simple ne5532 and irf630

[lineup]

Sangram.
It is possible to use the method I describe in my TOPIC:
http://www.diyaudio.com/forums/solid-state/170795-op-amp-opa134-driven-power-amplifier.html

I show in first post the princip, simplified.
Then I show example that works well in SPICE.

 

[Sangram]

I was actually thinking of something with a few components added around the output stage - I've seen that other thread and the amp above is way beyond me for now. I already have opamps, power supply components and the FETs, as well as most of the resistor values in my junk box. I was hoping the answer was simple, but apparently not🙂

 

[LoveVirus]

Hello.
I use MultiSim, too.
I tested your circuit. It works well.

What I should change.
1. I should use +-18V Supply

2. Use NE5534P. Is a better opamp than NE5532
And you can build two channels separate. Dual Mono blocks.

3. IRF630 is better. 74 Watt. IRF610 only 36 Watt.
Myself, I should go for IRF540N/IRF9540N. More than 100 Watt


Here is my variant. No longer as simple as your. But it is not very difficult.

It gives max 14 Watt RMS into 8 Ohm
By using 2 BOOTSTRAP capacitors we help opamp to give higher volt out.
One thing to fix is the DC offset: -115 mV
This can be done using Pin1 and Pin5 of NE5534

I have a question,the ne5532 the output current is able to drive irf630 the gate?
ne5532 short current is 20ma
irf630+irf9630 Qg≈100nc
I=Q*f=100nc*100k=1e-2(a)=10ma
In this case the drive current is still a little nervous
I do not know such a calculation is correct?

 

[AndrewT]

Do the output devices need to be complementary?
Would an all irf540 quasi stage biased into ClassA work just as well?

Would biasing the 5534 (or any ClassAB opamp) into classA help?

How would a ClassA bias opamp compare to a 5534 using PIN5 as output?

Sorry lot's of questions and no answers.