Member of the Trade: AMB Laboratories
- Apr 1, 2004
The PPAv2's output transistors are rated for continuous 1.5A (BD139/140) or 4A (MJE243/253). There are 2.2 ohm emitter resistors that would help limit the current in a short circuit. There is also current limiting in the PSU (The LM317 regulator for example will current-limit and shut down if the draw is over 1.5A). As long as you don't keep the short circuit condition persist over a long period of time while the music is playing loud, then there should be little risk of damage to the circuit. If you're really paranoid, add a fuse at the DC power input.