There's a lot ... er, that's an understatement ... of heated debate as to what gets you that SRV sound. Well here's my five pence worth: 60% in those great, powerful hands of his ... gotta learn his chops and phrasing. 20% in clonking great strings ... and 20% in the pickup/amp combination.
With the pickups you need clarity, lots of overtones and plenty of midrange growl. But you mustn't sacrifice the sparkle on the top end to the god of high output! The tone should be huge, but without as much overdrive as people think.
My Triple Blues set is probably not made in anything like the way No.1's pickups were ... for a start they have flush pole pieces for added mid boost and string definition. They are wound 6k, 6k, and 7k (neck to bridge ... and figures are average) so they are only a smidge hotter than standard, and they have a RWRP middle pickup so switch positions 2 and 4 are hum cancelling.
So ... do they sound like SRV? Well to my ears there's all that twang and aggression ... and with a valve amp coupled with a good overdrive - set to full level, minimum drive - there's that scream too.
My own Strat has a set of these now ... I sold my Japanese Fender pickups as soon as I heard the Triple Blues ... confidence in my product OR WHAT?