[hdtv00]

Can I trouble you for some pics. I totally believe you I just want to gather more facts, I got nothing else to do but get to the bottom of this. I just won an auction for a legit 421A for $190 so soon enough I'll have one on hand and not just mass amount of pics. Please post pics in here, it will really help others not waste $200+ on 421A's if it's the same as 5998's.

 

[jhljhl]

This is a 5998.
 

 

[jhljhl]

I saw this on ebay.  It is a Tung Sol 421a.
 

 

[hdtv00]

II.a.ii) [RARE] $80 (NOS) Tung Sol 421A [Dual D getter]:
 
Basically it's a Tung Sol 5998 labelled "421A" and has the black 5998 plates. Do not have one myself but pretty sure it's either the same tube as the 5998 with different getters or a 5998 with 421A specifications without the WE 421A construction differences.
 
As I was directed to here for tubes of this nature.
http://the-key.enix.org/~krystal/review-tube-bottlehead.html

 

[Franatic]

First of all let me state that I respect the opinion of everyone who has submitted to this thread. I've owned all the better power tubes for my Woo WA2 amp. I own or have owned The Tung sol 7236, the RCA 6AS7g, the Gec 6080 and Gec 6AS7G, I've owned both 5998s and 421As. The 421A is a much superior tube, IMHO. It has this amazing ability to give "air" to the system. It gives the soundstage lift and separates the instruments in layers with superior imaging and details. When I first heard it I was taken aback as it is not a quality possessed by any other power tube. 
 
I have two different manufactured pairs. The Western Electric 421A which has bottom getters and National Electronic 421As which have top getters. The Nationals have more Air , the Westerns better bass. Both brands are sensational and sounded much better than the 2 Tung Sol 5998 pairs I had (now sold).
 
Let the debate continue, my ears convinced me. Nothing else but SQ matters to me. The 421A is king......followed by the GEC 6AS7G.

 

[leftside]

Sorry to resurrect an old thread, but I recently obtained a second pair of WE 421A. The construction is a little different to the other pair of WE 421A. I also have a pair of Tung-Sol 5998 and the construction of these is exactly the same as the latter WE 421A I mentioned. Perhaps this could explain the differences people have heard? I'm going to give all 3 pairs a good listening session this weekend, but for the time being here are pictures of the different WE 421A's. The biggest difference being the chrome top, the lettering and most importantly the construction at the bottom of the tube. They are quite different and most noticeable are the two circular pieces of wire.

 

 

 

 

 

 

 

 

 

[Franatic]

The pieces of wire you are referring to are called the getters. I have 2 pairs of 421as. One pair from the early '60s has "D" getters on the bottom. The latter pair from '78 has a "O" getters on the bottom. Both pairs have charcoal plates but the older pair also is a bit taller with slightly larger plates. So as far as I can tell that is the pattern, earlier 421As "D" getters, latter ones "O" getters.
 
I formerly had 2 pairs of TS 5998s and both had the shiny black plates that definitely look different than the plates on the 421as. I sold those off.
 
Do a sound test. I found the 421As superior........by a good margin. Larger soundstage, layers of air, increased dynamics and imaging, but yet an amazing delicacy that made its sound signature irresistable and the top power tube I tested, surpassing even the very excellent GEC 6AS7G.
 
**Edit note: Despite the difference in construction, I found both the early '60s tubes and the '78 pair had practically identical sound signatures.

 

[leftside]

I'd say the plate sizes on mine are the same. If I shine a flash light into the chrome top one I can indeed just about make out the D shaped getter you mention. There are other subtle differences in the construction as well.

I will certainly listen to all 3 pairs this weekend.

 

[Krutsch]

  The pieces of wire you are referring to are called the getters. I have 2 pairs of 421as. One pair from the early '60s has "D" getters on the bottom. The latter pair from '78 has a "O" getters on the bottom. Both pairs have charcoal plates but the older pair also is a bit taller with slightly larger plates. So as far as I can tell that is the pattern, earlier 421As "D" getters, latter ones "O" getters.
 
