Android phones and USB DACs - Page 95

Quote:

Originally Posted by Theogenes 

 

If what you had is just an amp, then nope, it sounds like you're good! Your Note 2 will do the digital-to-analog conversion, amplify it, output it via the 3.5mm jack, which you'll then run into the amp, and from the amp into the M100s. Now, it becomes a bit more interesting if your amp is also a DAC-- which yours is. The problem is that I don't believe the E07k has been confirmed to work without the USB Recorder app, which makes it suboptimal for music playback. 

 

As an aside, IMO, part of the improvement in SQ in utilizing an external DAC is that you get an un-amplified output (even when the volume is changed, I believe it is done digitally), so you don't get the reduction in quality that comes from re-amplifying an amplified signal. There are vastly more knowledgeable minds about these matters here than mine, however, so I stand open to correction if it's warranted. (Obviously, if your cans can't run sufficiently from the Note 2s output, then you'd pretty much have to use external amplification, but I'd still wager you'd be better off using both your external DAC and amp. But your M100s should be fine.) 

 

So I'd say if you can get the E07k to work as both a DAC and an amp, you'll be very well off! If you can only use it as an amp, I'd say your chances of experiencing significant improvements in SQ would diminish pretty dramatically. 

 

Again, this is just my opinion, and I don't pretend it's even remotely as knowledgeable as some 'round these parts (lookin' at you, DanBa!! )

Im not very clued up on the digital side of things, However you're pretty much on the ball there.

By using an external DAC you bypass the sources internal amp and DAC,

So you're source basically becomes a Transport. 

The external DAC's etc are usually capable of outputting higher bitrates etc ( I believe )

So you end up with a far cleaner sound and your rig is also going be more optimal :)

But like you said, There are better minds so please correct me if im wrong or right folks lol.

Now, if only it wasn't two weeks away from anyone.

question for DanBa and other android gurus.  I have an sgh-t999 (TMO s3) and wonder if it is worth rootiing it just too get voodosound support?  Does it really improve the sound, and does it work for usb out as well as the headphone jack?

thanks for the guidance.

thanks for answering.  Since it is my phone, i am always a bit leery of changing something that could mess up the phone functionality.  I also thought that the T-Mobile US version did not have the Wolfson chip anyway.  I'd be more interested in a solution that involved a pairing of something like Neutron and the usb enabling of usbaudiorecorder to work together, as it looks like this may be something in-progress.

I do have other portable players, and the phone would just be 'one of the gang' anyway.  This is, however, a fun project And, as much as i would like to maximize performance and minimize 'size/weight', i know that that is not always possible, and I'll chose performance over compactness almost every time.

Okay, about re-amplifying an amplified signal. Here is something that puzzles me.

I have an international T-Mobile Galaxy S3 and an iBasso D-Zero. USB audio out via the supplied OTG cable to the DAC works flawlessly. But changing the volume on the smartphone, changes the volume of the music I hear in my headphones.

How is that possible? The data stream from the smartphone to the DAC is supposed to be all digital, so how can it be amplified by the source?.

There is no way that the D-Zero is picking up an analog signal, sends that through the DAC and from thereon to its amp. USB is never analog, right?

Using the same DAC/AMP with a Macbook Pro or an iPad, the volume of the source component is automatically set to max and locked.

Any ideas? Thanks!

Thanks, NZtechfreak!

EQ control I understand. That is -I think- an alteration made to the outgoing signal made before it is passed to the DAC. EQ information is part and parcel of the data stream, so to say.

If I understand you correctly, volume level can be a component embedded in the digital signal offered to the DAC as well? And it depends on the specific DAC whether it does anything with that part of the data stream?

So it is both a function of the source component (the volume level offered to the DAC is either fixed or continuously variable), and a function of the DAC (is the DAC able to respond to changes made to the volume level offered by the source or does it ignore changes, or is completely blind to those changes)?

Quote:

Originally Posted by maurits 

Okay, about re-amplifying an amplified signal. Here is something that puzzles me.

