How do I make a high power audio amplifier?

How To Build An Amplifier?

• Alright, so I have been off the forums (diyma, 12volt, etc) for quite some time now. I am very knowledgeable W/ "mobile audio" & I am a total noob W/ certain things. I can tell you all about characteristics of various cone materials, tweeter composition, slopes, crossover points, & even a bit of pyscho acoustics (diffraction & reflection). However, I still do not know how to build an amplifier! I have a very basic understanding of FETS, transistors, Caps, Resistors, etc. However, I am up for the challenge. I understand there are several types of amplifiers. This will not be a "tube" amplifier. It will be a "mobile audio" amplifier. Now I know those of you who are knowledgeable W/ audio are going to be laughing at me cuz people do make tube amplifiers that run off DC power. -Take a look at McIntosh. Anyways, so the amplifier I will be fabricating will be ran off of DC Power. Now there are several types of amplifiers right? Class D, A, A/b, G-H, etc. So what type? Well, this amplifier will run a set of Mids for now (I will explain crossover below) so I take it I will be using A/B (for whatever reason?). Class D seems more geared towards "subwoofers." Class G-H is beyond me. I believe ARC & Vibe uses this "new" idea or whatever you want to call it & class A amplifiers are not efficient at all. Watts. I take it this will be my next quesiton? My speakers rate 25 watts. yes, RMS so I figure 30-40 watts RMS should be a good target/goal. They run at 8 ohms, yes they are "raw drivers." -Now this is beyond me & I am not sure how this plays a role. Okay, so here is a few other things I know: Most amplifiers, if not all are built off PCB boards, correct? I know there's a lot of youtube tutorials on how to etch your own & I'd be up for it. I have a few starter breadboards that I could play around with. Cooling: LOL, I assume I will be running fans. Now how does this work? I took a look at a few of my amplifiers and it appears as the FETS run off the heatsink. Are the FETS the only things that gets hot? Oh, my active crossovers will be done at the Source so all I need out of this amplifier is raw power. An amplifier is just a voltage booster right? Gain: Okay, I understand the gain is there to match the signal output from the source to the amplifier right. So what if I know the exact voltage coming from my source, than can do I even need a "variable" gain adjuster? Ha, so I know a bit here & there, but if someone could sum it up for me that'd be great!

• Answer:

  Apply input signal in Gate of FETS and Collect output from Source- Drain Terminal Ckt