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HIFI Headphone Amplifier Circuit Diagram

HIFI Headphone Amplifier Circuit Diagram This 1-watt amplifier leads itself par excellence for usa as driver for a low impedance headphone or as output stage in a hi-fi preamplifier driving an active loudspeaker. The schematic of this amplifier consists of an opamp type LF356 and a push-pull transistor output stage. Low-pass filter R1/C2 at the input limits the slew rateof the input signal. The fixed quiescent current of 30 mA draw by the output transistors, and set by diodes D1…D4 in conjuction with emitter resistors R7 and R8, ensures very low crossover distorsion.

Feedback resitors R3 and R4 fix the gain at about 15dB. The consequent overall distortion with a 3dB bandwidth from 10 Hz to 30 Hz is only 0.1 percent.
The amplifier delivers a maxiumum powder of 1 watt into 8 ohm for an input signal of about 500 mV rms. High-impedance headphones and 4 ohm loudspeakers may also be connected withoutdetriment.
The amplifier is best build on the printed circuit boar shonw bellow. The two tra…

Audio Power Amplifier IC LM Series

Audio Power Amplifier 170W LM4651 The combination of the LM4651 driver IC and the LM4652 power MOSFET Class D power amplifier IC provides a high efficiency amplifier solution, suitable for self-powered speakers, subwoofers and quality car boosters.

The LM 4651 is a fully integrated conventional pulse width modulator (PWM) driver, containing undervoltage, short circuit, overmodulation, and thermal shutdown protection circuitry. The IC features a standby function which shuts down the pulse width modulation, minimizing supply current.

The LM 4652 is a fully integrated H-bridge Power Mosfet IC in a TO220 power package. The IC has a built in temperature sensor to alert the LM4651 when the die temperature exceeds the threshold limit.

Used together, the LM4651 and LM4652 form a simple, compact, efficient, high quality power audio amplifier solution complete with protection, normally seen only in Class AB amplifiers.

The maximum efficiency of this circuit is 85% at 125W with a standby attenua…

Subwoofer Filter Circuit Diagram

General Description        This subwoofer active filter circuit is a 24 dB octave filter with a Bessel character and cutoff frequency of 200 Hz. So, if you are interested in experimenting with audio circuits in subwoofer range, this circuit is for you. In subwoofer range, all audio frequencies below 200 Hz can be fed to a single speaker box since the human directional perception of sound diminishes at this frequency range. The normal stereo signals above 200 Hz can be fed to 2 satellite speakers. How does the subwoofer filter works: A1 and A2 buffer the signals coming from right and left channels. Opamp combinations A2/A4 and A9/A10 function as the highpass filters. The outputs are then connected to the final amplifiers of the battelite boxes. Signals from both channels are fed to A5. Opamps A6/A7 function as the lowpassfilter, A8 as the output amplifier for the subwoofer signal. The signal level can be balanced between the subwoofer and the satellite lines. The power needed for this …

Car Subwoofer Amplifier Circuit Diagram

Circuit Description:
This unit is intended to be connected to an existing car stereo amplifier, adding the often required extra “punch” to the music by driving a subwoofer. As very low frequencies are omnidirectional, a single amplifier is necessary to drive this dedicated loudspeaker. The power amplifier used is a good and cheap BTL (Bridge Tied Load) 13 pin IC made by Philips (now NXP Semiconductors) requiring a very low parts count and capable of delivering about 22W into a 4 Ohm load at the standard car battery voltage of 14.4V. The stereo signals coming from the line outputs of the car radio amplifier are mixed at the input and, after the Level Control, the signal enters the buffer IC1A and can be phase reversed by means of SW1. This control can be useful to allow the subwoofer to be in phase with the loudspeakers of the existing car radio. Then, a 12dB/octave variable frequency Low Pass filter built around IC1B, Q1 and related components follows, allowing to adjust precisely the…

Subwoofer Filter Circuit Board

Cheap car subwoofer filter circuit description:      This subwoofer filter set Suitable for use with a great car audio system. Since this circuit is designed to operate with a 12 volt DC power. But if you put it to use with a home stereo, It do not have any rules. This subwoofer circuit set is designed to has a cut off frequencies of 200 Hz. If you are not satisfied, you can change the C6, C7, C8, new, follow the table below.       The left cannel input signal is entered pass through capacitors C1, C3 are the output Signal to the original circuit. (Or rear left in the car). And the right cannel input signal is entered to C2, C4 to the original circuit. (Or rear right in the car). Two resistors R1 and R2 will be mixer audio signal the left channel and the right channel both together. Then next wire connects to C5. This capacitor is also know as the coupling capacitor to inverting input of M5218A (IC1a). The VR1 serves as a set of IC1a gain with much or less as you want.
     The output s…

LM4702 Amplifier Circuit Diagram

LM4702 general description:     The LM4702 is a high fidelity audio power amplifier driver designed for demanding consumer and pro-audio applications. Amplifier output power may be scaled by changing the supply voltage and number of output devices. The LM4702 is capable of delivering in excess of 300 watts per channel single ended into an 8 ohm load in the presence of 10% high line headroom and 20% supply regulation. The LM4702 includes thermal shut down circuitry that activates when the die temperature exceeds 150°C. The LM4702's mute function, when activated, mutes the input drive signal and forces the amplifier output to a quiescent state. The LM4702 is available in 3 grades that span a wide range of applications and performance levels. The LM4702C is targeted at high volume applications. The LM4702B includes a higher voltage rating along – LM4702A (1) (in development): with the tighter specifications. The LM4702A(1) (in ±20V to ±100V development) is the premium part with the h…

TDA7265 subwoofer circuit diagram

TDA7265 description:      The TDA7265 is class AB dual Audio Amplifier assembled in the multi watt package specially designed for high quality sounds application as Hi-Fi music centers and stereo TV sets
TDA7265 features:
Searches related to TDA7265tda7265 amplifier circuittda7265 voltagetda7265 subwoofer circuit diagramtda7265 pcb layouttda7265 equivalenttda7265 single supplytda7265 power supplytda7265 amp circuitThe TDA7265 is class AB Dual Audio Power amplifier assembled in the @ Multiwatt package, specially designed for high quality sound application as Hi-Fi

TDA2030 Audio Amplifier 1 x40W

TDA2030 general description:    Although there are a number of hybrid output modules on the market, very few of them combine compactness with reasonable price and good performance. One of these few is SGS's used in the present amplifier. The design of the amplifier is straightforward: a power op-amp followed by two output transistors. The audio signal is applied to the non-inverting input of power op-amp IC1 TDA2030 via socket K1 and capacitor C1. The supply current to the IC varies in accordance with the input signal. Consequently, there will be a similarly varying voltage drop across resistors R6, R7, R8, and R9 since these are in the supply lines to the op-amp. As long as the current is lower than about 1A, the voltage drop across the resistors will be insufficient to switch on transistors T1 and T2. This means that outputs up to 2 W into 4 ohm are provided entirely by the op-amp. Once the output current exceeds a level of 1A, the transistors are on and contribute to the power …