Conceived, designed and built specifically for large public bicycle rides. Lightweight, aerodynamic and electronically efficient so can provide hours of clean stereo sound -with a touch of bass punch-to the biking community along the varied and constantly morphing “listening chambers” constituting the ride’s course. Three prior years (2016,17,18) of riding with a system of massively over-rated Logitech Z313 internal amp 2.1 computer gaming speakers powered via a power-sucking inverter and carried by a poorly-sprung EMT conduit trailer equipped with 12 inch foam Strider wheels bore this revelation. Full 700C wheels and a lightweight sprung suspension with linear damping minimize bounce and rattle on the wonderfully-curated and meticulously preserved collection of pavement hazards unique to the Minneapolis Bike Tour.
Amp: Amplifier Board TPA3116D2 50Wx2+100W 2.1 Channel Digital Subwoofer Power X1B4 Bigger, cleaner sound (with speakers below) than even Logitech’s outrageously overrated (200 watt RMS!) big bro’ the Z623.
Power Supply: Car Rover Li-Ion 26,000 mA-hr @ 12 volts
Stereo Speakers: Alpine SPS-10c 2; 30 watts RMS, 92 dB sensitivity, silk dome tweeter, polypro woofer
Sub-Woofer:: Sound Storm SS10: 88 dB sensitivity, 32 Hz resonant freq, 69 ounce weight, operating in sealed 17 inch inside diameter spherical enclosure .
Enclosure: Marine plywood laminated and lathe-turned sub mounting ring integral to 1 inch foam core and fiberglass-epoxy inner and outer structural skins.
Music Source: Spotify playlist in offline mode on LG Nexus 5 with dual 3.5 mm connection cord to amp.
8mm spherical rod end bearing “hitch” brazed to tab clamped to frame by hub skewer 
10 inch sub-woofer in sealed 17 inch dia spherical enclosure 
Cross-tube connecting hitch arm, supsension and sphere made of glass-wrapped, foam-filled Furious cans 
complete ride-ready rig 
29’r bike bare weight 28.5 pounds 
trailer fully-equipped weight 28 pounds 
Ash core/glass-faced spring forks and 6061 AL anti-sway bar with repurposed Zefal tire pump friction damper 
Amp under-vented SST dome for rain protection