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Klipsch 5.1 amp dead. anyone have a DIY repair guide?

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Cow Hunter

Registered
Joined
Dec 18, 2002
Location
RI, USA
this thread probably wasn't reaching the right crowd in the sound section so i am reposting it here

my klipsch promedia 5.1 speakers all of a sudden turned into 0.1 speakers a few days ago as all 5 satellites stopped working and only the sub was producing any sound. I have looked on several message board and it seems this is a common problem of the amp dieing due to overheating and i also hear stories of a few people who will repair it for money or sending it back to Klipsch for repair, but i was wondering if any of the hardcore modders here had ever repaired their own or if someone had put together a guide on how to repair a broken one.

thanks
 

Pic of the top how it sits in the sub box


close up pic of the top circuit board


main power input goes to the top right circuit board, then to bottom right board laying flat, then to the bottom left board. its in this bottom left board that i imagine the problem lies. you can see 2 sets of power cables comming out of it, 1 set looks like it powers 1 speak and the sub, the other chains to each of the remaining 4 amps. the problem is i can hear the sub working, and the other speakers come in and out

Here are some closeups of what i think is the problem area, although they are partially blocked by what look like heat spreaders






if you would like any close up pics of other sections of the board let me know
 
thanks for the info, although i would have liked to have seen at least one person respond saying that also solved his problem. the fact that my sub and control unit still got power means the power leaves that PCB and goes on the the rest, so i would assume that isn't my problem. I did try doing a continuity test on the unit though and it didn't have continuity between its 4 feet, but i don't really understand what it does so maybe thats normal

i was about to post some more pics when i saw your reply incuding one right around that part in question.


you can see the glue on the components is totally burned off


but underneath the traces look good still


only points that looked closed to burned on the underside of this board below


i removed one of the heat spreaders(which i know is going to take me forever to get back on) to give a better view of the components and i circled the area corresponding to the other circle above


one last picture for you
 
when u turn it on does it click or not
if you read the whole thread to site i linked u will see that its the same problem that you have
 
morpheus6d9 said:
i registered just to help you out lol
http://www.hardforum.com/showpost.php?p=1028862277&postcount=89

instructions on how to fix your amp

That's good information, if my Promedia goes on the fritz, this information is the first thing I'll be checking. Thx for registering and sharring this tip.

PS, I've noticed the amp's faceplate is a bit warm and has always been hot. I'll be taking it apart this week and modding it a bit to include better heatsinks, better thermal paste (although I'll be using Arctic Silver adhesive), then lastly going to figure out how I can add a silent fan to the inside. I'll somehow vent the inside without ruining sound quality, I'm thinking counter rotating 40mm fan at 5 volts, and a small exit/intake, naturally with a good fan filter to keep out the dust.. I'll have the coolest running Promedia amp in town, literally :santa:
 
well i guess i will never know if that info was right because i just shorted out another component :( I tried to put that heat spreader back on that i had removed, but i guess i missed the fact that the 3 clips holding it to the 3 chips were not touching, well i left them touching and got a nice spark show when i turned the unit on to check if i was having the same symptoms as the post. somehow i doubt Klipsch will repair it now even. luckly there is an ebay auction going on for just the amp so maybe i can snag that
 
You may want to find an electrician in your town to see if he will tell you what is wrong. Usually, they will tell you whats wrong for free, and repair for a fee.
 
You also may want to contact Okhlahoma Wolf, a senior member on these forums, he is a professional Pro-Audio tech nd has about 20 years of field experience. :)
 
Is your set an Ultra? If so check R527 in the power supply section.

I also have a dead amp, i've been scouring the web and seems like the mini regulator on mine is toast. BASH HC1011. Which you can buy from infinity/HK. I haven't fixed mine yet, because something caused that regulator to fail. Either from a bad sat. amp or just overheated.

The fact the sub is working means the section with the R527 resistor is still working. Most likely the regulator board on the board with black heat sinks has gone bad. The best way to troubleshoot the regulator is by swapping in a replacement board (not practical for a do-it-yourselfer). There is a small chance that one or more of the satellite amplifier boards has gone bad, drawing too much current and causing the regulator section to fail. See what the voltage to the satellite amps is (should be at least 7 volts for a non-Ultra). Current at idle (no signal) should be under 1/2 amp going to all 5 satellites combined. (Again, that will be hard to measure if the regulator board is dead). I'll guess your satellite voltage and current is now 0.

I get .5v coming out of the sat board. I get 10.5v coming out of the sub board. Out of the power supply, I get 56.5v into the sats and 84v into the subs.

