Re: [LAU] balanced <--> unbalanced

On Tue, January 10, 2017 12:15 pm, Ralf Mardorf wrote: Correct, NOT unbalanced out to balanced in, only balanced out to unbalanced in. (whether connection between - and GND is made close to ouput, or close to next device input) For noise reduction it can make a difference when cables are long, the connection difference changes whether the voltage difference between the two devices due to power line leakage currents is higher at the unbalanced input, or higher at the balanced output. For some types of balanced outputs which can float effectively on the common mode voltage the power line noise is lower with that connection. The other way that connection point makes a difference is that connecting at the input of the next device changes the capacitance which loads the grounded output. That could affect stability in some cases. By the way, what was the output level from the device with bad sound when connected to the unbalanced input? Section 1.2 of the paper I referenced earlier points out that when grounding one side of that style of output circuitry, the ungrounded leg will be driven +6dB to keep the nominal output level the same, which is twice the output voltage. If that drives the output into clipping, large currents can flow through the grounded side. If the output was near the listed device maximum it could have been clipping just slightly on peaks. I would not expect that, usually an unbalanced input is designed for lower limits, so I would expect the unbalanced input to clip before the balanced output even in single ended connection, but hard to know without checking. -- Chris Caudle