Shootout of Nos 6sn7 tubes

Interesting thread!I recently found a seller on Esty and ordered a few GE,Tung Sol,RCA to try for the input tube in my amp.All short bottles, black plates,black bases.Those RCAs are really dynamic with excellent textured bass.A nice surprise:-)The TSs have a wonderful midrange but not much detail top or bottom.The GEs are both lush and detailed,really nice.These all averaged around $20 apiece so not too expensive to experiment with.

I needed to replace the Sofia Blue which I really liked for almost a year.They aren't noisy or anything,but somehow lost their tone and sounded flat.Just not worth the price if they have to be replaced often.

Black Sabbath and the 1578s seem to get along well. 

@ jtcf

If you are bass or soundstage freak then you  may go for 1578 Melz.

Ken rad vt 231 is also pretty good choice all around.

If you care about details or transparency, then go for Sylvania vt231.

For lush and warm sound, go for RCA vt231.

Raytheon Vt231 is also good choice midway between Syl and Rca.

I am back to RCA vt231 in Line Magnetic 508 amp which make me comfortable with lush and warm sound but also with nice bass.


f I want explosive bass or widest and deepest soundstage, I play 1578 Melz.

Ken rad vt 231 has nice bass with more air than 1578

If I want utmost details , then I play Sylvania vt231.

If i want see through transparency, then I play TS bgrp

For lush and warm sound, I would go for RCA vt231.

Raytheon Vt231 is also good choice midway between Syl and Rca.

With taking turns on 6 sets of 6sn7 tubes, it is like having 6 different set of preamp.

I had done second sets of shootout

"Autumn Leaves" by Eva Cassidy
""Caravan" in the Still Harry Album.
’" You ll never find man" in Ice Age soundtrack
and some K pop

1. Shuagang Black 181Z

I got this tube upon reading some raved review that this one sounds better than Nos tubes.

But after comparing this one with Sylvania vt231, I found this one lacking details and transparency compared with Syl vt231 while it sound warm and organic.

i had done shootout with other tubes again this time.

It is just above average in detail, transparency, dynamics.

But it sounds balanced and musical with deep soundstage.

Overall it is a pretty good tube, but I will not buy at 120$ again.


2. RCA gray bottle made in 50’s

This RCA sound similar to RCA vt 231.

But RCA vt231 is more transparent and more detailed than RCA gray bottel.

Gray bottle has very good bass and macro dynamics also with nice decay thus it also sound similar to 1587 Melz.

This make overall sound round and warm almost analog like.

Some people may find this tube boring while other people may like this.


3. 1578 Melz

After listening to RCA gray bottle, I switch to 1578 Melz made in 1980 for comparison.

They sound similar with nice bass, decay and wide soundstage.

But 1578 is slightly better than RCA gray bottle on every respect and more air than RCA gb.

1578 give best dynamics and widest and deepest soundstage while it may sound little bit closed in compared with Syl Vt231.

This one will be good for hard rock, metal music and big orchestral music.


To me this is the "Holy Grail" of 6sn7 tubes.

I had bought three pairs of 1578( two made in 1980 and one made in 1983).



4. Sylvania GTB Tall bottle made in 1955

This one sound very similar to "Bad boy " version made in 1952 with excellent bass and macrodynamics.

It also has some lively treble but overall kind of mediocre.

Not a bad tube but not excellent as Vt 231s.


5. Sylvania WGT brown base made in 50’s.

I got three tubes at 65$ including shipping and tax from Ebay.

It could be hit or miss to buy Nos tubes from Ebay.

This one is clearly big hit.

This tube give lively details, good speed and transparecy.

It sounds almost like Raytheon VT 231 at much lower cost to me.




DetailsTransparenSpeedTonalityTreble ExTreble ClMi DynMac DynS. DepthS. widthNet costTotal costTS bgrp9.5​9.5​10​9​9.5​10​9​8​9.5​9​575​93​RCA vt2319​9​8.5​9.5​9.5​9​8.5​9​8.5​10​89​90.5​KR vt2319​9​9​10​8.5​8​9​10​9​9​83​90.5​RT vt2319​9​9​8.5​9​8.5​9​9​8.5​9​92​88.5​Syl vt10​10​9.5​8​10​10​9.5​7.5​9​9​100​92.5​Bad boy8​7.5​8.5​9​7.5​8.5​8.5​9​8.5​9​215​84​1578​8.5​8​9​9​8​9​9.5​11​10​10.5​250​93.5​S 181z8​8.5​8​9​8.5​9​8.5​8​9​8.5​120​85​RCA gr8​7.5​8​9​7.5​8​8.5​9.5​9​10​105​84.5​Syl Tall8.5​8​8.5​8​8​8​8​9​8​8.5​108​82.5​Syl Wgt9​9​9​9​9​8.5​9​8​8.5​8.5​45​87.5​Treble Ex means extensionTreble Cl means clarity
https://www.head-fi.org/threads/shootout-of-nos-6sn7-tubes.932083/

So far 1578 Melz got the best score just above TS bgrp at less than half cost.

All vt231 tubes made in 40’s are excllent.

Syl Wgt brown base was the best among the tubes made in 50’s at only 45$ per pair.