Bartolini piezo buffer mpb1 vs mpb2

[ChrisPbass]

Does anyone know the difference between the MPB1 and MPB2?

longstory short, I have the MPB1 which says (bass boost on piezo channel).
I'm told the 2 is better for bass.
It is not installed yet.

Any thoughts, experience?

Thanks!

[SGD Lutherie]

The MPB1 has an input impedance of 390k on the magnetic channel, while the MPB2 has an input impedance of 1M. The MPB2 will give a brighter tone from the magnetic pickups. The MPB1 will sound darker. Most bass amps have an input impedance of about 1M, but you also have your cable and controls to factor in on passive basses, so the MPB1 might sound more "passive".

Both buffers have an input impedance of 3.3M on the piezo channel.

[ChrisPbass]

Modulus bass
Bart passive pups
Bart ntmb w active passive switch
Eden wt 400
I also use a thumpinator which is a hpf but has buffer properties too I believe