Yamaha TRB4: question about upgrading electronics

[mcc]

Hi guys, I hope all of you are staying safe. 

I have a Yamaha Trb4 MK1 (two jazz pick-ups) and love everything about it .... except for the electronics. I have always though it sounds OK ... but just OK. I would love to get a more modern sound out of it and a broader palette (would love something like the Yamaha BB2004 I once had but regrettably ended up selling).

I have seen in a couple of TRB threads people that complained against the MK1 eq section branding it as noticeably inferior to the "upgraded" MKII and have seen many of these basses for sale with replacement electronics so I guess I'm not alone.

In the past, I have swapped pickups and electronics out with varying degrees of satisfaction. Sometimes it has been a "wow, this sounds like a completely different instrument" and others more like "meeee ... the difference is not that great". So I would like to get some guidance, even if it is subjective, on where the biggest improvement can be achieved. I would usually start with changing the pickups, but I have mostly upgraded basses that came with fairly cheap pickups and in this case it is not obvious for me, specially due to the bad press the eq section has received, that this is the best approach given that on paper the specs of the pickups look respectable. 

My question is: among those of you that have dealt with this model in particular and have swapped electronics, in your opinion, is the EQ section the weakest link, the pickups or both.

best, 

Marcus

 

[itu]

If you want to understand the basics of the signal chain, I wrote something to the following thread. It may help you a bit. Another thing is to understand the physical details, like pickup height, and the effect of strings (Ni vs. SS, flat/ground/round).

 

[Jakester]

I have a much later TRB and I’m fine with the electronics, but based on experience with other basses, one of the best things you can do is fit a John East preamp. 
 

Have a look here and there’s bound to be a configuration that will drop in:

https://www.east-uk.com/index.php/bass/u-retro.html

[ikay]

Have you tried tweaking the trim pots for the mid control in the control cavity? You can adjust the mid freq and the level of cut/boost if you're not happy with the factory settings. Might be worth having a play with that before replacing the preamp.

 

[Jakester]

Oh, and I think I read somewhere that some of the Yamaha pickups are a different impedance to 'normal' ones - the Yammy preamp buffers/boosts them but some aftermarket preamps don't work, so perhaps worth checking that out too, though if it's standard jazz-size pickups you'd be fine to change those (mine has non-standard soapbars).

[geoffbyrne]

16 minutes ago, ikay said:

Have you tried tweaking the trim pots for the mid control in the control cavity? You can adjust the mid freq and the level of cut/boost if you're not happy with the factory settings. Might be worth having a play with that before replacing the preamp.

 

^ This.

G.