Have you ever opened up a simple electronic equipment like a guitar amp but found it to be very complicated on the inside? Even if you have the experience with technology like it this it can be difficult to figure out some products.
For cases such as these what you need are schematics, these will give you a clear picture of how the product’s circuit works so you can make the proper repairs.
In case you decide to not do the repairs then you might want to look at new products such as the best acoustic guitar amps.