Soundbaron
Member
- Joined
- Aug 19, 2025
- Messages
- 30
- Thread Author
- #1
I'm embarrassed to say I've never heard of, or a least never paid attention to anything called a DC blocker. I have an amp with a fairly large toroidal transformer that I noticed buzzing one day. This can't be good I thought, so I started to look for the cause and quickly noted that thankfully it wasn't coming through the speakers, but from the amp itself. It was the transformer making the noise mechanically which would be noticeable sometimes and not at all other times. Not wanting to pack up the amp because it's heavy, or ship it away because it's expensive, I decided to do a little AI research on how to cure the problem. I really didn't have high hopes of finding a solution, but much to my surprise I found one......or AI did, credit where credit is due.
Anyway, apparently larger transformers are prone to mechanical buzzing due to small amounts of DC in the AC current. I've never heard of such a thing before, and assumed maybe it was part of the why people buy power conditioners. What I found is a little device called a DC blocker which plugs into the power receptacle in the back of your amp and then which you plug your power cord into. It actually works beautifully, and I can hear virtually nothing in the way of buzzing now. The device I bought was around $149.00 and very compact. There was only one company I could find that makes them called ifi "silent power" and the product name is DC Blocker + intended for larger amps, and they have a second for smaller amps for about $100.00, but which is the same physical size and look which is kind of nice.
Yeah, as I mentioned, it actually works, which in my life's experience things rarely do. So long story shorter if you have the same issue, here's the likely cure, at least if it's caused by DC voltage in your AC.
Anyway, apparently larger transformers are prone to mechanical buzzing due to small amounts of DC in the AC current. I've never heard of such a thing before, and assumed maybe it was part of the why people buy power conditioners. What I found is a little device called a DC blocker which plugs into the power receptacle in the back of your amp and then which you plug your power cord into. It actually works beautifully, and I can hear virtually nothing in the way of buzzing now. The device I bought was around $149.00 and very compact. There was only one company I could find that makes them called ifi "silent power" and the product name is DC Blocker + intended for larger amps, and they have a second for smaller amps for about $100.00, but which is the same physical size and look which is kind of nice.
Yeah, as I mentioned, it actually works, which in my life's experience things rarely do. So long story shorter if you have the same issue, here's the likely cure, at least if it's caused by DC voltage in your AC.