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Sofia Electric Blue 6SN7

Just received a pair of these this morning and to say I'm delighted is an understatement.At $99 per tube I was so hoping it wouldn't turn out to be a mistake.Big sigh of relief and a bigger smile.After fooling around with various tubes,footers,and cables trying to clear up what I was hearing as a congested midrange when there were multiple instruments,this tube has done it.

I replaced the Sylvania 'bad boy' driver tube in my Aric Audio Transcend amp just to get a feel for the sound before removing the bazillion tiny screws in the LTA MZ2 to try them there.Well it's staying right where it is in the amp.The mids cleaned up immediately and the entire presentation seems faster and even more dynamic.The vocals retain their sweetness with no excess sibilance.I recently tried a new EH in that position and also in the MZ2 which gave me the clarity but they were relentlessly hyper detailed.
I have read some cautionary tales about Sofia tube's reliability but they mostly involved power tubes, so fingers crossed.I'll update if any problems surface.So far my perfect tube compliment is one Sofia blue 6SN7,two Sylvania 6SN7,four (new)Tung Sol KT150 power tubes in the amp.The pre has two 12AT7 Sylvanias and two (new)Tung Sol 6SN7.
128x128jtcf
brownsfan
1,508 posts
 
@jtcf  Thanks.  I've been through the drill before with the M-60s, and yes, it takes a bit of time, but I have a pretty good feel for what the amps like in terms of 6SN7 attributes at each of the 4 positions, so its not quite as bad as trying to work my way through all of the 256 possible variations.  In actual fact, this comes down to a yes/no on two of the 4 positions, with the new Sophias potentially replacing the RCA grey glass tubes.  Those two positions have the greatest impact on sonics.  The third position (back, center, one the MK 3.3s) really seems to benefit from the bad boys.  Assuming I like what I hear with Sophias in the two most impactful position, it really comes down to getting a quick A/B  on the bad boys vs. two other Sylvanias that I have on hand.  Tube rolling in the 4th position (front tube), which requires GTA or GTBs, has less impact on sonics.  I always roll that position after I have the other 3 established.  I can probably get this done in 3 or 4 listening sessions, so it is really not all that laborious.  
jtcf's avatar
jtcf OP
1,620 posts
 
An update about these tubes after almost a year of daily use:They seem to have lost the beautiful tone I was so thrilled with initially.The vocals especially became increasingly harsh.Of course I didn't suspect the Sofias and began switching out other tubes with no luck.Yesterday I swapped in a Sylvania in the amp and it was instant relief.Dang.Next were the two in the pre.
So it seems they were good for about nine months/-500 hrs and began to decline slowly.
The Sylvanias are ok but a little congested in the midrange.I've got three pairs of different NOS tubes on the way to try now.
shkong78's avatar
shkong78
1,485 posts
 
Hello Op

What three pairs of Nos 6sn7 tube did you get?

My bet for best value for performance is RCA, Sylvania, Raytheon vt 231 made in 1940's..

if you search Ebay you may get a pair around 100$.

Rca sounds warm and lush while Syl sound transparent with excellent details.

Raytheon is midway between Rca and Syl.

Thomas
cbedry66
4 posts
 
Hey there,

Ive been running a "Grade A" Sophia Electric 6sn7 Blue glass in my Icon Audio PS3 MK II for about the past 7 months. It sounds great! In my opinion it sounds better than the David Shaw CV 181 "HIFI Vale" that came with the unit. However, just yesterday, it failed me. One of the triodes crap  the bed, the right channel in this case. I got a loud pop and then there was next to no audio passing through the right channel. it was at this point that i had also noticed microphonics from it. So a nearly $200 tube for 7 months that could have damaged other components in my rig while it was at it. Unfortunately, id say in my experience here, they are unreliable. I emailed Sophia Electric and explained this to them and asked them for an exchange for a new tube or a discount on a new one or something to help me out here even though its out of the stock 30 day warranty; well see what they have to say, ill keep you guys posted if anyone is interested.
peterh_nz
6 posts
 
I was thinking about buying a pair of these, so I'm definitely interested in what Sophia Electric had to say.  I've been using pairs of both their (so called) Mesh Plate 274B's and Royal Princess 300B's for the last few years and no problems. But I'm about to switch to some NOS STC (~1962) 300B's, and they make the Royal Princess' seem really cheap!  I have some NOS Mullard ECC32's, but I'd much rather save them.
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