Have an old Klipsch 4.1 speaker system? Did it die? I bet you can fix it!

TOOL1075

Gawd
Joined
Aug 29, 2002
Messages
690
Updated with Crappy Photo Guide Tour


I thought I would post about something I fixed last week.

So, while I was at work, my wife needed a power outlet, so she unplugged my Klipsch 4.1 speakers from the surge protector (not the V2.400 version, but the newer revision that Klipsch made right after that. all this is applicable to both though, as all klipsch really changed was the crossover points for the satellites).

Long story short- wasn't muted, so when she plugged it back it- speakers no worky no more.

These aren't the best speakers, but for casual computer music and gaming use, they're great (and I've had them for a pretty long time).

So I opened up the subwoofer (to get to the amp) and saw that there were two resistors that had some problems:

R12 and R26. (680ohm and 47k ohm, respectively).

Note: these first two photos are not my photos- I found them elsewhere. (My Photos are now added at the end of the post, below) They give you a good idea of what has happened though. The R12 picture shows the zip tie. My zip tie was completely melted, and broken through! But, the R12 was still working. My R26 was way worse than shown in the second picture though...


R12 is the gray resistor.

R12 heated up like a bitch in heat, and melted a zip tie that was used on the board for structural support. But, after measuring the resistance with my DMM, 680ohm on the button- so this wasn't the problem. Sure was scorched though...


R26 is the brown resistor.

R26 basically exploded. The shell of the resistor was cracked, fragmented, and the current path was completely blown open.

Well, using my trusty soldering iron, solder, some desoldering braid, and some new resistors from Digikey, I replaced R26.

My speakers work again!!!

Here is a link to some rough schematics that some guy made, if you are interested:

http://www.thompdale.com/bash_amplifier/bash_amp.htm

By the way, I think the original R26 was a 1W resistor, so I replaced it with a 3W lol. I also bought some replacement resistors for R12, just in case it decides to go later.

I hope this helps someone out there. (these two resistors seem to be a common problem with this particular amplifier)


Crappy Photo Guide Tour:


Photo 1: Unopened subwoofer box. The screws you need to remove are circled in red.

01unopenedsubwooferfg4.jpg




Photo 2: Subwoofer box open. Careful now, don't rip it open so fast. Look underneath the board, and disconnect the speaker leads from the board.

02unscrewedandopenedvs4.jpg




Photo 3: Insides of the subwoofer enclosure, with the amp no longer in place.

03plateampdisconnectedabb2.jpg




Photo 4: Entire plate amp assembly.

04viewofentireplateampafw1.jpg




Photo 5: The new R26 I put in place (47k ohm). Notice its large, manly size. That's because it has a 3W power handling capacity. The old one only had a 1W capacity. Arrows indicate where I had to bend the resistor leads to fit it in the PCB holes :)

05newr26inplacenj5.jpg




Photo 6: Rear side of the PCB (the side you solder on). Yeah, I used a tad too much solder. no harm done.

06newr26inplacerearsidebw1.jpg




Photo 7: Old, destroyed R26 (47k ohm, 1W).

07oldr26cb5.jpg




Photo 8: Old R12 (680 ohm) still going strong. Notice the charred PCB? Excessive heat melted the zip-tie that was connected to the board at the red circled hole. The black stuff is from the burning of that plastic zip-tie.

08r12stillworkingnk9.jpg




Photo 9: Old fuse, still intact. If only this were the common failure point! lol fucking klipsch....

09fusemb2.jpg




Photo 10: One of the rows of MOSFETS. Mine are fine, but I think I once read about someone having problems with those, and them fixing it.

10mosfetsrow1hy6.jpg




Photo 11: The other row of MOSFETS.

11mosfetsrow2oh5.jpg


 
IIRC, one of the issues with ProMedia power supplies crapping out is under-rated resistors like this in the amp in some sort of Class A circuit. I was pretty sure that the amplifier design as Class B (push-pull) but I distinctly remember someone stating that these parts overheat regardless of power consumption and, in actual fact, fail less often when in use because the movement of the sub circulates air in the sub chassis. Instances of failures were higher for ProMedia systems left on but playing no audio. Go figure.

