Which Audio Cable Do I Need? A Guide to Matching Connectors

August 4, 2026

which-audio-cable-do-i-need-buying-guide

Which Audio Cable Do I Need? A Guide to Matching Connectors

Choosing an audio cable involves more than finding two plugs that physically fit.

The cable must also suit the signal being carried. Your connection may be analogue or digital, mono or stereo, balanced or unbalanced, and microphone, line or speaker level.

At Wiltronics, we stock audio leads, adaptors, connectors and bulk cable for home entertainment systems, recording equipment, public-address systems, musical instruments, computers and electronics projects.

In this guide, we explain how to identify the connections on your equipment and choose the right cable without getting lost in unnecessary technical detail.

Browse our complete range of audio cables, including 3.5mm, RCA, XLR, jack, MIDI and optical options.

Our quick recommendation: Identify the output on the source device and the input on the receiving device. Then confirm whether the connection is analogue or digital, mono or stereo, balanced or unbalanced, and line or speaker level.

Quick Audio Cable Selector

What are you connecting?	Typical cable or adaptor
Phone, tablet or computer to powered speaker	3.5mm stereo plug to 3.5mm stereo plug
Phone or computer to a Hi-Fi amplifier	3.5mm stereo plug to 2 × RCA plugs
CD player or Hi-Fi component to amplifier	2 × RCA plugs to 2 × RCA plugs
Microphone to mixer or audio interface	XLR female to XLR male
Microphone to compatible 6.35mm balanced input	XLR female to 6.35mm TRS
Mixer or interface with balanced jack connections	6.35mm TRS to 6.35mm TRS
TV to compatible soundbar or amplifier	TOSLINK optical cable
Combined headset plug to separate computer sockets	TRRS headset adaptor
Amplifier to passive speakers	Speaker cable
Musical keyboard or controller to computer	Compatible MIDI-to-USB interface

These are common combinations rather than universal rules. Always check the labels and specifications for both devices before ordering.

Step 1: Identify the Output and Input

Start with the equipment rather than the cable.

Find the output on the source device and the input on the receiving device.

A source may be a:

Television
Smartphone
Computer
Microphone
Musical instrument
Mixer
Media player
Audio interface
Amplifier

The receiving device may be a:

Powered speaker
Soundbar
Amplifier
Mixer
Recorder
Computer
Passive speaker
Pair of headphones

Look closely at the connector shape and nearby labels. Common markings include:

Headphone
Audio out
Line out
Line in
Mic
Optical
Digital audio
Left and right
Speaker out
MIDI in or out

Do not assume that similar-looking ports perform the same function. A 3.5mm microphone input, headphone output and four-pole headset socket may look almost identical while using different contacts and signal arrangements.

Step 2: Check the Signal Type

Before selecting a cable, answer four questions.

Is the Connection Analogue or Digital?

Analogue audio cables carry a continuously varying electrical signal.

Common analogue connectors include:

3.5mm jacks
RCA connectors
6.35mm TS and TRS jacks
XLR connectors

Digital audio transmits encoded data between compatible devices. TOSLINK is a common optical digital-audio connection used with televisions, soundbars and home-cinema equipment.

For more background, read our guide to how audio cables affect sound and signal transmission.

Is the Signal Mono or Stereo?

A mono connection carries one audio channel.

A stereo connection carries separate left and right channels.

One 3.5mm TRS lead commonly carries unbalanced stereo audio. Professional systems may instead use two balanced cables, with one carrying the left channel and another carrying the right.

Is the Connection Balanced or Unbalanced?

Balanced connections are commonly used with microphones, mixers, audio interfaces and professional sound equipment. When the complete connection supports balanced operation, it can reduce noise picked up along the cable.

Common balanced connectors include:

Three-pin XLR
6.35mm TRS

However, the connector alone does not guarantee a balanced signal. The output, cable wiring and receiving input must all support balanced operation.

Common unbalanced connections include:

3.5mm stereo
RCA
6.35mm TS

Is It Line-Level or Speaker-Level?

