RBX765a wiring and pickup modification queries

[billybigbass]

Hello,

I have a late 90s Yamaha RBX765a 5 string i acquired this week. It's in very nice shape but the electrics have been redone to make it passive instead of active (as it was orginally) and the front yamaha pickup has been replaced with a Kent Armstrong.

Some queries on the electronics.

Original wiring for this model's 4 pots (for 2 pickups) was volume / bass / treble / pickup blend per attached drawing.

Currently it has been wired for master volume / front pup volume / rear pup volume / tone.  The wires to the battery compartment are snipped so unconnected. Neither of the individual pup volumes work without the master volume turned up first. Dont like it like this. See photo, annotated T tone MV master volume, V volume x 2.

Looking to restore back to either original arrangement or go for 2 volumes and 2 tones and do away with the master volume.  

 The 3 volume (yes 3!) pots are rated B500k and the tone pot A500k, all made in Japan. I dont know if these are original pots (guessing not).

Can I change this without replacing pots? Or do tone pots always have to have a capacitor on them?

Looking further ahead I may look to the EMGs solderless 45 size pups if teh above doesn't work out. I like the neck on this 5 string so much it's likely a keeper and happy to upgrade in time. The pup cavities are the size of the EMG45 6 string range but as long as it's a bar magnet rather than poles it will work fine for a 5 string, I understand? 

If I was getting a pair of the EMG45 pickups is it right that some cant utilise a pickup blend pot, they need separate volume and tone controls?

Anyone advise what they think is best would be appreciated.

 

thanks

 

Edited July 3, 2021 by billybigbass

[hubrad]

EMG do VVTT as standard, but they do an active blend control which gets round the loss in middle position if you want to stay with passive tone controls. I prefer the whole system with Vol, Blend and active 2 band. Really versatile!