Low rider vs Pearl OC-07 ocatver

[garfo]

I have made an older version of the Low Rider and compared the Octave Down vs the Octave down on my original Pearl OC-07.
They do not sound the same and it's killing me.

The Pearl has an hollowness and gritiness to the sound that the Low Rider does not have. The original Pearl has this kind of synthy quality to it while the Low Rider is cleaner and fater (it doesn't sound bad, but it doesn't sound as good).
I used an MC14013 for the Flip Flop and an LM2902 for the Driver of the Flip flop (the original uses these two).

I have tried three different diodes, one OA91 (germ), D9E(germ) and a Bat46. They all seem to offer something different to the sound (hard to say exactly what) but with none of them I get any closer to the sound of the Pearl Octaver. The Low rider sounds a bit bassier and it's deinitely cleaner (less artifacts).
Any tips on why I am not getting similar results to the original? How important is the germanium diode to the sound? Is it the diode or is it something else that I am missing?