DNA Stratus 2A3 amplifier - first impressions - Page 27

I use the HD800 with Sophia Princess. The stock tubes make the Stratus sound very good as is, the Sophia's add clarity, soundstage, more air around vocals, overall more coherent. 

I believe the choice of 2A3 is everything with this amp.  Incredible variation in staging, treble response, airiness, bass clarity, resolution, punch, everything.  My current favorites are NOS Ken Rad dual boxplates.  I have a pair of NOS Sylvania dual monoplates on order that may top those according to what I've read. The RCA black s-plates are very nice too, very neutral and balanced.  The EML meshplates add a kind of *humidity* as we've been discussing that is quite unique and pleasing.  I have not yet tried the Sophias.  Next I will be experimenting with rectifier variants.  So far the EML 5U4G is better tonally than the EML 274B but both are topped by a simple NOS RCA 5U4G for resolution and balance.  The EMLs add a little too much coloration to the bottom end for my taste, although they are enjoyable for other reasons - like slam of sub bass.  I will report back once a few more arrive. 

budx3385, on your recommendation I have ordered the Sophias.  I recently modded my HD800s and have fallen in love with them again so I want to give this combination a try.  The Sylvania 2A3s fell through, by the way.  NOS matched pairs are getting harder to find.  The supply really is drying up globally.  All the more reason to find the current manufacturers that are good.  I'll report back about the rectifiers.
 

Oh, and when I said the choice of 2A3 is everything with this amp, I didn't mean to imply it is the single largest determining factor of the over all sound of the amp. The Jensen caps and the output transformers are arguably a larger part of the "Stratus sound."  But since those are not easily or casually rolled, I was merely referring to those aspects of the sound that we can control.  So, in other words, the choice of 2A3 matters more than the rectifier, more than the input tube and more than the fuse.  Power cord has made a large difference - but I know not everyone feels this way, so I usually leave that out...

When developing the Stratus, a lot of time and listening was spent auditioning different components, from the coupling capacitors, plate and grid load resistors, cathode bypass capacitors, etc., to arrive at what I thought was the best sounding balance to me.

Quote:

Originally Posted by fejnomit 

Oh, and when I said the choice of 2A3 is everything with this amp, I didn't mean to imply it is the single largest determining factor of the over all sound of the amp. The Jensen caps and the output transformers are arguably a larger part of the "Stratus sound."  But since those are not easily or casually rolled, I was merely referring to those aspects of the sound that we can control.  So, in other words, the choice of 2A3 matters more than the rectifier, more than the input tube and more than the fuse.  Power cord has made a large difference - but I know not everyone feels this way, so I usually leave that out...

Interested to know how you compare components? do you run two units side by side and do quick A/B? which headphone do you normally use?

With the Stratus + HD800 combo, what DAC seems to compliment this the most?  

I would listen to the amplifier from a few days to a few weeks with a particular set of components, familiarizing myself with the overall sound, then switch one and note the differences heard. If it was an improvement, I would then listen and get acclimated with the sound and then change a different component, again noting the difference. In my experience with quick A/B comparisons, you can hear gross differences but not so easily the subtler differences. I used the K1000, DT770 Pro 80, DT931, K240DF, and even some Triports. I also had a couple friends listen and share their observations, who used HD800 and LCD2.

Quote:

Originally Posted by zenpunk 

Interested to know how you compare components? do you run two units side by side and do quick A/B? which headphone do you normally use?

Well, your method has surely paid off.  If I didn't already love the *stock* sound you have achieved, Donald, all the rolling in the world wouldn't make a difference.

Bravo on having great ears and great patience.  Of course the circuit is a large part of the sound as well - but again, not something we would want to mess with aftermarket.

And it terms of DAC, I have been using my Stratus with my RAM-modded W4S DAC2 with stunning results.  The DAC has been outfitted with a Silver Rock output transformer and Audio Consulting silver wire and the level of resolution is outstanding.  Fed into the Stratus, it is highly recommended.

Quote:

Originally Posted by fejnomit 

budx3385, on your recommendation I have ordered the Sophias.  I recently modded my HD800s and have fallen in love with them again so I want to give this combination a try.  The Sylvania 2A3s fell through, by the way.  NOS matched pairs are getting harder to find.  The supply really is drying up globally.  All the more reason to find the current manufacturers that are good.  I'll report back about the rectifiers.
 

Congrats on the Sophia's, I'll be interested to hear your impressions vs the other 2a3's. What mod did you do to your HD800's and what changed you mind on them?

Quote:

Originally Posted by Donald North 

I would listen to the amplifier from a few days to a few weeks with a particular set of components, familiarizing myself with the overall sound, then switch one and note the differences heard. If it was an improvement, I would then listen and get acclimated with the sound and then change a different component, again noting the difference. In my experience with quick A/B comparisons, you can hear gross differences but not so easily the subtler differences. I used the K1000, DT770 Pro 80, DT931, K240DF, and even some Triports. I also had a couple friends listen and share their observations, who used HD800 and LCD2.

Sensational advice, Donald, and I believe that same advice is relevant to system matching in general. We often talk that talk here on Head-Fi, but how often do we walk the walk ?  ;)

Unfortunately for my day job I walk that walk far too often, my friend - trying new combos of tubes, phones and cables when I should be working...

It's all about the endless shuffle toward that ever-shifting perfection...

Quote:

Originally Posted by fejnomit 

Unfortunately for my day job I walk that walk far too often, my friend - trying new combos of tubes, phones and cables when I should be working...

It's all about the endless shuffle toward that ever-shifting perfection...

I suspect that you and I are walking in very different directions if that is the case - I was referring to Donald's suggestion that we make a single change and settle on that combination for weeks before changing anything else. As far as your job goes, I'd count my blessings - 2013 could prove to be a very interesting year for all of us.