SynonZelra
Posts: 8
Joined: Sun Jan 11, 2015 10:07 am

RPi audio solution discussion

Sat Jan 17, 2015 7:26 am

Greetings everyone.

I'm working on the audio part of my pi. Basically, I wanna the audio part works like an iphone.

My Target:
1) built-in speakers, but when the 3.5mm jack inserted, it works on the earphone.
2) buttons to volume up or volume down.
3) a mute button. (optional)

My research:
a) I find a connector in the local market, which meets target 1, pretty clear and easy.
REF:http://www.ebay.com/itm/20Pcs-3-5mm-Fem ... 1486756940
b) I read some threads says that if you use the audio from 3.5mm on pi, you'd better control the volume via an audio amplifier and keep the system 100% output.
c) I searched through ebay to look for some audio amplifier, there're basically 3 kinds.
c.1) Adfruit kit. seems everything on it, but a little expensive. Link: http://www.ebay.com/itm/Adafruit-Stereo ... 1387905614
c.2) some third-party kit. also everything on it, also expensive (even more). Link: http://www.ebay.com/itm/mini-USB-audio- ... 1114540729
c.3) the very basic board. really cheap but requires a lot more work. Link: http://www.ebay.com/itm/DC-5V-2x3W-Digi ... 1578760302

My concerns:
i) my idea is that the audio from pi goes to an audio amplifier, and the audio amplifier goes to the connector which holds speaker and earphone jack, is it possible?
ii) I've noticed that an audio amplifier works on 3.3v or 5v usually goes with the speaker up to 8 ohms, but we know the every earphone is 32 ohms, is this okay to match?
iii) if I power it from the GPIO pins, is it enough ?
iv) any other better solution ?

Sincerely thanks

fruitoftheloom
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Location: Delightful Dorset

Re: RPi audio solution discussion

Sat Jan 17, 2015 7:46 am

Retired disgracefully.....
......to an uncomplicated life !

Rather than negativity think outside the box !

BMS Doug
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Location: London, UK

Re: RPi audio solution discussion

Sat Jan 17, 2015 8:13 am

I'm not sure how that HAT would give him the onboard speaker he is looking for, are you suggesting that his onboard speaker should be connected to the left and right outputs?
He'd still need an amplifier circuit and I don't know if it would automatically switch to the headphone output if a headphone was inserted into the jack.

Edit: ah, if he adds a pi amp+ on top then the amp issue is solved, just add speakers. Hopefully iqaudio have added the autodetect to cut off speakers when headphones inserted.
Doug.
Building Management Systems Engineer.

fruitoftheloom
Posts: 22055
Joined: Tue Mar 25, 2014 12:40 pm
Location: Delightful Dorset

Re: RPi audio solution discussion

Sat Jan 17, 2015 9:13 am

BMS Doug wrote:I'm not sure how that HAT would give him the onboard speaker he is looking for, are you suggesting that his onboard speaker should be connected to the left and right outputs?
He'd still need an amplifier circuit and I don't know if it would automatically switch to the headphone output if a headphone was inserted into the jack.

Edit: ah, if he adds a pi amp+ on top then the amp issue is solved, just add speakers. Hopefully iqaudio have added the autodetect to cut off speakers when headphones inserted.
He stated speakers plural not speaker single, therefore one would assume he wanted stereo ?

He stated works like an iPhone, why would he need more ??

"" built-in speakers, but when the 3.5mm jack inserted, it works on the earphone. ""


If the OP contradicts himself then just try to get lowest common denominator which is IQ which supports HD Audio and a Headphone Jack

Until the OP states what he really trying to achieve you are just being picky :roll:
Retired disgracefully.....
......to an uncomplicated life !

Rather than negativity think outside the box !

BMS Doug
Posts: 3824
Joined: Thu Mar 27, 2014 2:42 pm
Location: London, UK

Re: RPi audio solution discussion

Sat Jan 17, 2015 9:24 am

fruitoftheloom wrote:
BMS Doug wrote:I'm not sure how that HAT would give him the onboard speaker he is looking for, are you suggesting that his onboard speaker should be connected to the left and right outputs?
He'd still need an amplifier circuit and I don't know if it would automatically switch to the headphone output if a headphone was inserted into the jack.

