Hi everyone,
 
Can anybody tell me the fundamental differences between the series one and series two electronics?
 
Cheers, Andy.

Hey Andy,
 
Both are 18 volt-powered (via batteries or DSR5 power supply), stereo/mono, single coil pickup-driven systems.  Each has a separate pu selector switch (4 position).
 
Here are the differences:
 
Both have independent controls for each pu:
Vol, (low pass) filter and Q - but the S1 has a 3 position Q switch where the S2 has a continuously variable Q (dial).  Each Q adjusts the amount of volume boost applied to the top cutoff frequency at which the low pass filter is set. I've heard very few folks say the difference between the 3 pos'n Q and the CVQ is very big.  
 
The S2 has a master volume control, while the S1 does not.  I find the master volume handy.  This is because when you tweak the pu volumes to vary the mix of signals coming from each, the overall volume changes.  The master volume lets you control the guitar's volume with a single dial.  That way, the pu volumes can be used strictly for tone shaping.
 
Despite the differences, each is capable of basically the same sounds.  
 
Bill
 

Hi Bill,
 
Thanks for the insight. Most appreciated.
 
Best Regards, Andy.

Andy and Bill,
 
the CVQ boosts to + 15db max and is a pot.
the 3 position Q boosts has +0db, +6db and I THINK +12db (or + 9 db ).
 
Paul TBO

Paul; I believe it's 0, 6, and 9.

Hoi Brother Dave!
Yep ...but I THOUGHT ...not sure ...I know ...I am never sure but somewhere there is that little voice singing. That signatures had a 0, +9 +12db jump (like the series 1) and the normal 3 position switches where 0 +6 and +9.
Dave ...I KNOW you are a master-searcher so I leave it up to you!
 
Paul TBO

Hah!!  I have to admit that I'm relying on my memory here; and that I could be wrong, my memory being as poor as it is.  I'm facing a work deadline and thus haven't done the search.