Newbie Question

[rjon17469]

Hi everyone,

For those of you annoyed by newbie questions, I'll steer you away now.

I am a speaker builder thus far. Recently however I have been looking into amplifiers, and have been wanted to create my own.

Looking over some designs and through some posts, I have a question: what is the specific use of capacitors in amplifier designs?

I understand how caps work and how and why they work in low-pass crossover circuits, but I don't understand how they can provide 'speaker protection' or how they can be useful in a power supply.

And my other question is, if transistors are the basis for a solid-state amp, then what is the rest of the stuff for (i.e. all the extra resistors, caps, etc.)?

Thanks in advance!

Reece

[jaycee]

In a power supply, capacitors serve two primary functions - as filtering, and as energy resivoirs. The filtering is so that all the **** from turning AC into DC is filtered out and the voltage smoothed to more or less a constant level. As energy resivoirs, they supply huge amounts of current required to reproduce bass transients (which is why amplifiers with plenty of bass have large capacitors )

In a speaker protection circuit, they are normally used to form a low pass filter. Then a detector is set up to trip when a large amount of constant DC is detected, if it wasnt for the filter, your amp would cut out on low frequencies.

In an amplifier circuit they are typically used in 3 areas - DC blocking, bootstrapping, and "Miller compensation".

[PMA]

Originally posted by rjon17469
Hi everyone,


Looking over some designs and through some posts, I have a question: what is the specific use of capacitors in amplifier designs?

I also was not sure what they were for when I was about 12 years old. So I started to omitt them. Sometimes it worked, many times it did not work at all.