Thanks for posting specifics. It seems that most people who learn specific components and values decide to start an online ProMedia repair business instead of sharing with the community.
 
Hey man- no problem. I just want to save some people out there some money!

Yeah, the resistors definitely didn't have enough power handling. I replaced them with 3W versions, and if they ever blow, I guess I'll go to 5W, since the leads will still be the same diameter, and I will still be able to solder them to the board lol.

oh, and by the way, to the people with dead speakers:

by "dead," I mean the LED near the "mute" button doesn't turn on, and you have no sound- nothing. This might work for other failure symptoms too- so you might as well unplug the sub, open it up, and check the values of those resistors anyway!
 
update -

the results speak for themselves.

After solid use of the speaker system over the past week, including a lot of music and gaming, it sounds as good as it did when it was brand new. :cool:
 
Hey guys!

Boy, I am glad to have found this thread (and the other related ones in this forum). I have the promedia 2.1's and have been having problems with them for probably almost a year now (I've owned them for 4+ years).

My problem is the subwoofer barely ever works anymore. Initially, it started off with the subwoofer not working for a minute when I first turned the speakers on, but after it "warmed up," it would work. Then, it took longer and longer to "warm up." Now it rarely works, if ever. My satellites work fine and always have, my control pod is fine, and my DIN plug is fine. This leads me to believe it's an internal amplifier or transformer problem, but I'm not an electrician (I took an ECE class back in school, but that's about it; I'm an ME by trade.) and I have really no idea what's going on inside.

I took the amplifier out and looked at everything, but I didn't see any obviously burnt resistors or capacitors or the like. I did take a bunch of pictures, and I am going to post them here, along with the request that if anyone has any ideas or sees anything funny in the pics, please let me know. I do have access to a soldering iron and my technical aptitude is decent, so any suggestions are appreciated. I'm just wondering if it has somethign to do with all that green goop that looks like it melted all over the place.

The pictures start out from the bottom of the amp (when I refer to bottom, I mean the vertical bottom, as the amp is mounted vertically in the sub enclosure). You can see where the A/C input is, as well as the fuse in the first pics. The second pic (3008) would be looking "uphill."

Thanks a bunch,
-Dirk



 
from the same guy's page I linked to for the 4.1 systems, here are the 2.1 system schematics:

http://www.thompdale.com/bash_amplifier/2-1/2-1_bash_amp.htm

I'm not sure what the problem is. The symptom you describe seems to be something I've heard about happening before, but I don't know what it is (I'm a CE (SE) by trade lol - not a EE. I just know enough about electronics to be dangerous)

I recommend you post on an audio forum, specifically one dealing with home audio amplifiers, or the like. (electronic components working only after "warming up" can be indicative of a loose connection, or something else. and the "something else" is probably a well-known thing that amp guys would know)

you could also start by verifying your fuse is okay, as well as some of the bigger resistors. You just need a multimeter. I'm assuming the fuse is fine....

I'll do some reading and see if I can come up with anything.

edit: oh, and something to add. I bought the 4.1 system a while back, when Klipsch was just getting into the "multimedia" side of things.

Klipsch should have stuck with what they have always done best - loudspeakers. They suck at building amplifiers lol
 
You are tempting me to grab some "broken" 4.1 Promedia's! Do you think it is just a simple resistor issue everytime or were you just lucky?

Somewhat OT: Why did Klipsch stop making surround computer speakers?
 
well, it's definitely a common failure point. I've seen numerous instances in which failed R12 or R26 were the cause of the system failure.

Symptoms include:

Dark LED light - i.e. no power lol

I've also seen cases where a different component failed (like a MOSFET for example)- but it's mainly been those resistors. (at least out of the cases that have been reported on internet forums)

Why did they stop making surround computer speakers? You know, I'm not sure. Oh, wait, yes I am. Klipsch sucks at building amps! lol I guess the failure rate of their surround systems was higher than acceptable, and they didn't want to fuck with it anymore. Their customer service is abysmal.

