klipsch promedia ultra 5.1 BASH amp

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i had the amp out and checked if the relay was working, and it is.
then i looked around for anything burnt and couldnt find anything.

so i was a little fed up and had the speakers connected to the computer, i was using trueRTA to send 30hz to the amplifier because the satellites work - just the subwoofer isnt working.

i turned the volume all the way up and nothing.. so i :nownow: and turned the subwoofer level all the way up with the main volume all the way up.
then i could hear some 'ticking' noise.
so i changed the frequency in trueRTA and listened to see if the 'ticking' also changed frequency, and it did.

so my question is.. what has died and am i foolish to believe that the 'ticking' i heard is a good indication to save the subwoofer?

i am not an electronics engineer.. i'm an infant hobbyist.
i have a klipsch promedia 2.1 sub and amp that has been working beautifully.
i changed the speakers to some 6.5 inch 2-ways that are 8 ohms and i havent had any problem other than the subwoofer box being tuned too high.

i would like to repair the ultra 5.1 amplifier rather than wait an eternity and people might possibly forget how to repair the amp.. or the details on the amplifier start to disappear, making a repair much more difficult.

i want to learn, and i also would like to use parts of higher quality than what klipsch would use if they repaired the amp.

is the situation above enough for someone to get a general idea of what is going on?

i seen this on the internet:
Klipsch Promedia V5.1 Amplifier Repair
but its all way too technical for me.
there are terms in the article that make my brain go cross-eyed with a lack of definition and comprehension.
 
55 views and not a single idea?

i dont know much of how an amplifier works, but i can tell you what bit i do know..
the voltage starts at the inputs and goes to a step-up transformer.
then that voltage is divided into two sections, one to push the cone forwards and the other to either halt the speaker cone or to pull the cone backwards.
then those two circuits come together at a transistor, and that transistor has a wire coming from the preamp inputs of the amp. that wire tells the transistor which circuit to let voltage pass (and that is how the transistor effects the output quality of the sound) .

so based on the above, i am hearing voltage from the preamp wire literally *zap* on the transistor ??!

that doesnt seem very likely unless the preamp signal has been heavily increased somewhere after leaving the soundcard.

all five of the satellite speakers work.. so that means the bash 'chip' is okay, unless there is a seperate one (or seperate circuit?) for the subwoofer.

i will have to pull the thing back out of the closet to find exactly where the audio is coming from.
i dont remember if it was coming from the crossover area or the far left of the amp rack (up top where all the 'amp' circuits are layed out in a row)
or maybe it was somewhere between those two spots.. i really dont remember.

if nobody is willing to help me with this.. i'll just have to let it collect dust.
 
Bash 1011

Yes there are 2 BASH 1011 boards on the plate amp.

I'm not sure what your exact problem is. I think that it is that your subwoofer is not working.

I had the same problem with my satelite speakers. The problem was on the BASH 1011 chip itself.

Check the heavy wires from the power supply to the board with the BASH chip on it. It's the top pair of black and red wires. It should have about 82 volts on it. If not the problem in in your power supply. If you have voltage here then it's proabbly the BASH chip for the sub amp.

What had happened is the solder joints were not strong enough to take the vibration and broke. So I would have intermintant sound from my speakers and it sounded horrable until it got warm enough to work.

The BASH 1011 chip your are after is the one above the crossover coils and black heatsinks on the left side. I suggest you use a low wattage soldering iron (less that 25 watts and prefferably 15 watts or lower) and once it's heated up fully touch both sides of all diodes for 2 seconds. No more than that or you can potentially dammage them or spread too much heat up the traces and dammage the transisters or chip hidden by the black resin.

Once you have done this, hook everything back up and test it. You can check for voltage at the top black and red heavy wires going up to the subwoofer amp. It should be somewhere between 15 to 20 volts.

The "zap" you are seeing is the amp requesting more power from a system that isn't "listening." This should be a step in the right direction.

Hope this helps and let me know how it's going!
 
i have a picture to show you what voltages i read and from what points.
the multimeter is a Gardner Bender GMT-12A

heres the picture with the details:
bashamp.png


my soldering iron is 30watt so i didnt try anything with 'heating up' some components. (i wasnt exactly certain which diodes you were talking about besides)
 
I circled the diodes on the bash image to heat up.

I also circled the pins on your picture that they are located at. The top where you are getting 0 volts is the one you want to try to heat up the diodes. I did mine with a 25 watt iron with ok results. Mine went to full on for my satelite spealers (52 volts).

Somthing that you can do to check to see if reheating the joints would help is to move the BASH board while you have a signal comming through it. If it kicks on for a moment then you know that the issue is a broken solder joing and reheating would be a good fix for you.

You can also replace the BASH board.
 

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