Sound output voltage


Still Fresh
Aug 27, 2010
Madrid, Spain

I heard how great the pandora audio is so I'm thinking about using my future pandora on a audio application. I need to know the output voltage of the jack output to see if i need to preamplify it.

If I don't want to use the built in speakers, can I use this audio line? is it more powerful?
Hitched my Pandora up to my Oscilloscope through the headphone jack.. Audio to volume to full... I ran a 1khz tone wave file.. I'm seeing a peak AC voltage of +/- 1.3V, so 2.6 Volts Peak to Peak.. It's late here and I'm a little rusty on my Math to calculate the True RMS voltage. I know the approximation for RMS voltage is .707 X Peak AC voltage.. so ~0.92 volts...

Now I'm not sure if this wave file is driving the amp to it's fullest.. but it's better than nothing.

Edit: plus I needed an excuse to use my Oscilloscope.
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The maximum output is 4.1Vpp if I remember correctly. I set the gain so that you can just slightly clip the output if you were to put a 0dB sine wave through it or something like that. TrashyMG's readings are more realistic values for anything audio but 4.1Vpp is the spec.
Picking up the sound through the ext connector is the shortest path to the soundchip therefore the less parasited ?
The EXT connector is line level so about 1.8Vpp. It is a line driver output so it should handle a decent amount of load but it is no headphone output.
So the conclusion is that the headphone jack is better than the ext line to connect a amplifier directly without preamp

I suppose that I can get the ext line with video out cable
It depends of the cable. Waiting for the mass production ones, they are currently hand-made by some members of the community, so they have not all RCA/cinch outputs/inputs.

In my opinion, for the best audio rendering/recording, you should use shortest as possible RCA/cinch ext cables, then preamplify. Mini-jack sucks for audio.
I drove my portable amp from the mini-usb which worked fine for me

Pandora + Ibasso d4 + sennheiser 558= amazing
Is the mass production cable going to happen anytime soon?

Can I configure the outputs?, for example play something through the ext line and other song through the headphone output. the same? only one line at a time?

the Ibasso d4 is a good idea because it has a gain switch
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