How quiet is your Rogue Sphinx?

Devilboy,

Who chose your screen name here?

So an update on the humming sphinx.

I took it to the audio store and compared it to their shop floor model, both units demonstrated the same unit hum and noise from the speakers. The conclusion by the store associate was that it was a bit noisier than he expected but hadn't especially noticed though I think he had noticed the hum from the left speaker was louder than that in the right. He felt the unit hum was the transformer but was a bit perplexed by the hum from the speakers especially how the hum increased on the right side when the balance was turned all the way left!

Anyway I will assume for now that the unit is operating to spec even if it a bit noisier than ideal, I have provided Rogue with the details, although it is interesting that Rogue felt the amp should have no noise but the two units examined do give off some noise.

Only if the balance control was turned entirely left would the hum be audible over quiet music at close listening, in practice I don't use the balance anyway so it is not an issue. Overall I feel the sphinx could be quieter but for me the noise does not affect the music, it is simply not loud enough. Maybe Rogue could change something in the amp to quiet things down a bit in the future. If I had been more aware of the noise upon initial demo I might have been persuaded to try quieter models but as it stands I like the amp so its good for now.

Rpeluso.....???

Big_katydid; Transformer hum does happen with some amps and you should try to find a device like the PS Audio Humbuster (which I believe is discontinued).

As for the volume control related hum, I would send this unit to Rogue for warranty repair. This very similar hum on my preamp was the result of a faulty part. Rogue does not make the volume or balance pots, they buy a batch of ALPS pots. They may tell you to swap out the tubes and clean the contacts and other troubleshooting tips, but in the end, this is their problem.

They are a very reasonable group of guys and they want their customers to be happy with their products, so they should have no issue with servicing the unit. If it was me, I would tell them this hum was unacceptable.

Yep, don't convince yourself the speaker hum is acceptable, as your pre should never have left the manufacturer exhibiting hum. Gear is just too expensive not to work perfectly, and that means no hum.