OPA1622 Based amp

This is a nice sounding little chip.

http://www.ti.com/tool/opa1622evm

You need to feed it balanced input, but, its worth the effort.

Here are photos of mine. I built the enclosure. The power supply is a Rod Elliot design and provides +/- 15v to the line level driver, and the amp board. The line driver board is also a Rod Elliot design, though I had to reverse engineer it because shipping from Aus is too high for just 1 unpopulated board. The line driver uses high precision vishay resistors, and JRC 4556AD op amps. It takes the output from the ODAC or an extrrnal input and makes it balanced for the OPA1622. Its not pretty, but its mine! Would love to feed it with a Modi MB.







Here is a link to a forum post by the lead designer of the chip from diyaudio.com:

http://www.diyaudio.com/forums/vendors-bazaar/283672-new-audio-op-amp-opa1622.html

A really fun little project that I learned a lot about balanced analog signals from.

Cheers!

Ok, I can't get image links from flickr to work, sorry.

 

You'd want to enclose the actual image (JPG etc) URL in the image itself, not the URL to the image viewer in flickr, i.e. using https://c1.staticflickr.com/5/4177/34237105802_1289aec292_b.jpg instead of https://www.flickr.com/photos/154308470@N03/34237105802/in/photostream/

 

Finally learned how to get good urls from flickr.

 

Resurrecting this thread but I came across this frontend @tomchr made for the eval board that I think is pretty cool

https://neurochrome.com/products/hp-22

 

That's kind of what I was thinking. For the price of this after its all cased up I can get a Magni Heresy which also has dirt low distortion numbers

Schiit once again making most DIY useless

 

I’ve reworked this thing. I’m sure I’m biased, but running it off if 4 18650 batteries (+/- 7.4V) and an RK27 pot, I think it’s a good sized step up over the Magni 3+. I know that sounds silly, but I swear I could blind AB them with my headphones and a Modi Multibit.

Edit: no where near the power of the Magni though. Not even close.