Jump to content

HELP With RF-3 Problem


gheth54

Recommended Posts

On 9/1/2022 at 10:00 AM, gheth54 said:

I noticed the woofer that was still connected while its speaker mate was disconnected, sounded lower than all the other woofers. Early this morning I swapped it with its counterpart in the other speaker and I’m waiting for my neighbor to leave for work before I see what happens.

 

What was the outcome?

 

Pull the woofer you are concerned about, and a known working woofer. Use a multimeter, and take a resistance reading of both.

Link to comment
Share on other sites

deang; The outcome was it didn't sound like anything changed! That's what got me wondering about the condition of the crossovers.

When I first disassembled the speakers I measured each driver's resistance.

 

Left: W1: 6.6 ohms, W2: 6.0 ohms, Tweeter: 3.3 ohms

Right: W1: 5.9 ohms, W2 6.0 ohms, Tweeter: 3.1 ohms

 

None of these values seem to out of line, but is it true a driver can ohm as OK, and still be defective?

 

Thinking back, about 10 years ago I had a B&K, REF7250 amp go BANG in a big way. Hit the power button on the preamp and was greeted by a loud squeal followed by an equally loud "BANG". Along with the amp, It took out both 6" woofers of my RC-3, center and the woofer of one the SF-1s I'm using as rears. I was able to find replacement drivers and replaced the amp with a Parasound, HCA885a. Maybe there was more damage that's just become apparent?

 

 

 

 

 

 

Link to comment
Share on other sites

8 hours ago, gheth54 said:

None of these values seem to out of line, but is it true a driver can ohm as OK, and still be defective?

 

I thought I had mentioned it but it doesn't look like I did. You need to measure the inductance too. A voice coil is similar to an inductor, and if it overheated, the enamel on the wire may have melted away, which would cause a short.

Link to comment
Share on other sites

Morning, Deang, yes you did mention it, but with having to deal with project issues, it got lost in my head.

So, this morning I attempted testing the speakers inductance with my component tester.

The measures values:

 

Left: Tweeter:  .01mH, 3.0Ω   W2: .48mH, 5.7Ω  W1: .47mH, 5.8Ω

Right Tweeter: .01mH, 3.1Ω   W2 .47mH,  5.8Ω   W1: .45mH, 5.8V

I've attached a couple of pics showing the typical reading from the tester. Do these values make sense?

Also spent some time reading a couple of sites descusing inductance and speakers. I understand the math, but still not quite sure what it all means.

Typical Tweeter Reading 2.jpg

Typical Woofer Reading 2.jpg

  • Like 1
Link to comment
Share on other sites

That's great to hear!

Through work I was able to source all the Dayton and the Jantzen replacement caps. Since its already apart, it seems like a good chance to refresh and upgrade the crossover. Reminds me of doing the timing belt on my VW, since its accessible, best to also replace the water pump.

 

FYI, it was great watching Monza this morning and seeing my former employer with "Klipsch" on all the ear phones!

I'll keep this thread informed on the outcomes from the crossover refresh.

 

Thanks everybody for all your, kind, patient, and very informative help.

 

  • Like 2
Link to comment
Share on other sites

Waiting for the parts to arrive, tomorrow's my birthday (68!) so maybe another present!

While scheming out the project there's was two questions I forgot to ask.

 

I noticed the tweeters only install in 2 directions with the connections pointed towards ether side, rather than top or bottom. The woofers will go in any direction the screw holes align. Are the speakers "clocked" in the cabinet? The foam inside the cabinet only covers the back and one side. That suggests the speaker connections should be on that side so the foam guards against the wires rattling against the inner side and it encourages the wires to run away from the driver below it. Am I correct or just over engineering? LOL

 

Also, I've read on this forum to "twist" together each driver's pair of wires. I'm familiar with the advantages of doing this in network and power related wiring, but it it good practice for speaker internal wiring? If so, it'll certainly make dealing with the wiring a lot easier.

 

Thanks

  • Like 1
Link to comment
Share on other sites

Morning, billybob, I clicked on "Follow topic" at the bottom of the posts. Is that correct for "tagging" this conversation?

 

The parts arrived on Thursday and I had the afternoon free to get at the project. Besides replacing the crossover caps, I also cleaned and replaced the ferrofluid in both tweeters. The original twenty one year old fluid was thick and lumpy, like the old caked oil on an old motor.

 

The results really surprised me, I could hear the improvement as soon as the first CD stated playing. There's definitely much more "music" with the sound sharper and the instruments are more defined. Each note of EJ's piano is much more defined. Hearing the difference I realize how muddy the sound had become. Spinning Track 3 of the OST of "The Last of the Mohicans" the horns were singing again on the two fiddles. Additionally the mids and bottom end improvements has me revisiting the subwoofer crossovers and slopes. Any advice there would be very helpful. I'm not sure if the improvements are from replacing aged components, installing better components or a combination of both, but all in all, it seems like this has been the best $50 (including shipping!)  I've ever spent in audio. Thanks again for all your help.

Edited by gheth54
  • Like 1
Link to comment
Share on other sites

Yes, it just ensures you get the notification in a timely manner.

 

Well good job it appears all around. It just sounds like the parts were ready to be refreshed.

As for the oil analogy, guess you could call it lumpy or sludge that have seen. In another week or 2 of listening, tell me how they are doing.

As for the subwoofer, trial and error. Try overlapping at 120,80, and 40 hertz to get a feel for the sound.May turnout 60 is better. Had my 3s about 6 inches out from wall. Your distance may need be more.

Thanks!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...