Bass 1 - Overhaul
When I envisioned this bass, I chose a Single Music Man Style Pick-up linked to a 6 way rotary switch. This utilizes every possible wiring configuration for this type of unit.I also fitted a Kent Armstrong 2 band EQ, which in recent years has been a problem. I also didn't fit a proper Gohtoh battery box which has also been an issue. The active circuit isn't woring reliably, and there's been a huge drop in gain in the passive out put. I'm hearing a lot more noise then usual and the jack output is in the wrong place.
So a new stereo long barrel jack is needed. I've decided that the original Kent 2 band EQ needs to be retired. It's old and faulty and I have a brand new Bartolini 3 band sitting my me desk crying out for a bass to go into. This was supplied with a blend control, so that will need to be adapted to accept the output from the 6 way rotary. The controls are 3 pots. One for Volume, with a pull up for passive mode. A stacked Bass and Treble centre dented pot. The third pot is a mid control, centre dented with a pull up mid feq shift. I'm not sure how this will work, but I'm happy to give it a try.
So, first job is to strip it down and remove all the electrics. This is quite scary becuase I have completely forgotten how to wire guitar electrics and this bass is in a mess. I took loads of photos to remind me where and what gets soldered...it's a very easy to get confused and I really don't want to re-wire the 6 way rotary switch. This is the last time I'm going to use one of these. Nice, but a PITA to configure and wire up. In the future, I'm going for a simple 3 way switch offering series, parallel and single coil.
After seeing my bass in pieces and a very uneasy feeling in my stomach, it was time to rout out the control cavity depth. I didn't do a good job of this the first time around and I'm going to need all of the room and neatness I can impart here. I drilled out the new location for the jack socket and I've cut a fillet for the old hole. Notice that the old aluminium foil is mostly gone now.
Once routed, it was time to shield the cavity using sticky backed copper foil. This stuff is great becuase it's very pliable but stays put once shaped. It can be soldered too, so edges can be sealed with solder and wires can be soldered to it...which is a big bonus.
I think routed out the battery box, I made a simple template and used a template router bit to rout around the inside. This went well and was a neat job. Mahoganny is such an easy wood to work with. My router has a dust port and I hook my extraction fan on to this. A few times it fall off and sprayed router dust all over my garage.
I then fitted the battery box and started to fit the Bartolini 3 band EQ. Two of the pots have a thicker diameter so these needed drilling out. I fitted the battery terminals first, then soldered up all the earths. These I then soldered to the jack, and then I refitted the pickup and 6 way rotary knob and soldered these back together. I then soldered the 6 way rotary output to the bartolini circuit and fitted all the parts carefully inside. It's pretty jambed in and no spare room at all. I kind of wished I've enlarged the cavity a bit more so I could neaten every thing...but maybe I'll do that when I come to overhaul this bass again.
I finished up with a quick field test and then a new set of Hot Wire bass strings...nice.
The Bart circuit sounds pretty much the same as the old kent circuit. The mid freq is a little low at the moment, it seems to add a lot of boom. But it's working nicely. All the popping and hum is gone and I can stand right in front of my rig at high volume and it's completely free from hum and feedback...perfect! The gain is back again too...in fact the output is remarkably loud. All in all, I'm calling this a big success.
It's a tight squeeze in there...but it all fits! I might shorten the battery leads at some point as well. They look a little long. I also need to shave down the wodden plug in the old jack socket hole (bottom right of the frame above).
The stack knob sticks out a bit more than the other knobs do, I'll have to be careful to protect this stack, it's a bit vulnrable. This is the most sophisticated electroncs / EQ I've yet to install. The 6 way rotary switch dials in either of the two single coils, series or parallel humbucker and phase options. The lowest knob is the volume, which is a pull up switch to enage passive mode. The left stack knobs are bass and trebal cut / boost, which are centre dented (nice). This pretty much does the same as my old Kent 2 band circuit. The left knob is the mid cut / boost pot with a pull up switch to shelve the mid frequency. The tonal pallet is vast and very expansive...although it always retains the same charector (wood / pickup / design choices).
From an asthestic point, of view, it doens't look all that different. I was considering fitting an addional Jazz pickup, but I descided not to because it would alter the looks and loose that fresh look which this bass has. It's my most used Bass and I like it's simplistic look. I'm going to build another 4 string bass to compliment this bass later this year.
With the new battery box installed, it's looking a lot neater around the back