[StanD]

   
So I found this Anandtech audio test, and they say: "In our test data, the most powerful phone was the iPhone 5, at 32.46 mW of power. Next is the Nexus 5 at 22.24 mW, though we can’t drive it that high. Then the Note 3 at 11.81 mW and finally the Galaxy S4 at 3.895 mW."
 
They don't say what load those numbers are into, but just looking at those relative numbers, our different impressions make sense: The Nexus 5 has twice the output power of a Note 3, and more than 5x the power of a Galaxy S4.  So I take back what I said: If you're using a Samsung phone with the HD600, you might very well see a significant, not merely audible, difference with the Magni.
 
I still quibble a bit at "night and day" -- nothing you can do is going to give you the same totally clear, radically different sound signature you'd get from a different headphone -- but yeah, you will almost certainly be much happier with the HD600 with an external amp, rather than straight out of a Samsung phone.

This article states that the tests were done using Apple Earpods, which according to Apple is 23 Ohms so there is a small disconnect to the 32 Ohms examples I'll give below.
Going by the numbers you gave, just 1.5W (Uber at 32 Ohms) is 16.6 dB more power than the iPhone 5, which is significant. 1.5W compared to the Note 3 is 21 dB more power.  One should also be aware that our hearing's FR varies with loudness, so at lower volume our perception of bass diminshes as does treble to a lesser degree. All of these power levels will be much lower at 300 Ohms where the power supply rails of a phone pale in comparison to the Magni. The Magni 2 Uber has +/- 16V power rails and 320 mW at 300 Ohms which is more like in the domain of the HD600. Reverse engineering the numbers for the iPhone's power at 23 Ohms, gives 0.864 V which gives 2.5 mW at 300 Ohms. OK, that's some fiddling to get to the numbers.
If I'm right, that gives the Magni a 21 dB advantage at 300 Ohms.

 

[LaPierre]

   
i think thats just how hd600 sounds. it's not bright. have you listen to something like grado for a change? even the $100 one. it has a completely diff signature with your hd600. with better amp you will get better bass and more power to drive the hd600 but the essence of the sound is still there. i think hd600 sounds natural.
 
i maybe mix up neutral and natural here, but yeah. it's not bright. maybe thats why its not exciting to you....?

There's no way <50mw from a phone will power the 300 ohm HD600. That's a lot less power at 300 ohms, not to mention its a portable amp with inferior architecture so it can't provide nearly enough voltage. A dedicated amp will make a huge difference, it'll defiinitely tighten up the bass. HD600 is fairly close to neutral with a slight, slight bass bump.

 

[LaPierre]

I really want to try the SR80, I've been so curious about the grado signature for awhile T.T

 

[mkozlows]

  If I'm right, that gives the Magni a 21 dB advantage at 300 Ohms.

Sure -- but I never listen at anything like max volume, even out of the phone, on the HD650. 
 
There's no question that the Magni is better, technically and audibly, than a phone into HD600/HD650 phones. All we're quibbling about is the magnitude of the difference. I can say from experience (with a different but similar amp) that it's a subtle change from the Nexus 5, but it sure is plausible that it could be unsubtle from a phone that has 1/5 the power, like the GS4 does, right?

 

[rovopio]

  I really want to try the SR80, I've been so curious about the grado signature for awhile T.T

 
the sr80e clamp force is far tighter than sr60i. or maybe my sr60i is just old

 

[StanD]

  Sure -- but I never listen at anything like max volume, even out of the phone, on the HD650. 
 
There's no question that the Magni is better, technically and audibly, than a phone into HD600/HD650 phones. All we're quibbling about is the magnitude of the difference. I can say from experience (with a different but similar amp) that it's a subtle change from the Nexus 5, but it sure is plausible that it could be unsubtle from a phone that has 1/5 the power, like the GS4 does, right?

One word to consider is headroom. My Asgard 2 or Magni 1 kills any smartphone whether with my HD600 or HD-500.

 

[yearsofwisdom]

   
So I found this Anandtech audio test, and they say: "In our test data, the most powerful phone was the iPhone 5, at 32.46 mW of power. Next is the Nexus 5 at 22.24 mW, though we can’t drive it that high. Then the Note 3 at 11.81 mW and finally the Galaxy S4 at 3.895 mW."
 
