Preamp Deal of the Century


If anyone is looking for a true "World Class" preamp at a very fair price..heed my advice. I just recieved a Supratek Syrah preamp that was hand built by Mick Maloney in Western Australia, and it is absolutely beautiful! This preamp is the best deal you will ever find. I would put it up against any preamp out there for both looks and sound. Price? $2500 for the Syrah (includes Killer Phono stage). Not into phono? Try the Chardonney line stage for $2100. Don't get me wrong, I am not associated with this company. I am just a very happy owner! This preamp is VERY dynamic, yet liquid. It conveys the sound of music better than any other preamp that I have ever heard! You can check out the Supratek website at www. cantech.net.au
slowhand
Swampwalker, I understand that the buzz only happened after the Joule returned from repair, and I also assume from your answer to Bwhite that the Supratek does not do this with other amps, e.g. the Berning.

If part of a circuitry has a weak ground--for example, the return (ground) connection on an interconnect or RCA socket--then this can cause the signal to "find ground"--i.e., induce a current over dielectrics--in other parts and induce buzzing in tranformers.

Once the Joule and Supratek are connected via interconencts they are essentially a single circuit--and you are getting noise in both power supplies.

My guess--and this is simply a guess--is that either the process of connecting and disconnecting interconnects has created an intermitant short in one of them, or shipping may have caused some minor weakness in one of the many internal ground paths in the Joule. Because every component is different, it is coincidential that connecting the Yamaha C2A "curcuitry" doesn't induce errant current flows, but connecting the Supratek's does.

Try: 1) swapping a few interconnects; 2) inspecting, flexing, and testing them for continuity with a voltmeter; and/or 3) opening the Joule and looking for weak solder joint.
Current situation- I have traced the noise to the torodial power transformer on the Supratek power supply. I tested the rectifiers (about 6) that I have and unless every one is bad, my tube tester is on the blink. Anyways, it starts immediately when the power switch trips the circuit. Any thoughts?
Most torroidal transformers have electrostatic screen. Besides, it is unlikely that DC will be present at the secondary. I would suspect that it is possible one of the rectifer is bad.

If you have a scope, you can look at the ripple voltage after the filter caps or at the regulator input to each channel. Most of the time it should be small (in order of millivolts). But if you measure around 100 mV or more, that could be the problem.

Just my thoughts.....
Brian, the noise was a mechanical hum from the transformer in the power supply of my Supratek. Rather loud. Now there is just a faint hum that you can hear if you put your ear near the hole in the top of the power supply.

Before I could easily hear the transformer humming from my listening chair. And BTW, the AC Offset Killer didn't seem to affect the dynamics at all, nor did it seem to add any coloration.

I used solution B.