Line-level connections carry relatively low-level audio between equipment such as media players, mixers, amplifiers and powered speakers.

Speaker-level connections carry amplified power from an amplifier to passive speakers.

Do not use lightweight line-level audio cable as a substitute for appropriately selected speaker cable. Browse our audio and speaker cable range for amplifier-to-speaker wiring.

3.5mm Audio Cables

The 3.5mm connector is widely used with headphones, computers, portable speakers and consumer audio equipment.

3.5mm TRS Stereo

A standard 3.5mm stereo connector has three conductive sections:

Tip
Ring
Sleeve

In a typical stereo headphone or auxiliary connection, these carry left audio, right audio and common ground.

Our 3.5mm Stereo Plug-to-Plug Cable is available in multiple lengths for compatible speakers, computers and audio equipment.

For short connections, consider the 50cm 3.5mm Stereo Patch Lead.

Choose a 3.5mm Stereo Cable For:

Computer audio output to powered speakers
Portable player to car auxiliary input
Headphone connections
Tablet to compatible amplifier input
Laptop to portable speaker
General auxiliary audio connections

Some newer phones and tablets require a separate USB-C or Lightning audio adaptor.

3.5mm Extension Leads

When the existing cable is too short, a male-to-female extension provides a cleaner solution than chaining several adaptors.

Options include:

TRRS Headset Connections

A TRRS plug has four conductive sections and may carry stereo headphones plus a microphone through one connection.

This format is common with headsets used for laptops, gaming systems, phones and video calls.

The TRRS-to-Stereo-and-Microphone Adaptor separates a compatible four-pole headset connection into individually labelled headphone and microphone sockets.

For sharing one stereo output between several listeners, consider the Five-Port Stereo Headphone Splitter.

TRRS wiring standards can vary, so confirm compatibility with the device and headset before purchasing.

2.5mm and 3.5mm Conversion

Some compact or older equipment uses a 2.5mm audio connector.

The 2.5mm-to-3.5mm Stereo Plug Cable can connect compatible equipment with different jack sizes.

Browse our wider 3.5mm plugs, sockets and adaptors for inline, panel-mount, right-angle and conversion options.

Connecting 3.5mm Audio to RCA

A 3.5mm-to-RCA lead is one of the most useful audio conversion cables.

It normally converts a stereo 3.5mm output into separate left and right RCA connections.

Common Uses

Computer to Hi-Fi amplifier
Phone or tablet to stereo system
Media player to powered speakers
Laptop to mixer or amplifier with RCA inputs
Single-board computer audio output to compatible equipment

Available options include:

stereo-plug-3-5mm-2-rca-plugs-audio-cable-3m

Check Whether You Need Plugs or Sockets

A cable with two RCA plugs connects directly to RCA sockets on equipment.

An adaptor with RCA sockets accepts another RCA cable.

Suitable options include:

Check both connector type and gender before ordering.

RCA Audio Cables

RCA connectors are common on amplifiers, Hi-Fi equipment, televisions, media players and consumer audio products.

Analogue stereo RCA connections normally use a pair of plugs:

White or black for the left channel
Red for the right channel

Choose an RCA Cable For:

CD player to amplifier
Media player to receiver
Turntable preamplifier to compatible line input
Television analogue output to amplifier
Audio processor to consumer Hi-Fi equipment

Use a 2×RCA Plug-to-2×RCA Plug Audio Cable when both devices have matching left and right RCA sockets.

Browse our RCA audio plugs and sockets for line sockets, chassis connectors, PCB-mount sockets, joiners and custom cable parts.

Analogue RCA vs Digital Coaxial

The same physical RCA connector may also be used for a digital S/PDIF connection.

A red-and-white RCA pair normally carries analogue left and right audio. A single digital coaxial socket carries a digital signal between compatible devices.

Always check the labels rather than choosing solely by connector shape.

6.35mm TS and TRS Cables

The 6.35mm jack is common on musical instruments, mixers, amplifiers, headphones and professional audio equipment.

It is also known as a quarter-inch jack.

