KLH Model 6 woofer frequency range.
- Thread starter RoSu_30
- Start date
GD70
Lunatic Member
Agree.
I would not hook them up to that receiver until after the repairs and at least a couple weeks testing on the Minimus 7's after the repairs. Not worth the risk ruining another set of woofers. I would even more be thinking to get another, newer amp or receiver. Becoming a member, well worth it, and helps support AK, will allow access to Barter Town, where there are plenty of exceptional pieces of restored gear for very reasonable prices.
The Six is an exceptional, iconic, vintage speaker. Worth restoring and enjoying for many years. Please post lots of detailed pice asap!
Glenn
RoSu_30
Active Member
I was pretty sure I have the correct drivers-but I am unsure about the cloth surrounds-I will take pic tomorrow that focus on the surround area of the speaker.
Thanks to your.post I finally figured out the right way to reply to individual posts-Leaving the 6's alone until I get the Sherwood repaired or not-
RoSu_30
Active Member
I agree with your plan-I like the Sherwood because of its tube like sound but not at the cost of it being unreliable-and it's better to experiment on the 7's than the 6's. I hope to be able to keep them more so than the receiver. Now I have to find out how to join Barter Town. Thank you.
RoSu_30
Active Member
I hope these are helpful-but still not clear what or where the surround is-because I think I have the wrong idea of what a surround is-
I thought the surround was a foam type ring that fit between the rim of the speaker and the "seat"
apparently it's the yellow padding around the outer edge-not sure what the "U" refers to-in that case my surrounds are fine-
I thought the surround was a foam type ring that fit between the rim of the speaker and the "seat"
apparently it's the yellow padding around the outer edge-not sure what the "U" refers to-in that case my surrounds are fine-
GD70
Lunatic Member
Becoming a subscriber is easy. Go to the home page, click the Subscribe button, and pay. Done! A great way to start the New Year!
It's an annual subscription.
swechsler
Frog Whisperer
It's U-shaped when viewed on edge, which you can't do without cutting it apart, but don't worry, you've found it. It's what enables the woofer to move in and out while keeping the cabinet sealed.
RoSu_30
Active Member
Thank u-I have a habit of asking about something and then finding it on my own-
it appears very pliable w/o any tears thankfully-thanks-again-
fill35u
Super Member
Anytime somebody claims something has been repaired/restored/refurbished/tested, there should be a very detailed written list of what was replaced with what, what was adjusted/tested/measured and what the adjusting/testing/measuring results were.
RoSu_30
Active Member
I agree with you in theory-but I've never met anyone who would do be that meticulous-I have ask for that information and all I got was a dirty look-There are only 3 people around here that repair hi-fi equipment, and I'm not one of them, the other two are less than honest, and the person who repaired the Sherwood was my last hope-It did work for a few weeks w/o issue until the repaired problem came back-Taking it back to him now-we'll see how it's handled-
Tim D
Super Member
The surround is the orange part that joins the speaker cone to the metal basket in your picture. They are made of cloth and seldom fail. It is circular because the cone is circular. The reference to "U" is because of the ditch shape of the surround is like a "U" shape. That "U" shape gives the surround some slack so that the cone can move in and out to the music.
Per the photos, your surrounds look to be in good shape but due to the age they will need to be treated with a rubberized goo. That goo is a sealant that was applied at the factory to ensure that air is no passing through the surround (and dust cap too). After 50 or more years the sealant would definitely need to be re-applied.
So why did you think you needed new surrounds? What part do you think has gone bad that you thought was named "surround"?
Per the photos, your surrounds look to be in good shape but due to the age they will need to be treated with a rubberized goo. That goo is a sealant that was applied at the factory to ensure that air is no passing through the surround (and dust cap too). After 50 or more years the sealant would definitely need to be re-applied.
So why did you think you needed new surrounds? What part do you think has gone bad that you thought was named "surround"?
RoSu_30
Active Member
I thought I made why I thought I needed new surrounds clear in an previous post-but I may not have-
1) that right cone flexes in more than the left speaker cone and I thought it may be from the loud static from the receiver-
2) but more importantly-I had the wrong idea what/where the surround is and where it's located-I couldn't find it because I didn't know where to took-
3) lack of knowledge-but I'm learning now-
bowtie427ss
Lunatic Member
130 bux at your nearest Target:
dly66
Addicted Member
I got an S-7200 as-is off the shopgoodwill site a few years ago and was making weird wave noises in the background when I got it that soon became static crackling type noises. Using freeze spray that indicated the 2SA666 differential pair was the offender on the bad channel. Replaced the pairs on both channels with KSA992 and problem gone.
