Halo A51 transformer hum...Need power conditioner?


I recently purchased the Parasound Halo A51, and I am getting a hum from the transformer. The hum comes directly from the A51 unit and not through the speaker (it's not a ground loop problem). I send the A51 back to Parasound for repair and they replaced the transformer.

I just got the A51 back today, and the hum was reduced to a barely audible buzz. However, when I started using the microwave, the hum came back again. The hum disappeared when the microwave turned off. I live in a 30+ years old house, and so I think the power going to the A51 may not be clean.

I don't want to spend too much money on a power conditioner...maybe $200 or so. What kind of power conditioner will solve this A51 transformer hum? The PS Audio has a product called Humbuster AC. Would this Humbuster help me or do I need some other product?Below is a link to PS Audio website:

Thanks in advance for everyone's suggestions.

You should consider running a dedicated grounded circuit to your audio system.
Hi, the problem may be transformer itself, many transformers start to hum when they get older.
A DC filter may be what is required. The inductance of the trani is a short to even tiny amounts of DC voltage on the line side, and it causes the trani to hum, because the low DC impedance will cause a large DC current. There are plenty of DC blocking filters available. Search this website for info on DC filters, info galore.

As the noise is mechanical in nature, ie not in the speakers, this is the most likely cause.