I got help from a guy that repairs these things for money. This is as far as i've gotten. He would charge about 50+ shipping including an upgrade mod to cool the power supply. He Install fans on the power supply section.

This is as far as i've gotten. I just didnt want to spend the 20 bucks yet and figure that it'll be busted again. Still debating if i should just get it repaired for 50 bucks.

Hope this helps.
 
Trike007 thanks for the info. could you share with me the name of this member who repairs the amps, because i have given up personally because i really don't have enough knowledge of these things since it seems its a lot more than simply swapping out an obviously broken component like i thought
 
Just ship the amp back to Klipsch. i was all over their site last night looking to buy a 5.1 subwoofer...(egay has them for $300-$600). I ran across several threads in their forums where people have sent in their hosed sub/amps and Klipsch fixed them for $75
 
Klipsch 5.1 Promedia Ultra Replacement parts

I was wondering if anyone know where i can find replacement parts like a zov with the part # "TVR 14181 VDE 5U", and the fuse with the part # "t5a l250v" or recommend better parts I can use for the Klipsch 5.1 Promedia Ultra internel parts? Does any local places like radioshack or online places like ebay sell those similar parts or better parts?
 
Replaced R527

I replaced R527 with a 2 watt 47 ohm resistor and now my subwoofer and satellites work but the sometimes the signal has static. The problem is easy to hear at middle volumes like between 25 and 45 (on the klipsch controller) but I when I turn he volume up to 60 or 70 the static is much harder to hear. I read on the klipsch forums that someone was saying that there's a "special diode" which connects to R527 and can sometimes be problematic. However, he only said it was a "special diode." Could he meant like a zener diode or germanium diode or something like that?? Does anyone have any idea what he meant by special diode or if this relates to my problem at all?
 
bash amp repair!!!

i havent tried this yet but i hope this helps out a little. my promedia 5.1 sys. is also dead. amp works with sub only. seems that the MOSFET switches are dead. heres what to do....
this solution is for those of you with the problem of the Satellite speakers dying or cutting off and on, but the SUB is ok. This solution probably also fixes those systems which have the opposite problem: The SUB cutting out or dead, but the Satellites are ok.

Both SATS & SUB use identical components (chips) for power switching, but are on opposite sides of the same board.



OK, here what you’ll need to do

You’ll need to know basic soldering, so you’ll need a soldering iron with a fine (small) tip, solder, and soldering flux. Also get a solder sucker to remove the old solder. Don’t use the copper braid stuff to remove it; it takes too long to heat up and that extra time can heat damage your board’s components.



PARTS NEEDED:

Quantity 2: high speed MOSFET switches, part number IRFZ44N. Part number IRFZ44 can be used as well. Equivalents from other suppliers will work too.

These part numbers are equivalent to the NTE part number NTE2395. Go to www.NTEINC.com and use the cross reference. There you can read the spec sheet if you’re into that sort of thing. There, also in the specs, you can see a drawing of the part if you need a visual clarification. Click on the parts distributors in your state link to find parts suppliers nearby. I found a store nearby who had the IRFZ44 chips. There’s also online distributors, but beware online of the minimum order; that will cut into your savings!

This NTE site is a favorite for “OLD SCHOOL” component level electronics troubleshooters like me! I’m not really “old” though, I can still dunk a basketball! (occasionally).





!!!!!!!!!!!!!!!!!!!Remember to unplug your power cord 1st!!!!!!!!!!!!!



The board you’ll be replacing parts on is the one containing the BASH circuitry. From here on I’ll refer to it as the crossover board. You can identify it by looking for the two little boards on it with the word “BASH” on the outside of each one. This board is the “switching” part of this switching power supply. This also is the signal crossover board; it separates the high and low frequencies. Notice the 2 big copper coil wound inductors, just like the crossovers found in car and home speaker boxes. This board also ties the low level preamp signals from your PC, to the high level amplifier circuitry of the Klipsch system. You can find this board by following the Red & Black wires that daisy chain across the top of the surround (SAT) boards back to where they start. Again it’s the board with the 2 smaller boards with the words “BASH” on their sides. To remove the crossover board, unscrew the 2 screws on the outside cover. You will also have to remove the 2 sets of Red & Black wires from each side of the crossover board. Label the wires accordingly. The words, SUB (+) & SUB (-) are on the board next to one heatsink, SAT (+) & SAT (-) are next the other. I will be referring to these wires again in the next section.



