A few days ago I decided to learn how the new Melq sound and made a quick speaker level crossover for one of my Macondo’s channels, putting the new built Melquiades to drive the acoustic systems that the SET meant to drive (Before it was 82dB and 88dB sensitive speakers). To my surprise it did not sound good. The sound was “large” but not delicate, detailed but not minute, colorful but not tonal. Even bass was lager and “puffier” but not as articulate as I would like to. Furthermore it little puzzled me the frequency sweeps that I have posted above was not as interesting as in the first Melquiades.
I was wondering what it might be. There are a number of minor differences between this new Melq and the original about none of them should crate problems, but in contrary be better. I really did not know….
I hypnotistsised that the only REAL difference between the old and new Melq was that the new one I decided to drive this new Melq fool force, burning the 6C33C at 60W. Since I am limited with the current on transformer I jack up voltage and run the output stage at 230V-240V. Theoretically the exercise power should truncate the frequency range but how could I confirms it and drop the voltage in output stage?
I was trying to put a larger R22 resistor, burring voltage but it increase the impedance of power supply and was not good. Then I trued to put another 40V transformer in out of phase with the B+ transformer. It dropped the voltage but did not sound well as well. Well, I took a rheostat and drove the B+ transformer with lover voltage then I have in mains. Actually the result was stunning. Ass soon I was entering domain of 105V I was getting sub 200V on plate and the sound completely changed. It was like coming back home: I lowered the voltage, wait for a few seconds until the tube cool down and then suddenly the sound begun opening up and blossom with the dazzling fertility and richness of the original Melquiades. Surprise, surprise… now the 6C33C was driven at 40W… exactly like the original Melq...
Now, I am in trouble as the B+ transformer is mounted and connected. I need now another transformer with 80V less voltage. I thought it was it but apparently it was not…
Romy the Cat
"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche