Using Headphone Jack As Output?

[JiminWales]

It might fix any matching problem with the phones output if you fit 610R 1/2 Watt resistors in each of the splitter cable mono plugs (wired across signal to ground so as to load the amp). I've done this in the past though that was to cure an AGC in the input concerned from over-reacting.

[pterm]

What you say makes sense. Yet I've also seen situations where I would get a deteriorated signal via the headphone when compared to a line-out; in both cases I had a standard PC sound card connected. This was years ago and not on a Nord (or other synth for that matter).

Now I may have just been driving the head phone output to 'hot'; I didn't have a scope back then I can can imagine that if I'd used a scope to match the levels on both outputs that I'd have gotten exactly the same quality signal.

Now that I'm thinking about it; would the noise floor me the same on both? In both cases noise coming into the amplifier would be reproduces, but wouldn't the amp itself also contribute slightly, regardless of volume/gain level? With the headphone output, wouldn't that have a higher amplitude?

The Electro2 Schematics show the Line-out is attenuated by a resistor-divider (no powered components) so it will have less noise at its output. The Headphone amplifier consists of an LF353 plus a Class B (transistors Q3 and Q5) output stage. The LF353 and the Class B stage of the Headphone amplifier introduces power supply noise onto the Headphone output.

That looks like good reason not to use the headphones path for external amplification.

An afterthought:
Power-supply noise might have contributed to the problems you saw on your PC. The powered amplifier for the headphones puts noise onto the headphone signal. I had a PC on which I could hear noises in my headphones when the HDD spun-up or when I moved the mouse. It got so annoying I looked into externally-powered headphone amplifiers. A new PC solved the problem.

[MyBucchi]

And if I use headphones output with this cable to audio interface? I just want to know does line out and headphones out have differences except volume level?

[MyBucchi]

Yes volume level and that includes probably more noise and the chance of easily saturating (not sure if damaging, someone knowledgeable might clarify this) the audio input. So if you are going to try anyway, try a very low volume from the kbd to start with.

[Ignatius]

In the spirit of looking in every key hole - I was frustrated with low output through the mains for a long time. Of course I would reach for the volume knobs, and sometimes the volume would just pop. That reminded me that presets and maybe even the standard configs seem to save volume levels as well as all the rest of the preset features. So when I run into this sudden low volume on a preset, I put it up where I want it and save it again, changing nothing else. This is now part of my set up routine before a gig, because it changes from room to room.

Of course, I am using a Nord Rack2, a simpler instrument than most of you, and also going to a very small set of presets all the time - one Rhodes with trem, One Wurli with trem, B3 with the lowest three drawbars out all the way a la Jimmy Smith, and one more preset with a split B3 keyboard for special occasions, hot on the right hand, cool on the left, so you might not relate to this. (Piano through a Korg SV-1 that is my MIDI driving keyboard for the rack, too.)

And you may have also already thought of this, and still hate the low level output. A little Behringer mixer (with channel boosts and a simple compression knob) in front of my powered speakers is helping me with this. Good hunting on a solution that works for you.

[Nadroj]

I thought I was knowledgable about this, but having read these posts, I'm now confused.

For weddings, etc, I run a single cable from the Left Mono out straight to our mixer - for other, bigger gigs, two unbalanced jacks from both line outs into DI boxes if I'm going in stereo - the DIs then send feeds to our wedges/IEMs, etc... For monitoring at weddings (where we use no sound guy and each cover our own monitoring - no DIs with floor wedges/IEMs, etc...), I run a single jack lead from the headphone out into one of the mono channels on my small Beringer monitor set up in front of me.

The Beringher has an unused stereo input - should I get a stereo jack cable like the one pictured above and run that into the monitor instead? I've only recently started doing it and was unaware that I could be potentially "damaging" the board as this solution was suggested to me by a sound tech.

EDIT: For the record, I am completely happy with the sound this gives me in my monitor.

[RedLeo]

If you are going to use the headphone output on the Stage, it's much better to use a stereo jack connected to the headphones output eg stereo jack out to two mono jacks (or two phonos etc). You don't have to connect both the jacks/phonos to the Behringer if you don't want to.

The reason for this is that if you plug a mono jack into the headphones output, you are shorting one of the headphone outputs to ground, which is a really bad idea, it can potentially damage the headphone output. It may be that the headphone outputs can take this abuse and survive, but you're still basically taking a risk.

As far as the sound quality of the headphones output goes, it used to be the case that headphone outputs were often significantly poorer in quality than the main outputs (much higher distortion and noise) but this is less the case nowadays as the quality of electronic components in headphone outputs is often much better. Unfortunately, Nord don't publish the specs for their outputs, so there's no way of knowing for sure. I'm sure they're fine for onstage monitoring, but I certainly would never record anything serious with headphone outputs.

Finally, the level and output impedance of headphone outputs are optimised for headphones (of course), which is quite different from the levels and impedances used for line level signals. Again, you can usually get away with it these days, but it's still less than ideal. If you realise that headphone outputs are basically miniature power amplifiers, and headphones themselves are basically miniature speakers, that should help give a clearer picture of what's happening here.