Check the listing for details. Synergy SYN-20IR 20-watt Amplifier Head - No Module Included. Condition: Very Good - Refurbished. Listed at 989.99 USD. All-tube Design with Modeler Flexibility Reap the rewards of responsive tube tone structures without sacrificing innovative digital modeler sensibility with the Synergy SYN-20IR. This unique head uses the same preamp docking technology found in Synergy’s other units, with one major exception — the tubes. Sporting a portable lunchbox head design, the SYN-20IR is loaded with dual EL84 power amp tubes that, coupled with a Synergy preamp module, create a 20-watt all-tube amplifier equally at home in the studio or on the road. The flexible tonal capabilities aim to create an analog modeling system loved by Sweetwater guitarists looking to sculpt their tone with the flexibility of modern digital rigs and raw tube tone.