AT-LP60X Headphone Mod
The Audio-Technica AT-LP60X is a decent automatic turntable that sells for about $150. It has one annoying gap: there's no headphone output. The line out on the back is meant to feed a separate amplifier, so it won't drive most headphones loudly enough, and there's no volume control on it either.
Audio-Technica sells a version of the same turntable with a headphone jack for $50 more, but I hacked in a headphone amp myself for cheap instead.
Technical Overview
The mod has three stages: power, amplification, and output. Power taps the turntable's existing 12 V supply and drops it to the 5 V the amplifier uses, using an LM2596S buck converter trimmed to 5 V. Amplification uses a MAX4410 headphone amp, which takes the preamplified output already present in the turntable and brings it up to headphone level. Output goes through a 3.5 mm jack board on the front panel.
The MAX4410 board comes with a potentiometer soldered to it. I desoldered that and reattached it on wires so it could mount through the front plate and act as a real volume knob. Two printed parts finish it off: a knob for the potentiometer and a holder that carries the jack board.
- LM2596S buck converter
- MAX4410 headphone amplifier board
- 3.5 mm jack PCB
- Printed knob and jack holder
While I considered adding bluetooth and USB for record digitization, I decided against it to limit the scope and cost of the project.
3.5 mm Breakout
The 3.5 mm breakout is a custom build. Generic breakouts from Amazon are expensive and low quality relative to what my simple custom board was able to achieve.
Build
You need normal hand tools plus a drill and a bit set.
- Disassembly. Take off the dust cover, felt mat, 45 RPM adapter, and the metal platter, watching the belt as you go. Put the dust cover upside down on something soft and rest the turntable on top of it, then remove every screw you can see. The bottom cover slides out. Disconnect the wire extensions, pull the buttons, and take off the foil shielding.
- Soldering. Cut five pieces of insulated wire around 10 inches long. Three go to the audio output jack and two to the power jack. Then desolder the potentiometer and the JST connectors from the amplifier board.
- Drill. Mark and drill a 1/2 inch hole and a 1/4 inch hole in the front plate, plus matching holes in the frame behind it. Start with a small pilot hole. The potentiometer hole usually needs chamfering, because there's an alignment bump on the front of the pot body that stops it sitting flush, and the plastic is thick enough that the threads don't reach through. An X-Acto knife handles both.
- Wire. Solder the jack board together and superglue it into its printed holder, then run wires from the board to the output pins on the amplifier. Reconnect the potentiometer to its footprint on the amp board using urethane coated copper wire. Trim the buck converter to 5 V first, on the bench, with a 12 V source and a multimeter. Then wire the turntable's power to the buck converter, the buck converter to the amplifier, and the audio wires into place.
- Assemble. Superglue the jack into its hole in the front plate, screw the potentiometer in and add the nut, then hot glue the boards into whatever free space is left inside. Reassemble in reverse, putting everything back the way it came out.
Notes
Two things cost me time. The first is wire choice. I did the potentiometer with regular insulated wire, then went back and redid it with urethane coated copper, which is much easier to work with in that little space. Do it that way the first time.
The second is that once the potentiometer is off the board there's no way to tell its wires apart by looking. I sorted mine out with a multimeter. Label them as you go and you'll skip that.
Trim the buck converter before it's wired into anything. It's a two minute job on the bench and a bad one to discover afterwards.
Conclusion
It works and I still use it. The jack and knob sit on the front plate next to the existing controls and don't look bolted on, which was most of what I wanted.
The mod came out cheaper than buying the version of the turntable that already has the jack, though not by enough to call it a savings once you count the afternoon. The better reason to do it is that the AT-LP60X has plenty of empty space inside and a 12 V rail sitting right there, so it takes the modification easily.
Gallery