 

I have an international T-Mobile Galaxy S3 and an iBasso D-Zero. USB audio out via the supplied OTG cable to the DAC works flawlessly. But changing the volume on the smartphone, changes the volume of the music I hear in my headphones.

 

How is that possible? The data stream from the smartphone to the DAC is supposed to be all digital, so how can it be amplified by the source?.

 

There is no way that the D-Zero is picking up an analog signal, sends that through the DAC and from thereon to its amp. USB is never analog, right?

 

Using the same DAC/AMP with a Macbook Pro or an iPad, the volume of the source component is automatically set to max and locked.

 

Any ideas? Thanks!

Quote:

Originally Posted by NZtechfreak 

 

It depends on how the DAC is set up, most DACs I use with my PC also allow PC-side volume and EQ control. Don't worry, your external DAC is doing all the heavy lifting.

Quote:

Originally Posted by maurits 

Thanks, NZtechfreak!

 

EQ control I understand. That is -I think- an alteration made to the outgoing signal made before it is passed to the DAC. EQ information is part and parcel of the data stream, so to say.

 

If I understand you correctly, volume level can be a component embedded in the digital signal offered to the DAC as well? And it depends on the specific DAC whether it does anything with that part of the data stream?

 

So it is both a function of the source component (the volume level offered to the DAC is either fixed or continuously variable), and a function of the DAC (is the DAC able to respond to changes made to the volume level offered by the source or does it ignore changes, or is completely blind to those changes)?

Woah hold on both of you, changing the volume on your phone will cause a loss in SQ and lower the volume levels. Whats happening is digital volume control at 16bits, basically it sends less bits like 15~14 bits, and you lose those other bits in SQ.

The fix is to use 24bit output and the extra is just padded with 0's and then the 0's are truncated. so no loss in SQ. 

But this is not possible in android. SO you MUST keep the phone volume on max.

Quote:

Originally Posted by WiR3D 

 

 

 

 

Woah hold on both of you, changing the volume on your phone will cause a loss in SQ and lower the volume levels. Whats happening is digital volume control at 16bits, basically it sends less bits like 15~14 bits, and you lose those other bits in SQ.

 

The fix is to use 24bit output and the extra is just padded with 0's and then the 0's are truncated. so no loss in SQ. 

 

But this is not possible in android. SO you MUST keep the phone volume on max.

Well that's strange. In my personal experience, if i boost the volume on my phone to max and adjust to a comfortable level on the dac, the lower bass will become distorted. If i lower the volume on the phone a bit and adjust on the dac the problem disappears, no distortion in sub-bass.

Any thoughts on this?

Ex:

Phone volume 10/10 + dac volume 3/10 = Bass distortion
Phone volume 7/10 + dac volume 6/10 = No distortion

Quote:

Originally Posted by CynicalMushroom 

Well that's strange. In my personal experience, if i boost the volume on my phone to max and adjust to a comfortable level on the dac, the lower bass will become distorted. If i lower the volume on the phone a bit and adjust on the dac the problem disappears, no distortion in sub-bass.

Any thoughts on this?

 

Ex:

 

Phone volume 10/10 + dac volume 3/10 = Bass distortion
Phone volume 7/10 + dac volume 6/10 = No distortion

****ty quality song? The loss of bits could be hiding it. 

Because trust me - I'm not wrong about the digital volume control

Don't know how much it helps, but Neutron has a "Preamp Out" setting that supposedly sets the digital gain to zero, avoiding the truncation of bits. Having used the feature, I can tell you it doesn't lock the volume (or at least, I haven't figured out how to do it yet), so it isn't foolproof or anything. But this might address the loss-of-bits issue! :)

EDIT: Also wanted to mention that I've tried the Monoprice USB OTG adapter as well, and it works just fine (PID 9724, here). One advantage is that the micro USB side is a right-angle instead of straight connector, which I find more useful for our needs. Unfortunately it isn't a whole cable, so you'll still need your regular mini-USB cable too, but it's $1.43 and allows me to further my insatiably manly gearcrush on Monoprice stuff. 

Hope this helps somebody!