http://https://www.amazon.com/iASUS-XSound-Definition-Helmet-Speakers/dp/B00MV2ZLHC/ref=sr_1_1?ie=UTF8&qid=1485491724&sr=8-1&keywords=iasus+xsound+3

Guys and Gals im happy to report my audio nirvana with the Iasus x 3 helmet speakers. Fantastic sound for $120 bucks. I was really looking at a amp and speaker upgrade but im one of those always a helmet guys. No matter how great a speaker / amp set up im always going to hear it thru a helmet. This set with a sena 20s sounds really good in my neotec helmet.
Only criticism is iasus design calls for a right side source connection for their throat mic system so the left and right are set reverse meaning out of phase . I don't care cause it sounds great. Base, treble and the speakers are of such size that placement in the shoei holes are fine. Its supplied with spacers and connects to the earbud outs on the sena 20 s. Plenty loud for me but not as loud and tinny as the sena stockers. But i love them. Thought id pass on a winner.