How to use Pandora as an amplifier

[Askarus]

Hey, there's some Idea I had.

My situation:

I have a pair of good speakers at home.

They are not powered.

That means sound is pretty quiet.

Pandora now has an build in amplifier which makes my Pandora the only device that can use them nicely.

Now as the TV-out cables have also audio-in wouldn't  it be nice to use the Pandora as an amplifier?

How can I grab the input from the TV-out cable, make it louder with hardware/software and output it via the headphone jack?

 

[mcobit]

The pandora has a preamp, granted, it is a loud and good one but I don't think it can drive your speakers very loud.


It is made for headphones and can barely drive the internal speakers to some loudness.


You could look for some 3w digital usb amps though as you can find on Amazon from china.

 

[Askarus]

At least Pandora is much louder than my Laptop.

I don't need it pretty loud.

It's for gaming and not for big partys.

 

[mcobit]

So what resistance do your speakers have?


4ohms will be louder than 8.


Edit: Also I am not sure if there is some resistor at the headphones out (I suppose you use that to connect to your speakers) to protect your ears a bit.


If you want to open the top half, you could try to connect your speakers directly to the solderpoints of the internal speakers to see if they are louder then.

 

[WizardStan]

I don't know how exactly to access the line in, but redirecting the microphone to the speakers was as easy as

cat /dev/dsp > /dev/dsp

A more appropriate way is with arecord and aplay. Something like

arecord -D=twl4030-hifi-1 --buffer-size=100 | aplay --buffer-size=100

tiny buffer size to prevent lag but could cause some stuttering, may need to play with that a bit. And I may not have the device name correct. Maybe try not specifying a name at all, I guess the mixer could be smart enough to select both lineout and microphone and combine them if they're both sourcing audio.

 

[Askarus]

@ Mcobit

What I need is a tool that grabs the input from TV cable and outputs it via headphone.

Impedance of speakers is 6 Ohm.

Don't worry about my ears .

I don't like music if it's too loud.

Other devices than the Pandora are nearly not hear-able.

Pandora is not the problem.

I don't know how to grab the input and output it.

@ WizardStan:

Error:

ALSA lib pcm.c:2211snd_pcm_open_noupdate) Unknown PCM =twl4030-hifi-1

arecord: main:608: audio open error: no such device

aplay: playback:2297:read error

 

[TrashyMG]

So I played with the Audio Inputs just now... 

First Enable the line IN with the Mixer by going in and disable the Analog Left & Right Mic inputs by un-checking them and enable Analog Left ( AUXL) and Right (AUXR).. **IMPORTANT** Turn the Capture slider almost all the way down!. By default it's at 100% but the gain is way over kill, must be used to drive microphones.. 

To output the audio to speakers or headphones run this.. 


arecord -f cd -D hw:0,1 | aplay  --buffer-size=100
Edit: Wow.. The Pandora makes my phone's audio output sound good.

 

[Askarus]

^

You rock man.

Thanks a lot.

It works great.

Why do I need it?

Most crazy thing ever.

I can't find the audio out of my TV but wan to play with my WiiU with big speakers.

Solution:

Capture the Sound of the WiiU gamepad which has a headphone jack with the Pandora , make it loud and play sound with big speakers.

That's how a Pandora has to be used.

EDIT:

Warriors Orochi 3 Hyper is so much better with good speakers.

(At least they're better than slat screen TV speakers)

 

[WizardStan]

Ahah, I knew I was looking at the wrong string for the device name. It looked completely wrong (sorry) but it'd been so long since I'd done anything with arecord/aplay I'd forgotten what it was supposed to look like. Thanks TrashyMG, this is actually a really useful thing to know.

 

[mcobit]

Sorry, completely misunderstood your usecase

 

[Askarus]

Do we also have a PND which can be used to modify the sound?

For example: filters, make it even louder, effects, add a second audio line.

 

[mcobit]

That could be a decent use for the dsp.


But I think right now there is no such pnd.

 

[peelie]

 

So I played with the Audio Inputs just now... 


First Enable the line IN with the Mixer by going in and disable the Analog Left & Right Mic inputs by un-checking them and enable Analog Left ( AUXL) and Right (AUXR).. **IMPORTANT** Turn the Capture slider almost all the way down!. By default it's at 100% but the gain is way over kill, must be used to drive microphones.. 


To output the audio to speakers or headphones run this.. 

arecord -f cd -D hw:0,1 | aplay  --buffer-size=100
Edit: Wow.. The Pandora makes my phone's audio output sound good.

 

i am getting underun messages? no audio?


trying to play my phone output to pandora speakers


thanks

 

[TrashyMG]

Well you should get a few messages until it buffers properly.. If it's giving you nothing but buffer under-run errors something isn't working right.

Did you enable the line in the mixer control as I posted?, is the capture volume set high enough to capture some audio?

 

[peelie]

yah followed your instructions. does capture record button need to be on? tried it with it on and off no effect.


thanks


edit/ doh input is from tvout port no? was using headphone port as input! works from tv-out!


this is great i have option now not to take my portable speakers

 

[TrashyMG]

yah followed your instructions. does capture record button need to be on? tried it with it on and off no effect. thanks

It should be on I think, what is the slider set to?

Can you also confirm that Analog Left ( AUXL) and Right (AUXR) are enabled not the Mic ones.

 

[cube48]

Do we also have a PND which can be used to modify the sound?

For example: filters, make it even louder, effects, add a second audio line.

Try SunVox ... it's fully modular audio lab with Input module. So you can route the signal through effect chain of your choice.

Just set the right Input in Audio setting of the Preferences menu. Mic input can be effected with it and line-in should work too.

Edit: Check the tutorial #1 and #15 to get quick idea how to route the modules ;-)

http://www.youtube.com/playlist?list=PL62F503E7722DB7CC

 

[peelie]

shame input is not stereo; but you can now audio mix an outside audio sources with audio from pandora

 

[TrashyMG]

^the input from the line in using the TV cables is stereo.

The Microphone is an oddity though.. the Microphone is one channel and the input from the headphone jack is one channel..

Also I was assuming you were using the TV cables for this not the headset jack in the front.

 

[peelie]

 

^the input from the line in using the TV cables is stereo.


The Microphone is an oddity though.. the Microphone is one channel and the input from the headphone jack is one channel..


Also I was assuming you were using the TV cables for this not the headset jack in the front.

 

okay so my tvout cable is probably duff for audio input