Connecting a Guitar to an Aux Input the Right Way
A guitar cable to aux setup connects an instrument output to a consumer input built for a fraction of that voltage. The mechanical conversion is easy: a quarter-inch plug on one side, an eighth-inch plug on the other. The electrical conversion is where most of these attempts fail, because a pickup expects a high impedance load and a phone, camera, or mixer expects a line level signal. This guide covers the adapters and the level matching.
Quick Answer / Summary
Use a 6.35mm to 3.5mm adapter or cable with a TS plug at the guitar end and a TRS plug at the aux end. Guitar output is instrument level and high impedance, so a direct connection into an aux input sounds quiet and thin. An amplifier, a DI box, or an interface with a high impedance input supplies the load the pickup needs before the signal reaches aux.
Two Formats That Do Not Match
The guitar end is a 6.35mm TS socket expecting a high impedance source. The aux end is a 3.5mm TRS socket expecting a line level source at low impedance. Diameter and contact count can be adapted with a passive part; the impedance and level difference cannot.
What Each Input Expects
A guitar input presents roughly one million ohms and a signal of a few tens of millivolts. An aux input presents about ten thousand ohms and expects around one volt. Feeding the smaller signal into the larger expectation is the mismatch that makes direct connections sound weak.
Adapters That Work and Adapters That Fail
A cable with a molded 6.35mm TS plug and a molded 3.5mm TRS plug is the reliable option. A rigid adapter hanging out of a phone or camera jack is the common failure, because the lever arm stresses the socket. Avoid adapters that split one mono plug into two RCA or two separate jacks unless the destination really needs two inputs.
TS Into TRS Without a Short
A TS plug in a TRS socket connects the tip and ties the sleeve to ground, leaving the ring floating at the destination. Most aux inputs then feed both channels from the tip, which is the mono result you want. If the destination is a stereo mic input with plug-in power, check before connecting.
Level Matching Into a Consumer Input
The clean path is to raise the signal before it reaches aux. A pedal with a level control, a preamp, or a DI box brings instrument level up to something an aux input can use, and it also buffers the pickup so the cable no longer loads it. Set the pedal volume low at first, because an aux input on a phone or camera clips abruptly and the distortion is not obvious on small speakers. If the result hums, check that both devices share one power source and that no adapter is reversing the sleeve ground.
Recording Setups That Use the Conversion
The usual rig is guitar into a pedal, pedal into a camera or phone, with the adapter at the camera end. That works for reference audio and for video where the guitar is background. For a clean recording, use an interface with a high impedance instrument input and take the line output to the aux input only when a second device needs a feed. Keep the adapter cable short, tape the joint at the camera, and check levels with the loudest passage rather than a quiet phrase.
Comparison Table
| Setup | Cable or adapter | Level at aux | Notes |
|---|---|---|---|
| Guitar into phone | 6.35mm TS to 3.5mm TRS | instrument, very low | thin result, add a pedal or interface |
| Pedal into camera | 6.35mm TS to 3.5mm TRS | closer to line | set pedal volume low first |
| Guitar into powered speaker | 6.35mm TS to 3.5mm TRS | instrument, low | use the mic input instead |
| Interface line out to aux | 6.35mm TRS to 3.5mm TRS | line, matches | watch balanced to unbalanced |
| Guitar into mixer line in | 6.35mm TS direct | instrument, low | engage the pad and gain stage |
Table: Common guitar to aux connections
Practical Application Scenarios
- A creator records a guitar part into a phone through a pedal and an adapter cable for a quick video.
- A teacher feeds a guitar into a powered speaker and finds the aux input too quiet until a preamp is added.
- A venue tech takes a line output from an interface into a house aux input and pads the channel before the first sound check.
- A player keeps a short adapter cable taped to the camera rig so the joint cannot flex during a take.
Related Products and Further Reading
- jack cable catalog – Find 6.35mm to 3.5mm cables with molded ends.
- describe your recording chain – Get a recommendation for the adapter and plug types.
- conversion guide – How adapters change signal type as well as shape.
- guitar jack cable build – Why the instrument end uses a TS plug.
Frequently Asked Questions
Why is my guitar so quiet through an aux cable?
The pickup output is instrument level, far below the line level an aux input expects. Add a pedal, preamp, or interface with a high impedance input before the aux connection to raise the signal properly.
Do I need a stereo or mono adapter for guitar to aux?
Use a mono TS plug at the guitar end and a stereo TRS plug at the aux end. The guitar signal is mono, and the TRS plug lets both sides of the aux input receive it.
Can I plug a guitar straight into a phone headphone jack?
A headphone jack is an output, not an input, so nothing will record. Phones that accept audio input use the same jack with a four-contact plug or a separate adapter, and the level still needs raising.
Will a DI box help a guitar to aux connection?
Yes. A DI box buffers the pickup, balances the signal, and provides a level an aux or mixer input can use. It also lets you run a longer cable without treble loss.