Happy_Listner said:
Hey Vlad,
I have an old Creek 4330 I'm using and it hums quite a bit. Through the casework and through the speakers I can hear it. Putting my hand on top of the Creek I can even feel it vibrate. This is one of the main reasons it's time for me to upgrade. Do you think it's because it's old? Any chance of fire or meltdown?
Anyways, I have had more than dozen amps in my system over the years, in the same location, and none of them hummed. So I guess I can't blame my mains voltage can I?
Back to the shielded mains transformer, I noticed the Marantz has one but most of the other amps do not? Or are they using the heat sink to shield it?
Vald, you know way more about this than I do, Thanks.
The 4330 has absolutely no shielding. All of the magnetic flux bombards the naked electronics increasing noise and distortion (in the Linn & Naim ethos known as PRaT and foot tapping). But I'd imagine its not that bad since the transformer is small and at a distance. However, that means less PRaT, mind you. *ROFL*
Having no transformer shielding is not the reason for the hum. It might be mains DC filth, quiescent current out of calibration, cold solder joint, the transformer windings and core just loosened up and developed a hum due to age and use.
The Creek can be easily fixed. Most likely a squirt of Deoxit and small calibration of the quescent current is all ti needs. I personally would recap, clean and re-calibrate the unit, make it as good as new for the next 20 years. You can even change the transformer if it developed a hum due to age, they are not that expensive and the 4330 has modest needs.
A massive Noratel 1000VA-1500VA transformer with custom wound secondary rails costs under 200$ delivered. I'd imagine much much less than that for a standard stock Noratel at only 350VA for the Creek 4330. You can even buy a transformer with a metal shield dome and have less noise in your sound.
To clean and adjust the quiescent current, you can do this yourself. To recap and/or change a transformer maybe best leave it to a service tehnician if you haven't fixed electronics before. Why not ask for a quote for normal service maintanance from a local tech guy?