Use of a Pre-Amp to Boost Amplifier Output

Use of a Pre-Amp to Boost Amplifier Output 

I have a couple of home made TPA3116 boom box (es). I was looking at ways to connect these two up to a single source, and after trying a splitter cable, decided to try pre-amplifier to boost input signal.

The result were that I destroyed my amplifier board and had to spend £7.50 on a new one. I would guess that these cheap amplifier boards are built to deal with a certain level of input power, and although the overall power was increased, and did not sound distorted, damage still occurred.

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The TPA 3116 board used  already has a pre-amplifier built in. 2 x NE5335 chips. I decided to try pre-amping gain using a Behringer HA400 Microamp, as stated above this did increase the volume considerably, but had I checked the temperature of components on the board I would have found that bad things were happening.

No doubt this post will annoy some people as I showed disrespect for the electrical engineer process, and ignorance of basic concepts, but I just like to try things out and see if it works.

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