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DNA Stratus 2A3 amplifier - first impressions - Page 8

post #106 of 1678
Thread Starter 

I just returned from a week abroad to find a couple of pm's asking my Stratus tube recommendations for the $$ conscious buyer. Sorry it wasn't clear.

 

 

I would first recommend replacing the Sovtek 6N1P driver with a NOS RCA 6BQ7a at $10-20. Mine is cryo'd, a treatment I have always found beneficial. Second, the rectifier 5U4G at $20-90. Last the 2A3s. My top choice to date is the EML meshplates, after >160hrs burn-in, for $555 (+s/h). However, the least expensive option might be the NOS RCA or Tung-Sol blackplates, which are still available at audiotubes for $225-250. A competing high-value choice might be the Sophia globe mesh for $235-299, depending on options - I have only heard their top Princess model ($325-375+s/h), so this is a guess, but my guess is that their lowest price 2A3 would give you presence and sweetness with more clarity than the stock Sovtek or the NOS tubes, but not as much clarity as the Princess or the EML.

 

If anyone has more comments on tube recommendations, please chime in.

 

and madbull, have you had a chance to listen to your new Stratus yet?

 

 

post #107 of 1678

I second the RCA 6BQ7a recommendation. I found one in my stash and prefer it to the stock tube. I haven't experimented enough with the other tubes to comment.

post #108 of 1678

The stock 2A3s are Shuguang 2A3Bs. I prefer them over the Sovtek.

Quote:
Originally Posted by budx3385 View Post
their lowest price 2A3 would give you presence and sweetness with more clarity than the stock Sovtek
post #109 of 1678
Thread Starter 
Quote:
Originally Posted by Donald North View Post

The stock 2A3s are Shuguang 2A3Bs. I prefer them over the Sovtek.

Yup, and I wrote that in an earlier post, too. Thanks, Donald - keep me on my toes here! That's one reason the Shuguang Treasure Nature Sound 2A3 pair are here to try.

 

But the EML 2A3-S solid plate tubes arrived in my absence as well, and I quickly rolled them in behind the EML 2A3-M meshplates today, and after only 6 hrs of use (in two 3 hr periods) they are simply INCREDIBLE. Soo lifelike, spot-on tone, full timbre, real powerful authority, and 3-dimensional depth to every already-large and solid voice. The top spot on my tube list in post #106 is about to change .....

 

 

EDIT 6-26-12

Sorry, I meant to say "The top spot on my tube list in post #106 may be about to change. But, they need a lot more burn-in ....."


Edited by budx3385 - 6/29/12 at 9:31pm
post #110 of 1678

My speaker amps use parallel single ended 2A3s and have seriously considered ordering a quad set of the EML 2A3 solid plates to try in them. From your description above I see a tube purchase in my future... smily_headphones1.gif

post #111 of 1678
Quote:
Originally Posted by budx3385 View Post

I just returned from a week abroad to find a couple of pm's asking my Stratus tube recommendations for the $$ conscious buyer. Sorry it wasn't clear.

 

 

I would first recommend replacing the Sovtek 6N1P driver with a NOS RCA 6BQ7a at $10-20. Mine is cryo'd, a treatment I have always found beneficial. Second, the rectifier 5U4G at $20-90. Last the 2A3s. My top choice to date is the EML meshplates, after >160hrs burn-in, for $555 (+s/h). However, the least expensive option might be the NOS RCA or Tung-Sol blackplates, which are still available at audiotubes for $225-250. A competing high-value choice might be the Sophia globe mesh for $235-299, depending on options - I have only heard their top Princess model ($325-375+s/h), so this is a guess, but my guess is that their lowest price 2A3 would give you presence and sweetness with more clarity than the stock Sovtek or the NOS tubes, but not as much clarity as the Princess or the EML.

 

If anyone has more comments on tube recommendations, please chime in.

 

and madbull, have you had a chance to listen to your new Stratus yet?

 

 

 

Not yet, and unfortunately it's gonna take a long time :(

post #112 of 1678
Thread Starter 
Quote:
Originally Posted by madbull View Post

 

Not yet, and unfortunately it's gonna take a long time :(

 

awwwww

that IS sad

 

oh well

 

The new EML solid plates have ~15-20 hrs, and the 3D effect is filling out - at first it felt like flat images at different depths / locations, and now the images are no longer flat, they are solid and shaped. WOW. I still feel like there is a bit more emotion to be had, so I will keep burning, but so far these tubes on the Stratus are becoming more and more INCREDIBLE, like I said earlier.

 

Using the HD800, the imaging is truly amazing. On a CD by Fretwork, the separate instruments / voices are large and coherent and so distinguishable that I can now easily follow the fugal figures as they are passed around between instruments in these Fantasias that Henry Purcell wrote (at the age of 15 or so).

post #113 of 1678
Thread Starter 

UPDATE 6-29-12

The EML solidplate 2A3-S output tubes have > 60 hrs now, so I made a direct comparison with the well-burned-in EML meshplates, using 5 different genre's from JRMC. To my ears, the solidplates have the most incredible 3D imaging, but the meshplates have breathtaking presence, which I can feel on every note. Both have fast, powerful, detailed, clean and authoritative presentations that make the Stratus an outstanding headphone amp, with every headphone I have tried.

 

The Audeze LCD-3 arrived yesterday on loan from TheCableCo. Using either its single-ended 1/4" TRS cable (good) or a DHC RSS or RSC Complement balanced cable (better) on the Stratus, the SQ is quite beautiful, with deeper spatial perspective than the T1 or HD800. I am looking forward to hearing this combination again when the solidplates have > 150 hrs burn-in; I will be most interested in seeing whether the different spatial perspective of the LCD-3 will overcome its less convincing tonal perspective.

