JKent

Hmmmmm. Roy said the tweeter crosses over at VERY high frequency. Bill said the tweeter output is woefully inadequate. I know my EARS have become woefully inadequate at very high frequencies as I age. Maybe it’s not the tweeter 😉

I had noticed scorched, burned or cracked resistors in Fives and Twelves. Based on that I always replaced all of the 5w resistors with 10 or 12w. RoyC, who knows far more about crossover design than I isolated the culprit as the 5 ohm resistor in the woofer circuit. I’m away from home now so don’t have access to my notes or photos. Maybe Roy will chime in here. He recommended 15 or 20 watts for that 5 ohmer. I no longer advocate replacing all the resistors. They don’t normally go bad unless they are too weak for the job and that would apply to the 5 ohm 5w woofer resistor.

Only the woofer resistor must be replaced and that should be 15 or 20 watts.

http://www.millersound.net call first and ask if Bill can fix it.

Thank you! This is absolutely excellent. It should be pinned to the beginning of the KLH section and/or put in the Library. I'v done a lot of these Model Fives. Wish I'd had this reference before 😀 I'm on the road and may have specific comments later. Roy and I have been going back and forth about the resistors and maybe he'll chime in with his insights. Kent

His in box may be full but he should see this post.

Hi Mark Please send a PM with your email Kent

Cool! Love the old trucks. I'll have to look into JRiver--never heard of it before.

A lot of info in this thread on rebuilding the contour boxes:

Unlike your search for knobs you're in luck here. Those were called the "Twelve point five" drivers and KLH used them in a LOT of applications. They were only used as mids in the Five and Twelve speakers but they were used full-range in the Eight, Thirteen and Twenty-One radios. They were also used full-range in the compact systems such as the Eleven and Eleven-W and in some compact speakers such as the Fourteen A and B, Fifteen, Nineteen and others. Any 4" KLH driver from that era that looks right is probably right. Kent

Good luck with that. They're rare. I thought I found some once but they were same style, just much bigger . I wound up using some stove knobs like these https://www.tubesandmore.com/products/knob-davies-1550-daka-ware-large-skirted-pointer. Just check the size! Kent

Ah. I've done that myself (your suggestion as a sub for Kimpac). Thought maybe Vern's was completely stuffed with poly.

Thanks for the write-up. One question: Is that poly-fil in one pair? Some years back Prof John O'Hanlon wrote a scholarly paper on the microscopic and sonic differences between fiberglass and acousti-fil. He found significant differences as I recall so I wonder whether that would be another variable in your comparison, besides the obvious Hi-Vi vs OEM difference. Kent

Little low end. Any chance they’re out of phase? I’d try reversing the speaker wires on one just to check.

Maybe have it repaired. Bill does great work http://www.millersound.net/index.html

I just heard from a fellow in Canada, Patrick, who bought some of my dynaco speaker badges. He sent me photos of his speakers and the custom stands he had made for them. Here's a picture. He said I could pass along his contact info. I suggested he join CSP but in the meantime you can PM me for his contact. btw, his comment regarding getting the speakers up on stands: "What an incredible difference that made to the sound produced! It's like night and day difference."

oooo I was so focused on the woofers I missed those. rolsonca94530, This could be a big project, and not cheap. But it could also be very rewarding. The 2ax is a really nice speaker. So here's what you'll need: The cabinets need work as you can see but they look basically sound. Do you have the skills to refurbish them? The grilles aren't great and I think I see a hole. The "perfect" fabric is no longer available but you can probably find some suitable linen. Grille badges are missing. There are reproductions but they aren't perfect. The woofers have to go. They need refoaming but they are not original. Ebay often has originals. One mid is good. Let's hope the silent one is too. Could be a crossover or pot issue. The tweeters are wrong. Maybe you could keep them, since there's not that much that you'll hear in the high frequencies. Used originals will have issues. There are other options if you decide to go down that path. Capacitors have to be replaced. No biggie. The pots should probably be replaced. You could try cleaning them but they usually go bad again. You can use inexpensive L-pads or more expensive potentiometers. So. You in for a big project? You'll get plenty of advice here and IMHO the results could be well worth it. Kent

Well don’t keep the OP in the dark. Looks like the woofers were replaced with no-name subs, probably because of foam rot. They should look like this: http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_pictures/ar-2ax_pictures_from_jkent/ar-2ax_pictures_from_jkent_.html

Maybe the new KLH Model Five stands?

Just a thought, and maybe Gene will correct me if I’m mistaken, but I might try Howard Restore-a-Finish, Dark Walnut on the light face frame.

falconacoustics.co.uk works for me. I clicked Jeff’s link above Or try https://www.falconacoustics.co.uk/ls35a-kit-falcon-minimonitor-q7-systems/alcap-claritycap-solen-audio-capacitors.html

Here are 2 pictures of my ar-4x speaker. It's a 2-way like your 2x so essentially the same crossover except for the capacitor value. On the top is the new pot and on the bottom is the original. You can see the layout is the same. So, the Yellow + lead to the Tweeter goes to B. The single Green wire from the external speaker terminal #1 goes to 1. TWO Green wires go to 2: the Tweeter - and one lead from the capacitor. So it would appear the Ohmites are wired the same when viewed from the back: Yellow to the center tab, one Green on the left (1) and 2 greens on the right (2). I hope this is helpful.

Sorry I didn't notice this before. Those pots were replaced once, so you don't have Aetna-Pollack originals. Those are Ohmites. Ohmites are good but as you can see they are open in back and that won't do with the fiberglass stuffing. So there have been several "solutions". Some folks built little boxes. In my case, I used a small plastic project box in my AR-3a's. What a PITA! So I was glad to be able to supply the new, sealed pots to folks like you. I'm afraid I don't recall how the Ohmite tabs correspond to the A-P but I'll try to do a little research.

Ah yes--forgot you're on the other side of the pond. I'm guessing Cornwall 🙂 So Falcon has the 20uF in both NPE (Alcap) and film (Solen). For the 16uF you'll have to use 2 values in parallel (Alcap, 8+8 or 10+6) or just use a 15uF Solen or, if you're really OCD put a 15 and a 1 in parallel. FWIW I don't think I've ever removed the xo board to work on it. They're glued and stapled and prying one out will probably cause it to break. Working through the woofer hole isn't that bad and as Stimpy mentioned you can cut out the old caps leaving the leads (make little fish hook ends to attach the new caps. You still need to solder but this is way easier).