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RAAL-requisite PDA-1a Headphone Amplifier

RAAL-requisite’s all new standalone headphone amp the PDA-1a incorporates technology from the ground breaking HSA-1b for an all new amp for traditional non-electrostatic headphones. This top of the line amp delivers uncompromising performance for planar magnetic and dynamic headphones!

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A great listen, every listen, with all that you'd expect form RAAL-requisite!

Our Take

The PDA-1a by RAAL-requisite is a direct beneficiary of technology developed and derived from the highly successful and greatly reviewed HSA-1b. By eliminating the high-current requirements of speakers and ribbon headphones the model HSA has been purpose-tuned, to new heights, for even the most difficult to drive Planar and Dynamic headphones.

As a result, the PDA-1a easily drives two headphones simultaneously and provides the second headphone output with 0dB, -5dB and -10dB range attenuation for better matching when using different headphone types or to lower volume, if desired, for the second listener. Single-Ended RCA and Balanced XLR Inputs, 4-Grounding positions and 3-Levels of Input-Sensitivity, for XLR Inputs, providing for maximum range of settings for the 24-step attenuator.

What's Included

• PDA-1a

• IEC C13 Power Cable

• 5 year Manufacture Warranty

Inputs and Outputs

• Load Impedance: 0.3 ohm – infinity on headphone output connectors

• INPUT 1- 2 RCA Single-Ended

• INPUT 2 - 2 XLR 3-pin Balanced (female)

• 2 x XLR 4-pin female (balanced Planar & Dynamic headphone out)

• 2 x 6.3mm stereo jack (single ended Planar & Dynamic headphone out) for 20 - 600Ω

• Input Impedance: 40k Ω

• Sensitivity: 0.5V /40k Ω

• Working voltage: 115V/230VAC (selector switch) or 100V (requires internal connection)


Load Impedance
.03 ohm - infinity

Output Power (one channel driven)
8-ohm 12W, 16-ohm 6W, 32-ohm 3W, 64-ohm 1.5W, 120-ohm 0.75W, 240-ohm 0.35W

Freq Response
100mv/ in/sin 15hz-500kHz

Power Bandwidth
100kHz (-3dB) at 1khz

< 0,5% at 1khz

Signal to Noise Ratio
Better than 90dB

Max Power Consumption
150W, without signal 25W

H3.54" x W8.58" x D12.6"

11.7 lbs

HSA-1B & SR1a

About RAAL-requisite

RAAL-requisite represents two legendary brands in ultra high-end audio, coming together, to create a sound unlike anything the world has ever heard before.