[arnyk]

   
It isn't just about loudness, it is about speaker control and clarity. Unpowered it just doesn't sound as good. Sorry if I am doing a bad job explaining. When I went from my ancient Pocket Amp V2 to Gilmore Lite it was night and day.
 
I am happy to hear the 650 drivers are more efficient. The Asgard 2 has a 15 day money back guarantee so if I find the 650 sufficiently good without it I might just return it. 

 
Audible differences in what some call speaker control, and clarity are predominately about frequency response, IOW loudness.
 
The most valuable upgrade that a headphone amp generally provides is firstly low source impedance.  The ability to produce > 1 vrms into a headphone load runs a close second.
 
This is because most headphone jacks on desktops and laptops provide a source impedance of 50-75 ohms which is inadequate for headphones whose impedance bottoms out at less than a tenth or fifth of that.  
 
Other than specialized hardware, most portable digital players, cell phones, smart phones, and tablets as well as laptops and desktops can't produce more than 1 volt into any load without outboard assistance. Many are inherently limited to as little as half that.

 

[Svperstar]

    And make sure the 650 drivers are in phase when you install them.

 
I'm going to assume when you said this you meant make sure I don't plug the cables in backwards?

 

[mindbomb]

   
I'm going to assume when you said this you meant make sure I don't plug the cables in backwards?

 
yea. that could explain why they don't sound right.

 

[Svperstar]

   
yea. that could explain why they don't sound right.

 
I have my 580s plugged in with the L and R on the correct sides and with the letter facing outwards. I wasn't aware people had trouble figuring this out.

 

[mindbomb]

i meant the wires from the driver to the headphone cable connector, but now I think it comes pre-assembled so it's not possible for that to be reversed. 

 

[Svperstar]

  i meant the wires from the driver to the headphone cable connector, but now I think it comes pre-assembled so it's not possible for that to be reversed. 

 
Yes it does. These 10 year old 580s drivers are done. I have taken them apart a few times to clean them but they are dusty and old and both have developed small tears in the actual driver and are covered in a small film of dust. In addition a channel imbalance has developed which I compensate for by moving the balance slightly to the right.
 
Replacement 580/600 drivers are $72 each and 650 drivers are $50 yeah so it was a no brainer. I think from this point forward I am going to make a point of buying new drivers every 5 years.

 

[cjl]

   
It isn't just about loudness, it is about speaker control and clarity. Unpowered it just doesn't sound as good. Sorry if I am doing a bad job explaining. When I went from my ancient Pocket Amp V2 to Gilmore Lite it was night and day.
 
I am happy to hear the 650 drivers are more efficient. The Asgard 2 has a 15 day money back guarantee so if I find the 650 sufficiently good without it I might just return it. 

Actually, power is just about loudness. All that a more powerful amp gives you is the ability to go louder before distorting. If you can already go loud enough, and your amp isn't distorting, you won't gain anything from a more powerful amp.