[c64]

For me the 650 sound very similar to the x1 just not as full bodied as obviously they need an OTL amp.

 

[HungryPanda]

DX80 via Topping NX2 does the trick or my PC via sanskrit 6th Gen dac to Little Dot MKII (with voskhod tubes) and they are incredible

 

[Koolpep]

  For me the 650 sound very similar to the x1 just not as full bodied as obviously they need an OTL amp.

That's good for you then, since the X1 is easier to drive and doesn't gain much from better amps. You can save money. 
 
I loved my C64 by the way.

 

[Letmebefrank]

The 650s sound great on the vali 2 with a jj e88cc gold pin tube. Not thin by any means.

 

[DavidA]

  For me the 650 sound very similar to the x1 just not as full bodied as obviously they need an OTL amp.

Did you know before you got the HD-650 that it is a little amp picky?  Not as bad as the HD-800 but most will put some though in to the rest of their audio chain before buying the HD-650, and also the HD-600, more so if you are on this thread and have read a few pages of post asking what is a good amp for them from many others. which comes up quite often.
 
But as @Koolpep noted if the X1 works for you then you can save money.

 

[raybone0566]

Once you have the right components in place the 650's are sublime. It's funny every few days the amp issue pops up.

 

[SirMarc]

The cheapest way to get the 650's sounding good is a vintage 70's receiver or integrated amp. The added bonus is multiple inputs, a phono stage, can drive speakers and they look cool. The downsides are they're old, so a bit of a crapshoot on reliability and they're big, so space could be an issue

 

[rigo]

The cheapest way to get the 650's sounding good is a vintage 70's receiver or integrated amp. The added bonus is multiple inputs, a phono stage, can drive speakers and they look cool. The downsides are they're old, so a bit of a crapshoot on reliability and they're big, so space could be an issue

 
My dad just offered to give me one of his vintage receivers - a Pioneer or Yamaha.  I don't remember the models but they look great and are in great condition.  Eager to try out the 650s once I set it up.  

 

[Tuneslover]

The 650s sound great on the vali 2 with a jj e88cc gold pin tube. Not thin by any means.

It's ok but not great sounding, in my opinion. I find the HD650 just a bit underwhelming sounding withe Vali2. I prefer the HD598/Vali2 synergy better, but then I like high frequency detail.

 

[Tuneslover]

The cheapest way to get the 650's sounding good is a vintage 70's receiver or integrated amp. The added bonus is multiple inputs, a phono stage, can drive speakers and they look cool. The downsides are they're old, so a bit of a crapshoot on reliability and they're big, so space could be an issue

I agree but would also suggest a good integrated amp too. My NAD C 326BEE makes my HD650's sing.

 

[Krutsch]

As the boy from Matrix would say...

 
Ha ha... that's awesome. Stealing that one.
 

 

[mysticstryk]

  For me the 650 sound very similar to the x1 just not as full bodied as obviously they need an OTL amp.

 
Check out the Fostex Thx00 if you want a more refined, bassy signature.  Would be a solid upgrade choice from your X1.
 

   
Ha ha... that's awesome. Stealing that one.
 

 
Haha, have at it.  I'm sure we will get use out of it again. 

 

[audiojun]

I just made a meme that applies to audiophiles, first world problems.
 

 

[silverbox]

You can't just make a meme. That looks like a pic with some text on it.

 

[SirMarc]

My dad just offered to give me one of his vintage receivers - a Pioneer or Yamaha.  I don't remember the models but they look great and are in great condition.  Eager to try out the 650s once I set it up.  

You will probably be pleasantly surprised. Once you get the model numbers, head over to the vintage receiver and integrated thread. There's a bunch of cool guys with a lot of knowledge over there. Be careful though, its another deep rabbit hole lol