I speculate that the 2.1 systems have a lower failure rate.
 
Mine just died two days ago, after 10 years. how do I open up the sub, and it is safe to start removing surface level components from the PCBs once I get it open? I have a multimeter to check for a charge in capacitors (so I don't die).
 
Mine just died two days ago, after 10 years. how do I open up the sub, and it is safe to start removing surface level components from the PCBs once I get it open? I have a multimeter to check for a charge in capacitors (so I don't die).

First, please unplug the system (of course lol).

I'm assuming your system is a 4.1 model?

There are screws on the back of the subwoofer, securing the plate amp to the wooden enclosure. Unscrew those screws, and you can pull the plate amp out.

Be careful, and do not pull it out very far without first disconnecting the leads from the subwoofer drivers from the PCB. You can simply pull off the connectors. There are 2 connectors to the PCB for the subwoofer drivers.

I wouldn't worry about getting hurt, just follow all the basic safety rules. (i.e. don't put a capacitor in your mouth, etc lol)

My bet is that you have a blown resistor. Check the usual suspects (R12 and R26). Note that just because they looked burned doesn't mean they aren't working.

My R12 is really scarred and burned up, but it still is showing the proper resistance, and still works. My R26 was the problem.

Be sure to check the values with your DMM. Also note that you might not be able to get a proper reading, depending on the oxidation and/or corrosion on the resistor leads. You may have to test the resistance at the lead-to-pad connection on the PCB. Basically what I'm saying, is that you need to be careful measuring the resistance, so you don't get an incorrect reading.

(it's possible to think the resistor is blown when it really isn't, just by not getting good contact to the leads of your DMM)

edit: If it's a blown resistor, and you are going to replace it, replace it with a resistor of the same value (ohms) but of higher power handling capacity (watts). The new one will be bigger, and you might have some trouble fitting it to the board.

If this is what you end up doing, let me know and I'll take some pictures of what I did. In fact, when I get home from work today I'll open up my amp and take some pictures.
 
Yes, they are:

Klipsch ProMedia v2 4.1's

This is very good news, and thanks for the little write up. If I can get these fixed, I'd much rather do that. I have, over the last 10 years, become very attached to them, and would rather fix them than have to get new ones (although I was planning on it relatively soon, just not now). Thanks again. Hopefully I'll get to looking at this, this weekend. I'll be sure to reports back.
 
from the same guy's page I linked to for the 4.1 systems, here are the 2.1 system schematics:

http://www.thompdale.com/bash_amplifier/2-1/2-1_bash_amp.htm

I'm not sure what the problem is. The symptom you describe seems to be something I've heard about happening before, but I don't know what it is (I'm a CE (SE) by trade lol - not a EE. I just know enough about electronics to be dangerous)

I recommend you post on an audio forum, specifically one dealing with home audio amplifiers, or the like. (electronic components working only after "warming up" can be indicative of a loose connection, or something else. and the "something else" is probably a well-known thing that amp guys would know)

you could also start by verifying your fuse is okay, as well as some of the bigger resistors. You just need a multimeter. I'm assuming the fuse is fine....

I'll do some reading and see if I can come up with anything.

edit: oh, and something to add. I bought the 4.1 system a while back, when Klipsch was just getting into the "multimedia" side of things.

Klipsch should have stuck with what they have always done best - loudspeakers. They suck at building amplifiers lol

Thanks for the reply. On the suggestion of posting on audio forum that deals with amplifiers - got any suggestions? I've done a search, but if you know any that are particularly good, I'd love to hear about them. The fuse is definitely fine though; the speakers always power up fine, and the satellites always work ... its just the sub, unfortunately.
 
Thanks for the reply. On the suggestion of posting on audio forum that deals with amplifiers - got any suggestions? I've done a search, but if you know any that are particularly good, I'd love to hear about them. The fuse is definitely fine though; the speakers always power up fine, and the satellites always work ... its just the sub, unfortunately.


