Furman HA6AB

The HA-6AB Headphone/Monitor Amplifier is a unique combination of a headphone amp and a conventional power amp. This combination of functions can save the expense of an extra power amp in many recording studios.

The HA-6AB is basically an economical 20 watt per channel stereo amplifier. Unlike a conventional power amp, however, it has six headphone outputs (stereo phone jacks) on the front panel, each with an associated volume control. When used for overdubbing or rehearsal, this provides more than adequate loudness in all headphones (even older low-impedance models), and allows each musician to set his or her own comfortable volume level. When the overdubbing is complete and the musicians remove their headphones, the HA-6AB can power the tape playback through either (or both) of two sets of studio monitor speakers, selected by pressing front panel pushbuttons. Without the HA-6AB, a separate amp would be needed for the studio speakers.

The HA-6AB also features a convenient input level control on the left side of the front panel. A pair of yellow LED's-one for each channel-light up whenever signal is present (threshold -28 dBu). Another pair of red LED's show an overload condition in either channel.

The Furman HA-6AB's 20 watts-per-channel make it ideal as a low distortion headphone driver for the most critical listening situations. While most headphone amps provide half a watt or less per headphone channel, the HA-6AB's higher power can drive headphones of any impedance to their full rated listening level, and do so with minimal noise and distortion. Its power capacity is also just right for the small "cube" reference speakers used in most recording studios as a comparison with the main control room monitors-it can power them without overpowering them. On the studio floor, a set of small monitor speakers driven by the HA-6AB can make a session progress more efficiently by giving the musicians a chance to hear a playback without needing to disconnect themselves from their equipment and walk into the control room.

The HA-6AB utilizes an efficient toroidal power transformer for silent operation and low magnetic leakage, as required in a studio environment. It is fully protected against thermal overload, and it can withstand a short circuit on any or all outputs for an indefinite time without damage.

Features:

• Powers headphones AND speakers
• New toroidal transformer for studio-quiet operation and low magnetic leakage
• 20 watts per channel, stereo
• 6 headphone outs, each with volume control
• Switches for two sets of speakers
• Automatically switches to mono mode when right channel is not used
• Overload and signal-present LED's for each channel
• Ground lift, on-off switches; power-on indicator
• Provision for remotely located volume controls
• Standard 1/4" phone inputs
• Provides balanced inputs with XLR connectors

Specifications:

• Power: 20 watts per channel, stereo, into either 4 ohms or 8 ohms, 20 Hz to 20 KHz.
• Connectors: Speakers A: 5-way binding posts (accommodates dual banana plugs, spade lugs, bare wires, etc.) Speakers B/Remote
• Headphone: XLR
• Input Impedance: 20K ohms
• Sensitivity: -1.9 dBu (625 mV) required for full output into 8 ohms
• Connectors: Both 1/4" phone (unbalanced) and XLR (balanced)
• Distortion: .01% THD at full rated power at 1 KHz; .05% THD 20Hz to 20 KHz
• Dynamic Range: Greater than 99 dB
• Frequency Response: +0, -1 dB from 20 Hz to 20 KHz, 1 watt output
• Dynamic Headroom: 2 dB, stereo, measured with 10 ms tone burst at 1 KHz, 1% duty cycle
• Power Requirement: 120 VAC, 60 Hz, 130 watts, and 230 VAC, 50/60 Hz versions available
• Dimensions: 1.75" H x 19" W x 7.25" D
• Weight: 9 lbs (4.2 kg)
• Agency Approvals: UL listed; CUL listed; CE listed