"Green" Reflex Tweak

This is a tweak for the few owners of the pre-release "green" Reflex who bought via the Rockgrotto offer, and applies to those phono preamps shipped before today's date (15th Jan 2008).

It requires a simple value change to a resistor in the discrete voltage regulator section. There is a bank of 5 resistors and a diode above one of the op-amps. The resistor furthest away next to the diode is currently 470R. It should be changed to 1k. It's a good idea to use a Welwyn TI MFR4 type which is the type used throughout the design. After modifying the board it is wise to check the voltage across the series zeners (located in the centre of the pcb) which should be 18.2V plus or minus 5%.

I'd detected a very slight "sizzle" on some vocals and instruments like saxophone and decided it must be an artefact of the switched-mode power supply. The tweak reduces the zener current sufficiently to curtail this subtle distortion.

If owners can't detect anything like I've described, not to worry, the unit will carry on working without this mod.

Don't worry Sol, he does it to me all the time....

Hi David,

Have noticed what seems to be a bit of distortion on a couple of old 60s tracks (repressing/reissues not originals) especially with some Saxaphone which I took to be a bit of overload in the studio does it manifest in loud parts or climaxes or is noticable in quieter passages?

To be honest I am sorting out getting a new cartridge as mine is quite old and so I have also wondered if its this. I will compare with my Gram amp 2SE.

Edited by ServerBaboon - 28 Jan 2008 at 11:23pm