Buzzing in Speaker

[Klint]

SNR / dynamic range referred to either full power or 2.83 V (1 W / 8 ohm). The latter would be 4 dB lower than Amir's 5 W dynamic range. There's only one amp in Amir's chart that clears 112 dB of 5 W SINAD, that's the Benchmark AHB2, but I'd rather assume that a Topping PA5 would be fine, too.

Thanks

 

[antennaguru]

An old trick on checking grounds (in USA) is to get a couple of 3 prong to 2 prong AC plug adapters. Then file down the "fat" prong so it is the same width as the thin prong. They are brass prongs, and used to be made with the same width prongs "in the old days".

Plug the adapter onto the end of your polarized or 3 prong line cord, and then try orienting the adapter both ways in the outlet to see if one orientation is quieter than the other orientation. Mark that orientation for future reference.

Alternatively put one probe of a VOM set to AC volts (should auto-range to millivolts) on the ground screw of the electrical outlet, the screw that holds on the outlet cover, and the other probe on a good chassis ground like a chassis screw head on the electronics. With nothing else connected to that piece of electronics (no interconnects) measure which adapter plug orientation has the lowest voltage between the chassis and the outlet ground screw. That would be the best way to plug in that piece of electronics. Do that with every piece of electronics and get them all plugged in the best way. Sometimes one unit has the neutral and line reversed inside the unit and that needs to be corrected. The adapter plug trick will reveal this, but shouldn't be a long term solution from a safety standpoint.