

Thank you Roy, for the Madisound link. You are so right, Mundorf's upper tier caps are crazy expensive, are they not? Mundorf's E caps (bi-polar electrolytic) sold at the Partsconnexion link that Kent posted above (on march 10) are similarly priced to Madisound's MDl PP and 'lytic caps, and I was planning on fitting those. When I've worked on the crossover's to get the driver levels correct, I will post my impressions of the Fives here. I will say now however, that as your magic sealant dries the bass just gets better and better. Loving it!

No worries Mot. We all here to share what we've learned and to ask questions.

Thanks Kent. Yes, I plan to replace those red electrolytic's with equivalent Mundorf E-caps, other than the tweeter caps which may be noticeably improved by using some special Russian oil caps I've been hording for a special application such as this. And as you may well have guessed, these original caps have drifted up in value, the 4uf's now reading about 6uf, the 16 around 22uf. Of course, that means too much lower frequency energy feeding into the mids and tweeters. That is not good, although it's very typical for un-restored Vintage speakers.. Also, I plan on following your and Roy C's recommendation to replace the 5 ohm woofer resistor with a 10 watt. That should be adequate power handling for my use, and these Fives will be staying with me for a long time. BTW, Mundorf's are offered by both Parts Connexion in Canada and Soniccraft here in the USA. Do you have a opinion as to which source is better?

Additionally, here is an edited photo showing the caps that are directly in the signal path (in series) with their associated drivers when the rear output switches are in their 'normal' positions. Some Five owners may wish to use better quality capacitors in these locations, where they have a greater effect on sound quality? The yellow rectangles show both caps that are in series with the tweeter, and the green rectangle shows the midranges capacitor. The iron core (with the metal strap over coil) inductors are also in the signal path, one to the woofer and one to the midranges.

Kent's diagram regarding the orientation of the 3/4 uf cap is correct. Maybe this picture of the PCB that I scribbled on will show why?

Kent, Okay, today I removed one of my pc boards for oxide removal (xo's are low voltage, high current circuits, so their connections should be kept quite clean), and I see now that they are identical to your #112470. So that indicates that most of the newer Fives' PCB's probably had full soldered traces. One mystery solved, maybe?

Here is a photo of one of my Five's crossover PCB boards -

Kent: Darn, my Fives are temporarily back together, so I cant accurately answer your question yet, but I will look when I apply Roy's seal (within a week or so?). Still, my memory is the color of the board is identical to your 06845 pic, which kinda makes little sense as mine show a higher number than both of your boards (and maybe were made at a later date?). There is no date stamped on the magnet of the one woofer I've removed so far. Brad: Maybe your Fives are typical (?) as my midranges play louder than the tweeters and woofers, this before re-capping of course. Or alternatively, mine currently have an edgy-ness in their upper response that may make them be perceived as louder? Also, one of my speaker's output seems slightly lower than the other, and I suspect this may be due to the original caps failing differently even though all their ESR's read quite good (less than 1/2 ohm) . When the woofers are out again, I will also measure their capacitance (I was in a hurry to reassemble & audition them today, and didn't pause to check). BTW, here is the seller's picture of my speakers:

Wow!! Thank you Kent 😃 those are great pictures and they now reside in my Five's file. Forgot to post my PCB Five's serial numbers for everybody. They are 034947 and 0349xx (label is torn). Maybe that will further help with your thoughts regarding when the PCB was introduced? And I've ordered some of Roy C.'s magic sealant 😀

Thank you Kent and Roy for your insights into the Fives and your recommendations. Very helpful !! Roy, the seal for the wires into the midrange box is a soft caulk and one had pulled away from it's hole, causing a leak. Good call. Something to re-check when it all goes back together. Kent, yes I've read through most of your expert write-ups on the Five's crossover here on CSP. Thanks! After I get everything back to stock and the drivers re-sealed, I will look into upgrading the caps, probably with the Mundorf caps. Ten watt resistors also sounds like a very good idea (the pic of the cracked resistor was very convincing), but I keep my volume levels low so I may not upgrade those unless I sell these (which I doubt I will do). BTW, somewhere here I thought I saw a photo here showing the foil side of the Five's PCB. Does anyone know where it is?

