Introduction

Presenting Pocket Amp 2 – Version 2 (PA2V2), a wonderful sounding, hi-fidelity portable headphone amplifier. This amplifier easily connects in between your source device and headphones, in order to improve the overall quality of your listening experience. Not only will the PA2V2 make your music louder, but more importantly make it rich in bass, and bring out crisp, cleaner high frequencies – just like you would hear by plugging your headphones into a powerful, full sized home stereo. It is my hope that this amp will allow you to hear and experience your favourite songs in a new and exciting way!

Build

The amp is built inside a strong ABS case and a transparent Acrylic front panel displays the quality components on the circuit board. Everything is held together with metal screws and threaded locks. It’s something you actually could take apart with tools, then put back together.

It is built to provide you with years of service, and also to be serviceable, should any parts wear out in the future. All amplifiers have a lifetime, no fault, transferable, free repair warranty.

Technical

The PA2V2 is based on the LM4881 opamp, built in a simple and classic inverting feedback circuit. It is supported by good quality parts, chosen specifically to create the resulting sound character (which many owners report to be slightly warm). Features:

• The Amp Measures 2.6″ x 2.6″ x 1.1″
• The LM4881 Operational Amplifier
• Bourns Audio Potentiometer
• 2x 470 uF Panasonic Input Capacitors
• 2x 2200 uF Panasonic Output Capacitors
• 1% Precision Metal Film Resistors
• Frequency Response from 5 Hz up to 40 KHz
• Signal to Noise Ratio (SNR) of 100 dB
• Variable Gain from 0 to 610%
• Operates on 2 AA Batteries
• 100 Hours or Greater Battery Life
• Plus A Few Other Secrets!

Batteries

The amp runs on two AA sized rechargeable NiMH 1.2 Volt batteries. The AA is one of the most common and easy to find batteries in the world. Ten years from now you’ll probably still be able to find them. A charging jack lets you plug in a USB charging cable or an AC adapter to make recharging simple. The amp has a very long battery life, in the area of 100 hours between charges during typical use. The rechargeable design reduces waste and saves you money.
How to Change the Batteries

Applications

Besides being used to improve sound quality, the amp has found itself in many other applications. You can basically use the amp anywhere there is an audio line-out or headphone jack. Some examples include:

• As a preamp between a portable player and full sized home system
• In a vehicle between a portable player and the AUX input jack
• Between a TV and a set of headphones to watch at night without disturbing others
• On airplanes or during travel to boost volume while watching movies
• To power speakers
• To power two or three pair of headphones at once for others to enjoy
• As part of an on-stage monitoring system for performers and musicians