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View Full Version : mesa tremoverb tremolo mod


jeff
09-05-2006, 03:58 PM
The amp uses a 555 timer base trem ckt. I would really like to get more depth out of the tremolo. I checked out the schem http://www.freeinfosociety.com/electronics/schemview.php?id=297
and the ckt is very simple. Any suggestions? Thanks

Mark Black
09-08-2006, 07:20 PM
It looks like LDR21 is the controlling factor - you might research the part number they used and perhaps come up with a different LDR with lower "ON" resistance. Then again you don't want much lower "OFF" resistance or it will load the signal.

The 10K resistor in series with the Depth control might be another place to play around - maybe try another 10K across it (for 5K resultant) to give more drive to the LED in LDR21.

You might need to pay some attention to the specifications of the LDR and associated LFO circuitry to make sure you don't exceed current maximums...

Good luck!

AdmiralB
11-25-2007, 02:05 AM
I realize this is an ancient thread, but I had the same problem. Replacing the weirdo trem LDR with a Vactrol VTL5C1 did the trick, lots more depth available.