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External DAC to prevent double-amping?

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#1
I'm playing music from my MacBook. I (will shortly) have a JDS Atom amp. It seems the only way I can get audio to the amp is to use the headphone jack, which passes through the computer's internal DAC and amp (there is no TOSLINK on this model).

This leads to "double amping" from both the internal and external amps. I've heard this is bad, though I'm not sure whether that's true.

Question: would buying a good $100-200 external DAC to bypass the internal amp produce any improvement in sound quality?

(I realize the Mac's DAC itself is fairly good. The goal would not be to improve upon it, but rather address any quality loss from the double amp issue.)
 

twsecrest

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#2
Plug the Atom directly into the MacBook's headphone jack.
Max out the volume controls on the Mac, to send a strong signal to the Atom.
Just use the Atom's volume knob to control loudness.
And of course turn the volume knob on the Atom way way down, before maxing out the Mac's volume controls.
If you still want to get a USB DAC, go for it.
https://drop.com/buy/topping-d50-dac
 

Blumlein 88

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#4
I'm aware that's how the amp works. I'm wondering more about the possible advantage of using a DAC.
There is almost certainly a measured advantage in noise levels and distortion should you use an external DAC to feed your headphone amp. One of the good ones in your price range with USB input should do the trick. How much difference you'll hear, I'm not sure. The output from the Mac is probably not very high in level so feeding it to the amp would work just fine. Why don't you try it with your amp prior to deciding on also buying a DAC. It may sound so nice you've no reason to worry further.

If your Macbook has USB-C or you have an iphone that does, for $9 you can try an Apple USB-C dongle to feed your JDS amp. If the improvement is worthwhile you can buy a good DAC. Amir reviewed it here, and its performance is very respectable for peanuts if you have USB-C.

https://www.audiosciencereview.com/...pple-vs-google-usb-c-headphone-adapters.5541/
 
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#5
If your Macbook has USB-C or you have an iphone that does, for $9 you can try an Apple USB-C dongle to feed your JDS amp. If the improvement is worthwhile you can buy a good DAC.
https://www.audiosciencereview.com/...pple-vs-google-usb-c-headphone-adapters.5541/
Thanks, I'll try this. If there's an improvement, I can get an "adult" amp. And if the sound gets worse, that proves DAC quality matters.

Of course, it could be just worse enough than the built-in one that the improvement from making it external cancels it out, but hey, for $10 it's worth a shot.
 

twsecrest

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#6
I'm aware that's how the amp works. I'm wondering more about the possible advantage of using a DAC.
I do not see a real quality loss with plugging a headphone amplifier into the Mac's headphone jack.
When the Atom arrives, plug it into the Mac and see if the music get worse or stays the same or even improves.
I've spent a lot of time on the website Head-Fi, so far I've post on Head-fi somewhere over 30,000 times.
Do not recall people posting with negative feedback on plugging a head amp into a Mac's headphone jack.
For it being worth getting an external DAC?
It might help to know what type of music you listen to?
What source(s) the music is (old mp3 or new mp3 or FLAC or ALAC or streaming service?
What headphone do you use or are planning on buying in the near future?
 

JJB70

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#7
Try and decide. One thing I would say is that I wish I had a pound for every time I have heard someone complain that they have bought an external DAC based on the usual reviews and claims of night and day differences only to find it sounds just the same. I think a good amplifier (and the Atom is one of the best) does make a difference as many device headphone amplifiers are rather gutless, but I am rather sceptical about DACs unless you have one of the badly designed outliers. And Apple computers and devices tend to have good DACs.
 
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#8
It might help to know what type of music you listen to?
What source(s) the music is (old mp3 or new mp3 or FLAC or ALAC or streaming service?
What headphone do you use or are planning on buying in the near future?
Hi, I listen to mainly rock and indie music (guitars, drums, bass, vocals). The source is Spotify (on high quality). I own a Sennheiser 58X and may upgrade soon (see companion thread in this forum).

Try and decide. One thing I would say is that I wish I had a pound for every time I have heard someone complain that they have bought an external DAC based on the usual reviews and claims of night and day differences only to find it sounds just the same. I think a good amplifier (and the Atom is one of the best) does make a difference as many device headphone amplifiers are rather gutless, but I am rather sceptical about DACs unless you have one of the badly designed outliers. And Apple computers and devices tend to have good DACs.
Yes, I am extremely skeptical. By all accounts the MacBook DAC is quite good. My guess is any advantage would come from it being external versus internal and avoiding double-amping, if such an advantage exists at all.
 
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#9
Is that the D50 or D50s ? I seem to recall there were some improvements in the S model...
 
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#10
After some more research, I can ask a more precise question.

Will the average person hear a difference in a ABX volume-matched comparison between the mac headphone jack output and a Topping D50s connected via USB, both run through a JDS Atom into 58X headphones?
 

JJB70

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#11
After some more research, I can ask a more precise question.

Will the average person hear a difference in a ABX volume-matched comparison between the mac headphone jack output and a Topping D50s connected via USB, both run through a JDS Atom into 58X headphones?
I suspect that depends on what constitutes an average person and the volume level. I suspect that if used at a level before distortion lifts off and clipping starts the Apple output will sound just the same to the vast majority of people in a level matched ABX.
 
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#12
I suspect that depends on what constitutes an average person and the volume level. I suspect that if used at a level before distortion lifts off and clipping starts the Apple output will sound just the same to the vast majority of people in a level matched ABX.
Thank you.

Has it been confirmed that distortion and clipping do appear at max volume? How far below max volume must one be to avoid both?
 
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