Thank you Kent. My suspicion is that the midrange chamber is open somewhat as pushing on one mid cone does not move it's neighbor. Maybe sealing here is not critical to the overall performance though? The midranges seem to play similarly, but it is difficult to acoustically isolate them by listening while they are in the cabinet of course. I will listen more soon and report back. Also, are the iron core XO coils only used as bypass components, and not in the signal path? And also, what are the best sounding caps you have found for renewing the Fives?

Earlier this week I added a pair of KLH Fives to my collection and I have a few questions for you all, if I may ask? These are the later Fives with the PCB xo board, and with visible wood screws securing the midrange chamber to the front baffle. First, it's clear the fabric surrounds desperately need treating with Roy's/Vintage-AR's sealant. Currently, a search turns up no way to purchase a bottle however. Any suggestions on how to obtain some? Also, I believe the two midranges share a common chamber that should be well sealed from the larger woofer chamber? Is that correct? And finally, there appears to be extra brown sealant between the cone and dust cap on one midrange. It looks much like the factory sealant; could it be original? my sincere thanks

I'm smiling Norman, as I have almost identical equipment in my system rotation. My A10DC sounds exactly as you describe, impressively neutral, although currently I am using a Sansui AU 717 into my OLA's for it's warmth. While I recap, or not, on a case by case basis, two years ago I renewed the old decoupling power supply caps in my Advent 300 and it made a delightful and dramatic improvement.

Just one last mention that these are still available, but I will be listing them on the local markets very soon. Also worth noting, the grills are original and the small scratch is very minor. It would be nice to see these go to someone here and any fair offer should be fine. Plus, the AR 5 crossovers will be free to any CSP member who would pick them up.

In our showroom in the 1980's, Yamaha's CR 420-Cr 620 and Cr 820 (silver faced receivers) matched extremely well with the Boston A 40, 60 and 100's. Probably those and the BA 150's would do equally well with the bigger Yamaha integrated amps but I don't remember those combinations very well. The rear showroom wall was of an older brick construction and seemed to help the Boston's wall-oriented design really sing!

A pair of XO's from poor little AR-5's that were sadly gutted before I got them. One still had a factory tag: K 17106

A pair of the newer style (1970+) AR2ax's. These were in excellent condition condition with minimal use when I got them and have strong output from the tweeters. The woofers were refoamed with the BA filled fillet surrounds and the pots cleaned about 4 years ago, and have performed well since. The grills and cabinet wood look almost new but one side wood panel has a single scratch about 1/2 inch long. These are on Interstate near the California Oregon boarder and I prefer pick up to keep them as nice as they are.

Were I in your situation, I would use original Advent woofers, either the Masonite ring or the steel frame version. This is because the Advent woofer cone/voice coil assembly's were made by Advent in-house and is one reason why OLA's sounded like they did. We are fortunate that these woofers are still available on the used market and are typically quite durable unless abused. However, please note that while I am familiar with the sound of both Masonite (I currently own two pairs of OLA's) and metal woofer Advents, I have never auditioned the Simply Speakers version. Just my opinion, of course..

Fortunately, your problem is a disconnected, and not shorted, wire. Chances are highest that the wire is broken where it enters the molded plug. If so, you could try opening the wire's insulated covering there and look for a break. It may also be necessary to cut part of the molded plug as well, for better access. The lesser possibility is that the wire has broken at the tip of the metal pin, especially if it is soldered. Heating and re-flowing the solder ~may~ reconnect things then. To maximize the possibility of success, my suggestion is, that unless you are very skilled at soldering, to take your cable to a electronic repair facility and get their thoughts on fixing it. Be prepared for the likelihood that they will have to do the above work and alter the appearance of the plug.

In these older cables, due to a absence of serviceable replacements I have typically been moved to repair the existing items. Can your plug covers be successfully opened to allow repair? There does not appear to be any seams in this picture but it would be odd that a fully molded plug would short internally..

If this would be of interest(?); original untouched KLH Six epoxy woofer with textured cone, serial number 068038