Cockpit Coaxial Systems Cockpit coaxial systems feature coaxially mounted woofers and tweeters. The woofer in the Cockpit systems is optimized for infinite-baffle operation, without a dedicated enclosure behind it. Three sizes of M-Series Cockpit Coaxials are available. The 6.5-inch M650-CCX is ideal for tighter spaces. For an extra sonic edge and a healthy output boost, consider our unique 7.7-inch diameter M-Series coaxial speaker systems. For uncompromising mid-bass fidelity and even greater output still, the 8.8-inch coaxials are the largest diameter drivers in the line and really pack a punch.