Reddit mentions of VoiceBooster Voice Amplifier 12watts Black MR1505 (Aker) by TK Products, Portable, for Teachers, Coaches, Tour Guides, Presentations, Costumes, Etc.

I am copy-pasting the relevant portion from Help - Cosplay (from our audio recorder app which is for Android) - it relates to how to connect the earphone jack to an external microphone and external speaker - i.e. a setup suitable for cosplay (but will give you some idea of the options):

Quote:

Capabilities of the earphone jack on Android devices

The earphone jack on your device has pins for 2 channel (stereo) output, and 1 channel (mono) input. This is the case for both Android devices and iOS devices. That is, you can only have mono microphone input. This is why headsets have stereo earphones, but only one microphones (mono).

Here is a website with a good explanation of the earphone jack on your android device, and what the pins on the jack are used for (stereo out and mono in) - see the section - External microphone through the headset port.

Audio Recording With a Smartphone





Recommendations for Y-splitter cables and external speakers

For the external speaker, one with a wired connection will work, and these cost from 5 USD to 10 USD.

Y-splitters are also cheap (1 USD to 5 USD), but finding ones that actually work is more difficult (since headphone splitters look very similar, or the Y-splitter is made incorrectly).

Here is a combination of Y-splitter and external speaker that is recommended by cosplayers (the external speaker comes with a wearable directional microphone suitable for cosplay). These are costly, but known to work:



Manufacturer direct order links:

Rockit Y-splitter - Cost 11.95 USD



VoiceBooster MR1505 (Aker) 12watt Voice Amplifier - SKU: MR1505-12W - Cost 54 USD



VoiceBooster MR1506 (Aker) 10watt Voice Amplifier - SKU: MR1506-10W - Cost 48 USD




Y-splitters available on Amazon (we have not tested these)

ENVEL 3.5mm Jack Cable Adapter Kit Mutual Convertors for PC headset and Smartphone Tablet Earphone with Headphone/Microphone Function Simultaneously Y Splitter Audio 2 Female to 1 Male (Cable) - Cost 5 USD



StarTech.com Headset adapter for headsets with separate headphone / microphone plugs - 3.5mm 4 position to 2x 3 position 3.5mm M/F - Cost 7 USD

BEBONCOOL(TM) 3.5mm 4-Pin to 2x 3-Pin 3.5mm Headset Splitter Adapter M/F - Cost 6 USD



The same Aker speakers are available on Amazon:

VoiceBooster Voice Amplifier 12watts Black MR1505 (Aker) by TK Products, Portable, for Teachers, Coaches, Tour Guides, Presentations, Costumes, Etc. - Cost 64 USD



Y-splitters available on Ali Express (we have not tested these)

[Splitter Headphones jack 3.5 mm Stereo Audio Y-Splitter 2 Female 1 Male Cable Adapter with separate headphone / microphone plug - Cost 1.55 USD] (https://www.aliexpress.com/item/Free-shipping-1pcs-lot-Gold-plated-Audio-Stereo-Plug-3-5mm-1-Male-to-2-Female/32339337262.html)

Splitter Headphones 3.5 mm plug Stereo Audio Y-Splitter 2 Female 1 Male Cable Adapter with separate headphone microphone jack - Cost 3 USD



The same Aker speakers are available on Ali Express:

Aker MR1505 Waistband Portable Loud Voice Booster Amplifier Speaker VoiceBooster Amplifier 12watts for MP3 - Cost about 30 USD

Aker MR1506 Voice Amplifier 10watts Black for Teachers, Coaches, Tour Guides, Presentations, Costumes etc - Cost about 30 USD

Here are a few that come to mind:

• Boots
  
• Replacement helmet padding
  
• Helmet fans
  
• Rechargeable usb battery for fans
  
• Amp and mic system
  
• Replacement Belt
  

How would I connect a Bluetooth headset such as this to this

The application is projecting my voice from inside a helmet to a speaker on my chest. Currently I accomplish this with a AKER but it has to be wired and it interferes with removing my helmet. I am trying to make a micro wireless system without spending a lot, or adding a lot of weight.

I cannot use a netbook, has to be my smartphone (HTC ONE) as it is the only thing I can carry on my person.

I'll try to work out the App.

I am working with a [this speaker] (http://www.amazon.com/Philips-Sbt10-Bluetooth-Speaker-white/dp/B00H39NZQM/ref=sr_1_1?s=wireless&ie=UTF8&qid=1395823634&sr=1-1&keywords=sbt10), a HTC ONE android, and I have yet to settle on a bluetooth mic, but I have an off brand one lying around somewhere.