I formerly had 2 pairs of TS 5998s and both had the shiny black plates that definitely look different than the plates on the 421as. I sold those off.
 
Do a sound test. I found the 421As superior........by a good margin. Larger soundstage, layers of air, increased dynamics and imaging, but yet an amazing delicacy that made its sound signature irresistable and the top power tube I tested, surpassing even the very excellent GEC 6AS7G.
 
**Edit note: Despite the difference in construction, I found both the early '60s tubes and the '78 pair had practically identical sound signatures.

 
I've never seen the later models. I have five 421a tubes from an estate sale from a former Wisconsin Bell telephone employee (the tube dealer in WI had a case of them, along with a bunch of 422, which I am sorry I didn't buy). They all have the bottom 'D' getters and charcoal plates. I also have a collection of TS 5998 tubes, none of which look like my Westys.
 
And I will attest to your findings on sound. No comparison. The 5998 tubes (at least mine, anyway) have a nice bump in power, but have a lot of upper bass bloom - so much so, they never get used.
 
I also have a pair of GEC 6AS7g "Brown Base" tubes; and, yes, they do sound excellent. I rotated between the two in my WA3 for about 3 months, really acclimating to their lush sound, but I popped a 421a back in this week and was pleasantly surprised at the clarity and tone, as well as the imaging characteristics you describe above. Really, they are in class by themselves.
 
That said, it's not a stretch to imagine that at some point, WE had to purchase/re-brand a bunch of TS-5998 tubes to fill a large order. Other tube companies did this when they didn't have the stock on hand, when needed. I have a pair of Telefunken E288CC tubes and I've been told that they are really Siemens tubes and TK never made a 288.

 

[leftside]

Mine have "O" getters on the bottom and the others have the "D" getters on the chrome top (as do the Tung-Sol's).

 

[Franatic]

  Mine have "O" getters on the bottom and the others have the "D" getters on the chrome top (as to the Tung-Sol's).

Oh, you have the "D" getters on top, as I can see now on my big monitor. Interesting, let us know how they sound.
 
I have a pair of National Electric 421As, that have the getters on top. They are great sounding tubes also, but a slight notch below the Westerns in refinement. I tried to verify who actually made them. I was told they were made for Western by National, but someone else said the opposite. Either way they are a great pair for the $160 I spent on them.....and better than their 5998A cousins.

 

[leftside]

No real surprise, but I found the TS 5998 and the WE 421A's with upper D getter to sound very similar. Perhaps a little more detail with the 421A's. Their construction is exactly the same so I wasn't expecting too many differences. I did notice quite a few differences with the lower O getter WE 421A's. Details that I had to concentrate to hear properly with the other tubes came easily with the lower O getters. These tubes are from 1953.

 

[leftside]

Correction: After speaking with a couple of dealers I know, it appears the "lower O getters" are from 1985 and the "upper D getters" are from 1958.
 
It is believed that the earlier tube from 1958 is a rebranded Tung Sol (which would explain the identical construction), but the later tube from 1985 is Western Electric.

 

[Skylab]

1985? Huh. Well for sure if there were 421a tubes being made in 1985, it wasn't Tung Sol making them, as Tung Sol was long gone by then. Cetron, who bought Tung Sol, continued to make some of Tung Sol's tubes like the 6336, sold under the Cetron name, for some time, maybe even as late as the 1980's. But not the 5998, I don't believe. So perhaps WE had to start making the 421a, and thus the slight design change.

 

[leftside]

Yes, I was also very surprised at the late date. Confirmed for me though that these are genuine WE, and not Tung Sol, and could very well explain the differences people have reported. Construction is totally different to the earlier tubes, and there is a noticeable difference in sound quality (rare in this particular case that the later tubes sound better). This information came from Brent Jesse. He is one of the most helpful sellers I've dealt with.