Sound Skulptor forums

Build help and troubleshooting => MP573 Microphone preamplifier => Topic started by: Petrosa on April 13, 2023, 10:29:44 PM

Title: Power Strip did not start
Post by: Petrosa on April 13, 2023, 10:29:44 PM
Hello,

for the pleasure of having your modules as a live vocal chain, ich bought a Radial Power Strip (500mA) for three units.

I put the MP573, a EQ573 and a Elysia MPressor in it. All Units have less than 100 mA power consumption, but when i start it up, the powersupply tuns off after a second, turns on again for a second and turns off again, and so on.

I guess that there is too much power consumption when the units start up. When i remove the preamp or the eq, the powersupply stays on.

Is it possible that the slow start of the mp573 is damaged? Is there a way to fix it? Are there other possibilities to run this combination of modules in the Power Strip? There are no other options for three units in a one HE rack, maybe you should do one, i would buy it :D

Thanks in advance 

Simon

Title: Re: Power Strip did not start
Post by: JPK on April 14, 2023, 06:25:42 PM
The slow start is a current limiter made of U1 (LM317T) and R27 (7R5).
The inrush current is limited to 170mA.
Replacing R27 by a 10R would limit the current to 125mA.
Replacing R27 by a 12R would limit the current to 100mA.
I would not go higher because it would affect the sound when approaching saturation.