6.35mm TS

A TS connector has:

Tip
Sleeve

It commonly carries an unbalanced mono signal.

Typical applications include:

Electric guitar to amplifier
Keyboard mono output
Effects-pedal connections
Unbalanced line connections
Some microphones and PA equipment

For a compatible TS-to-RCA connection, consider the Redback 6.35mm TS Jack-to-RCA Cable.

6.35mm TRS

A TRS connector has:

Tip
Ring
Sleeve

It may carry:

Balanced mono audio, or
Unbalanced stereo audio

The connector shape alone does not reveal which format is being used.

For compatible balanced audio equipment, use the Redback 6.35mm TRS-to-TRS Cable.

TS and TRS Are Not Automatically Interchangeable

A TRS plug may physically fit a TS socket, but that does not guarantee correct signal routing.

Possible issues include:

One channel missing
Reduced audio level
Phase cancellation
Noise
Incorrect mono or stereo operation

Confirm the required wiring and signal format before ordering.

Browse our wider audio plugs and sockets for solder-termination plugs, panel sockets, right-angle adaptors and jack conversion products.

XLR Cables

Three-pin XLR is the standard connection for many microphones, mixers, stage boxes, interfaces and public-address systems.

A conventional microphone cable normally uses:

Female XLR at the microphone end
Male XLR at the mixer or interface end

Our Redback XLR Male-to-Female Cable is available in multiple lengths.

Choose XLR For:

Microphone to mixer
Microphone to audio interface
Balanced output to balanced input
Stage and PA connections
Recording setups
Longer compatible cable runs

XLR to 6.35mm TRS

Some equipment provides a balanced 6.35mm TRS input rather than an XLR input.

The Redback Female XLR-to-6.35mm TRS Microphone Cable is intended for compatible balanced microphone connections.

Before using one, confirm that the 6.35mm socket is:

An input
Wired for TRS
Compatible with the source level
Appropriate for the microphone or equipment

The cable does not provide microphone preamplification, phantom power or automatic level conversion.

Loose XLR Connectors

For cable repairs and custom assemblies, we stock products such as the Neutrik NC3FXX Three-Pin Female XLR Connector.

Browse our wider XLR connectors and adaptors for line plugs, chassis sockets and conversion products.

XLR and RCA Conversion

XLR and RCA commonly represent different signal arrangements and levels.

A simple cable may physically connect the equipment but may not resolve:

Balanced-to-unbalanced conversion
Level differences
Ground-loop hum
Impedance mismatch
Electrical isolation requirements

For compatible systems, consider:

TOSLINK Optical Audio

TOSLINK uses optical fibre to carry digital audio between compatible devices.

It is commonly found on:

Televisions
Soundbars
AV receivers
Media players
Game consoles
Digital audio processors

Our TOSLINK Optical Audio Lead is available in several lengths.

Choose TOSLINK When:

Both devices have optical audio ports
A TV needs to connect to a soundbar
An optical output needs to connect to an AV receiver
Electrical isolation between devices is useful
Both products support a compatible audio format

TOSLINK does not automatically improve every system. The source and receiving devices must support the same digital-audio format, and their settings may need adjustment.

Optical Cable Accessories

Our optical audio cable range includes:

A right-angle adaptor can help where clearance behind wall-mounted equipment is limited.

Speaker Cable Is Different from Line-Level Audio Cable

Passive speakers require an amplified output from a compatible amplifier.

Speaker cable carries more current than a microphone, auxiliary or line-level connection. Select it according to:

Speaker impedance
Amplifier output
Cable length
Conductor size
Installation environment
Connector or terminal style

Browse our audio and speaker cable range when wiring compatible passive speakers.

Powered vs Passive Speakers

A powered speaker contains its own amplifier and normally accepts a line-level input.

A passive speaker requires an external amplifier and connects to the amplifier’s speaker output.

Do not connect a line-level source directly to a passive speaker and expect normal operation. Likewise, do not connect an amplifier’s speaker output to an ordinary line-level input.

