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Advice for dedicated amp to save laptop battery and boost signal to Bose speaker

cedd

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Apr 9, 2021
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My 2020 Macbook Air's 3.5mm out is my source and I'm looking to use its lowest volume setting to conserve battery. The problem with going directly to the Bose speaker is that I get some static when I turn up its volume to comfortable levels. The Bose isn't grounded as the cord that powers it has no ground prong. Would getting a small dedicated amp be a good solution? How much power would I need to eliminate this noise floor? Would a headphone amp be enough?

Also I thought about soldering a wire from the ground of the audio cable to a ground prong that I'd plug into the ground socket of the outlet. Would that be worth a try as well?

EDIT: I'm currently using a 6ft cable. Would making a custom 1ft cable with a very low gauge be worth a try? Like a comically low gauge for a wire of that size... 14AWG or something.
 
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If the Bose is an active speaker the volume setting has no effect regarding battery usage.
The static noise could be clipping (volume too high).
 
If the Bose is an active speaker the volume setting has no effect regarding battery usage.
The static noise could be clipping (volume too high).
Yeah, it's active. The volume setting I'm trying to limit is from the source: the laptop.
 
When plugged into an active speaker, the MacBook's battery life stays the same no matter what the volume is set to.
That's because the input of your Bose speakers is super high impedance, and so your MacBook is outputting almost zero current. No current -> no battery drain.

Set your MacBook to max volume (that's how you get the cleanest signal), and turn down the Bose. Is there still static?
 
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See the up above posts about battery life:

Also I would recommend against a heavy duty cable; 3.5mm jacks can be fragile.
 
> that I get some static when I turn up its volume to comfortable levels.

I think the noise you're getting is more because of reduced Signal-to-Noise ratio, since you turned your mac's volume down. I don't thing grounding has anything to do there, if it was ground, you'd be hearing a 50 or 60 hz hum too.
Concur with the others on increasing the volume in your mac.
Luck!
 
I get CPU/GPU noise from my Mac's headphone jack or USB port under most circumstances that are not headphones. While it may sound like static (I think of it as more of a buzzing myself), CPU/GPU noise is a little different in that if you focus on the sound, you'll normally notice it's coupled to mouse movements, dragging windows, or gaphical activity on the screen. If this is what you are experiencing, keep reading, otherwise ignore this.

I don't have any free or super cheap effective solutions, but the one fix that always works is to decouple all wired connections between the audio equipment and computer. An easy way to do this is by using a USB > optical media converter (Topping D10s for example) > optical cable > DAC > preamp/amp. The optical cable has no metal and acts as an air gap to decopule the CPU from your audio system and will effectively isolate CPU/GPU noise. Another way to do it is via wireless, but the lag makes for an aweful zoom experience, so I highly recommend against it. There may be other ways to fix it, but they are hit and miss and not a fool proof as using an optical cable to decouple.

CPU/GPU noise is one of the annoying problems of using a computer as a source. It doesn't affect everybody, or even most people, but for those that it does affect it's generally a pain in the butt.
 
When plugged into an active speaker, the MacBook's battery life stays the same no matter what the volume is set to.
That's because the input of your Bose speakers is super high impedance, and so your MacBook is outputting almost zero current. No current -> no battery drain.

Set your MacBook to max volume (that's how you get the cleanest signal), and turn down the Bose. Is there still static?
Thanks for explaining that! I realize now this sound is the familiar "speaker on" sound. You know when you turn the volume of a speaker up high and you can hear that operation hiss? I'm guessing it's the interference sounds of the components inside the Bose's amp itself. It's a little annoying but I can't notice it when music is playing. Have any amp manufacturers tried to eliminate that noise? It seems like it would be a tough one to get rid of but as someone who likes to listen at low volumes I would be interested in a product that offered that.
 
@cedd it's really not as big of an issue as you may think. The reason your Bose plays static is because your MacBook outputs a super quiet signal and to compensate, you're putting the Bose to maximum amplification.
It's natural that there will be noise this way.
It's not how you're supposed to use the speaker.
Just turn up your MacBook and turn down the Bose and the static/noise/hiss will disappear.
 
@cedd it's really not as big of an issue as you may think. The reason your Bose plays static is because your MacBook outputs a super quiet signal and to compensate, you're putting the Bose to maximum amplification.
It's natural that there will be noise this way.
It's not how you're supposed to use the speaker.
Just turn up your MacBook and turn down the Bose and the static/noise/hiss will disappear.
Yeah I do have the mac turned up all the way but there's still the low operational hiss of the Bose just being on. I can't guess what dB value it is but it's very low and only really noticeable because my head is about 1ft from the speaker. It's a tiny annoyance but I wondered if that operational hiss was something any products aimed to solve (achieving COMPLETE silence when the amp+speaker is on but no audio being played).
 
I wondered if that operational hiss was something any products aimed to solve
A higher quality amplifier than what's built into the Bose would reduce the noise. This is not something you can alleviate with an external "add-on".
And replacing the built-in amp with a low noise alternative is no easy feat.
 
Yeah that's what I
A higher quality amplifier than what's built into the Bose would reduce the noise. This is not something you can alleviate with an external "add-on".
And replacing the built-in amp with a low noise alternative is no easy feat.
That's what I figured. What is the operational noise referred to in tests and specs? Just "operational noise" or is there some other term? Usually this noise gets a bit louder as you turn the amp up.
 
I get CPU/GPU noise from my Mac's headphone jack or USB port under most circumstances that are not headphones. While it may sound like static (I think of it as more of a buzzing myself), CPU/GPU noise is a little different in that if you focus on the sound, you'll normally notice it's coupled to mouse movements, dragging windows, or gaphical activity on the screen. If this is what you are experiencing, keep reading, otherwise ignore this.

I don't have any free or super cheap effective solutions, but the one fix that always works is to decouple all wired connections between the audio equipment and computer. An easy way to do this is by using a USB > optical media converter (Topping D10s for example) > optical cable > DAC > preamp/amp. The optical cable has no metal and acts as an air gap to decopule the CPU from your audio system and will effectively isolate CPU/GPU noise. Another way to do it is via wireless, but the lag makes for an aweful zoom experience, so I highly recommend against it. There may be other ways to fix it, but they are hit and miss and not a fool proof as using an optical cable to decouple.

CPU/GPU noise is one of the annoying problems of using a computer as a source. It doesn't affect everybody, or even most people, but for those that it does affect it's generally a pain in the butt.

Hmm, I never knew lag was ever a problem in wireless for zoom. Instead poor/weak wireless signal is the main cause.
 
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