RCA to Headphone Out circuit

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Suraj143

Active Member

• Nov 9, 2011

• #1

I need to make a converter which will convert RCA out (L & R) to stereo headphone in.

Those are the specs

Line Out
=========
connectors = RCA unbalanced
output impedance = approx 400 ohms
max output level = 2dBV

Headphone
=========
Frequency response = 20 Hz - 20 kHz
Max. power handling = 100 mW
Impedance = 32 Ohm
Sensitivity = 105 dB @ 1 kHz

 

audioguru

Well-Known Member

Most Helpful Member

• Nov 9, 2011

• #2

First you must select an amplifier IC that can drive an impedance as low as 32 ohms. Two are needed for stereo. Some manufacturers make stereo headphones amplifier ICs.
Then you must select how much bass boost you need and at what frequency is the peak.
Then select a bass boost circuit and make it feed the stereo amp.

 

S

Suraj143

Active Member

• Nov 9, 2011

• #3

Hi auduio thanks

I'm going to use LM386 circuit.I don't know how many bass I need,but I need lot of bass.

Can you adjust the below circuit to my specs.specially the impedance stuff

Thanks

 

Attachments

• Headphone amp.gif

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audioguru

Well-Known Member

Most Helpful Member

• Nov 9, 2011

• #4

The circuit you found will work well.
Impedances are never matched since a signal source is usually a low impedance and an amplifier has an input with a high impedance so that some signal does not get thrown away.

 

S

Suraj143

Active Member

• Nov 9, 2011

• #5

Hi thanks audio.I'm going to build that one.Does it have more bass?

 

audioguru

Well-Known Member

Most Helpful Member

• Nov 9, 2011

• #6

The circuit you found does not have bass boost. Bass boost is shown in the datasheet of the LM386 where the values of C2 and C6 are much less.