Hum or buzz through speakers

Newbee (time to change your name, dude) is most likely right. In addition to poor ground at outlet, could also be a bad IC ground, or induced hum from an IC or speaker cable near the power cord.

I had a 60Hz hum in my system due to an antenna/cable connection, when the TV was connected to my Jolida amp. The TV cable had a ground that is different from the electrical ground thus resulting in a ground loop.

Best way to find out is to disconnect all ICs from your amp but leave the speakers connected. If you still hear hum then it might be a problem with the amp. Then slowly start connecting one piece at a time, so that you find the faulty piece.

Good luck.

I love the Golden Dragon 6922's. They are great for the money or for any value. I've been using GD 6922's for about 5 years now and love them. The 12ax7's are quite good also. Very reliable, clean and unbiased sound.

Also, Steve designs his amps to be passive pre-amp friendly, i.e. high input sensitiviy. It may be something you'll have to live with.

Helo Eagleman -

The noise is most likely caused by a ground loop created by more than one piece of equipment with a 3-wire AC cord. This problem may also be caused by a cable TV connection if you have any audio signal cable connected from the TV (or any associated equipment) to your audio rig. Here is a link to a good explanation of ground loops and how to fix them: http://www.altavistaaudio.com/hum.html

If you ever want to know what the noise contribution of the amplifier is by itself, just unplug the interconnect cables and replace them with RCA shorting plugs in the amp's inputs. Shorting plugs are so-named because they make a connection from the center-pin (hot) to the outer ring (ground), thus "shorting" the input to ground. This will tell you what the intrinsic noise level of your amplifier is, and this can be useful information when you are troubleshooting system noise. A properly operating amplifier should be fairly quiet - there should be only a tiny amount of noise (or none at all) with your ear close to the speaker.

Beyond that, you should keep in mind that the DNA amplifiers run at slightly higher voltage gain than is typical. This means that the noise floor of your preamp may be more noticeable than it used to be, depending on what amp you have replaced. This is not usually an issue, but I have seen cases where a small amount of preamp noise that had previously gone unnoticed became audible (right at the speaker) with a DNA amp.

I hope this helps. Please call me at 760-732-0352, 10-6, M-F PST (California) if you would like to discuss this further.

Best regards,

Steve McCormack
www.SMcAudio.com