3.5 mm vs Optical Audio Cable: Is There a Difference in Quality?

3.5 mm vs Optical Audio Cable

When it comes to hooking up an audio system or sound bar, having the right cables will ensure an uncompromised audio experience. Since cables are necessary for transmitting signals between devices, any possibility of signal interference or degradation can have a significant influence on sound quality. There are many different kinds of audio cables that are utilized in sound system setups. Optical and 3.5mm audio cables are two of the most common types of audio cables. However, do you know how they vary? What uses do they have? What do they look like, and how do they function? And most importantly, between 3.5mm and optical audio cables, which one delivers audio transmission of greater quality? Well, that’s exactly what we’re going to discuss in this article. 

3.5 mm Cable

The 3.5mm audio cable is used to transmit audio signals between two devices that accept multiple 3.5mm connection types. The devices must each have a 3.5mm port, at the very least. A 3.5mm port is a tiny audio jack that is typically seen on portable electronics. Although bigger sound equipment also uses this technology, its compact size makes it ideal for smaller devices.

3.5 mm Audio Cable
3.5 mm Cable

Optical Audio Cable

The main purpose of utilizing an optical audio cable is to send high-quality digital sound signals between two compatible devices. An optical audio connection is also known as a TOSLINK connection. These digital signals are transmitted through optical cables using optic fibers, where they are interpreted and decoded at the other end. 

Optical Audio Cable
Optical Audio Cable

3.5 mm vs Optical Audio Cable

“The main difference between an optical and a 3.5mm audio jack is that with optical, you send the signals digitally, and with the 3.5mm jack, the signal is sent the analog way.”

Let’s compare the characteristics and benefits of 3.5 mm and optical cable to put an end to the debate of which one possesses greater audio quality. 

Audio Formats

Not all audio formats are compatible with every audio cable. Due to bandwidth limitations, optical outputs are unable to handle high-definition audio formats as Dolby TrueHD and DTS-HD Master Audio as well as multichannel LPCM, Dolby Digital Plus, Dolby Atmos, and DTS: X. An optical cable connection will downmix the sound output into a lower quality audio signal if you try to play an incompatible audio format. However, there are certain audio formats that they do support, and they are:

  • Lossless 2.0 (stereo) PCM audio.
  • Compressed DTS Digital Surround.
  • DTS-ES Discrete 6.1
  • DTS-ES Matrix 6.1
  • Compressed Dolby Digital 2.0
  • Compressed Dolby Digital 5.1
  • Dolby Digital EX
Optical Audio Cable send the signals digitally
Optical Audio Cable send the signals digitally

Coming to the 3.5 mm audio cable, they’re great at transmitting stereo analog audio format or stereo PCM audio signals and mono sound. They don’t, however, send digital audio formats such as Dolby Digital and DTS. They’re also not compatible with stereo sound. 


As mentioned earlier, optical audio cable transfers digital audio signals, and digital audio is available in stereo or 5.1 surround sound. Along with CD players and TV to a 5.1 sound system, optical cables can be used in the following devices:

  • Cable/satellite set-top boxes
  • DVRs
  • Game consoles
  • AV Preamp
  • Home theater receivers
  • Disc Players
  • Select stereo receivers
  • Soundbars
  • Select powered wired or wireless speakers.
3.5 mm Cable  send analog audio signals
3.5 mm cable carries an analog signal

Most portable electronic devices, such as laptops, CD/DVD players, MP3 players, and cell phones, typically include a 3.5mm connector. A 3.5mm connection is also available on bigger devices like TVs, PCs, and AV receivers. There are several 3.5mm audio cable combinations, including the following:

3.5 mm to RCA- This cable also connects a device that includes a 3.5mm output port to a device with RCA input ports. Or the cable may also come with a 3.5mm plug on one end and 3 colored RCA plugs on the other end. This type of connection is used in camcorders and cameras.

RCA to 3.5mm mono– This kind of cable is used for transmitting mono sound signals.

3.5mm male to 3.5mm female- The main purpose of this kind of cable is to increase the distance between two 3.5mm cable connections.

3.5mm patch cable- This kind of cable features a 3.5mm plug on both ends and is suitable for connecting devices like an MP3 player or smartphone to a car stereo.

Cable Length

Extremely lengthy optical cable lines may restrict the effectiveness of optical cables. The optimal length for an optical cable of superior quality is 5 meters. A 10-meter optical cable is also available and does its job. However, the audio quality won’t be the same.

On the other hand, you can extend the 3 mm cable up to 30m without hampering the audio quality. The same goes for the 3.5mm patch cable. The shorter 3.5mm cables can be extended with several 3.5mm male to 3.5mm female cables.

Sound Quality

Since an optical cable utilizes light rather than electricity to transport signals, there is less signal degradation. This cable is substantially less susceptible to noise and disturbance and immune to electromagnetic interference. We can hear a loud, clear sound without any distortion. And since a 3 mm cable carries an analog signal, they’re more prone to interference. We are able to hear popping or hissing noises whenever there is any sort of distortion in the sound.

Sound Quality

Which Audio Cable is Better?

Both 3 mm and optical cable have their fair share of advantages and disadvantages. It really boils down to what kind of cable you want for your desired application,

If you want a longer cable length, then 3 mm would be a perfect choice. Because, unlike an optical cable, 3.5mm cables don’t lose data. And when it comes to a clear and distortion-free audio experience, an optical cable has the upper hand. Hence, regardless of the connection method you use, make sure to spend money on high-quality cables.

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Nafiul Haque

Nafiul Haque has grown up playing on all the major gaming platforms. And he got his start as a journalist covering all the latest gaming news, reviews, leaks, etc. As he grew as a person, he became deeply involved with gaming hardware and equipment. Now, he spends his days writing about everything from reviewing the latest gaming laptops to comparing the performance of the latest GPUs and consoles.