[vc1187]

On a separate note, beware of the 6BQ7A tubes... for me it's been like playing the lottery.
My Sylvania 6BQ7A has a sputtering noise, and 2 out of 4 Westinghouse 6BQ7As have channel imbalances, with one of them that also occasionally sputters.  The other two are completely silent and fairly balanced. 

 

[Bigsecret]

I would agree that the power tubes make the largest difference, but not by much. When I purchased the EML Mesh 2A3s to replace the stock power tubes there was a noticeable difference. But then, when I replaced the stock rectifier with a U52, it was just as noticeable. And now, I roll in different driver tubes depending on the sound signature of the other tubes. 

 

[listen4joy]

well, since i never had balanced amp i dont understand in balnaced cables so i realize there are
2 3pin XLR or 1 4pin XLR both are balanced. i saw that balanced headphones sold in both routes. 
i wanted to ask what better 1 4pin XLR or 2 3pin XLR?
i saw here the most of the pictures are the one single balanced cable, are the 2x3pin xlr is not popular or its not better like the single 4pin?

 

[Frihed89]

My contention is that all the "upgrades" from the stock tubes do not produce night and day differences from the stock Stratus.

 

[vc1187]

My contention is that all the "upgrades" from the stock tubes do not produce night and day differences from the stock Stratus.

The stock tubes do sound very good with the Stratus, but my ears hear very discernible tube rolling differences when the Stratus is paired with the HD800.  Some tubes I'd consider as clear 'upgrades' and some are clear 'downgrades'.
 
That being said, regardless of tube combination, I found the HD650 to be enjoyable out of the Stratus.

 

[froger]

To me, tube rolling makes lot of difference to some headphones. With the wrong tubes, HD800 can sound unbearably harsh or sleep inducing with the Stratus. With certain tubes combination, I also don't feel like listening to my HE-1000. On the other hand, some headphones don't appeal to me on the Stratus regardless of tubes used.

 

[smitty1110]

  well, since i never had balanced amp i dont understand in balnaced cables so i realize there are
2 3pin XLR or 1 4pin XLR both are balanced. i saw that balanced headphones sold in both routes. 
i wanted to ask what better 1 4pin XLR or 2 3pin XLR?
i saw here the most of the pictures are the one single balanced cable, are the 2x3pin xlr is not popular or its not better like the single 4pin?

For all intents and purposes, dual 3-pin vs 4-pin outputs are identical. In theory the 3rd pin on the 3-pins is for ground, but that's not used with headphones. Any shielding on the cable should be terminated to the ground lug, which grounds through the body of the connector.

 

[taxiq]

My contention is that all the "upgrades" from the stock tubes do not produce night and day differences from the stock Stratus.

In high-end audio I learned long ago that there are no night and day upgrades.   The higher you go the more the focus is on what you are not hearing but ought to be hearing or more likely feeling.  Many mid-fi rigs can produce very enjoyable music but there is much they leave unheard, unfelt.   This is why value propositions tend to be mid-fi issues.  I sometimes think of it as building a mountain of sand.  When we were kids at the beach playing in the sand, it was easy to build a pile two or three feet high, but at some point adding even an inch requires a huge amount of work and a how lot of sand. 
 
Guess, when I was a kid I . .  . .

 

[adamaley]

One man's night and day is another's dusk and night. If you are getting peaky, shrill highs from one tube and switch to a warmer, more agreeable tube, one could jump to the conclusion that it was a night and day improvement - the enjoyment delta may warrant that. Another might not put too much stock into that and feel that it was simply a flavor change....etc....etc...

 

[Frihed89]

To me, tube rolling makes lot of difference to some headphones. With the wrong tubes, HD800 can sound unbearably harsh or sleep inducing with the Stratus. With certain tubes combination, I also don't feel like listening to my HE-1000. On the other hand, some headphones don't appeal to me on the Stratus regardless of tubes used.

Interesting. With the HD800s + AVVT 2A3 + U52 + Mazda 6B7A driver, i heard a dull veiled mid-range and peaky bright treble.  With HD650 I hear what i like with the same tubes.  I wasn't about ready to give up on these tubes,so  I sold the HD800!  Yes, they are warm (and my K701s) are more neutral. But the HD800s are the last set of cans that i will buy without auditioning them first on my own rig!