This forum would definitely be a good place to ask.

I know I said I'd open up the sub now (I'm home from work) but I'm so lazy... and it's Friday lol...

I gueeess I'll open it and take some pics :p

stand by...
 
I took pics and updated the first post.

Yes, the camera is crappy. And yes, I'm not a photographer :p

I hope the photos help.
 
Here's what I found when I opened mine up. the resistor is awfully crispy, the fuse is still good. the large capacitor seems to have leaked some.

IMG_1894.jpg

IMG_1899.jpg
 
yeah, my capacitor is like that too - it's probably okay.

So, is R12 not working? It doesn't look like its blown. You measure it?

What about R26?

edit: oh, yeah, your R26 is done for I think. Replace it, and you're good to go. (but measure it first, just to make sure lol)
 
I have a multimeter, but I've only ever used it to measure voltages. How do I measure ohms? It has the settings for it, but I don't know how to do it properly.
 
okay, set it to measure resistance.

R26 is 47k ohm. (47,000 ohms)

So, set your multimeter to measure resistance, and turn it to a resistance ABOVE 47k ohms. Mine has settings for:

200
2k
20k
200k
2M
20M

To measure a 47k ohm resistor, I would turn it to 200k.

If there is infinite resistance (meaning the resistor doesn't work) then the resistor is bad.

Test R12 first. For R12, I would turn my meter dial to "2k" because 680ohms is less than 2k, and greater than 200.

I'm not sure what settings your meter has, but this should help I think.


edit: Your meter will probably read "infinite" or "1" if:

A. The resistor is blown open

B: You aren't getting good contact

C. Your scale is set too low

If I measure a 47k ohm resistor with my DMM, and I have the dial set to "200k," it will read "47."
 
R26 reads 489 with the dial set on 200k, so I guess that's 489k ohm?
R12 reads 661 with the dial set on 2k, so that should just be 661ohm?

Anything else to check? Fuse looks good, and I don't see anything else.
 
R26 should be reading somewhere around 47k ohm if it's okay. Are you sure you're not getting a reading of 48.9k ohm? (48,900 is close to 47,000)

If you are really getting a reading of 489k ohm (489,000), the resistor is bad, and you need to replace it.

R12 reading at 661ohm is close to 680ohm, so I think you're okay on that one. I didn't think your R12 was bad... it shows heat damage, but many (including mine) showed that and were still okay.

Measure R26 again. I have a feeling it's blown. In the picture, the outer shell was cracked, correct? Mine was cracked like that, and it was blown. (and measured infinite resistance, or something really high- I don't remember)
 
You were right. R26 measured 48.9k ohm, not 489. Hrmm, now what!?
 
You were right. R26 measured 48.9k ohm, not 489. Hrmm, now what!?

I was afraid of that...

Well, there are a bunch of possibilities, but I think we can narrow it down to 2:

A: R26 is too much out of tolerance, and it's the component you need to replace.

B: Another component in your DC-DC converter is broken.

I'm not sure about option A... so, before you go replacing R26, you should consider option B.

I'm thinking it's your DC-DC converter, because your Digital Converter common failure point (R12 in the digital converter) is okay. You can see R12 here:

http://www.thompdale.com/bash_amplifier/flyback_voltage_supply-563x322.gif

and here:

http://www.thompdale.com/bash_amplifier/4-1/4-1_converter_994x752.gif


So, let's take a look at the DC-DC converter:

http://www.thompdale.com/bash_amplifier/dc-dc_converter-722x444.gif

or

http://www.thompdale.com/bash_amplifier/4-1/4-1_dc-dc-974x606.gif

You can see R26. It is shown as 47k ohm, 1-Watt, or 2-watt. Those schematics are for the V2.400 and the 4.1 system, respectively. Mine was blown, so I replaced it with a 3-watt. The guy on that website replaced his with a 5-watt. We're not sure about your's.

There are other common failure points in the DC-DC converter.

Go here: http://www.thompdale.com/bash_amplifier/4-1/4-1_bash_amp.htm and scroll down to the DC-DC Converter section.