Recapped and replaced some transistors in the S-7200, the 2SC693Fs on the tone board were generating a good bit of white noise. Replaced all four with KSC1845 if I remember. Nice sounding receiver, one of the favorites in my collection. No relay or protection circuit on it, like many uses fuses.
Bought an untested (no cord) SX-636 from binkman cheap saw 3 2SA726 and what I guess was an NTE replacement replaced those and the 2SC1451 and ended up with a nice sounding receiver that works well, probably some recapping is due. He said he tested it and got a lot of crackling and put it on CL. I replaced those transistors and put a cord on it surprised when I brought it up was stable and worked well. Has issue with AUX thinking it may be a bad cap but tuner works well.
A few weeks ago picked up a badly crackling Sansui 771 when person demoed it the noise overwhelmed the tuner output even tripped the protection relay periodically. New differential pairs (2SA726s again) and DC stable and no noise. Been enjoying the 771 over the last 2 weeks.
With what voltages I saw out of the 771 when I put DVMs on the outputs in DC voltage mode before transistor replacement its possible a woofer got damaged. He may have only one bad. Then again the voltages in that situation often are not that high so he may be okay. On the 771 one channel was getting much higher voltages than the other, one stayed under a few hundred millivolts other went to a volt or two.
You can push the cones to the outer ranges just using a battery (AA, AAA, C, D whatever is handy and two wires) swapping polarity will change direction. Do to both and see if the cone moves in and out the same or different. If one has displacement symmetrical it should be good. Also carefully push cone in and out feeling for voice coil rub. Overheated voice coils can drag which you can feel. Comes from a simple DIY speaker building check to get an idea of the damping of the woofer in the cabinet.
Recapped and replaced some transistors in the S-7200, the 2SC693Fs on the tone board were generating a good bit of white noise. Replaced all four with KSC1845 if I remember. Nice sounding receiver, one of the favorites in my collection. No relay or protection circuit on it, like many uses fuses.
Bought an untested (no cord) SX-636 from binkman cheap saw 3 2SA726 and what I guess was an NTE replacement replaced those and the 2SC1451 and ended up with a nice sounding receiver that works well, probably some recapping is due. He said he tested it and got a lot of crackling and put it on CL. I replaced those transistors and put a cord on it surprised when I brought it up was stable and worked well. Has issue with AUX thinking it may be a bad cap but tuner works well.
A few weeks ago picked up a badly crackling Sansui 771 when person demoed it the noise overwhelmed the tuner output even tripped the protection relay periodically. New differential pairs (2SA726s again) and DC stable and no noise. Been enjoying the 771 over the last 2 weeks.
With what voltages I saw out of the 771 when I put DVMs on the outputs in DC voltage mode before transistor replacement its possible a woofer got damaged. He may have only one bad. Then again the voltages in that situation often are not that high so he may be okay. On the 771 one channel was getting much higher voltages than the other, one stayed under a few hundred millivolts other went to a volt or two.
You can push the cones to the outer ranges just using a battery (AA, AAA, C, D whatever is handy and two wires) swapping polarity will change direction. Do to both and see if the cone moves in and out the same or different. If one has displacement symmetrical it should be good. Also carefully push cone in and out feeling for voice coil rub. Overheated voice coils can drag which you can feel. Comes from a simple DIY speaker building check to get an idea of the damping of the woofer in the cabinet.
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infullview
Super Member
It's possible you have a short from the voice coil to the frame of the speaker that could overload your amp. Gently and slowly push the cone down, and listen for any rubbing noise as the cone travels up and down.
RoSu_30
Active Member
Amazing pics-a very nice job-
Paragraphs 1 through 5 are a bit over my head But I can relate the last one-The speaker with the most static also has a noise when gently pushed up and down-I didn't know what made the noise but it may be what you suggested-From the voice coil-which I understand can be tested-The Sherwood is out for repairs-when it's done the speaker resistance, caps, and VC will be tested.
Thanks for all the help and the effort it took to offer all that information-
RoSu_30
Active Member
The term Voice Coil keeps coming up-I do get a "rubbing sound" from the speaker that has the most static-The amp just got dropped off for repairs-When It's done both speakers will have their resistance, caps and VC checked-Hopefully that will answer a lot of unknowns-thank you-
RoSu_30
Active Member
Hey, thanks gonna go look it up-nice pic-130 bux at your nearest Target: