Based on the Ampeg® B-15NF Portaflex®
(no mid, no presence, no master)
Get sweet and lowdown with this model of the honorable ‘60s Ampeg® B-15F bass amp, complete with the Custom Design, CTS 15 inch speaker. The unique Portaflex® design consisted of the tube amp’s electronics being mounted on a chassis that “flipped over” (hence our nifty model name) to secure as part of the speaker cabinet, intended to offer the portability of a combo, without the over-heating and rattling problems associated with combo amps of the period. Ampeg® founder Everett Hull was not a fan of Rock ‘n Roll music, and thus conservatively rated this amp at 30 watts, to encourage its users to keep the volume at “sensible” levels to avoid distortion. But we think this versatile low-ender sounds just as great turned up for some throaty growl.
All-valve bass – 25W RMS , speaker 1 x 15″ custom Eminence, preamp 3 x 12AX7, rectifier 1 x 5AR4 or 5U4G, power amp 2 x 6L6GC