R27 in the DC-DC Converter

The author, like other people, describes his R27 resistor has failed. The V4.1 schematic shows it as a 4.7-ohm resistor. The V2.400 page calls it a 5-ohm resistor, achieved by putting two 10-ohm resistors in parallel. Measure whatever is there, and make sure it is showing close to 5 ohms (in the case of 1 resistor) or 10 ohms each (in the case of you having two resistors there to do the job).


R1 and R2 in the DC-DC Converter

These resistors are both 475-ohms. Measure them.

And, before you measure this stuff, read this page:

http://www.thompdale.com/bash_amplifier/bash_amp.htm (which talks about the v.2-400 version of the speakers, and has basically the same components, except for the control pod stuff)

And, of course, that page links to this (for the newer version of the 4.1 system).

Be sure to post back if you're having trouble locating any of these components, and I'll open mine again and try to help you out.

Again, be sure to read this page though... because they talk about how they fixed stuff, and it just gives you a general overview of what is going on. The 4.1 page is VERY good, because the guy explains what everything does.
 
Be sure to post back if you're having trouble locating any of these components, and I'll open mine again and try to help you out.

A lot of this is admittedly over my head. However, being able to locate R26 on the PCB sounds like it would be a good start, and I can't seem to find it.
 
you mean R27?

edit:

With some quick google-fu, I found this:

http://forums.klipsch.com/forums/p/88023/891180.aspx#891180

In the last post of the thread, on page 2, the guy talks about what he did to fix his.

I apologize, but I don't have time right now to open mine up and locate the resistor(s) and take pictures, but I may have some time tonight.

I think the label for R27 is under the resistor, so it's not visible from above.
 
I think this is R27. The color bands may be dis-colored... I'm having a problem reading them....

r27qm3.jpg


I think it is 4.7 ohms, as the schematic said. (which would probably make sense, given that the older version of the amp has two 10ohm resistors in parallel, which would equal 5 ohms. 4.7 isn't 5, but it's close enough.)

Looking at the color bands, it is Yellow - Violet - Gold - Gold

Which is

4.7 ohms, with a 5% tolerance.

I gotta run, but I'll be back. I'm going to try to find R1 and R2 for you as well.
 
Okay man, I found R1 and R2.

Their color bands are:

Yellow - Violet - Green - Black - Brown

That's 475 ohms, just like the schematic says :)

Here's R1:

r2js0.jpg



and here is R2:

r1ys3.jpg



So, let's recap here....


You tested R12 on the Digital Converter, and got around 680 ohms, right?

You tested R26 on the DC-DC Converter, and got around 47k ohms, right?

Now:

1. Test R27 on the DC-DC Converter. It should read around 4.7 or 5 ohms.


2. Test R1 and R2 on the DC-DC Converter. They should both read 475 ohms.


Now, you might have to take apart the assembly a bit more to reach in and test R27....


Post back with any problems you may have and I shall do my best to help.

Keep in mind, you aren't always able to tell whether a resistor is bad by looking at it!


oh, man, I almost forgot....

here's a good resistor color-band identifier for 4, 5, and 6 band resistors I found with google just now:

http://www.samengstrom.com/nxl/10116/5_band_resistor_color_code_page.en.html

Edit: To confirm, I just measured R2 and it was 475.
 
Great thread, thanks!

I have the Klipsch 4.1 setup and have been happy with it for years. Sure there are better speaker/sub/amp combos out there but the Klipsch Promedia setup is/was perfect for my needs. Most people are probably like myself and have other systems for music/home theater.

Getting to the point...I awoke yesterday morning to hear static coming from all 5 speakers! The only way to eliminate the static was to kill the power, pull the plug. After doing some research and wrenching I seem to have the same as many others and this thread address.
Again, thanks to the original poster for the time and effort that has gone into this.

My question... would you be willing to put together a shopping list of resistors that fail and a vendor that carries them all?

My R26 is cracked but reads ok, my R12 is scorched but reads ok as well. I have power just immense amounts of static, music can be heard through the speakers although at a much lower volume than the static.

