Induction loop for a micro earpiece: Bluetooth or jack?
A micro earpiece is only as good as the loop sending to it. Choosing between Bluetooth and a cable decides convenience, reliability and which devices the kit will work with at all.
An induction loop is a wire worn around the neck like a necklace, connected to a small electronics module. The module receives sound from the phone and passes it through the wire, which creates a magnetic field picked up by the micro earpiece. We explain the physics in How a micro earpiece works. Here we focus on the practical choice.
Bluetooth loop
The loop module works like an ordinary wireless headset. You pair it with your phone once, and after that it connects automatically when switched on. The phone can be in your pocket, bag or on the desk, as long as it is within Bluetooth range, usually a few metres.
- Pros: no cable to the phone at all, works with any smartphone (including those without a headphone socket), easy call answering with a button on the module.
- Cons: you have to remember to charge the built-in battery, a short delay when connecting is possible, susceptible to interference where there are very many radio devices.
Bluetooth loops come with or without a microphone. The version with a microphone lets you hold a normal conversation: you speak and the microphone in the module picks up your voice. The version without one only plays sound; you then speak into the phone or not at all (for example when listening to a recording).
3.5 mm jack loop
A loop connected by cable to the headphone socket. No pairing, no connecting: you plug it in and it works. It is the simplest and most predictable solution.
- Pros: zero setup, no delay, works with any device with a headphone output: phone, voice recorder, MP3 player, walkie-talkie, radio, laptop.
- Cons: the cable between the loop and the device has to be routed under your clothes; newer phones have no jack socket and need a USB-C or Lightning adapter.
Watch out for adapters
Not every USB-C to jack adapter supports a microphone. If you want to talk through a jack loop connected to a new phone, choose an adapter with an active DAC and microphone support (4-pole jack, CTIA standard).
Comparison
| Bluetooth | 3.5 mm jack | |
|---|---|---|
| Connection to phone | wireless, pairing | cable |
| Phones without a jack socket | works straight away | only with an adapter |
| Other devices | only Bluetooth ones | anything with a headphone output |
| Loop power | rechargeable battery, USB charging | depends on the model: battery or rechargeable |
| Microphone | in selected models | usually in the cable |
| Failure risk | depends on the radio link | practically none, apart from the cable |
There is also a third option: a GSM module with its own SIM card that replaces the phone. We describe it in Micro earpiece without a phone.
Neck loop or induction disc?
Besides the classic loop there are also induction discs: flat coils worn under a strap, on the shoulder or in a shirt pocket. They produce a more concentrated field, so they must be closer to the ear. They work well where a wire around the neck would be uncomfortable, but need more careful positioning.
How to wear the loop so it plays well
- Put the loop around your neck under your clothes, ideally directly over a T-shirt or on the skin.
- Let the wire hang loose and round: do not coil it or twist it into a figure of eight.
- Hide the electronics module in a shirt pocket, behind your belt or tape it in place; the cable must not be pulled tight.
- Keep the phone at least 30–50 cm from your head. A phone right next to the ear can cause buzzing.
Which one to choose?
If you have a modern smartphone and value convenience: a Bluetooth loop with a microphone. If you want to connect different devices or value reliability above all: a jack loop. Both work with the same induction micro earpieces, so you can buy or change the loop at any time without changing the earpiece.
Current loop models are available at hota.pl: induction loops and complete kits with an earpiece.