 

[Frihed89]

  In high-end audio I learned long ago that there are no night and day upgrades.   The higher you go the more the focus is on what you are not hearing but ought to be hearing or more likely feeling.  Many mid-fi rigs can produce very enjoyable music but there is much they leave unheard, unfelt.   This is why value propositions tend to be mid-fi issues.  I sometimes think of it as building a mountain of sand.  When we were kids at the beach playing in the sand, it was easy to build a pile two or three feet high, but at some point adding even an inch requires a huge amount of work and a how lot of sand. 
 
Guess, when I was a kid I . .  . .
 

....learned an important lesson.

 

[Frihed89]

  The stock tubes do sound very good with the Stratus, but my ears hear very discernible tube rolling differences when the Stratus is paired with the HD800.  Some tubes I'd consider as clear 'upgrades' and some are clear 'downgrades'.
 
That being said, regardless of tube combination, I found the HD650 to be enjoyable out of the Stratus.

Yes, they are very versatile, if a little on the warm side.

 

[froger]

Interesting. With the HD800s + AVVT 2A3 + U52 + Mazda 6B7A driver, i heard a dull veiled mid-range and peaky bright treble.  With HD650 I hear what i like with the same tubes.  I wasn't about ready to give up on these tubes,so  I sold the HD800!  Yes, they are warm (and my K701s) are more neutral. But the HD800s are the last set of cans that i will buy without auditioning them first on my own rig!

HD650 and HD800 are quite different sounding,thus what works one is quite unlikely to work for the other. I usually can't enjoy the same tubes I used for HD800 on other cans, especially the darker sounding ones like Audezes and HD650. Of course, others may hear differently or have different taste for sound. That's why I think it is good to tube roll to get the sound you like on your favorite can, just bad for wallet.

 

[Frihed89]

HD650 and HD800 are quite different sounding,thus what works one is quite unlikely to work for the other. I usually can't enjoy the same tubes I used for HD800 on other cans, especially the darker sounding ones like Audezes and HD650. Of course, others may hear differently or have different taste for sound. That's why I think it is good to tube roll to get the sound you like on your favorite can, just bad for wallet.

I know it's not the fashion, but I am not that headphone-centric.  I've only owned two tube headphone amps, a SP MPX3 (with lots of frills) and the Stratus.  I did audition the MPX3 at a show, using HD650s and it sounded wonderful, but it also sounded very good with the K701s.  This was BAD (before Audeze changed the game).  I bought the Stratus, unheard, based on Donald's experience and expertise and have never been disappointed.  In fact, what you say never entered my mind until you said it, and I believe it is true. However, my experience was probably more due to my own sound-preferences, my hearing illness and perhaps a lemon of an HD800, although they did sound much better on an HD SS amp. I do own a pair of first generation LCD-2s, but they are just too dark for me and sound quite different than the pair I auditioned at a show with an early Cavelli hybrid amp, where the darkness was not overly apparent. 
 
I just can't imagine switching out my AVVT tubes.  I do have a number of different 5U4G, VT244, 5U4GB (for other amps/preamps, as well), as well as some RCA 2A3 dual plates (which do make the Stratus sound warmer) and since I am now retired, I may audition some other flagship headphones on my rig to further test your conclusion.  (I have access to the current line of HiFiMan headphones).
 
Then there is the problem that, since i bought the Stratus (original version), I have upgraded the coupling caps and am in the process of upgrading the electrolytic caps on the Stratus and, maybe, a few resistors - all with Audio Note (UK) components.
 
Thanks.

 

[punit]

 On the other hand, some headphones don't appeal to me on the Stratus regardless of tubes used.

Just out of curiosity which HP's didn't appeal to you on the Stratus ? The only HP which didn't appeal to me on the Stratus was HE 6 (which is my favourite HP btw & I find it quite ironic that my Fav HP doesn't get along well with my fav amp).  I have tried  around 15 HP's on the stratus and all of them sound either good or amazing.