Speaker Terminations

Our banana plugs, sockets and binding posts include:

Gold-plated banana plugs
Stackable banana plugs
Screw-termination plugs
Binding posts
Speaker terminal assemblies
Panel-mounted sockets

Choose connectors that match the amplifier and speaker terminals.

Adaptors, Splitters and Conversion Leads

An adaptor can be useful when the signal format is already compatible and only the physical connector needs to change.

Examples include:

3.5mm to RCA
3.5mm to 6.35mm
TRRS headset splitter
TOSLINK joiner
XLR-to-TRS cable
Right-angle adaptors

An Adaptor Does Not Necessarily Convert the Signal

A passive adaptor usually changes the connector arrangement only.

It may not provide:

Digital-to-analogue conversion
Analogue-to-digital conversion
Microphone preamplification
Phantom power
Impedance matching
Balanced-to-unbalanced isolation
Headphone amplification

Check whether your setup requires an active converter, interface or isolation device.

MIDI Cables Do Not Carry Audio

MIDI transmits performance and control information rather than sound and can tell compatible equipment:

Which note was played
How hard it was played
When it was released
Which sound or program to select
How a controller was moved

The MIDI-to-USB Cable can connect compatible MIDI equipment to a computer.

The actual audio from a keyboard or synthesiser must leave through a separate audio output or interface.

Check whether your equipment uses:

Five-pin DIN MIDI
USB MIDI
3.5mm MIDI
A manufacturer-specific adaptor

Ready-Made Leads or Custom Cable Assemblies?

Choose a Ready-Made Lead When:

Both connector types are known
A standard length is suitable
The equipment uses common ports
A moulded cable offers the required durability
No permanent installation is needed

Choose Bulk Cable and Loose Connectors When:

A custom length is required
Cable must pass through an installation route
A panel connector is being fitted
Existing cabling needs repair
A specialised connector combination is required
The installer has appropriate assembly and testing skills

Our bulk-cable selection includes Four-Core Shielded Audio Cable for suitable microphone and general audio circuits.

Custom cables should be assembled with correct wiring, insulation, strain relief and testing.

How Long Should an Audio Cable Be?

Choose a cable long enough to follow a safe route without pulling on either connector.

Avoid purchasing excessive length merely for convenience. Unused cable can:

Create clutter
Become tangled
Increase trip hazards
Make fault finding harder
Place strain on connectors when tightly coiled

For unbalanced analogue signals, shorter practical runs can also reduce exposure to interference.

Balanced connections are generally preferred for longer compatible microphone and line-level runs, but the entire connection must support balanced operation.

How to Reduce Hum and Interference

Noise is not always caused by a faulty cable.

Possible causes include:

Unbalanced leads near power equipment
Damaged shielding
Loose connectors
Ground loops
Incorrect gain settings
Incompatible signal levels
Poor power supplies
Faulty source or receiving equipment
Audio cables routed alongside mains leads

To reduce problems:

Use the correct cable type.
Keep audio leads away from power transformers and mains cables where practical.
Use balanced connections when both devices support them.
Avoid unnecessary adaptor chains.
Check that every plug is fully inserted.
Test with a known working cable.
Replace damaged or intermittent leads.
Use an appropriate isolation device when a ground loop has been confirmed.

Testing Audio Cables

A cable can look undamaged while containing:

Broken conductors
Intermittent contacts
Shorts between terminals
Incorrect wiring
Damaged shielding

The 13-Way Audio/Video Cable Tester supports several common audio and AV connector formats.

Cable testing is useful for:

Stage leads
School equipment
Recording studios
Hire inventory
Custom cable assemblies
Frequently handled microphone leads
Fault finding before an event

Label tested cables and remove unreliable leads from service.

Common Audio Cable Buying Mistakes

Choosing Only by Plug Shape

Two connectors may fit while carrying incompatible signals.

Check the port function, signal type and direction.

Confusing TS and TRS

TS commonly carries unbalanced mono audio. TRS may carry balanced mono or unbalanced stereo.

The equipment determines the actual use.

