As others before me, I suggest to just connect a speaker (or an 8 Ohm resistor) across the outputs and measuring the transient behaviour again ...
Output capacitor is already almost the best speaker protection
Best regards, Claas
Output capacitor is already almost the best speaker protection
Best regards, Claas
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've done it using a unity gain op amp inverter to drive one channel so I could run the amp as a bridged mono block. It works very well. I did with two amps and it worked great.
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.
You could also run the channels in parallel, use a Y-cord to the input, and parallel the output jacks. I had one wired that way just a couple of days ago and totally forgot to get any photos…. Whoops.
Anyway, it worked great.
Anyway, it worked great.
6L6
Anyway you could do a picture of that
Or maybe a quick sketch up drawing on that bridged hookup?
Thanks
Anyway you could do a picture of that
Or maybe a quick sketch up drawing on that bridged hookup?
Thanks
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
Thanks Zen
That sounds simple enough.
Running this mini in bridged mode will it possibly run those small
Heatsinks to hot for those fets to handle?
That sounds simple enough.
Running this mini in bridged mode will it possibly run those small
Heatsinks to hot for those fets to handle?
6L6
So speaker connections would be the 2 positive terminals if running in parallel
and no ground right?
So speaker connections would be the 2 positive terminals if running in parallel
and no ground right?
Please excuse the very crude y-cord on the input.