They don't say what load those numbers are into, but just looking at those relative numbers, our different impressions make sense: The Nexus 5 has twice the output power of a Note 3, and more than 5x the power of a Galaxy S4.  So I take back what I said: If you're using a Samsung phone with the HD600, you might very well see a significant, not merely audible, difference with the Magni.
 
I still quibble a bit at "night and day" -- nothing you can do is going to give you the same totally clear, radically different sound signature you'd get from a different headphone -- but yeah, you will almost certainly be much happier with the HD600 with an external amp, rather than straight out of a Samsung phone.

Funny, I'm using exactly the S4! This is great to hear. I'll definitely pick up the Stack then.

 

[StanD]

  Funny, I'm using exactly the S4! This is great to hear. I'll definitely pick up the Stack then.

Trust me, you'll be in for a treat. Just make sure that if you get a Modi, find out if you'll need to get a powered USB Hub. Whether I used my S3, or now use my Note3 or iPod Touch 5G with my Bifrost Uber USB, I need the Hub. I got the powered Hub that Schiit recommended from Amazon, it has a power switch that kills the USB connection entirely so your phone is no longer connected, great feature.
http://www.amazon.com/gp/product/B004OBZ088

 

[yearsofwisdom]

  Trust me, you'll be in for a treat. Just make sure that if you get a Modi, find out if you'll need to get a powered USB Hub. Whether I used my S3, or now use my Note3 or iPod Touch 5G with my Bifrost Uber USB, I need the Hub. I got the powered Hub that Schiit recommended from Amazon, it has a power switch that kills the USB connection entirely so your phone is no longer connected, great feature.
http://www.amazon.com/gp/product/B004OBZ088

Interesting. So I can actually use the Stack with my phone? How does that work? Total noob if you haven't noticed haha

 

[TheDragonGuy]

I already happen to have the cable even tho I don't plan to use it. Its called a 3.5mm to RCA. the 3.5mm goes into your phone and the other end has 2 RCA plugs which plug into the dac.
http://www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021815&p_id=5598&seq=1&format=2

 

[yearsofwisdom]

  I already happen to have the cable even tho I don't plan to use it. Its called a 3.5mm to RCA. the 3.5mm goes into your phone and the other end has 2 RCA plugs which plug into the dac.
http://www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021815&p_id=5598&seq=1&format=2

Okay cool! What's this have to do with StanD's USB hub? How's his setup work?

 

[TheDragonGuy]

http://schiit.com/guides/getting-connected

 

[mkozlows]

I already happen to have the cable even tho I don't plan to use it. Its called a 3.5mm to RCA. the 3.5mm goes into your phone and the other end has 2 RCA plugs which plug into the dac.
http://www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021815&p_id=5598&seq=1&format=2

That will go to an amp, not a DAC.

 

[StanD]

Gentlemen, you connect your Android phone to the DAC (Modi 2) using an OTG USB cable, assuming your phone is compatible with USB Audio out, A current iPhone requires a Lightning CCK cable, an earlier one might work with the 30 pin CCK. You might have to use a powered USB Hub in between as the DAC might draw more power from your phone than it can deliver, just get one, I provided a link to the one I got a few posts back.
I have used a Samsung Galaxy S3, Note 3 and an Apple iPod Touch 5G with DACs. My Bifrost Uber USB DAC required a powered Hub.
Below is a link to a very lengthy thread on using Android devices. After skimming the beginging, you might want to skip towards the end, There's a repeated page with links to download files listing compatible devices.
http://www.head-fi.org/t/595071/android-phones-and-usb-dacs
 
Of course you connect your DAC to Amp using RCA cables.

 

[clientsiman]

So If I want to use the stack with my passive speakers is this the right configuration?  
 
USB cable->MODI 2 UBER->RCA Cable->MAGNI 2 UBER->RCA Cables->Passive speaker amp. If I have understood it correctly I can use the volume from MAGNI to control the volume of the speaker when my headphones are not connected.
 
One more question, My passive speaker amp is also a DAC ( SMSL SAD-25). By using the RCA Cable to connect it with MAGNI 2 UBER I would be able to use the MODI 2 UBER as my DAC and bypass the inferior DAC that SAD-25 has?