Friday, November 12, 2010
While doing research for Designing an Opamp headphone amplifier circuits portable, I built a portable headphone amplifier for testing purposes. EACH channel uses a single Burr-Brown Op-Amp NE5534 in a inverting configuration. It has adequate current capability to drive most headphones without an output stage. I have Used it with Sennheiser 465s and achieved ear-splitting volume. The amplifier is ideal as a booster for power-conserving stereo sources Such as portable CD players and for interfacing with passive EQ networks Such as tone controls or a headphone acoustic simulator.
The schematic for one channel of the amplifier is shown in figure below
List Component:
P1 : 22K Dual gang Log Potentiometer
R1,R5 : 18K 1/4W Resistors
R2,R3,R4,R6: 68K 1/4W Resistors
C1,C2,C6 : 4µ7/25V Electrolytic Capacitors
C3,C7 : 22pF Ceramic Capacitors
C4,C5,C8 : 220µF/25V Electrolytic Capacitors
IC1 : NE5532 Dual Op-amp
J1 : 3.5mm Stereo Jack Socket
SW1 : SPST Slide or toggle switch
B1 : 9 Volt PP3 battery
The NE5532 is a very convenient package of two 5534s in one 8-pin devices with internal unity-gain compensation, as there are no spare pins. The 5534/2 is a low-distortion, low-noise device, having also the ability to drive low-impedance loads to a full voltage swing while maintaining low distortion. Furthermore, it is fully output short-circuit proof. Therefore, this circuit was implemented with a single NE5532 chip forming a pair of stereo, inverting amplifiers, having an ac gain of about 3.5 and capable of delivering up to 3.6V peak-to-peak into a 32 Ohm load (corresponding to 50mW RMS) at less than 0.025% total harmonic distortion (1kHz & 10kHz).
Labels: Headphone Amplifier, Op-Amp Ampifier
0 Comments:
Subscribe to:
Post Comments (Atom)