I do have +16.2v and -16.2v on the legs on the RH side of the amp(The end with the rca imputs pict.1&2) and +16.0v and -16.0v on the LH side of the amp(the end with the speaker outputs pict. 3&4).
Pic#1 Pos 16.2
Pic#2 Neg 16.2
Pic#3 Neg 16.0
Pic#4 Pos 16.0
In Pic#5&6 Is the center section that has no readings on leg 3.(this may be normal)
Should I take the pics showing the meter? please let me know if that will make thing easier.
Pic#1 Pos 16.2
Pic#2 Neg 16.2
Pic#3 Neg 16.0
Pic#4 Pos 16.0
In Pic#5&6 Is the center section that has no readings on leg 3.(this may be normal)
Should I take the pics showing the meter? please let me know if that will make thing easier.
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Sorry for taking so long. I had to use my car for a bench test, the Right channel has no output. left channel seems to be working. While in the car I double checked the wiring plug for the amp and all connections are tight and I also checked Input RCA's from the crossover and both L&R channels from the crossover work individually through the left channel input RCA on the amp to give a signal to the sub but nothing comes out of the right channel input of the amp. I tried the amps L&R output on each sub individually. Both of the subs work individually. So It must be in the amp somewhere. The channel that has no output is the +yellow wire and the - black w/yellow trace (Left channel?). Now I'm really confused! So it seems that the right channel input RCA on the amp plays nothing through the right channel output?(no signal) But the Left channel input RCA on the amp plays through the Right channel speaker output wires.
That is unless I’m wrong about the coloring on the speaker output wires (Yellow and black w/yellow trace is the Left channel correct?)
That is unless I’m wrong about the coloring on the speaker output wires (Yellow and black w/yellow trace is the Left channel correct?)
You are correct. The right RCA drives the yellow and yellow and black wires.
Take the wires from one woofer and connect the negative terminal to the small black wire coming out of the amp. Touch the other speaker wire to all 4 speaker wires coming out of the amp. Which ones produce clean audio. Which do not.
Take the wires from one woofer and connect the negative terminal to the small black wire coming out of the amp. Touch the other speaker wire to all 4 speaker wires coming out of the amp. Which ones produce clean audio. Which do not.
Just to confirm. Take the small ground wire (the one thats supposed to ground to the deck) and run it to the ground terminal of one of the subs, then test the right and left channels speaker wires to that sub (wiree normaly) and see which channel sounds the cleanest?_
Or do I just use that ground wire as the negative speaker wire, and try the four wires R+,R-,L+,L- to the positive speaker terminal to see which is the cleanest?
Or do I just use that ground wire as the negative speaker wire, and try the four wires R+,R-,L+,L- to the positive speaker terminal to see which is the cleanest?
Ok, Just tested using the sm. ground wire as the negative speaker wire and one by one tested each wire.
Yellow wire= no sound
Black with yellow trace= no sound
Orange wire= sounds nice
Black with orange trace= sounded little sloppy. Not as deep or as loud for the set volume as the orange wire
hope this makes sence to you, I'm lost.
pic#1 working left RCA
pic#2 left RCA to board
pic#3 Orange and black and orange wires out to speaker
Yellow wire= no sound
Black with yellow trace= no sound
Orange wire= sounds nice
Black with orange trace= sounded little sloppy. Not as deep or as loud for the set volume as the orange wire
hope this makes sence to you, I'm lost.
pic#1 working left RCA
pic#2 left RCA to board
pic#3 Orange and black and orange wires out to speaker
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This is actually a 4 channel amp that has two channels bridged for each output channel. The tests seem to indicate that you have 3 defective channels.
I'm assuming that the dead channels are always completely dead and nothing (moving the RCAs in the jack or rotating the gain control) make the amp produce any audio from that channel. Is that true?
Do you have a test tone CD or a sine wave generator?
I'm assuming that the dead channels are always completely dead and nothing (moving the RCAs in the jack or rotating the gain control) make the amp produce any audio from that channel. Is that true?
