[ConGrUenCy]

Hi, I'm a first year electronics engineering student. I've taken on an extra project for myself to build a headphone amp. I'd say my basics are quite good and I'm ready to start building it (been reading a lot of theory for the past month and got help from my teachers), so I was wondering  if you guys could give me a general outline of the circuit. I'm planning on building a variable gain amp, with a switch to change the gain, so I can use it with 32ohm, 320ohms and 600ohms headphones. Right now, I might probably use some Philips audio op-amps, but I was wondering if there are any better op-amps available which aren't too expensive. 

 

[Avro_Arrow]

You should ask this question in the DIY section...

 

[ConGrUenCy]

Ah, ok, could a mod please move it to the DIY section?

 

[KnightOfAwesome]

This thread over at DIYaudio will offer some advice:
http://www.diyaudio.com/forums/solid-state/66526-there-any-better-op-than-opa2134-10.html

 

[fubar3]

 
Quote:

I've taken on an extra project for myself to build a headphone amp.

Try the Headbanger at
http://electronics-diy.com/electronic_schematic.php?id=665
 
It uses the cheap LM386 found in noisy squawk boxes everywhere. This chip has internal resistors for gain and feedback and the default gain is very high. But the headbanger designer has set the gain to 11 and minimized distortion such that the sound is very good.  The output is capacitor coupled which results in a simple circuit that won't destroy your phones.
 
It would be interesting to have a Headbanger-Cmoy sound off. May the best DIY win.

 

[Costia]

I am an EE student as well
TI just shipped me a free (to israel, including free shipping) sample of their OPA132 (2 chips)
They might send samples of the more expensive ones as well, but i felt that for my first amp i shouldn't use anything expensive or take advantage of TIs free samples offer
Try that, don't think you can get anything cheaper than for free
 
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