Sound Image - G5 Loudspeaker Test Data

G5 LOUDSPEAKER TEST DATA

Sound Image G-5 Measurement comparison between Carbon Fiber Composite and Birch plywood enclosures

The two graphs represent sine wave sweeps performed with the same drive system on one of Sound Image's G-5L cored carbon 4 x 18 ” enclosures (JBL 2242H) and one of their 18 ply birch N-4L 4 x 18 ” enclosures (also equipped with JBL 2242H woofers). The test equipment (Analogue B & K system) measures sound pressure and plots the graph, in real time, on the sprocket fed data sheets (pretty cool, eh?) The N-4 enclosure is slightly larger to account for the volume that the bracing requires. The top and bottom of the N-4's are 1.5 ” birch, the baffles are 1.25 ” birch and the remaining sections are .75” thickness. The G-5L utilizes a carbon composite exterior over .75” honeycomb core and a composite interior. Each enclosure has the same internal volume and tuning and are chambered into two sections. All components were in good working order and appropriately ” broken-in ”. The G-5L graph starts to separate at 40 Hz and achieves a 2 dB advantage over the N-4L at 55 Hz. That advantage narrows to 1.5 dB at 160 Hz and meets the N-4L at about 250 Hz.