My plan is to replace the R26 first and then go from there replacing others until it's fixed.
If anyone has a complete list of resistors and recommended replacements It would be greatly appreciated.

Thanks in advance.
 
<snip>

My question... would you be willing to put together a shopping list of resistors that fail and a vendor that carries them all?

<snip>

No problem - I'm happy to help.

Well, here is a partial screen-capture of my invoice from Digikey. (they're a great place to get all kinds of electronic components from. I, along with many other people I'm sure, would recommend them):

digikeyinvoiceqr4.jpg


You can see that I bought some 680ohm resistors (for R-12, even though mine still works, I wanted to have them just in case).

I also bought some 47k ohm resistors (for my R-26 that went bad).

I had to buy 5 of each, because that's the minimum purchase amount for those items.

You can see that I also bought some de-soldering braid, cause I didn't have any.
 
I usually order from Mouser but Digikey looks like they have a good selection as well.

Thanks for the info on the R26 and R12 resistors. I was thinking of ordering R1, R2 and other replacements as well if these also are problem areas.

I hate waiting and paying ridiculous shipping charges so I tend to stock up on things like this.
 
Okay man, I found R1 and R2.

Their color bands are:

Yellow - Violet - Green - Black - Brown

That's 475 ohms, just like the schematic says :)

Here's R1:

r2js0.jpg



and here is R2:

r1ys3.jpg



So, let's recap here....


You tested R12 on the Digital Converter, and got around 680 ohms, right?

You tested R26 on the DC-DC Converter, and got around 47k ohms, right?

Now:

1. Test R27 on the DC-DC Converter. It should read around 4.7 or 5 ohms.


2. Test R1 and R2 on the DC-DC Converter. They should both read 475 ohms.


Now, you might have to take apart the assembly a bit more to reach in and test R27....


Post back with any problems you may have and I shall do my best to help.

Keep in mind, you aren't always able to tell whether a resistor is bad by looking at it!


oh, man, I almost forgot....

here's a good resistor color-band identifier for 4, 5, and 6 band resistors I found with google just now:

http://www.samengstrom.com/nxl/10116/5_band_resistor_color_code_page.en.html

Edit: To confirm, I just measured R2 and it was 475.

R27 measures 1ohm...I'm guessing that's not good. It never changes, not matter where I masure it from (surface of PCB or back). R1 and R2 are spot-on with what they should be.
 
Hey Tool,

I've checked all the resistors you've mentioned and ever went ahead to change the first two you mentioned just incase..

But still I have a crap load of static coming out of my speakers and sub .. Any ideas? :(
 
I'm not really sure what is causing your static.

Have you isolated the problem to a certain component? I posted this thread to help people that had the same problem as me (no LED light on, no sound).

Over time, I guess the thread has evolved into an all-encompassing repair thread. When I have time, I will try to research your problem. I apologize that I can't be of more help at the moment.

If you can, use the schematics to test all the components you can, and try to isolate the problem. Perhaps someone with your particular problem (static) can chime in and give you some help on where to start.

I know that there are some trying to make money off of the problems with these speakers by offering to fix them.

There's nothing wrong with that, but they hoard the information, so they can make a profit. I guess that's business....

Again, I apologize that I can not offer any immediate assistance other than the above advice.
 
I just noticed that Dale Thompson has used some of my photos on his schematic/repair pages:

http://www.thompdale.com/bash_amplifier/4-1/4-1_bash_amp.htm (scroll all the way down)

See, this is good.

This is information sharing.

Hopefully, enough people will post enough information about these speakers, and we get some kind of "central-repository" of info going- so it will be easier (and cheaper) for everyone to keep their speakers working for the long term.

edit: I emailed Dale, and maybe he can chime into this thread, and help out too.

The more the merrier.
 