Edit: ah, if he adds a pi amp+ on top then the amp issue is solved, just add speakers. Hopefully iqaudio have added the autodetect to cut off speakers when headphones inserted.
He stated speakers plural not speaker single, therefore one would assume he wanted stereo ?

He stated works like an iPhone, why would he need more ??

"" built-in speakers, but when the 3.5mm jack inserted, it works on the earphone. ""


If the OP contradicts himself then just try to get lowest common denominator which is IQ which supports HD Audio and a Headphone Jack

Until the OP states what he really trying to achieve you are just being picky :roll:
He definately wants built in speakers, so the amp kit needs to be added if he uses the dac kit.

Heck, if he wants it to be like the iphone then we should definately find him the most expensive solution with the least functionality.
Doug.
Building Management Systems Engineer.

SynonZelra
Posts: 8
Joined: Sun Jan 11, 2015 10:07 am

Re: RPi audio solution discussion

Sat Jan 17, 2015 9:47 am

hi guys.

sorry maybe there's misunderstanding.

1. I want a stereo, and I'm also looking for the stereo amp.
2. I'm an amateur, and I love do something on this, but I can't do complicated work now.
3. basically, I have found a connector that automatically disconnect the speaker when you insert the earphone into the jack, so I need an amp with some controlling function like volume control.
4. HD audio will be awesome, for sure. some amp can be even more expensive than a pi, so I wanna have a balance between quality and price.
5. I don't know about the power consumption, is it enough to power an amp as well as the speakers (like two speakers in 8 ohms, 0.5 watt)?

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davidcoton
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Location: Cambridge, UK

Re: RPi audio solution discussion

Sat Jan 17, 2015 11:01 am

SynonZelra wrote: i) my idea is that the audio from pi goes to an audio amplifier, and the audio amplifier goes to the connector which holds speaker and earphone jack, is it possible?
ii) I've noticed that an audio amplifier works on 3.3v or 5v usually goes with the speaker up to 8 ohms, but we know the every earphone is 32 ohms, is this okay to match?
iii) if I power it from the GPIO pins, is it enough ?
iv) any other better solution ?
i) Find an amplifier board which also supports an earphone jack (or wire the earphone jack to the output to disconnect the speakers -- standard stuff). Drive it from the Pi audio jack. Note the jack is different on the + models (4 pole) and correct wiring is essential!
ii) Higher impedance (above 8 ohms) is fine, but it won't do lower (lower draws more power).
iii) Depends on the power. GPIO supply pins are limited, but probably OK for low powered speakers as long as the power supply and its cable are adequate. Probably better to power the amp directly from the power supply, not through the Pi, if there are other GPIO or USB peripherals drawing power through the Pi.
iv) I have none to had
SynonZelra wrote: b) I read some threads says that if you use the audio from 3.5mm on pi, you'd better control the volume via an audio amplifier and keep the system 100% output.
For best audio, yes. For best program control, no.
SynonZelra wrote: 5. I don't know about the power consumption, is it enough to power an amp as well as the speakers (like two speakers in 8 ohms, 0.5 watt)?
You need to check the amp spec for its input supply current, but 0.5W output is not much power from a supply ([email protected]=10W)
Signature retired

Bruny
Posts: 159
Joined: Fri Feb 06, 2015 5:22 pm

Re: RPi audio solution discussion

Fri Oct 09, 2015 3:53 pm

SynonZelra wrote:Greetings everyone.

I'm working on the audio part of my pi. Basically, I wanna the audio part works like an iphone.

My Target:
1) built-in speakers, but when the 3.5mm jack inserted, it works on the earphone.
2) buttons to volume up or volume down.
3) a mute button. (optional)
My target would be to use buttons from headset.

Yet to find USB adapter based on TS3A227E 8-)

Woll
Posts: 472
Joined: Mon Jul 06, 2015 2:14 am
Location: Cloud Cuckoo Land

Re: RPi audio solution discussion

Fri Oct 09, 2015 4:39 pm

On the Raspberry Pi Guy's video for Picade Arcade Cabinet review, it states you can use speakers or a headphone in the 3.5mm jack.
If you copy this aspect of his design, you can use it in your project as it looks like it can be done.

http://www.theraspberrypiguy.com/raspbe ... et-review/
Who ate all the Pi's? Who ate all the Pi's?
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Who ate all the Pi's?

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