Convert a class ab amp to class a amp

[rahul_muzik]

Hello diy'ers and knowledged guys

I'm in interest of changing a class ab amp to class a amp of push pull design. I have read through common article on Google search. What I found is they have similar design except the resistance placed in such a way which make a class a a class ab. I understand that fiddling with company design may spoil all of it. So I just want to take a calculated risk . Another problem is basically the heat sink design, class a have much higher heat sink in design which makes me think to change the chasis.

Regards

 

[rahul_muzik]

So many views & no reply. Still waiting for directions

 

[greenhorn]

Given that neither you nor I are masters of amplifier design, I think it would be easier to bypass the power amp stage and swap in some other class A boards on the existing heatsink/enclosure. Add a fan if the power dissipation requirements are higher :/

on the other hand, people who can design this here probably think it's not worth it

 

[greenhorn]

After a bit of reading, i think it can be done if you know your basics of electronics theory and biasing. At least it seemed achievable to me. But the complications are
1. If the amp has done negative feedback, especially global negative feedback, things might get a bit more complicated as designing with feedback is vastly more complicated than simple biasing as one is just basic transistor design, and the other is network design with bode plots etc at which i know I suck
2. Negative feedback and the push pull configuration mean that you lose a lot of even order harmonics which are not that bad compared to a single ended class a. Which is also why most popular class a designs are single ended