Adafruit Audio FX Sound Board + 2x2w Amp : How to make it LO

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can_da
 
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Adafruit Audio FX Sound Board + 2x2w Amp : How to make it LO

Post by can_da »

Hey,

I purchased a few :
- Adafruit Audio FX Sound Board + 2x2w Amp
- And a few Adafruit 4 ohm 3 watt speakers


MAX VOLUME DEMO : https://youtu.be/UwdZP8Rx23s


I loaded the sample tracks onto the board, soldered 2x 4ohm speakers on (to correct -/+ ports) and tested the sound while powered with portable usb and 12v car battery (with step down 5v).

The tracks play but it is not very load at all regardless of the power source.

I tried to turn up volume on the board by hitting vol + terminal with ground, but it would not turn up the volume any more (I could only turn down the volume using vol -) So it looks like I have the best power supply, best speakers and board volume is up to the max. Yet - the volume is quite low (below indoor speech volume)


Is there anything I can do to increase the volume. I need the volume to be load enough that you can hear the sound in a boat while out on the water.


Thank

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adafruit_support_mike
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by adafruit_support_mike »

You'll probably need a more powerful amplifier.

The 2W amp on the FX Board is made for things like interactive toys, and the environment where you want to use it will be louder. The biggest amp we carry is the 20W MAX9744:

https://www.adafruit.com/product/1752

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can_da
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by can_da »

Thanks for the info.

Can the 20w amp be soldered to the soundboard and use the sound boards power source?

Thanks

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adafruit_support_mike
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by adafruit_support_mike »

You can connect the FX Board's L, R, and GND pins to the MAX9744's inputs. The GND pins are the negative connections for both channels.

To get maximum voltage out of the MAX9744, you'll need to power it at a voltage higher than the FX Board can survive. If you're working in a 12V system, power the MAX9744 at 12V.

The audio power that comes out of a speaker is proportional to the square of the voltage across it, based on the power formula P=V^2/R. To get 20W, you need at least 9V across the speaker, and the amplifier needs additional headroom to operate.

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can_da
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by can_da »

Thanks.

So best setup for the loudest soundboard would be:

Adafruit Audio FX Mini Sound Board - WAV/OGG Trigger - 2MB Flash(powered from our 12v power supply with 5v step down)
https://www.adafruit.com/product/2342

FX Board sound channels connected to MAX9744, MAX9744 powered directly from 12 v battery
https://www.adafruit.com/product/1752

MAX9744 powers 2x 20W 4 Ohm Full Range Speaker
https://www.adafruit.com/product/1732


Could you recommend a splash proof casing that I could securely fit this system into?

Would an AUX connection between the FX board and MAX9744 give better sound quality/louder?

Thanks

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adafruit_support_mike
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by adafruit_support_mike »

Those parts will work together, and should be significantly louder than the FX Board by itself.
can_da wrote:Could you recommend a splash proof casing that I could securely fit this system into?
I'm afraid not. We've used OtterBox products for waterproof systems in the past, and they have a good reputation, but the more reliably waterproof something is, the more it tends to block sound.
can_da wrote:Would an AUX connection between the FX board and MAX9744 give better sound quality/louder?
The connection between the boards shouldn't have any effect on the output volume.

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kala
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by kala »

Then what would be the best way to make it play through a PA system ?
thks.
can_da wrote:Thanks.

So best setup for the loudest soundboard would be:

Adafruit Audio FX Mini Sound Board - WAV/OGG Trigger - 2MB Flash(powered from our 12v power supply with 5v step down)
https://www.adafruit.com/product/2342

FX Board sound channels connected to MAX9744, MAX9744 powered directly from 12 v battery
https://www.adafruit.com/product/1752

MAX9744 powers 2x 20W 4 Ohm Full Range Speaker
https://www.adafruit.com/product/1732




Thanks

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adafruit_support_mike
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by adafruit_support_mike »

It depends on what the PA system wants as input.

If you can connect something like an MP3 player to the PA system, the FX Board will work the same way.

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kala
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by kala »

Hello
While running the basic tests (didn't solder closed to turn it into analog mode yet), I did attach a cinch cable to both of the outputs, then plugged them into a -10dBu input of the mixer, well the sound is totally mashed up (I thought it would). Maybe i could add a 1K resistance to the outputs to lower the level, what do you think ?
Thks
K
Oops i didn't precise i was working with the stereo 20W amplifier. Maybe I should post it somewhere else ...

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adafruit_support_mike
 
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Re: Adafruit Audio FX Sound Board + 2x2w Amp : How to make i

Post by adafruit_support_mike »

Putting resistance in series with the output won't do anything useful.

Post a photo showing your hardware and connections and we'll take a look. 800x600 images usually work best.

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