Class A Follower Buffer?

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Per Mr. Pass' suggestion, I am requesting info on a simple Class A follower buffer using a constant current source for bias and a filtered 19V supply like the one used for the Amp Camp Amp.

My goal was to build a TEA2025B based amp for use with my Sony MDR-V700's, but the aforementioned low-power Class A arrangement was Mr. Pass idea, and he said I should ask about it, here.

Info would be appreciated--and I love building stuff.
 
...My goal was ...
...confusing.

Let's be more clear:
You want to drive Sony MDR-V700. Those are $50 DJ headphones, Z=24 Ω, nominal sensitivity is 107dB/mW which means that you need only 0.15V to achieve deafening sound pressure level of 107dB.
That excludes the need for voltage gain and the ugly TEA2025B should be best forgotten (it can be used only for very bad AM radio or as a monitor amp for practicing Morse code).
Class A buffer is all you need - one of the best you can build is DAO Follower but it deserves much better headphones than Sony MDR-V700. Optimal solution here would be mini F4 built with irf9620/irf610 or 2sk2013/2sj313, biased at 100-200mA, PSU +/-15V or some SE cl. A headphone buffer, like this one
IRF610-Class-A-Headphone-Amp-Schematic.png
or similar
 
Per Mr. Pass' suggestion, I am requesting info on a simple Class A follower buffer using a constant current source for bias ...

If you only need very low power this shouldn't be too hard to make or too expensive.

I think somebody mentioned this already:
DIY IRF610 MOSFET Class-A Headphone Amplifier Project


If you want more power you could look here too (you could use this one at lower voltage perhaps since you don't need 7W):

http://www.diyaudio.com/forums/pass-labs/66822-sewa-seven-watt-amplifier.html
 
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I built the NP-100v12 in to a little wooden box. It's pretty easy to make and sounds really good. I made it because I too wanted a tube type hpa. (Don't look to close because I definitely messed up a few things while making it).
 

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I built the NP-100v12 in to a little wooden box. It's pretty easy to make and sounds really good. I made it because I too wanted a tube type hpa. (Don't look to close because I definitely messed up a few things while making it).

Could you tell me which headphones you're using with it? I'm just wondering if they're comparable specs as the pages concerning the NP-100v12 don't actually mention which cans they are compatible with, IIRC.
 
If it happens that your music source is some gadget with extremely weak output and you still need gain, this circuit will provide some (about 2.5V/V), together with single ended cl. A buffer:

When I actually thought about your post, I considered how many devices I may have which I would like to utilize for listening purposes, and I realized that I am probably going to need this. Thank you, very much!

(For instance, my original Playstation, which I believe has very weak output. No, I won't be using this as a quality transport, but in any case, thanks!)
 
I purchased the parts to build the IRF610, just to get my feet wet (though I wanted to build the NP-100v12) and get to listening. I'm still trying to decide on an enclosure, and have to get a wall-wart to power it, plus a power-switch. I have an ancient HP oscilloscope which I've been gutting for parts that I can probably get some goods from. (and realized after I began tearing it apart that it had plenty of 12AX7's AU7's and AT7's, great for rolling in a future NP-100v12, which I had unknowingly set aside in a box!)
 
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