Here's a video of me giving the 4x4 it's monthly checkup at the pond site we're digging. With good speakers or headphones, you can get a pretty good idea of what the Dynomax sounds like at low RPM.
<embed width="600" height="361" type="application/x-shockwave-flash" allowFullscreen="true" allowNetworking="all" wmode="transparent" src="http://static.photobucket.com/player.swf" flashvars="file=http%3A%2F%2Fvid1192.photobucket.com%2Falbums%2Faa332%2Fhughdarnley%2FSport%2520Trac%2FExhaustClimb.mp4">
<embed width="600" height="361" type="application/x-shockwave-flash" allowFullscreen="true" allowNetworking="all" wmode="transparent" src="http://static.photobucket.com/player.swf" flashvars="file=http%3A%2F%2Fvid1192.photobucket.com%2Falbums%2Faa332%2Fhughdarnley%2FSport%2520Trac%2FExhaustClimb.mp4">