I'm guessing that you have a solid state amp. I would contact the manufacturer and request the instructions on how to set the DC offset and bias. More than likely the only tools required will be a meter and small tweaker screwdriver. I have a Classe CA400 that at idle was warmer on one side than the other. I do not recall the temp range but it was noticeable to the touch. The DC offset and bias was way off for both channels. After adjustments the amp sounded substantially better. I can only guess why the settings were off. Thermal expansion and contraction, vibration or maybe some fine tuning by ear?
For people with experience with Class-A amps
Hi All,
I had a question for all you audio folks who have experience with Class-A power amps as I am new to this myself.
This is bugging me so I finally decided to ask - I have a class-A power amp (name will be with-held to protect the innocent) where I notice with no shade of doubt that the right heat-sink is warmer to the touch than the left heat-sink after about 2 hours of play/program material.
I got hold of a thermometer & measured the heat sink temperature (stuck the thermometer probe deep into the heat-sink fins & waited for the temperature read-out to increase/decrease by 0.1 degree Celcius).
What I found was that the right heat-sink was 1.5 - 2 degrees Celcius HIGHER than the left heat-sink. I have about 4 readings so far. Altho' not a lot of data points, each measurement has the identical trend - right heat-sink was 1.5 - 2 degrees Celcius HIGHER than the left heat-sink.
This indicates to me that the right channel current bias is more than the left channel current bias. Am I correct in my thinking?
2ndly, should I be worried about this?
(in that, over time, this temperature differential could diverge & the amp could run away thermally?).
Should I get the dealer to adjust the bias so that both channels are more or less equal?
I realize that "more or less equal" is a fuzzy term. To that effect, in your respective experiences, what should the temperature differential be between the 2 channels? 0.5 degree Celcius? Less? More OK? if more, upto what point OK?
Thanks very much in advance for your help.
I had a question for all you audio folks who have experience with Class-A power amps as I am new to this myself.
This is bugging me so I finally decided to ask - I have a class-A power amp (name will be with-held to protect the innocent) where I notice with no shade of doubt that the right heat-sink is warmer to the touch than the left heat-sink after about 2 hours of play/program material.
I got hold of a thermometer & measured the heat sink temperature (stuck the thermometer probe deep into the heat-sink fins & waited for the temperature read-out to increase/decrease by 0.1 degree Celcius).
What I found was that the right heat-sink was 1.5 - 2 degrees Celcius HIGHER than the left heat-sink. I have about 4 readings so far. Altho' not a lot of data points, each measurement has the identical trend - right heat-sink was 1.5 - 2 degrees Celcius HIGHER than the left heat-sink.
This indicates to me that the right channel current bias is more than the left channel current bias. Am I correct in my thinking?
2ndly, should I be worried about this?
(in that, over time, this temperature differential could diverge & the amp could run away thermally?).
Should I get the dealer to adjust the bias so that both channels are more or less equal?
I realize that "more or less equal" is a fuzzy term. To that effect, in your respective experiences, what should the temperature differential be between the 2 channels? 0.5 degree Celcius? Less? More OK? if more, upto what point OK?
Thanks very much in advance for your help.