do you hear any crackle or pop sounds from your test loudspeaker?
Nope.
Measured again with a load (6 Ohm speaker) and it's very different. At startup (bias switch turned on), voltage spikes to ~60mv and drops down to 30mv within a few seconds (and continues going lower until settling ~4mv within 20secs). Same thing when bias is shut off. MUCH better than without load.
Shorting the inputs makes no difference (with or without load).
Some might find this useful.
Here is the voltage across the load (a 1k and then 6 ohm) at power on. The supply rises to 24 volts at 2 seconds in. The second image is with the 6 ohm load in circuit.
The final image is the 6 ohm with the voltage scale expanded. Simulations aren't the be all and end all but the result should be in the right ballpark I would think. The time constants are what they are... long
Here is the voltage across the load (a 1k and then 6 ohm) at power on. The supply rises to 24 volts at 2 seconds in. The second image is with the 6 ohm load in circuit.
The final image is the 6 ohm with the voltage scale expanded. Simulations aren't the be all and end all but the result should be in the right ballpark I would think. The time constants are what they are... long
I'm not sure how much you know so here's the whole thing. Run your audio source to the inverter and its output to the input of one channel of the amp. Run the same source directly to the the input of the other channel of the amp. Then one channel gets a normal signal and the other gets the inverted version of that signal. You are now driving the amp in bridged mode.
The speaker output is taken from the two positive speaker outputs. Speaker + of the inverted channel is your speaker - and speaker + of the non inverted channel is your speaker +.
Of course this assumes you have an inverter. I built a board that does this for me.
But, the H2 Buffer in the DIYAudio store is actually a unity gain inverter. Perhaps that could work for you.
The speaker output is taken from the two positive speaker outputs. Speaker + of the inverted channel is your speaker - and speaker + of the non inverted channel is your speaker +.
Of course this assumes you have an inverter. I built a board that does this for me.
But, the H2 Buffer in the DIYAudio store is actually a unity gain inverter. Perhaps that could work for you.
input grounds are already parallel
output grounds are already parallel
connect in parallel input hots
connect in parallel output hots
use one channel for input, use one speaker for output
read F4 manual for some funny thoughts
firstwatt.com then products, then F4
output grounds are already parallel
connect in parallel input hots
connect in parallel output hots
use one channel for input, use one speaker for output
read F4 manual for some funny thoughts
firstwatt.com then products, then F4
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