[snip3r77]

Quote:

I remember when I got mine they hummed too.  I guess they must have been pretty new, even though the 337 they came with was well used.  The hum completely went away after only ~1 week, probably ~20 hours of total listening time.

Ok thanks for the assurance. I try to listen to it daily and prays that it goes away.
Cheers.

 

[kramer5150]

Quote:

So I guess the pair of GEC A1834's I bought for $40 I will need to keep for a while

Sure is interesting to watch NOS tube prices soar. Supply and demand, don't ya know. Until they became popular in headphone amps a few years back, the 6AS7G and all it's cousins were not popular tubes. 5 years ago RCA 6AS7Gs didn't fetch $5 each. You could buy a NOS sleeve of 5 for $20 very easily.

Same thing happened to the 12FM6 ~10 years ago with pete millets amp, and a few years before that the ECC86 in the Earmax.  These are low voltage tubes, and had no demand at all for 2-3 decades once small, low voltage consumer electronics went solid state.  They guy at my local used/vintage surplus retailer said they couldn't give them away, and they would just take up shelf space.

 

[hifimanrookie]

Just wondering what is the relationship between the 5998 vs 5998a vs 7236. Was thinking if it's possible to pay non premium price for the 5998 equivalence.

Thanks

Maybe this helps to answer ur question?

http://www.bottlehead.com/smf/index.php?action=printpage;topic=3453.0

 

[snip3r77]

Quote:

Maybe this helps to answer ur question?

http://www.bottlehead.com/smf/index.php?action=printpage;topic=3453.0

Thanks for the link as this can be a guide for us.
 
Since we're using the 339 , the effect might not be the same as the crack?

 

[rosgr63]

Quote:

Maybe this helps to answer ur question?

http://www.bottlehead.com/smf/index.php?action=printpage;topic=3453.0

 
Thanks for the link, great review.
 
What is missing is the Black Base Osram 6AS7G.

 

[Ultrainferno]

Quote:

About the 5998 tubes:
 
[size=7pt]-These tubes are easily recognizable from their glossy black dimpled "Domino" Plates. If the plates are carbon grey instead of black, it's a WE421A (See Western Electric 421A). [/size]

 
I'm running upstairs now to check my stock! I never heard of this. Can anyone confirm?

 

[hifimanrookie]

My god..i checked my5998's..ifthis is true then my 5998's are actually we 421a's as the plates are carbon grey and not black....can someone in the know confirm this? Could it be i have been lucky when i bought my pair last january?

 

[Beefy]

Quote:

I'm running upstairs now to check my stock! I never heard of this. Can anyone confirm?

 
I don't have access to the tube stock that the person in the link does, but I am pretty good at collating data, and there is no evidence whatsoever that the 5998 and the 421A are different tubes. All evidence indicates that the 421A is simply a rough cherry pick of 5998 for slightly higher transconductance.
 
Thus, while the 5998 are the best tube I have heard in my Crack...... I only paid $80 (inc. shipping) for two, and there is no way in hell I would recommend paying way more than $100 for the same tube just because it is labelled as a 421A.
 
Quote:

if this is true

 
If you want it to be true, then it probably is. But engage your common sense brain, and I would be far less convinced.
 
[EDIT] Actually, if you all go to the original thread and read it in its entirety, the author concedes that the 5998 and 421A are the same thing, and that the plate colour is related to tube age. All these people hearing magical improvements with the 421A are almost certainly just hearing fractionally volumes due to the higher transconductance, or the blissful confirmation bias of spending lots of money on something that sounds moar bettar.

 

[hifimanrookie]

I don't have access to the tube stock that the person in the link does, but I am pretty good at collating data, and there is no evidence whatsoever that the 5998 and the 421A are different tubes. All evidence indicates that the 421A is simply a rough cherry pick of 5998 for slightly higher transconductance.


Thus, while the 5998 are the best tube I have heard in my Crack...... I only paid $80 (inc. shipping) for two, and there is no way in hell I would recommend paying way more than $100 for the same tube just because it is labelled as a 421A.



If you want it to be true, then it probably is. But engage you common sense brain, and I would be far less convinced.

I am just curious minded...but for my 5998's NOS matched pair i paid 190usd ex postage!

But they sound soooo good on my 337! I have the bendix 6080wb graphite plates also..and what the reviewer said about those is true, soundwise compared to the 5998...so he knows his tubes a bit..

And yes i know there always have been a debate wheter the we421a was a better tube then the 'normal 5998' or just what u just stated..i cant confirm it myself..as i dont have both the black plated and grey plated 5998's..maybe ultrainferno does? So he can check if there actually is a difference in sound? Until then i just enjoy my tungsols tuned 337..

 

[Beefy]

Quote:

I am just curious minded...but for my 5998's NOS matched pair i paid 190usd ex postage!

 
Yeah, for $190 you could buy a pair of RCA 6AS7's, and still have $160 left for good quality spirits. I can confirm that this combination sounds far better than the 5998.

 

[hifimanrookie]

Yeah, for $190 you could buy a pair of RCA 6AS7's, and still have $160 left for good quality spirits. I can confirm that this combination sounds far better than the 5998.

In my 337 the combo of ts 5998 powertubes and ts sj7gt meshplates is best match for my ears..rca was a bit to warm for me..but its all about the amp u have and the phones and ur personal taste ofcourse..

 

[Skylab]

No one will ever convince me that the WE421a is anything other than a rebadged Tung-Sol 5998. At MOST, I will allow that it might be a "carefully selected" 5998.

 

[rosgr63]

I thought they TS 5998 and WE421A were different tubes.
However the Data Sheet says otherwise.
 
 
 
 
 
 
 

 

[Beefy]

Quote:

In my 337 the combo of ts 5998 powertubes and ts sj7gt meshplates is best match for my ears..rca was a bit to warm for me..but its all about the amp u have and the phones and ur personal taste ofcourse..

 
Have you tried the RCA with a high blood alcohol content? Guaranteed better.

 

[hifimanrookie]

Have you tried the RCA with a high blood alcohol content? Guaranteed better.