The crossover board has 2 identical circuits, one side is for the SATELLITE speakers, and the other side is for the SUBWOOFERS. You can figure out which side you need by looking at the Red & Black wires mentioned above. The daisy chained Red & Black wires from the 5 SATELLITE amplifier boards plug into the SAT+/-. The other Red & Black wires with SUB+/- go to the SUB amplifier board. Remember, the SUB board is the only board not connected in the daisy chain. If needed, cut the cable ties holding these wires to make sure you trace them correctly. These wires plug into both sides of the crossover board. Remember to look for SAT+/- & SUB+/- written on the crossover board itself. There are 2 black heatsinks (plates) on each side of the crossover board near each Red & Black wire plug-in. The heatsink near the SAT plug-in is for SATS and the one nearest the SUB plug-in is for the SUBS. On each heatsink there are 3 black clips. These clips have holes on one side of them. These clips hold 3 chips on to the heat sink. Remove the clips. I used a small flathead screwdriver by lifting (spreading) the clip and sliding it off. Under each clip are the following:



Quantity 2: MOSFET switches (a kind of high speed switching transistor). The number on these 2 chips is IRFZ44N.



Quantity 1: Semiconductor Diode. The Part Number on this one is U1520. (You will NOT be removing this chip). It’s hard to find it aftermarket (not impossible) so BEWARE!!



Hint: The MOSFETS have 3 legs; The Diode has 2 legs!!!!



Remove the heat sink by unscrewing it from the board (2 screws). The 3 chips will stay in place. Take care not to damage the cards with “BASH” written on them or you’ll probably regret it!

Remove the plastic liners from the back of the 2 MOSFET chips. You’ll need these for the replacement chips so do not throw them away, put them aside. You’ll notice there’s a white paste on them, this stuff is heat sink compound, available at any Radio Shack. I just re-spread & re-used the compound already on the liners and chips.



Removing the 2 MOSFETS, Part Number IRFZ44N:

I found it easier to just bend them back and forth until the legs snapped off. That way they are out of the way to get to at the solder joints. You’re going to heat the solder joints up. Put flux on the joints before you heat them. With flux, they will heat a lot faster causing less damage to the board. Suck the points clean of solder & remove the broken off legs using the solder sucker and a small needle nose pliers or tweezers.











Installing the new MOSFET chips:

Push them through the solder holes making sure the backs of the chips (silver side) are towards the “BASH” cards, identical to the U1520 diode chip. If you put them in backwards you’ll probably regret it!!!

Make sure the height of the chip is about the same as the U1520 diode chip. It doesn’t have to be perfect, but be in the ballpark. I did this by bending the legs on the solder side (back side) of the board when the height was correct.

Solder the new chips on to the board. Solder on the back side only. Remember to dab flux on the legs and solder points first, this makes the solder flow fast and heats up the replacement chips less. Add new solder to the tip of the soldering iron only, not directly to the legs. This reduces the heat on the new chips. Touch the soldered tip of the iron to each leg of the chip. With flux on the legs, the solder will quickly flow into the solder joint. Add more solder to the iron as needed.

Remember to cut the extra bit of leg off after each soldered joint when you’re done. You don’t want the legs to bend & touch or you’ll probably regret it.



Viola! You got yourself a repaired crossover/switching board, (you repaired the switching part) and you saved some time & dough $$!!

Re-install the heatsink and liners. Reconnect the plugs and remount the board.
 
I have a whistling Klipsch 5.1 amp anyone can help?

This started recently but it's very anoying. On powerup there is a low pitched noise that over time turns into a high pitched whine. Appears to be coming from the sub. Anyone seen/heard this before? How to fix? Thanks.
 
More info

To get by in the meantime I have bought the Logitech Z-5500 and these are working well but don't have the "crispness" of the Klipsch Ultras. I have taken the Klipsh sub apart and disconnected the 8" speakers. Connected the controller and power. On powerup I hear a hissing sound coming from the cross-over board (?) its the board with the two tall copper coils. Next order of business it to replace the FETs referred to in an earlier post and see if the noise goes away? I have a scope, what should I look for as far as signals go?
 
So much for help. I was poking around with a scope probe today and appear to have tracked down the source of the noise. It appears to be coming in from the amplifier board T-500WRB on the power lines for the sub. This board has two power outputs one for the sattelites and one for the sub? I found the 2.3Khz noise on J503 which was feeding power to the board with the two big copper coils.

By far the hottest part on the amplifier board is a single resistor that is on a small 1x1.5" pcb that is connected to the main PWB. I think it is R7 and the ohm meter reads it to be a 100k resistor. The markings on it are nearly burnt up. Anyone have any insight? I am thinking of unsoldering the small PCB and replacing as many components on it as I can.
 
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