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So my work mate built a low distortion amp...

FireLion

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My work mate built an amp, he has been working on audio products all his life and now it's a hobby. I am going to start learning electronics and hopefully start building my own some day.
The two green guys are like reverse engineered gain blocks turned into an opamp of sorts which is connected by 6 large gold pins to the main PCB. The design come out of an exercise to build the ultimate low noise low distortion gain block and subject of a research paper presented at an Audio Engineering Society. The sound is pretty amazing and I was A-B'ing with a Burson Lycan with two V6 singles and this amp shown here in the picture was vastly superior in terms of dynamics, tonality and had a very black background with little to no noise.
I should have an enclosure for it soon and might get a Khadas tone board to go along with it and will update once it's complete. I just thought I's share his handy work as it was very unique and is almost as good or equal to a THX 788 I recently had but would have to A-B it's that close. My source was an AK4490 DAC from an xDuoo TA-10.
In terms of power he had seen the specs for an NFB.11 and said power is pretty close to that so that is well over 2 watts @ 32 ohms. It's also powered by a NOS 20w US Robotics power supply. It is very simple looking overall but there is a lot going on with those two green guys. I was also running a pretty much stock T50RP with ZMF pads and it sounded great, EMU Teak was pretty amazing on it too.

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FireLion

FireLion

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Just an update the SE on this is superior to an LCX, so much more crisp and no bloated bass, just need an enclosure. These may be for sale at some point on limited runs, won't be cheap as that green guy is a totally one of a kind opamp which based on an older architecture pin layout using parts meant for another purpose. I'd be happy to send one for a review once it's sealed up and it's approved by it's maker..
 
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FireLion

FireLion

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Does he have any measurements for it?

Would have to find out. He came up with this new design 2520 and applied it to his base pcb, then he has many variants of this pcb like with regular opamps etc. He makes the green 2520 by hand and his pcb fits in a regular hammond enclosure. He has a thing for this form factor but does like some of the regular opamps.

He even made a modified whammy which takes this large 5 pin 2520 opamp. Here is a few examples of his work, pretty knowledgeable guy.

WP_20170514_10_44_13_Pro.jpgDSELF_PIC.jpgPIC_02.jpgPIC_00.jpgEvhU6Ig.jpg
 
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FireLion

FireLion

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Not surprising :)

In fact it's cleaner than the balanced, I am also ABX'ing it with an xDuoo TA-10 and the tube amp is cleaner with a nice NOS tube. All I get on the LXC is muddy mid bass, very disappointing for a $380 unit.
 
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