Having seen reports of humming trannies
Mechanical vibrating noise from the transformer itself.
All transformers hum to some degree.
What the seller describes in his reply has nothing to do with transformer mechanical humming noise.
Also I would add what the seller describes in his response would be normal in many audio systems if the sound he is hearing is actually white noise and not humming.
Try his test on your existing audio system......
Email the seller back and explain to him what you want to know is if he can hear the power transformer humming with his ears, say, 3 ft from the amp.
Also ask him about his test.... Was the sound he was describing, with the volume cranked up all the way, hum or white noise?
"With the speakers connected to the 302B, I can hear a very faint hum from the speakers, but you have to put your ear right against the speaker grill to hear the hum. Turning the volume knob on the 302B has no effect on the amount of hum - the sound level remains constant regardless of the volume setting. Again, I must stress that the volume of hum is so slight, I doubt if anyone in a silent room will notice it, even when standing close to it.
Now, with a CD player hooked up to the Jolida, the hum level increases as you increase the volume on 302B. When the volume dial is turned down to minimum, the level of hum is very faint (same level as if cd player was not connected).
When the volume is turned to MAXIMUM, the hum becomes noticeable as you approach the speaker (about 3 feet away). In addition, when the CD player is on, and the input selector on the 302B is set to other than CD (such as AUX), turning the volume knob has no bearing on the hum level - it stays constant at the barely audible level.
Just bet the seller is confusing white noise with hum.....
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