An unbalanced-to-balanced connection should use a 3-conductor (balanced) wire. The explanation behind this technique is somewhat complicated, and it is beyond the scope of this article. For an in-depth look at the technical explanation for this solution, read section 5.4, "Shield Wires", of The Clean Audio Installation Guide. ( http://www.benchmarkmedia.com/caig/ ) Impedance-balanced outputs can connect to unbalanced loads with the cold output 'floated' (unconnected) or connected to ground. There will be no performance or other differences between a floated or grounded cold conductor (pin-3) with impedance-balanced outputs. Using an XLR connector, this corresponds to pin-3 floating or tied to pin-1. The hot signal conductor will be connected to pin-2, as usual, and it will carry the audio information. The shield conductor will be connected, as usual, to pin-1. Devices with transformer-balanced outputs actively drive the primary winding of the output transformer. The secondary winding of the output transformer delivers a symmetrical signal to the hot and cold signal conductors. Such shorting, if done on a higher impedance mic level signal won't likely affect anything. I've seen people do that on line level signal, but I'm not sure if they're aware about any long term effects that might exist.

Most RCA audio cables that are built reasonably well with shielding can be run effectively from 100 to 200 feet." Strict practice requires the line be left balanced at the output (source) and unbalanced at the input. This is called floating a line.The transformer-based approach (like with Neutrik NA2F-DOB-TX or much more expensive Jensen transformers) will work and avoid ground loop issues. Transformers also have higher common-mode rejection ratio than what can be achieved with semiconductors. The distortion might not matter for use with tube amplifiers that already have a transformer in the signal path or with subwoofers. The way we've got round this on a PA installation I operate is to use unbalanced auxiliary outputs to drive the power amp. The main outputs on our mixer (a Yamaha MX12/4) are balanced XLRs so we use two of the unbalanced 1/4" group outputs to drive the (stereo) power amp, along with some careful selection of signal routing to get the correct signal out. So I would go ahead and do it the way you intended. If there is no hum or buzz, then you are fine. If there is then you should formally float the line as I described.

WARNING: This adaptor(TRS to RCA) is ONLY to be used for the Flex OUTPUTS. We've noticed a performance drop (15dB SINAD drop) when using such adaptor for INPUTS of the FLEX. For that reason, we do not recommend customers to use an unbalanced to balanced cable on the "input" side of the Flex. If you want to have unbalanced in/out for both inputs and outputs, it's strongly recommended that you just use the miniDSP Flex unbalanced version. The miniDSP Flex was engineered with best performance in mind and it's therefore our intention to stay consistent on making sure best audio quality is kept for this platform!

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I'm finding indications on-line that quality RCA cable is function up into the 30ft to 100ft (10m to 30m). I'm not sure I would use runs that long, but those are the numbers I'm finding. Pin 1 (sleeve/screen) is always ground. Pin 2 (tip) is always the positive deflection. Pin 3 (ring) is the negative deflection, So if you ever reverse pins 2 and 3 you create an out of phase condition. In this app note, we will demonstrate subwoofer integration for miniDSP'sstereoDirac Live processors using only the Dirac Live app for measurement

The main reason why two wires aren't enough for a high-performance audio interconnect is that no matter what you do, there will be current caused by a different ground potentials and/or a real-world interference flowing through the shield conductor. Since the shield conductor has a non-zero impedance, this current will produce a voltage and in case the shield conductor also doubles as a signal conductor, this voltage will be mixed straight into your audio. A TRS input is a balanced input. In balanced interconnection, the signal is defined by the voltage between the "cold" and "hot" conductors. There is a third ground/shield conductor, but it is only used to protect the system against interference and is NOT used to carry the signal. Devices with active-balanced outputs actively drive both the hot output and the cold output. The signal on the cold output is an inverted (polarity-reversed) version of the signal on the hot output. This creates symmetrical signals between the hot and cold outputs. This is the topology of all Benchmark equipment. The second "stereo" adapter is an unknown. It may be designed as an adapter to send a mono RCA signal to both stereo channels of a stereo TRS input. In that case the tip and ring would be connected together. If it's wired that way it won't work as a mono TRS to RCA adapter when connected to a balanced output. It may be wired with the Ring open. If so it will work as well as as TS adapter when connected to a impedance balanced output, but not at all if connected to a transformer balanced output.It might be either built inside or made as an outside box with separate power. The XLR shield and pin1 would need to be grounded to the chassis on the receiving side or the whole thing might be bolted to it. A company called THAT Corporation makes very good receiver chips that would fit this task and a module using those has even been a commercially available product at some point . Now the thing is that pins 2 & 3 in a balanced arrangement, never have a potential with respect to ground, just each other. IF you are going to do a XLR to RCA conversion, then a Transformer based device, as we assume the Sescom is, would be the best choice. Now for a balanced output, you can simply connect the + and GND terminals and ignore the -. This does not result in a "half wave" as was stated. Balanced signals work by transmitting 2 versions of the signal (completely out of phase with each other). On a devices input, the out of phase signal is inverted and the signals are now in phase and sum together. This provides common mode rejection (CMR) which is all designed at removing interference and improving SNR primarily to allow greater cable runs and premium quality for sensitive environments. Search common mode rejection for further details. One Rane Note was mentioned earlier, but they have a ton more and some specifically on balanced signals and CMR.