What's involved in diagnosing and repairing amplifiers?

[mrbojang 8]

I'm thinking of purchasing a cheap broken amplifier off ebay just to try to learn to repair it. I'm a fairly fast learner and am good at learning new things, so it seems like it might be a fun challenge...

What's exactly involved? I know I would need a test power supply (computer psu?), dmm, soldering kit...

Is the basic technique to just look for components that are burnt or have failed and replace them?

[shizzzon 461]

A DB-r is involved too. Without that, it's very hard

[Impious 1,476]

It's a little more involved than that. Having an understanding of the electrical engineering involved....what the parts are and why they are there.....is going to be useful and necessary. Understanding why something was damaged is vitally important. The damaged part that's easy to see might have been damaged as a result of something less obvious to see. Ofcourse there are always simple fixes like an old cap that simply went bad. But things aren't necessarily going to be that easy and in some cases some diagnostic work will be required. If you don't understand anything about the operation of an amplifier, then you aren't going to be able to do this.

If you want to learn how to repair amplifiers, I would start with learning how amplifiers are designed. If you have to ask what's necessary equipment to repair an amplifier, then you aren't ready to start repairing amplifiers.

[mrbojang 8]

It's a little more involved than that. Having an understanding of the electrical engineering involved....what the parts are and why they are there.....is going to be useful and necessary. Understanding why something was damaged is vitally important. The damaged part that's easy to see might have been damaged as a result of something less obvious to see. Ofcourse there are always simple fixes like an old cap that simply went bad. But things aren't necessarily going to be that easy and in some cases some diagnostic work will be required. If you don't understand anything about the operation of an amplifier, then you aren't going to be able to do this.

If you want to learn how to repair amplifiers, I would start with learning how amplifiers are designed. If you have to ask what's necessary equipment to repair an amplifier, then you aren't ready to start repairing amplifiers.

You're right, I can't just jump in and expect results. Building small scale amplifiers (headphone amps, etc) and learning the theory of them is probably the route to go. Thanks.

[aimone 4]

i myself have thought of ordering this...i to wanna learn theres money to be made in it and get amps cheap and fix for peersonal use

Learn To Repair Car Audio Power Amplifiers

[GlassWolf 5]

i myself have thought of ordering this...i to wanna learn theres money to be made in it and get amps cheap and fix for peersonal use

Learn To Repair Car Audio Power Amplifiers

Perry is a great guy. I own both his repair CDs, and his website on CD. Well worth the cost, if for no other reason than to support his work.

You will need tools for this type of work though, and I can tell you first hand, that the tools are not cheap.

A few tools off the top of my head that you'll need are:

True RMS digital multimeter

signal generator

high current regulated DC power supply

oscilloscope with various probes

the actual schematics for any amplifier you plan to repair, most likely

a high-current resistive dummy load

variable wattage soldering station (weller is good)

Edited May 28, 2010 by GlassWolf

[ssh 924]

i myself have thought of ordering this...i to wanna learn theres money to be made in it and get amps cheap and fix for peersonal use

Learn To Repair Car Audio Power Amplifiers

Good luck

[footlongsam 0]

I've been in the school of electronics for 1 year now, and I will say that it's not something you'll lern over night, I did just pass a test over Metal Oxide Feild Effect Transistors (MOSFTEs), and just in understanding how they work takes a lot of time.. 2 weeks for me studying every other night. There's more than one way they work, and 3 of the ways are effected by Beta DC and output will vary with tempurature change

[brightmix 0]

Good one, Stewart. And I think I need to get off that road now...ha, ha, ha...