Several people have been in touch lately with questions on how to modify the PCB into something it isn't right now. Popular requests are balanced inputs and/or balanced outputs, and DC servo on the outputs.

The instructions give you three alternatives for powering the Muffsy Phono Kits. Here's another one:

This step-down power module is available on Tindie, and can provide up to two amperes of power. Use two of them and connect a 15V DC power supply at VIN/GND as shown in the picture above, and you will...

UPDATE:

Since only one extra resistor value is needed to get the higher impedances, it's been added to the kit. Now you can choose between these two options.

The input impedances on the Muffsy MC Head Amp can be changed to your liking. To help you find the right values, here's a nifty input impedance ...

NOTE:

This modification is only intended for the Muffsy Phono Preamp together with the Muffsy Power Supply and Back Panel in the recommended B0905 enclosure. Before you try this, have a look at the other ways of eliminating hum.

Arno just completed building the Muffsy Phono Preamp, and was haunted by...

In Copenhagen, just across The Bridge from me, lives slowdiyer. He has designed the Muffsy Clone, his own version of the Muffsy that suits his needs exactly.

It is a mono version with single instead of dual op amps, which lets you use op amps like LME49710, LT1063, LT1028, AD797, OPA627 and more.  B...