Shootout of Nos 6sn7 tubes


I will have shootout between TS BGRP, RCA vt231, KR vt231, Syl vt231, Raytheon vt 231 and "Bad boy" next weekend.

If I get MELZ 6N8S 6SN7 Metal Base next week, then I will also include it in shootout


RCA5691, Psavne Acme 300B, Psavne Acme 805 are also being used in Line Magnetic 508 amplifier.

Speaker will be Lansche 4.1 with plasma tweeter.

Digital source will be Dave and HMS fed by ripped CD stored in ssd drive of Cocktail audio x30.


I will play

Eva Cassidy's 'Autumn Leaves"

"Trinity Sessionn " by Cowboy Junkies

For classical orchestra, "Trittico" directed by Fennel.

"Still harry after all these years" will be for fusion jazz.

Any more suggestion gentlemen and ladies.

Thomas
128x128shkong78
If you have issues with the 1578's, your first course of action should be to contact the seller.  I'd avoid trying things like re-soldering unless you can't get satisfaction from the seller, or you don't care about taking a loss if you're unable to return them due to modifying them.
When you refer to "closed in highs" do you mean less extension or less high-end energy than 1970s?

The 70's 1578 have more high end extension which translates into a more balance sound. 

One person claimed that best 1578 that he had heard was made in 63.

There are many variations among the Nos tubes.

I have three pairs of Raytheon vt231 but they sound different from each other.

I also enjoy Russian 6n8s made in 53 with nice bass, air and sparkle.

Now I have around 100 tubes of 6sn7 variants.

I am listening to National Union black glass which will be the last one in the shootout.

I will summarize my findings this coming weekend.
I am listening to "Vision of Love " by Maria Carey through 1578 that I had bought from Russian dealer ( made in 80 same source as bought by big-greg and Lordcloud).

i do not notice any high frequency noise out of it.

Another interesting thing is that I had felt 1578 rather closed in with RCA 5691 (6sl7) in front of 1578 in Line Magnetic 508 amp.

But using Russian 6n9s made in 53 instead of 5691, this 1578 does not sound closed in but almost perfect neutral balance.


Now I am playing Miles and Coltrane "Straight No Chaser" track.

Trumpet sounds so clean with enough sparkle but not too hot.



I didn't feel like the 1578s had closed in highs and I didn't notice any noise in the upper registers, just the crackling out of one tube.  They definitely had more pronounced bass, perhaps that gives some the impression of "closed in highs"?