Thanks Jimy,
And you know, what I describe above is just what I've done. With all the options available from these instruments - including our active Q controls, stereo out to different amps and/or effects processing - everybody can dial in their own unique sound. There's no right way there's only your way.
You've spotted my aluminum blocks... This happened more or less by accident and here comes the boring story.
The first 5-string I got was in 1976 which was early for the low-B. At that time GHS was selling single gauges of their hilariously named Boomers including a very heavy E-string @ .120. So I used that along with their normal set: .45, .65, .85, .105 to string the bass.
Due to the type of string, the gauges, and the way I like to set up my action, I couldn't quite get the bridge to intonate correctly. I needed to move a couple of the saddles further towards the tailpiece but had run out of room. So the answer was to relocate the bridge about 1/4 in that direction.
My dad had a great shop full of tools including tap and die sets, etc. He did not have a chunk of brass the size of our bridge block but he did have some aluminum so we used that to make a replacement block with offset bridge mounting holes. We didn't know if or how it might effect the sound, and truthfully I still can't say what effect the change of material has. But I loved that first 5-string so every subsequent fretted bass I ordered from Alembic was built with an aluminum bridge block.
I'm sorry but I can't remember why the recording bass has a double-sized block. We must have been going for something but I haven't got a clue. HA!! Whatever the reason, I do like the sound of that bass.
Best to everybody,
Jimmy J