Minimalist Soft Start for 2sk170 Preamp

[DreadPirate]

This is a diy board from jimsaudio. Makes a gawdawful noise coming on. I know I can turn it on before the amp, but accidents do happen. So, is there a simple way to reduce this noise? The circuit is powered by 24vdc. A very very simple circuit I could build myself would work, but would need to have no more than 6 or so devices, these built up boards seem to take me hours to put together...

[bear]

Let's have a look at the circuit?

The simple way to handle this is to put a small relay that shorts the output to ground when there is no power on... then build one of the many circuits that do relay control/time delay and have it turn the relay on, opening it after the requisite amount of time...

There are three main variants: transistor + cap charging; 555 timer; TTL

You can find them all by searching on Diyaudio...

_-_-bear

[Glowbug]

I was looking at SY's Heretical Preamp design, and I noticed he used a relay to act as a dethumper; but even looking at the schematic, it's not exactly intuitive to how it's wired up.

If anyone had a picture of something like this out there, that might be helpful