Hy! Here are some things you may need to know before i begin. I'm a complete and utter noob in audio and i only have experience in basic electronics. Like soldering, wire cutting, reading a basic schematic, etc.
The idea of building a DIY amp came to me after i upgraded my PC. On my old one i could easily enjoy a movie without hearing anything around me. On the new one I can literally hear a fly buzzing around me at full volume...
I'm not an audiophile in the true meaning of the word, i just need some extra boost on my headphones.
I have a pair of Philips SHP1900/10 http://www.p4c.philips.com/cgi-bin/dcbint/cpindex.pl?slg=en&scy=it&ctn=SHP1900/10 that i love and worked great on my old PC. I know that the headphones are rubbish but they serve me well. And i know that they aren't broken because they work perfectly on my laptop. Also i know that the problem isn't software related because i tried all the drivers out there and all the players possible.
Sooooooo back to the amp idea. I started to look for a complete amp but all of them were really expensive. I live in Romania where the average salary per month is only around 350$ and i only make about 300$ per month. So a 100$ amp is out of discussion. I started looking at cmoy which would cost me around 10 to 20$ depending on the opamp i choose. But all of them were battery powered and i don't want that. I found the crystal cmoy on instructables which was powered by a switching power supply but it didn't have a volume control. I found the JDS Labs CmoyBB but it was also powered by a battery and it has really small caps and i understand that small caps mean poor sound quality (At least that is what i read here: http://tangentsoft.net/audio/cmoy-tutorial/parts.html#req see this annotation below: "* These caps are much bigger than the ones in the photos on subsequent pages, and so aren’t great choices for amps in mint tins and other compact enclosures. In exchange for the bulk, you get better sound. The farther down the list of alternatives you go, the worse the sound gets, with the last ones still being okay, but recommended only when space is at a premium."). Then after a little digging i found out that most Cmoys have a virtual ground (BTW i also don't know what that means) and that virtual grounds have a poor sound quality also.
Now with the part that i need help with.
I want a cmoy headphone amp with:
- an active ground
- volume knob with an on/off switch in it
- an integrated power supply so i can power it from a 10 - 15 V power supply that i have around the house (just like the crystal cmoy on instructables)
- power LED
- size does not matter. if big caps are the best option than by all means i want them. I will be running it on my desk.
- cheap build. The cheapest, the better.
And after reading a little more on the subject (this post in perticular: http://www.head-fi.org/t/243642/best-sounding-cheep-op-amp-for-cmoys-opa2227-opa2228-ad8066-other#post_3032335 by majkel) i would like it to be built around the AD825 opamp which i read that is the best sounding amp around. But because it's a SMD amp i am open to any suggestions for an alternative 8 pin dip amp that is just as good but not too pricey. I had a look at the AD797 but it's way to pricey. If anyone could lend a hand with a schematic and a parts list i would be so happy! Thanks to everyone that took the time to read my post and know that i appreciate the time and effort! Hope to hear from somebody soon and thank you in advance for the helping hand. I really appreciate it!
Edited by adrianf88 - 11/6/13 at 1:33am