Monday, October 25, 2010

The Madcap A47 buffered amp

Madcap Audio

Headphone Amplifier

(Standard Edition)

Standard Features

• A47 , 2 stage opamp design.

• BB 2x OPA2111 Opamp in a Gold-Plated DIP Socket.

• Custom printed Madcap Audio PCB

• Alps RK097 Volume Control with built in ON/OFF switch

• DC Power/Charging Jack

• Penguin Peppermint enclosure

• Dimension: Aprox size with knob:(6.2 x 11.3 x 2.4 cm)

2 Stage Opamp Design

Taking the original Cmoy design into the next level, the Madcap Audio amp features the very popular A47 design. It’s a two stage opamp approach that improves current handling. There are four opamps in the A47: two for the left ear and two for the right.

So what do all these means to you?

With improved current handling, it could drive headphones and IEMs that have relatively low impedance properly. This can improve the sound quality rather than the volume. As low impedance headphones/earphones requires more current to drive them properly.

Amplifier Chip

The Madcap Audio amp comes with a pair of OPA2111 operational amplifier, one of my favorite professional audio opamps.

It is quite a jump from the standard OPA2132/OPA2134 chips. It got this crisp clear sound that doesn’t hiss a lot, so it won’t cause users to fatigue due to prolong listening.

The opamp is mounted in a gold-plated 8-pin DIP socket, allowing you to purchase other chips to alter the amp's "signature." Amplifier stability is an important concern when trying alternative opamps. A DIP socket gives you the option to try different opamps aka (Opamp rolling).

High-Quality Components

The quality of an amplifier's capacitors, resistors, and amplification chips plays a significant role in accurate sound reproduction.

- - - High quality Wima caps (input filtering caps)

- P - Panasonic E-cap (rail splitter)

- + - +/ - 1% ¼ watt resistors

Printed Circuit Board

Most Cmoy amplifiers are built on perfboard and use thin wires to transfer the audio an electrical signals.

Madcap Audio amp is built on a high-quality printed PCB board. Which prove to be consistence and reliable when in operation.

Volume Control

The Madcap Audio Amp features the very popular Alps RK097

potentiometer, paired with a high quality brushed aluminum knob.

Power source

Unit can be powered by a standard PP3 9v battery.

The Madcap Audio amp uses A standard resistor divider power system, with a pair of low ESR panasonic 470 uF capacitors. This will allow users to use higher current rated opamps without the limitation of a limited current supply.

DC Power / Charging Jack

Any linear-regulated 12V DC power adapter with a 2.1mm plug can be used to power the Madcap Audio Amplifier. Plugging in a DC power supply in “on” position will power up the device in playback mode. Plugging in a DC power supply in “off” position set the device in trickle charging mode.

(While using the charging mode, make sure only uses a PP3 9v NiMh battery !)


The Madcap Audio Amp is cased inside of very attractive * Penguin Peppermint tin. The metal casing also acts as a protecting the circuit from some forms of external EMI / RF interference. Foam support keeps the battery securely in place.

*Despite each tin being brand new, penguin peppermint tins occasionally have some sort of scratch or dent (not always!). Additionally, you should anticipate minor jack mounting imperfections due to the hand built nature of the product. Please excuse these possible minor cosmetic defects. Thank you!


• New Madcap Audio Headphone Amplifier
• Quick Instructions Sheet