M2/preamp buzz

belgianbrain

Super Member
Slight buzz coming from M2.

I have a Yamaha M2 that was completely rebuilt and recapped recently (22,000 uF PS caps included).

I have a passive preamp that I built myself from a kit (high end stuff - cost me $700 to build). Essentially this thing is just a bunch of relays and resistors to select a source and attenuate as desired.

The M2 is dead silent with no preamp attached. The preamp is dead silent with no AMP attached (I have hooked up headphones to check the outputs).

Once I connect the two, I always have a very low volume buzz coming from the midrange driver on my NS-1000s. It's sometimes hard to hear, but when you put your ear near it, it's usually there and sometimes gets a bit louder so it's noticeable a few feet away.

Any ideas?
 
Slight buzz coming from M2.

I have a Yamaha M2 that was completely rebuilt and recapped recently (22,000 uF PS caps included).

I have a passive preamp that I built myself from a kit (high end stuff - cost me $700 to build). Essentially this thing is just a bunch of relays and resistors to select a source and attenuate as desired.

The M2 is dead silent with no preamp attached. The preamp is dead silent with no AMP attached (I have hooked up headphones to check the outputs).

Once I connect the two, I always have a very low volume buzz coming from the midrange driver on my NS-1000s. It's sometimes hard to hear, but when you put your ear near it, it's usually there and sometimes gets a bit louder so it's noticeable a few feet away.

Any ideas?

Does it buzz with and active pre-amp connected ?
 
Well, I played around today.

M2 is not a problem, nor is my passive preamp.

I have a number of components I built, including my preamp and two DACS. All three components I built are designed with three prong AC plug and have chassis grounded with star grounding methodology employed. I can connect M2, preamp, and two DACs without issue.

The second I connect any piece of consumer equipment with a two pronged AC plug to my preamp, Bzzzzzzzz. This includes OPPO bluray player, Toshiba HDDVD player, and Yamaha T2 tuner.

Ground loop.

The Bluray and HDDVD players can easily be connected to my DAC to eliminate those issues.

But, anyone have a solution so I can at least connect the T2 without having this problem?
 
Last edited:
Back
Top Bottom