| svokke |
I would like to make an headphone amplifier to use at my computer. I've drawn a very simple schematic. It's an opamp stage with an emittor follower biased at 150mA with an LM317 current source. I still have to work out the resistor values. What do you think about this topology? Try it or scrap the idea
:smash: |
|
|
| v-bro |
| I used TBA820M, sounds great! And doesn't cost much.... |
|
|
| lineup |
| quote: | Originally posted by svokke
I would like to make an headphone amplifier to use at my computer. I've drawn a very simple schematic. It's an opamp stage with an emittor follower biased at 150mA with an LM317 current source. I still have to work out the resistor values. What do you think about this topology? Try it or scrap the idea
:smash: |
What gain do you need?
If your headphones are 300-600 Ohm impedance, you might need a voltage gain of 4-8.
If you will use headphones 16-100 Ohm, then you can do well with Gain 2-5.
This is if driven from CD output most of the time.
If you have other sources with lower voltage output you will use
then you should multiply those gain figures with some number.
* The nominal CD output standard is MAX 2.0V RMS,
but most CD recordings have an average level of like 0.5-0.7V RMS. |
|
|
| svokke |
| I was going to take 10k for R10 and 1K for R9. Then reduce the gain to as much as I need by increasing R9. Calculating gains, resistors, bias, etc... is not really a problem. Problem is figuring out which circuits have the best sound. |
|
|
|