Do you have a test tone CD or a sine wave generator?
Yes, that is true I do not have anything at all out of the Yellow & Black w/yellow wires, the Black w/orange wire sounds out of phase, and the orange wire sounds good. You are correct, rotating the RCA's,Gain controls,wires, plug ect... has no effect. Sorry, I do not have a test CD or a sign wave generated.
I don't know if it has any relevance to the issue and my timeline may be off a bit. My amp has been disconnected for about six months. When I disconnected the amp the sub that was connected to the yellow/blackyellow speaker wire did have some issues around the time that channel quit. During the previous few months (before it quit), I could hear one of the subs dropping in and out going down the road. I would just turn it down for a while and it would start working again. At the time I figured that one half of the amp was overheating and shutting down till it cooled a bit then it would start working again. Well one day the sub quit and never turned on again. That’s when I checked the wires inside the box and saw that the lead from the voice coil to the terminal appeared to have been hanging by a thread for a while and finally broke. Anyway, I soldered it back on and the sub works. That is when I realized that the channel that was running to it no longer worked so I disconnected the amp(but did not remove it) and hooked up a little Orion 225 HCCA for a temporary replacement. Now I don't know if the broken speaker lead was part of the reason the amp is not working or if it was coincidence that they both happened at once???
That's normal.
Download this file, burn it to a CD (or whatever you can use to drive a signal into the amp).
http://www.bcae1.com/temp/100hz300seconds.zip
Drive a 1v signal into the amp (measure the AC voltage at the RCA jacks) and then measure the AC voltage on pine 1 and 7 of the op-amps on the preamp board. Post the voltage for those pins on both op-amps.
Download this file, burn it to a CD (or whatever you can use to drive a signal into the amp).
http://www.bcae1.com/temp/100hz300seconds.zip
Drive a 1v signal into the amp (measure the AC voltage at the RCA jacks) and then measure the AC voltage on pine 1 and 7 of the op-amps on the preamp board. Post the voltage for those pins on both op-amps.
I did run the CD but I have no way of generating a 1v siginal. I tried puting the meter on the RCA's and adjusting the volume to get 1v. My piece of S meter does not read anything coming out of the RCA's yet if you plug them in there is sound! I did run the volume around 1/4 of the way up and checked pins 1 & 7 on both op-amps. The one closest to the end of the amp reads (pin 1=8.7 and pin 7=8.8) on the one farthest from the end of the amp reads (pin 1=11.4 and pin 7=10.6)Please note that the only way to get any reading on the meter I had to set it to (200m see pic) so I'm not sure what that would be in VDC. I do not no if this is of any help since I do not have the proper testing equipment. Also I just realized I used the left and right RCA channels plugged in to the amp which may have a slightly differnt output voltage from left to right due to the line level imputs. Should I try to re-do the test using the same RCA imput on both channels to get a more accurate reading from left to right?
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I just checked it again and I still get nothing when testing the RCA's. I even used some old meter I found in the garage(Old). Still if I plug either one into the left RCA imput I get sound.
This time I tested both op-amps with the same RCA cable. Volume set to 1/4th. With the RCA going into either input. The op-amp closest to the end appears to have less power than the one furthest from the end(not by much, but less). Below are several pics of the test but the meter is all over the place so it may not be much use(I never got the same reading twice in a row with the Harbor Freight special). I don't know if I can get my hands on a better meter but I'll see if I can borrow one. Sorry Pics got mixed up, so they may be a bit random. Thanks
This time I tested both op-amps with the same RCA cable. Volume set to 1/4th. With the RCA going into either input. The op-amp closest to the end appears to have less power than the one furthest from the end(not by much, but less). Below are several pics of the test but the meter is all over the place so it may not be much use(I never got the same reading twice in a row with the Harbor Freight special). I don't know if I can get my hands on a better meter but I'll see if I can borrow one. Sorry Pics got mixed up, so they may be a bit random. Thanks
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