New Caps Model 17’s

[Rick n.]

I’m new at this so I need some help. I’m needing to replace the caps in my 17’s. Which ones do I replace? Any help is appreciated. 

[JKent]

Hi Rick and welcome. I am having a little difficulty deciphering your photo but here’s what you need: one 8uF and two 2uF Per speaker. The caps, by the way, are those black cylinders. One of them we will have a single black lead at one end and two red leads at the other and the body should be marked 2+2. Replace that with two separate 2uF capacitors. Also be very careful when you replace the terminal screws. Each one has two rubber washers, one flat and one “shoulder” washer. These insulate the screws so they do not come in to contact with the metal plate.

Also take a look at the thread right below yours “Restored Model 17 Speakers”

[Rick n.]

I’m only seeing 1 black one. The others are square tan colored ones. Here another picture. 

[JKent]

Ok 

the tan things are resistors and do not need to be replaced. The red paper tube should be the 8uF

[Rick n.]

Ok, so just replace the one black tube one and the red tube one? 
And thanks for your help on this!  

[JKent]

Yes. And remember the black one is really 2 caps with a common lead on one end

[Rick n.]

Ok thanks for your help. 

[Stephen 59]

I just bought a pair of 17's this week. The cabinets are mint condition. The drivers are all intact, functioning and appear to be in excellent condition. They sound great, though a bit lighter in bass than I was expecting. My 22A's seem to have more bass extension and punch, although their woofer surrounds have already been resealed with Roy C's sealant. My question's are:

1) Should I replace the capacitors even though there is no evident need to at this point?

2) Should I go ahead and reseal the cloth woofer surrounds now or wait until I replace the capacitors or does it really matter the sequence?

Thanks!

[JKent]

1) Yes

2) Whenever 

[RoyC]

7 hours ago, Stephen 59 said:

I just bought a pair of 17's this week. The cabinets are mint condition. The drivers are all intact, functioning and appear to be in excellent condition. They sound great, though a bit lighter in bass than I was expecting. My 22A's seem to have more bass extension and punch, although their woofer surrounds have already been resealed with Roy C's sealant. My question's are:

1) Should I replace the capacitors even though there is no evident need to at this point?

2) Should I go ahead and reseal the cloth woofer surrounds now or wait until I replace the capacitors or does it really matter the sequence?

Thanks!

I just finished restoring another pair of KLH 17's. Although they were functional, measurement of the original caps showed them to be significantly out of spec. ESR was over 6 ohms for each of the 2uf caps! It is always prudent to replace KLH capacitors.

Although caps won't have a bearing on the performance of the woofers, I would wait on treating the surrounds until after the woofers are installed. The "push cone" test can then help you determine the degree of any re-treatment they may need.

There are some KLH woofer surrounds out there which have been later re-treated with stiffening material, resulting in compromised bass response. No amount of additional new sealant will be helpful in this case.

Roy

[Stephen 59]

Roy, I had already applied the first coat of the sealant based on a prior comment by others earlier this afternoon. They didn't appear to have had an application of an inferior stiffening material. So, if recapping doesn't have a bearing on woofer performance, is tweeter performance improved? 

Thanks,

Stephen 

[JKent]

13 minutes ago, Stephen 59 said:

I had already applied the first coat of the sealant based on a prior comment by others earlier this afternoon.

Sorry about the brevity of my 1st post. Was on my phone.

The most important improvement for these speakers is a re-cap. The original black and red caps are usually garbage.

Yes--the tweeters will be improved with new caps.

So how's the push test? It shpould return slowly now. In my experience Roy's goo can make a BIG difference in the woofer response. YMMV and of course Roy's the authority on this. Glad to hear there was no previous application of anything. It's terrifying what some people have used to seal their surrounds.

btw, the 22As have crappy caps too. Hope you replaced them.

[Stephen 59]

Thanks JKent. I replaced the bad caps on one of my 22A's because one tweeter wasn't functioning at all. Maybe I should've replaced all the caps at that time for the pair. I picked up the 17's this week and all drivers are functioning, though I suspect that no capacitor replacement has ever taken place. The previous owner didn't understand that the badge was screwed into the cabinet baffle and had broken both grills in an attempt to remove them, so I bought OG grill replacements from ebay. I'll test the woofer response tomorrow after Roy's dope dries. You guys have great advice for a novice KLH'er!

Stephen 

[RoyC]

21 hours ago, Stephen 59 said:

Thanks JKent. I replaced the bad caps on one of my 22A's because one tweeter wasn't functioning at all. Maybe I should've replaced all the caps at that time for the pair. I picked up the 17's this week and all drivers are functioning, though I suspect that no capacitor replacement has ever taken place.

I'll test the woofer response tomorrow after Roy's dope dries. You guys have great advice for a novice KLH'er!

Stephen 

Yup, KLH caps should always be replaced.

The sealant will remain tacky, so it never really "dries".

Roy

[Stephen 59]

Yes, I should have said "set up", not "dried". Anyhow, the 17's sound much better post woofer surround sealant. Lower bass, more punchy. They sound fantastic. Highly recommended to anyone who hasn't tried it.

Stephen