Hi,

Would someone be able to explain to me how I can remove the amp from the Ultra 5.1? I took out the 12 perimiter screws, but I there is no groves so I can pull out the amp. Maybe it''s just because I forgot to remove some screws, but I don't want to take them all out since I don't know if the amp will fall off the plate

Thanks
 
emichon-
I got the 5.1 Ultras. you remove all the screws and you need to get a good grip and just lift one side up a bit and then lift the entire thing out. Don't forget to unplug the two leads too.

I had bought a 2nd set of 5.1 ultras but the sub powers up and blows the fuse immediately, giving off smoke and a burning smell. I guess it's an amp problem? Is there any way I can fix it for myself? I've already sold the 2nd set of speakers and just the sub and control pod are sitting and taking up space. Would love to see if I could get it working maybe? Or if anyone wants it?
 
I have the promedia 5.1, and my problem is different from others here, and in the other klipsch repair thread. I have traced it down (not hard when the cap blows out all over the board), it is C530, under the transformer on the dc/dc board:



It resides basically here (the striped one):




I have had no luck finding the value of this piece for replacement. The piece itself is ruined, it cracked apart when i touched it, so no help there. I am also not sure on the one next to it, it might just have some black on it from the blowout of the definitively ruined cap. Either way, maybe one of you has the info I need? I tried the schematics here:

http://www.thompdale.com/bash_amplifier/5-1/5-1_bash_amp.htm, but the ones for the 5.1 amp are incomplete.

Thanks in advance...
 
Great thread, thanks!

I have the Klipsch 4.1 setup and have been happy with it for years. Sure there are better speaker/sub/amp combos out there but the Klipsch Promedia setup is/was perfect for my needs. Most people are probably like myself and have other systems for music/home theater.

Getting to the point...I awoke yesterday morning to hear static coming from all 5 speakers! The only way to eliminate the static was to kill the power, pull the plug. After doing some research and wrenching I seem to have the same as many others and this thread address.
Again, thanks to the original poster for the time and effort that has gone into this.

My question... would you be willing to put together a shopping list of resistors that fail and a vendor that carries them all?

My R26 is cracked but reads ok, my R12 is scorched but reads ok as well. I have power just immense amounts of static, music can be heard through the speakers although at a much lower volume than the static.

My plan is to replace the R26 first and then go from there replacing others until it's fixed.
If anyone has a complete list of resistors and recommended replacements It would be greatly appreciated.

Thanks in advance.

I have the exact same symptoms. Any chance you were able to resolve the problem? If so, what were the faulty components?
 
I'm debugging my Klipsch 4.1. Neither R12 nor R26 is discolored, and both measure close to their nominal values. Never the less, the LED on my control pod doesn't light when the speaker ikon switch is in either the in or out position, and no sound come from my speakers.

The voltage into my DC-DC inverter 640014 REV 6 as in this diagram
bash_block-714x539.gif


is 166 VDC, and the voltage between F01/W3 and F02/W4 on the Digital Converter 640036 Rev 5 is 54.1 VDC. Not the nominal 60 VDC, but probably OK.


Next, I opened up my control pod. Unfortunately, my control pod is a different revision than the pod in the diagram
2-400_contol_rev7-710x550.gif
described on its parent page: http://www.thompdale.com/bash_amplifier/bash_amp.htm.

Here are pictures of my pod:

ControlPodTopside.jpg


ControlPodUnderside.jpg


My R33 measures 2.67K but my R34 seems to be missing! From the trace on the underside, it seems that R33, the LED, and R34 should be in series. I don't see how the LED can possibly work without an R34 in place. I'd appreciate it if someone who has the same control pod version as me could pass on the value of R34, assuming that mine has fallen out.

I have to confess, I don't understand the design strategy of using two resistors in series with the LED. It just doesn't make any sense. A single resistor should be sufficient to limit the current through the LED, but you can see the traces yourself in the pictures.

I've looked all over the pod circuit board, and I don't see anything like the two 15V zener diodes that regulate the the +/-15 VDC supply to the TL082 and TL074/TL084 op amp chips on the Thompdale www site pod. That circuit makes sense to me. Unfortunately, my own doesn't. Suggestions?

Thanks, -Joe
 
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