Step 8 — TRS Output Jack

WIRING SIDE (back of control plate)
TRS stereo jack · Tip = signal, Ring = +9V, Sleeve = ground
Buffer out → Tip · TRS Ring → Buffer +9V · GND bus → Sleeve
BUFFER Step 7 2N5457 JFET buffer OUT +9V GROUND BUS ← TIP RNG SLV TRS OUTPUT JACK Switchcraft stereo jack T TIP signal R RING +9V S SLEEVE ground Conductor 1 — Signal (Tip) Conductor 2 — +9V Power (Ring) Braided shield — Ground (Sleeve) TRS SHIELDED CABLE to pedalboard / amp · 2 conductors + braid → to amp 8.1 — BUFFERED SIGNAL (Buffer Out → TIP) from buffer Jack TIP 8.2 — +9V POWER (RING → Buffer +9V) Jack RING to buffer +9V 8.3 — GROUND (bus → SLEEVE) GND bus Jack SLV TRS vs TS Must use TRS (stereo) jack — Ring carries +9V phantom power for the buffer. CABLE REQUIREMENT Use TRS cable (2 conductors + braid). Standard guitar cable will not work. POWER ON/OFF Buffer powers on when TRS cable is inserted. Unplugging = off. No switch needed. CHECK: Buffer Out → TIP = continuity  •  RING → Buffer +9V = continuity  •  GND bus → SLEEVE = continuity  •  No shorts between T/R/S
Buffered signal (Tip)
+9V power (Ring)
Ground (Sleeve / braid)
Ground bus (context)
Buffer board (context)

Step 8 Instructions

  1. 8.1 — Identify the TRS jack terminals. A TRS (stereo) jack has three terminals: TIP (signal out), RING (+9V power in), and SLEEVE (ground). Verify which terminal is which before soldering — check with a multimeter and a TRS plug.
  2. 8.2 — Solder buffered signal to TIP. Run a wire from the buffer output (after the 10µF coupling cap) to the TIP terminal. This carries the low-impedance buffered signal to the cable.
  3. 8.3 — Solder +9V power to RING. Run a wire from the RING terminal back to the buffer’s +9V power input. Power arrives from the pedalboard/amp end via the cable’s second conductor. The RING connection means the buffer only powers on when a TRS plug is inserted.
  4. 8.4 — Solder ground bus to SLEEVE. Run a wire from the ground bus to the SLEEVE terminal. This completes the ground path from the bass electronics through the cable braid to the amp.
  5. 8.5 — Verify cable wiring. At the other end of the TRS cable: Tip conductor goes to amp input (signal), Ring conductor goes to +9V supply (e.g., pedalboard power), Sleeve/braid goes to ground. A mis-wired cable will send 9V into the amp input — double-check before connecting.
Continuity checks: Buffer Out → Jack TIP (signal). Jack RING → Buffer +9V (power). Ground bus → Jack SLEEVE (ground). No continuity between TIP, RING, and SLEEVE (no shorts). Critical: Verify cable pinout at both ends before first power-on.