I asked Spector VP, PJ Rubal, about this a while ago...this is an excerpt of his reply back.
"correct our 18v circuit is bass and treble. you see that mid option there because I have been working with
our circuit guy to add a mid option....well to be more accurate for years he and I have been trying to find the time
to work on the mid option LOL. I am not sure when or if that will ever happen."
Clearing out the parts drawer. Here's the goods.
PM Sent 18v US Spector circuit. View attachment 782465View attachment 782467
The preamp used in the US made NS-4, NS-5XL, etc... Master volume, pickup balance, stack bass/treble controls. Installation hardware and knobs included. $140.
-Set of (4) Black 2x2 tuners. View attachment 782458
Gotoh GB7 style, Made in Korea. Good condition, works great - no tuning issues, simply replaced these for gold tuners. Small screws not included. $20.
-Black 4 string bridge. View attachment 782459
0.70" (17.78mm) spacing. Common bridge found in imports. Used/fair condition. 5 hole, screws included. $10.
SOLD-Pair of EMG 40HZ dual coil pickups. View attachment 782455
4.0" x 1.5', Solder set, plenty of lead. Screws included. $45.
SOLD-Pair of Spector SSD dual coil pickups. View attachment 782457
EMG 35 size, 3.5" x 1.5". Screws included. $20.
SOLD-Mighty Mite MM114 9v preamp, Korean made "HAZ" copy/clone. View attachment 782463
Master volume, pickup balance, bass, and treble controls. These preamps get very close to the coveted 9v Spector circuit - the 'HAZ'. Installation hardware included. $50