 

I also tried the HE-6 again. It has > 300 hrs burn-in now, and it has really opened up. Detailed, realistic and 2D4 SQ driven by the Odyssey Cyclops (100 wpc ss), it sounds nearly as good now on the Stratus (1.8 wpc), with the volume control turned up to 5 - 7. It would be difficult to choose between the LCD-3 and the HE-6 using the Stratus at this time. I will check this again, too, when the solidplates are more burned-in, but at the moment I think the HE-6 still sounds better with higher power. Driven by the Cyclops, I feel the tonality of the HE-6 is more convincingly realistic than that of the LCD-3.

 

IMHO.

beyersmile.png

post #114 of 1678
Just traded my HD800's for a pair of LCD-3's, so I'm looking forward to trying them on the Stratus!!
post #115 of 1678
Quote:
Originally Posted by budx3385 View Post

Yup, and I wrote that in an earlier post, too. Thanks, Donald - keep me on my toes here! That's one reason the Shuguang Treasure Nature Sound 2A3 pair are here to try.

 

But the EML 2A3-S solid plate tubes arrived in my absence as well, and I quickly rolled them in behind the EML 2A3-M meshplates today, and after only 6 hrs of use (in two 3 hr periods) they are simply INCREDIBLE. Soo lifelike, spot-on tone, full timbre, real powerful authority, and 3-dimensional depth to every already-large and solid voice. The top spot on my tube list in post #106 is about to change .....

 

 

EDIT 6-26-12

Sorry, I meant to say "The top spot on my tube list in post #106 may be about to change. But, they need a lot more burn-in ....."

Most people who have tried these prefer the solid plate.  The sound is, well, more "solid".  The only reason I don't have a pair is because I have a pair of AVVTs.  However, they are very, very hard to find and my source was just pure luck.

post #116 of 1678
Thread Starter 
Quote:
Originally Posted by Donald North View Post

My speaker amps use parallel single ended 2A3s and have seriously considered ordering a quad set of the EML 2A3 solid plates to try in them. From your description above I see a tube purchase in my future... smily_headphones1.gif

 

 

OK, Donald. I have been particularly careful, in light of your very special interest. And now I am certain --- the EML 2A3-S solid plate tubes are definitely my top recommendation. I hope I will get to hear them driving your speakers someday!

 

Mine have > 160 hrs now, mostly 4-6 hr runs, all music, with at least 1 hr cool down, so they have been burned in with adherence to EML's suggestion. I listened to several different tracks from different CDs each morning, and the improvement in SQ was obvious each day. Using these tubes with a cryo'd NOS 5U4A rectifier and a cryo'd NOS RCA 6BQ7a, the Stratus produces top-of-the-line sound quality on my well-burned-in (>400 hrs) HE-6 on a solid silver cable or my even-further-burned-in T1 on a rectangular solid copper cable.

 

"Solid", yes indeed, with 3D layers, full extension, utter transparency, micro-detail, fast, dynamic, powerful and very EMOTIONAL.

Music 2D4. smile.gif

 

and Frihed89, if you ever see another pair of AVVT 2A3s for sale, please grab them for me (I will gladly pay premium) or pm me asap. Thank you very much for your recommendations!

 

 

To my ears, the LCD-3 did not produce a satisfyingly realistic tonal palette. It had gorgeous coherence with clarity equal to that of the HE-6 or T1. Obviously, YMMV.

 

The Shuguang Treasure Nature Sound 2A3 tubes are here, untested, but I think I will simply enjoy my Stratus for now. And I hope madbull and santacore will begin sharing their listening experiences with the Stratus soon !!!!!!!!!


Edited by budx3385 - 7/9/12 at 12:33pm
post #117 of 1678

The only person who has a large stash of top quality ones is Dennis Fraker, the proprietor of Serious Stereo, somewhere in Montana.  But I doubt if he sells them without am amp attached.  You could write him.  The price may shock you, even if he is willing to part with a pair.

post #118 of 1678

For you bravehearts, Woo is selling adapters for the 596 rectifier, which is a replacement for the 5U4G in the WA22.  I don't know much about the 596, but I think it comes from the late 1920s!  Do not use this tube unless you a) know the electrical characteristics of this tube (I could find none) and b) consulted with Donald (for whom this tube may also be an unknown).  In general, you do NOT want to use a rectifier that Donald is not familiar and comfortable with.  At best-worst, it may make no sound and at worst-worst it may take out your power supply.

post #119 of 1678
Thread Starter 
Quote:
Originally Posted by Frihed89 View Post

The only person who has a large stash of top quality ones is Dennis Fraker, the proprietor of Serious Stereo, somewhere in Montana.  But I doubt if he sells them without am amp attached.  You could write him.  The price may shock you, even if he is willing to part with a pair.

 

Frihed89, many thanks again! I am on the trail.

post #120 of 1678

I would be suspicious and cautious towards the AVVT 2A3 meshplates. A couple years ago I bought a NOS quad set in beautiful blue glass with the intention of using them in my speaker amps. Before installation I tested them on my Amplitrex and found that they drew substantially higher plate current than the textbook 2A3. In a normal amplifier with auto (self) bias, the tubes would been burnt through quickly. I ended up selling them with the disclosure that they measured different from normal 2A3s and should be used in an amplifier with fixed (adjustable) bias.
 

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