09-20-2018, 10:25 PM
(This post was last modified: 09-21-2018, 04:38 PM by soundmasterg.
Edit Reason: fixed typos
)
Hi Kevin,
I have a scope and a signal generator, and a true RMS DMM, and a suitable bench load. What I have done is to put the signal generator signal into my amp once I have verified the AC voltage level from the generator. If I remember correctly I had it set at 120mV to simulate a typical humbucker guitar and I used 1kHz instead of the 400 Hz that you suggested. I have the amp output plugged into an 8 ohm resistive load, which is probably 100-200 watts. These are huge resistors. Then I bring the volume of the amp up and play with the controls until I get the max signal before clipping, watching the sine wave on the scope. I back it off just below the clipping threshold and measure the output with my DMM as an AC voltage. I then square that voltage reading on the DMM and divide it by the resistance to see what the power output level is.
Is this an accurate way to find out what the RMS power output of the amp is?
Greg
I have a scope and a signal generator, and a true RMS DMM, and a suitable bench load. What I have done is to put the signal generator signal into my amp once I have verified the AC voltage level from the generator. If I remember correctly I had it set at 120mV to simulate a typical humbucker guitar and I used 1kHz instead of the 400 Hz that you suggested. I have the amp output plugged into an 8 ohm resistive load, which is probably 100-200 watts. These are huge resistors. Then I bring the volume of the amp up and play with the controls until I get the max signal before clipping, watching the sine wave on the scope. I back it off just below the clipping threshold and measure the output with my DMM as an AC voltage. I then square that voltage reading on the DMM and divide it by the resistance to see what the power output level is.
Is this an accurate way to find out what the RMS power output of the amp is?
Greg


