I replaced the blue light, I had a bad one out of the box. The new one works fine, but I got it at Microcenter. Is it possible that this can cause a short?
It was working fine yesterday, and now nothing.
I am sorry, but I am a total noob when it comes to resistance check. Break it down in easy to follow steps
Yes I thought that too, but when I set up in stereo left channel plays fine
Just right not working
I am stumped. I tested the bias and it still reads the same on the left board as I set it too. I swapped poles and nothing.
I can leave the switch up and run one pole to left and far right pole and it works fine
I can leave the switch up and run one pole to left and far right pole and it works fine
Hi ryan391,
You need to make sure the fault is not a shorted Black speaker socket or shorted input (RCA socket) before moving on. Either will stop the ACA working. The fact it was working hopefully means something has moved since then.
With the Rear switch in the central position:-
Put your meter on resistance (range 2kΩ) and put one probe into the Red speaker socket and the the other probe into the Black speaker socket, You should read between 500Ω and 1000Ω (1KΩ). If you read zero ohms there is a short on the black socket. Usually the metal post of the socket is touching the chassis as the washers are not installed correctly.
Now set the resistance range to 200kΩ and put one probe on the outer gold ring of the RCA socket and the other probe on the central RCA connector, where the red wires are soldered to. You should measure about 50kΩ. If it is zero then there is a short. Usually a blob of solder or strand of wire.
Let us know how these measure so we can fix or eliminate them.
You need to make sure the fault is not a shorted Black speaker socket or shorted input (RCA socket) before moving on. Either will stop the ACA working. The fact it was working hopefully means something has moved since then.
With the Rear switch in the central position:-
Put your meter on resistance (range 2kΩ) and put one probe into the Red speaker socket and the the other probe into the Black speaker socket, You should read between 500Ω and 1000Ω (1KΩ). If you read zero ohms there is a short on the black socket. Usually the metal post of the socket is touching the chassis as the washers are not installed correctly.
Now set the resistance range to 200kΩ and put one probe on the outer gold ring of the RCA socket and the other probe on the central RCA connector, where the red wires are soldered to. You should measure about 50kΩ. If it is zero then there is a short. Usually a blob of solder or strand of wire.
Let us know how these measure so we can fix or eliminate them.
I have no idea. The output is like 900 on both sides.
The RCA do not register on the gold part, but do on the internal wires. used a desolder wick and removed all the solder. redid the wire and still nothing.
left side behaves the same, but works.
The RCA do not register on the gold part, but do on the internal wires. used a desolder wick and removed all the solder. redid the wire and still nothing.
left side behaves the same, but works.
Sorry to ask again, but what resistance do you measure on the input wires? We are trying to eliminate things...
I assume you have swapped the speakers and inputs (from your source) from left to right? That will eliminate the source and your speakers.
I assume you have swapped the speakers and inputs (from your source) from left to right? That will eliminate the source and your speakers.
Yes, I have swapped left and right. works fine in stereo left, but nothing right.
If switch is up and connect left black and right red, works too. bias on the boards are stable and equal too.
Also tried a balanced input cable. in Center stereo mode switch up works as mono, switch up, does not
If switch is up and connect left black and right red, works too. bias on the boards are stable and equal too.
Also tried a balanced input cable. in Center stereo mode switch up works as mono, switch up, does not
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I completely rebuilt the amp that was faulty. I have two working ACA's. Now the newest possible problem maybe nothing. But one is louder than the other. I have them all biased at 12.3. I am using my pre amp to center the stage. Before anyone asks. I have swapped every conceivable thing. I even swapped the pre amp just to make sure. Any ideas?
The gain is determined by the values of R11 and R12 but is complicated by R10.
So make sure all those resistor values are correct and are the same between channels and also the two amplifiers.
So make sure all those resistor values are correct and are the same between channels and also the two amplifiers.
so in an ideal situation R11, R12 and R10 would be perfectly matched on all channels and both amps? Otherwise, nothing is wrong just not matched?
They would have to be miles out before you noticed any problems but it can happen if you fitted say a 100k instead of a 10k or a 3.9k instead of a 39k You would notice that for sure.
Small differences such as tolerances (even if you used 10% or even 20% tolerance resistors) would not not be immediately obvious such is our perception of volume and loudness.
Small differences such as tolerances (even if you used 10% or even 20% tolerance resistors) would not not be immediately obvious such is our perception of volume and loudness.
I took apart the newer, quieter amp. I pulled R11, R12, and R10 out checked and reinstalled. No change.
I think maybe one is just a little more powerful than the other? could this be?
They sound great, although I have to adjust balance to the left by 5 clicks to have. better center stage.
I think maybe one is just a little more powerful than the other? could this be?
They sound great, although I have to adjust balance to the left by 5 clicks to have. better center stage.