Buffer pre or active pre...

No, it's not about passive pre.

it's about the same amplifier design which has 4 6922 (active) and another one with 2 6922 (buffer).

I don't know how to call this buffer or buffer with gain but certainly the 2 tubes need a little more crank of volume to sounds like 4 tubes.

Thanks all..

These two pre are based on MFA ref MC one. My friend made this with high quality printed circuit board (great skills he got).

OK, about the gain I think I don't have any issue. I'm using VTL MB250 signature (250wpc) with Naim CD5/Fcap2. After extensive listening I still can't make up my mind on which to go.