I'm not sure an upgrade to the OEM speakers is necessary to achieve better clarity and volume.
Until I started using the swimming type ear plugs, hearing the radio clearly on the super slab was very poor.
It's all the wind noise occurring around my ears that caused my problems.
The ear plugs cleared everything up.
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Absoluetly Ricky-D it's mostly that darn wind noise, I can hear the stereo better with my modular helmet jaw bar pulled down. Well I wouldn't say better sound really or louder but cutting that wind noise out sure helps my old ears hear the radio better and clearer. But then again I have been riding with an over sized windshield last winter and all 4 speakers upgraded with the Pold Audio and a 400WATT amp driving them. I can hear the stereo very well all the way up to 105-110 range after that it gets really crushed out with all the wind noise even with the stereo set at maximun volume...
Stock speakers no amp I could hear my stereo at well over 75-80Mph behind the stock windshield. (Just FYI:)
P.S. I am in the process of deciding if I will swap out my amp for a new one or just go back to the stock radio output power. I recently lost the front channel of my stereo luckily it is the fault of the amp or wiring not the actual radio itself.. verified by attaching the front speakers to the rear channel of the amp and the speakers still work and when I attach the rear speaker to the front channel of the amp then no noise, attach any speakers directly to any stereo output and all 4 channels will work. So it looks like the AMP is my fualting issue.