Details of the Gretsch 6157 Super Bass piggyback tube amplifier. The Super Bass was a 2x12" 70 watt bass amplifier with a 1968 US list price of $350. It was described as follows:
Who else but Gretsch could develop a bass amplifier so rugged that it can reproduce low frequencies at full power without damage to its specially designed speakers. Its twin speaker enclosure is separate from the piggyback amplifier chassis unit. The enclosure incorporates hi-fi principles with special attention to baffling and tuned re-sonance. This gives you clean "live" sound the way you want it, virtually distortion-free. For the ultimate in electric bass amplification here's the amp with the big power output that really puts out... sound that really reaches... the Gretsch Super Bass Piggy-back.
$4500
$1399
$1095
$399
$2195
$1495
$1550
$59
$1175
$60
$2195
$1500
$3900
$700
£4250
£1795