USB sound WITHOUT amp

[gbailes86]

Is it necessary to have the amp (I'm using the Adafruit one) when you are going the USB sound card route? I thought I've seen others on here go this route but I cannot seem to find the threads.

I have sound working from the USB sound card through the headphone jack (using mostly Cannikin's guide) but I cannot for the life of me get the sound out of the speaker no matter how I wire it to the headphone jack.

Is this scenario possible or do I HAVE to use the amp as well?

Thanks!

[Fleder]

That depends on the DAC you are using.
Some are good enough to boost the Speaker, some are not.
You can try to push the volume up really high in alsamixer and see if it works.
Always check if your speaker is working before you tinker around.

I managed to make it work without an amplifier, but the volume was too low for my taste,
so i just went with the amplifier option, which does not really eat up much space anyway.

[gbailes86]

I'm using the Sabrent one that was recommended. The volume was a bit low coming from the headphones but after it was boosted in the RetroPie menu, it's fine.

How did you have your speaker wired without the amp before? Maybe my speaker is bad...

[gbailes86]

Any ideas?

Also, how would I check to see if my speaker is bad?

Thanks again!

[chiz]

You confirmed that your headphones do produce audio at an acceptable level, right? I have a spare headphone that I opened and used the speaker for testing. What I found out is that it produces louder audio compared to an 8-ohm mini speaker. Unfortunately, the headphone speaker will not fit in the GB case speaker cavity.

I've researched the typical impedance/resistance of headphone speakers but did not find any conclusive information as to why headphone speakers sound louder compared to the 8-ohm mini speakers usually used in toys and DIY projects. I ordered a 4-ohm, 16-ohm and 32-ohm speakers that yet to arrive in the mail so I can experiment which speaker produces the loudest audio with the USB DAC alone, i.e., no separate amp used.

[Kilren]

gbailes, I had the same problem as you did. The headphone audio was quite decent but the 8ohm speaker had very little output. It was hard to hear in a quiet room. I had to solve it using an amp in conjunction to the sabrent

[chiz]

@Kilren

When using the amp, do you experience sudden power dips when you set your audio too loud? One reason I want to eliminate the use of an amp is it's going to be another component that will drain the battery.

[Kilren]

@Kilren

When using the amp, do you experience sudden power dips when you set your audio too loud? One reason I want to eliminate the use of an amp is it's going to be another component that will drain the battery.

I haven't done a battery test, so I can't tell you the effect overall. However, I haven't noticed anything too crazy when just plugged in. I think that'll heavily depend on which amp is used. I'm really behind because of work, hoping to have this finished in the next two weeks. I just got done working way way too much this last week.

[Fleder]

I'm using the Sabrent one that was recommended. The volume was a bit low coming from the headphones but after it was boosted in the RetroPie menu, it's fine.

How did you have your speaker wired without the amp before? Maybe my speaker is bad...

Oh, i'm sorry. I completely missed your question.
I do not have a wiring diagram of it and i changed it now, to get louder volume. Sorry.

I am currently experimenting with different speakers to find a better solution.
I even considered altering the headphone jack and only feeding left audio to the speaker and right to the headphones,
so i would be able to use alsamixer to even out the volume differences of those 2 output devices,
since you can change left and right channel volume independently.
That way, headphones and speaker would both be nearly the same volume,
not like, speaker is barely understandable and the headphones make your ears bleed.