Rivera Hammer 320 Stereo Tube Power Amp

The Rivera Hammer 320 Stereo, also known as the TBR-5, is a large all-tube stereo rack power amp from Rivera’s early high-end rack era. Paul Rivera had been modifying and designing amplifiers for professional players since the late 1960s, later working at Fender before starting Rivera as his own amplifier company in the mid-1980s.

The Hammer 320 was designed as a stand-alone power amp for rack systems, preamps and stereo guitar setups. It delivers 320 watts total, with 160 watts per side when running 6550 power tubes, and has two independent power amp sections with separate volume, Focus, Presence and output power switching. Rivera’s Focus control adjusts speaker damping, while the input level switching allows the amp to work with everything from lower-level effects units to hotter preamp and mixer outputs.

This particular early 1990s example has standard wear from 30 years of gigging but is fully functional. It comes mounted in a heavy-duty flight case. This type of gear was used by the top players of the day, like Steve Lukather, Bruce Kulick, Paul Jackson Jr., Tim May, Michael and Rudolf Schenker and Steve Miller, which gives a good indication of the type of professional rack and stage use these amps were made for.

Is it heavy? Yes. Loud? Even more yes. But it is an awesome piece of pro 90s gear that is still ready to dominate!!

SPECIFICATIONS

Model: Rivera Hammer 320 Stereo / TBR-5
Type: All-tube stereo rack power amplifier
Made in: USA
Output power: 320 watts total
Output power per side: 160 watts per channel with 6550 power tubes
Low power mode: 45 watts per channel in low setting
Triode mode power range: 70 watts down to 20 watts per channel
Power amp sections: Two independent channels, Power Amp A and Power Amp B
Tube complement: 8 power tubes, usable with 6550, 6L6 or EL34 types depending on setup
Preamp/driver tubes: 4 x 12AX7
Front controls per channel: Input Level Select, Volume, Focus, Presence
Front switching per channel: Output H/S/L switch
Input level settings: High up to +15 dB, Normal 0 dB, Low -10 dB
Focus control: Speaker damping adjustment per channel
Presence control: High harmonic gain balance per channel
Rear power class switching: Pentode/Triode selection per channel
Speaker impedance selector: 4, 8 and 16 ohms per channel
Speaker outputs: Two speaker outputs per channel
Direct outputs: One direct output per channel
Direct output level controls: Separate level control per channel
Inputs: Mono input, Channel A input and Channel B input
Cooling: Forced-air cooling with dual rear fans
Construction: Steel rack chassis with large USA-made transformers and metal jacks
Rack size: 4U
Depth: Approx. 381 mm
Weight: 30kg