Modulus-86 build thread

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Well, the Lorlin switches aren't really sealed. They are enclosed and that is about it. I work with the very old selector switches all the time that are open. No problem as the wiping action is effective with those, and then they are easily cleaned and lubricated.

-Chris
 
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Overall, the arrangement above looks reasonable. I would mount both MOD86 boards top side up. You aren't gaining anything by flipping the one on the right upside down.
Tom

Probably a long-shot, but I'm love it if you offer pairs of mirror imaged boards for your amplifiers. I'd pay extra for that to ease my OCD layout concerns.

I realize that probably won't happen, but never hurts to ask. :)
 
Mirror image? Tom goes to great pains to maximize the performance by careful layout. So you mirror-image the PCBs -- but the LM3886 won't be mirrored and neither will the op-amps. Likely an attempt at a mirror-image PCB (1) won't really be a mirror image and (2) will have worse performance because it will be different.
 
Any comments would be welcome.

Thanks !

Seriously!?? ? Buy a Firstwatt kit of parts from the Diyaudio Shoppe. Ditch those bits or sell them on. Use that case.
The resultant amp will be Decidedly better sounding no if's ands or buts .. and cost same if not less $$.
ONLY caveat being the Firstwatt amps(s) are in the 20 /25 Watt range.
So one does need 'worth owning' Speakers. Poor gear will sound poorly.. the Firstwatts will reveal inadequacies.
As always..MANY roads to nirvana.. and not surprisingly, some are better than others.
G'luck
 
Oh, nothing... Just a little protection board. :)

Regular readers of this thread will know that many have requested a little protection board to guard against DC on the output of the amp. So without further ado, I introduce the Guardian-86.

Features:
  • Mono construction.
  • No relays! All switching is done with MOSFETs for lower distortion.
  • No relay contacts to wear.
  • Adds no distortion of its own.
  • Floating photovoltaic MOSFET driver to ensure consistent good performance throughout the full swing of the output signal.
  • 5-second delay on power-up. Output disabled when supply voltage falls below 20 V.
  • Input: Molex Mega-Fit connector for easy connection to the Modulus-286 and screw terminals for the Modulus-86 and other amps.
  • Output: Screw terminals and two 4.2 mm diameter holes at 3/4" spacing for direct mounting on the speaker output terminals.
  • 2.50 x 1.75 inch footprint.

The Guardian-86 is compatible with the Modulus-86, Modulus-286, and other single-ended (i.e. not bridged or BTL) amplifiers. There'll be a separate protection board for the Modulus-686.

Tom
 

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