21 replies to this topic

[Marigold]

My first restoration project, KLH Model 17. I just opened them up and found the crossovers/capacitors looking different than every picture I've seen on the net.
Have these speakers already been recapped?








This is what I was expecting to find, this pic from a post documenting a restoration of Model 17's.

Thanks

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[JKent]

Hi
Trace those wires and make sure there isn't another capacitor, either attached to the cabinet or just free-floating. In any case, the black and red PVC cap should be replaced because they tend to leak.

KLH made TWO different speakers, both called the Model Seventeen (no big deal--they made FIVE different Model Twenty-One radios!). If you search a bit you'll find some discussion about this on AK, maybe in the E-Wave thread. The later Seventeen had vinyl covered cabinets and a smaller tweeter, covered with what looked like chicken screening.

Hope this helps.
Kent

PS Found it. Check out this thread:
http://www.audiokarm...ad.php?t=219288

Edited by JKent, 14 May 2012 - 01:43 AM.

[Marigold]

Definitely, the earlier version, with the veneer.
No other capacitor. Just whats in the picture.
So I just replace the black and red cap? It sure seems like something is missing. I'm a little confused
I found many different replacement suggestions for model numbers of caps on the web. Not sure which one is correct.
Can you suggest which one I replace it with?

[Carlspeak]

You should have a 13 uF cap, a 1 ohm and a 1.5 ohm resistor and an inductor. I don't see evidence of the inductor. Chould you try to separate the components a bit and take another pic?

[Marigold]

OK. I did find, I believe another capacitor attached to the wires with twist connectors up by the woofer.
Don't I still have some missing components?

[JKent]

Carl, are we talking about the same speaker? My 17s had an 8uF cap, two 2uF caps, two 3 ohm resistors and a 7.5 ohm resistor. No inductor. IIRC, the xo is the same as the KLH 20.
Here are before & after photos, including the exploded PVC cap, and a schematic.
Kent

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[JKent]

Looks like we were typing at the same time. As far as replacements go, use film caps but the brand does not matter. Many of us use Daytons from Parts Express. Madisound sells Carli caps, which are good and inexpensive. Erseaudio.com has excellent caps at low prices, and as long as you're at it you may as well replace the resistors. You don't have to, but I think new resistors from Erse are about two bits each and it's just easier that way.
Kent

[Carlspeak]

Carl, are we talking about the same speaker? Kent

Ooops, my bad. Somehow I had NLA on the brain when viewing the OP. :-(

[JKent]

2uF:
http://www.erseaudio...v/MET25-05-2-00
or
http://www.erseaudio...l/MPX40-03-2-00
8uF
http://www.erseaudio...-Film-Capacitor
or
http://www.erseaudio...l/MPX63-03-8-20

3 ohm resistor
http://www.erseaudio...EWR10-05-3-0-PB

7.5 ohm
http://www.erseaudio...EWR10-05-7-5-PB

[Marigold]

I sorry to ask you this very lame question, but, how many of each of these do I order for two speakers.
I'm a total newbie. This is my first restoration project. If these actually work when I'm done it will be a miracle.
Thanks.

[JKent]

No problem--we were all noobs once. Look at post #6: "an 8uF cap, two 2uF caps, two 3 ohm resistors and a 7.5 ohm resistor". That's for one speaker. So for a pair, you need:
2) 8uF capacitors
4) 2uF capacitors
4) 3 ohm 10 watt resistors
2) 7.5 ohm 10 watt resistors

Do you have a soldering iron (not gun)? Can you solder? If not, you can get away with crimp connectors or even wire nuts. Do ONE crossover at a time and change just one component (cap or resistor) at a time so you don't mix up the wires. The caps are non-polar so there is not "direction" to worry about. Same goes for the resistors and as I said, you don't HAVE to replace the resistors--I just found it easier than trying to save the old ones and you're talking about a total of about $2 worth of resistors here. OTOH, looking at your photo it may be easier to leave the original resistors. Take a look and see what works for you--wire wound resistors usually don't fail, unlike the PVC capacitors that are notorious.