Assuming XLR Automatically Means Microphone Level

XLR connectors can carry microphone, line-level, digital or control signals depending on the equipment.

Read the port label.

Using an Adaptor Instead of a Converter

A passive adaptor does not normally convert between analogue and digital audio.

An active converter may be required.

Connecting Passive Speakers with Line-Level Cable

Passive speakers need an appropriate amplifier and speaker cable.

Assuming MIDI Carries Sound

MIDI carries instructions rather than audio.

Ignoring Connector Gender

Check whether each end requires a plug or socket.

Buying the Longest Cable Available

Choose enough length for a safe route with a modest allowance rather than creating an unnecessary coil.

Expecting TOSLINK to Support Every Format

The source and receiving equipment must support a common digital-audio format.

Building a Chain of Adaptors

Multiple adaptors add connection points and increase the risk of incompatibility or intermittent contact.

A purpose-made cable is often the cleaner solution.

Audio Cable Buying Checklist

Before ordering, confirm:

What is the source device?
What is the receiving device?
Which connector is on the output?
Which connector is on the input?
Does each end require a plug or socket?
Is the signal analogue or digital?
Is it mono or stereo?
Is it balanced or unbalanced?
Is it microphone, instrument, line or speaker level?
Does the cable need separate left and right channels?
Do both devices support the same digital format?
Is an active converter required?
What cable length is practical?
Will the cable be moved frequently?
Is a right-angle connector needed?
Does the installation require a ready-made lead or custom cable?
How will the finished connection be tested?

Frequently Asked Questions

Which cable connects a phone or computer to an amplifier?

When the source has a 3.5mm stereo output and the amplifier has left and right RCA inputs, use a 3.5mm stereo-to-2×RCA cable.

The source may need a USB-C or Lightning audio adaptor if it does not have a headphone socket.

Is RCA or 3.5mm better?

Neither connector is automatically better.

Choose the option that matches the equipment. Both are commonly used for unbalanced analogue audio.

Is XLR better than TRS?

XLR and TRS can both carry balanced mono audio when the cable and connected equipment support it.

The best choice is normally the connector provided by the equipment.

Can a TRS cable carry stereo audio?

Yes. A TRS connection can carry unbalanced stereo audio.

It can also carry balanced mono audio in another application, so check the device specifications.

Can I connect an XLR microphone to a 6.35mm input?

An XLR-to-6.35mm cable can be used where the equipment connections, wiring and signal levels are compatible.

The cable does not add a microphone preamplifier or phantom power.

Which cable connects a TV to a soundbar?

Use a TOSLINK optical lead when both devices have compatible optical ports.

Other systems may use HDMI ARC or eARC, depending on the equipment.

Can I split one optical output into two?

A passive TOSLINK splitter can physically divide an optical signal, but compatibility, signal strength and cable length still matter.

Can I use a guitar cable as a speaker cable?

Do not assume an instrument cable is suitable for an amplifier-to-speaker connection.

Use cable designed for the amplified speaker signal.

Does MIDI carry sound from a keyboard?

No. MIDI carries performance and control information.

The keyboard’s audio output requires a separate audio connection.

Why does my audio cable hum?

Possible causes include a damaged cable, unbalanced connection, ground loop, poor routing, incompatible equipment or incorrect gain settings.

Test with a known working cable and simplify the connection before adding adaptors or isolation equipment.

Match the Cable to the Equipment

The easiest way to choose an audio cable is to begin with the two devices.

Identify the source output and receiving input, then confirm the signal type. Only after those details are known should you select the connector combination and cable length.

Use 3.5mm for compatible headphones, computers and auxiliary connections. Choose RCA for many consumer Hi-Fi components, XLR or TRS for compatible balanced professional equipment, and TOSLINK for supported optical digital-audio connections.

Use dedicated speaker cable between an amplifier and passive speakers, and remember that MIDI carries control data rather than sound.

Explore our complete selection of audio cables, 3.5mm plugs and sockets, RCA plugs and sockets, XLR connectors and adaptors, optical audio cables, audio and speaker cable and banana plugs and binding posts.

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