So here is the difference in the way the V2 mounts vs. the stock preamp.
The stock pre mounts facing the front of the amp to studs in the back plane of the chassis.
This exposes it to all kinds of interference (and faces the power amp board). It is especially noisy when sitting right next to a tube amps power transformer side. Dumb. AF. Especially for a single sided board mounted in an open chassis.
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The V2 is firmly mounted to the backside of the pots. It also has solid polygon ground plane pours on both sides of the board. The exposed side is now facing down and is oriented with its tiny side profile at at a right angle to the power supply board EMF.. and is much smaller so it's offset forward and to the left a good bit. It is quiet as a mouse ..even right next to a huge tube amp power transformer lit up.
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