Here is something else that may be confusing: that Whale cap attached to the switch has 2 red wires on one end and one black wire on the other. This is just two 2uF capacitors in one body. You will replace it with two separate 2uF caps. Call them A and B. One lead of cap A goes to one lug of the switch and one lead of cap B goes to another lug on the switch, then the "other" lead from A and B get tied together. This is clear in my "new xo" photo.

Don't hesitate to ask--there are no dumb questions (there are occasional dumb answers )
Kent

[Marigold]

Great, thank you so much.
I'm going to order those components today and give it a go. At least I can't electrocute myself.
I may post some other questions when the time comes.
Thanks again for your kind help.
No I don't have a soldering iron, but I can get one easily enough.
I watched videos on how to do it.

[JKent]

if you google "how to solder video" there are lots of online instructions. This one is good:
This one too:


It's not hard. Main things are:

• Use the right tool (a pencil-type iron--not a gun)
• Keep the tip clean (wet sponge) and "tinned" with solder
• Be sure the wire is clean
• Heat the work (joint), not the solder
• Be sure the solder flows
• Keep the joint steady as you solder and while it cools--a "third hand" is handy

[Transmaster]

You might check out the Axon True Cap's at Parts ConnXion. These cap's are made by Solen. I used two 33uf 250V Axon's for the low pass on the XO's on my Polk Monitor10B's. I saved $82 dollars over the Sonicap Gen 1's
If you decide to order these cap's it is best to order them over the phone they don't really have online ordering. The service is very personal and very refreshing. I think these values are close enough, is this right JK?

http://www.partsconn..._film_axon.html

2) 8uF capacitors 8.2uF / 250VDC, True Cap, (D: 21.1mm x L: 33mm) $2.48 each
4) 2uF capacitors 2.2uF / 250VDC, True Cap, (D: 13.9mm x L: 25mm) $1.41 each

[JKent]

Yes--8.2 and 2.2 are close enough. There are lots of different opinions about caps. The Axon caps are certainly good ones and reasonably priced. The Erse caps I mentioned are similarly priced. Mills resistors are nice, but quite expensive (about $5 each) compared to the Erse resistors. But as I said--resistors may not be needed. AND there is certainly something to be said for personal service.
Kent

[Transmaster]

I replaced the resistors in the 10B XO's with Mills but I knew very well there was nothing wrong with what was there already. I was looking at Mousers and I found out Ohmite makes inductance free wire wound resistors, they are a little cheaper then the Mills.

[JKent]

I was looking at Mousers and I found out Ohmite makes inductance free wire wound resistors, they are a little cheaper then the Mills.

That's interesting. I order from Mouser fairly regularly but never bought speaker resistors. The selection is mind-boggling and navigating through the filters can be daunting. I have not been able to find non-inductive wirewound ~10 watt resistors. Can you give us a part number or a link?
thanks
Kent

[Transmaster]

Mousers has two brands that make non-inductive wire wound Vishay/Dale and Ohmite
note the Ohmite is not stocked. here is the page link the the 3 ohm 10 watt 5% non-inductive

http://www.mouser.co...sistors&FS=True

The non-inductive resistors are "Power Resistors Wire Wound Silicon Coated"

[Marigold]

I received the parts yesterday and I'm going to attempt to solder the xo's today. I ordered the parts from Erse as was recommended buy JKent. I have one speaker Jasco'ed and lightly sanded down for refinishing.
Do the drivers need to be putty'ed in for a air tight seal to the cabinet? The woofer has a white foam gasket already. I have not removed the tweeter yet. Others I have read about have used plumbers putty to seal the drivers to the cabinet.

[JKent]

Many people re-use the white foam, but it tends to become overly compressed and does not make an adequate seal. Parts Express sells very nice foam gasket tape but the cheapest and easiest to find is probably duct seal. Google "Gardner Bender DS-110N Electrical Duct Sealant" It is sold in places like Home Depot, hardware stores or electrical supply houses. A 1 pound block is MUCH more than you'll ever need, but it only costs $2.25 (at Home Depot for example). It's a bit like children's plasticine modeling clay. Just knead it in your hand and roll out some "worms". You don't need much: 1/4" diameter worms are plenty. See page 19 of the "Restoring the AR3a" booklet.

Should be no need to remove the tweeter unless that makes things easier for you.

Kent