Supergreen Preamp born

After probably one year I finally made it:












pictures in higher resolution can be seen here: http://www.twin-x.com/groupdiy/displayimage.php?album=12&pos=22

Soundfiles with different Opamps are posted here: http://www.groupdiy.com/index.php?topic=19118&start=0&postdays=0&postorder=asc&highlight=supergreen+soundfiles

I decided to go with the OP275 behind the transistors and Signetics NE5534 at the output.

lots of thanks to Olaf, Frank, Kubi and each and everyone here for your support, shared knowledge, positive vibes and inspiration.

:guinness: :guinness: :guinness:

:thumb:

Nice Job , might as well go for the quad , Enjoy !

regards Greg

what'd you use for the PSU? is that a JLM powerstation? what power tranny did you use?

front panel looks great!

[quote author="outoftune"]what'd you use for the PSU? is that a JLM powerstation? what power tranny did you use?

front panel looks great![/quote]

230V:24V+24V for +-20V and 48V
if you use the latest Power station you could lower the secondary voltage to 18V+18V and use the tripler mode to generate the 48V rail

The Frontpaneldesign is by nregrecording ( see here: http://www.groupdiy.com/FORUm/viewtopic.php?t=10232&sid=e497663bf99ef82d46da767930a05c11 )

That has to be respected

Down some Becks after that !

Thanks to drpat who updated the mikepre thread. Seeing this thread reminded me that I did little changes to my supergreen. It turned out that the mains transformer spilled some hum into two preamps. I decided to shield it which gave me a few dB less noise.
It doesn´t look nice but it works:



As you might have seen on the second picture I did also shield the wires next to the first preampcard. This did improve noise as much as shielding the tranny. Interesting. You never stop learning.

If there's still some hum, shielding those big input caps might help.

I tried that when I was fiddling with the shielding but that made things worse! Shielding the wires did the trick.

Very nice...
I more and more come to the conclusion that green is a nice front panel color