FiiO LL-3.5A Launches as Boom Mic Cable for Headphones

FiiO LL-3.5A was officially launched today (June 22) in mainland China. Designed for use with over-ear headphones, the LL-3.5A cable features an oxygen-free copper (OFC) conductor and an integrated omnidirectional boom microphone. It uses 3.5 mm TS connectors and is compatible with selected headphone models from FiiO, HiFiMAN, Aune, and Meze. Check out all the details about this new release and turn your headphones into a headset.

Update (June 23): The FiiO LL-3.5A is now available from FiiO’s official store on AliExpress.

LL-3.5A delivers the essentials with quality and an affordable price

Priced at 99 yuan (approximately US$14.62), the FiiO LL-3.5A boom microphone cable for over-ear headphones stands out for the following features:

• Silver-plated OFC (oxygen-free copper) conductors
• An omnidirectional boom microphone positioned near the mouth
• An extension cable included in the box to separate the headphone and microphone connections when connecting to a desktop PC sound card

In addition to the points mentioned above, the promotional images of the cable show that it is covered with a braided fabric sleeve. According to the manufacturer, the conductors are coated with TPE (thermoplastic elastomer), an elastic and flexible material.

Compatibility with the FiiO LL-3.5A

According to the manufacturer, some headphones from both FiiO and other brands are compatible with the FiiO LL-3.5A. However, the company did not specify which models are actually supported. This is problematic, as there are several factors that may prevent the cable from working properly with certain over-ear headphones.

The LL-3.5A uses a pair of 3.5 mm TS connectors to connect to the ear cups of the over-ear headphone. For connection to a smartphone or notebook, however, the LL-3.5A uses a 3.5 mm TRRS connector.

Basically, the difference between TS and TRRS lies in the number of poles, which can be identified by the number of rings on the connector. A TS connector has only one ring, while a TRRS connector has three rings.

Even if the manufacturer specifies that the removable cable system uses dual 3.5 mm TS connectors, you may still run into problems if:

• The shape of the 3.5 mm TS plug barrel prevents proper insertion into the headphone ear cups.
• The internal soldering of the wires in the 3.5 mm TRRS plug differs from what the headphone expects.

It is possible to identify models that are more likely to be compatible with the FiiO LL-3.5A, including some that use 3.5 mm TRS connections on the ear cups. Compatibility between 3.5 mm TS cables and headphones with 3.5 mm TRS connectors is possible when one of the three contacts on the TRS connector is not used.

Table of over-ear headphones compatible with the FiiO LL-3.5A

To make it easier to choose over-ear headphone models compatible with the FiiO LL-3.5A cable, a list in table format has been created. See below.

Attention: The models listed are those that use dual 3.5 mm connectors and are not necessarily based on 3.5 mm TS (mono) connections. Due to differences in plug shape and wiring to the 3.5 mm TRRS connector, the FiiO LL-3.5A may not be compatible with some of the over-ear headphones mentioned.

Note: The list above provides only examples and does not represent all models potentially compatible with the FiiO LL-3.5A.

FiiO LL-3.5A: Specifications

• Cable color: black
• Cable length: 1.5 m (main cable) + 0.6 m (extension cable)
• Conductor: silver-plated OFC copper
• Connector for the audio device: 3.5 mm TRRS (main cable) and 2x 3.5 mm TRS + 1x female TRRS (extension cable)
• Connector for the headphones: 3.5 mm TS with a dedicated microphone connector
• Jacket material (outer covering): TPE + braided fabric sleeve
• Microphone: omnidirectional boom microphone with high-density windscreen foam

Release date, price, and availability

The FiiO LL-3.5A is now available internationally for US$20.63 from FiiO’s official store on AliExpress.