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For Sale Monte Generoso Mic PreAmp PCB Set

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Samuel Groner

Well-known member
Aug 19, 2004
Zürich, Switzerland
Hi all,

Years back, I've designed and partially built the transformerless mic preamp "Monte Generoso". For details of the design, please see the according section on my website: www.nanovolt.ch/resources/microphone_preamplifiers/. I've never got around actually finishing the project, and by now I have no use for it anymore as I'm no longer into recording. By selling I hope that the preamp finds good use elsewhere.

The set includes:
  • one finished and tested preamp;
  • PCBs for another preamp channel and a suitable linear power supply;
  • Elma gold-plated 24 position rotary switches;
  • gold-plated switches for phantom power and polarity;
  • Haufe custom-made power transformer with Mu-metal magnetic shield;
  • three OPA627 opamps (you'll need to get a fourth one);
  • a few capacitors and a common-mode choke;
  • a partially drilled cased with custom front-panel, line voltage selector switch, and power switch;
  • printed schematics and overlay prints.
Some pictures:




The assembled channel was fully tested and working when I've built it. Unfortunately, I don't have access to a lab where I could re-test it, but as it has not been used since then I'm not expecting any issues. To build the second channel, you'll need to get an OPA627 and two MAT-02 (or equivalent). All other parts should be easy to source.

I'm estimating an equivalent current value of CHF 900.- (at the current exchange rate, roughly the same number in USD or EUR) for everything together when bought new. Please contact me by e-mail (www.nanovolt.ch/about_me/, no PMs please, thanks) with an offer. Shipping is from Switzerland.

Still available--just to make clear: I'm not looking to make a profit from selling this, just glad if it's not collecting dust anymore. So please feel free to contact me with an offer reflecting what it's worth to you.
I do not need it, but I can attest, that this is a very high end preamplifier. Years ago I did build one and it is still my favorite pre for delicate and quite signals…
Thank you for the praise. Indeed I believe it is a quite nice design and I'm surprised that there's no interest; perhaps I've just been too long away from this board. Again to make sure: Please just offer what it's worth to you.
I doubt it's a matter of lack of interest. I imagine there are numerous folks who, like me, would love to pick it up, but just don't have the cash on hand. If I did, or even if I thought I could make you a reasonable offer, I would have already jumped on this. I wish you great luck with the sale!
Perhaps I should be more specific with what I mean by "reasonable": I know I'll sell at a loss; half of the original cost (so CHF 450.-) would be great, but one third (so CHF 300.-) is OK too.
Thanks for your website. It is simple but has many good links to D.I.Y. and analog resources.

Did you ever find a buyer?

@okgb my apologies but I only saw your reply now as I'm not visiting this forum frequently anymore, and as I didn't get a notification. Did you try sending me an e-mail? I'm not aware that there are any issues with the address on my website.

@velo thanks, glad the website is of use.