Stock Marshall Tube Codes

[craiguitar]

Well, I finally found a thread listing the stock marshall tube codes. I have 2 preamp tubes I'd like to identify. VLVE-00041 and VLVE-00035-15 but unfortunately neither of which are listed above. I was hoping to determine the positions in the amp which they are from. I think one of them is for the phase inverter V4. Any clues?

 

[Drewser141]

As long as we're identifying preamp valves, I have a few in my TSL122 that I can not find. Any help appreciated as I might have put them in backwards in my recent repair/upgrade (more on that later). So here is what is printed on them, I can take pix if necessary. (feel free to tell me if I did actually put them in bassackwards)

V1- VLVE 00051 WK0401 (white marshall logo)
V2- VLVE 00041 WK42 (white marshall logo)
V3- VLVE 00008R WK1 (black marshall logo) The R is smudged
V4- VLVE 20040 WK21 (NO logo)

As long as we're at it, what does the WK part mean?

Thanks in advance!!!

 

[big dooley]

wk is probably the week of manufacture within a certain year... as for the other tubes not being mentioned in the list, some high quality pics could help

 

[Drewser141]

As requested.

 

[big dooley]

hm... the second and third tubes look like Ei's to me... no idea about the others

 

[Drewser141]

I seem to be building a collection of 12A?7 tubes, so I'm noticing differences in construction, materials and other details. Early 2000s probable Shu or EI. Good sounding suckers and with the new Trannys and choke installed she sounds like the monster she truly is. Thx for your input!

 

[bloodspoint]

Hey,

Thanks for stickying this, made it easy to identify that the 70 marked EL34's in my 2006 DSL are JJ's, though probably getting long in the tooth, they look original.

My question is the preamp tubes I have are marked 84 and 85, and I don't see those in the list. Any idea what those are?

Thanks,

Sean

 

[RussBert]

What is this??

VLVE-00008R

marked WK3

Plated copper pins, saucer getter

 

[maltone]

Dooley, the VLVE-00010 EL34 Svetlana, is what shipped stock in my 2008 DSL 100?

I was under the impression they were Winged =C=. Not that it matters, the originals sounded really good — until 1 had a dead short last week.

They've been replaced and the amp biased with NEW Winged =C= EL34's.

As a side note, and I'm not sure if my question even belongs here, but here goes...

After re-biasing the new EL34's using:
25 ÷ 466 X 0.65% of plate dissipation + 0.005 screen current.
39-40 mA PER TUBE
BIAS RANGE PER SIDE = 78mV — 80mV MAX.

I instead went with 60%, @ 37mA per tube, 74 per side

Lane Sparber was saying that

Modern tubes are made cheaply and they often fail out of the box and fluctuate a lot from tube to tube. Make no assumptions as to how long ANY new tube will last (or how well it will perform) over time. It's a crap shoot.

QUESTION:
If the older Brimar or Mullard branded tubes of yesteryear were, or are regarded as superior, more robust construction etc, what made them higher quality if we compare them to modern EL34 construction, materials etc.

In other words, what would it require today — with all of the modern manufacturing techniques, to make a tube — exactly like the ones from the 50's and 60'? Not just electrically, but structurally the same?

 

[big dooley]

Dooley, the VLVE-00010 EL34 Svetlana, is what shipped stock in my 2008 DSL 100?

I was under the impression they were Winged =C=. Not that it matters, the originals sounded really good — until 1 had a dead short last week.

svetlana is winged C... in europe...
the original svetlana lost their right to carry their own name in the US market to new sensor and that's why they are called winged C's
marshall uses the original svetlana's, so your DSL came with winged C's

 

[maltone]

Dooley, if I bought NEW Winged "C" (SED) EL34's for $59.46 for a matched pair,
and then compared them to the Svetlana EL34's at $41.95, both available from The Tube Store,

You're saying that both of these tubes are identical Svetlanas, but 1 pair is re-branded by SED?

 

[big dooley]

no, you have two kinds of svetlana's...
the originals being made in st petersburg russia, being called winged C today
and imposters from new sensor being made in saratov, russia

in europe, winged C is still called svetlana next to the fake svetlana's being made in the sovtek factory in saratov

they are pretty easy to tell apart:

original svetlana (winged C):

imposter svetlana (sovtek made)

note the difference in the structure on the sides of the plates, the imposter has 4 clamping holes on each side, while the original is spotwelded

 

[maltone]

Aha. So, if mine have the Winged C logo, then they're the "real" ones.

My god, what a strange industry!

 

[big dooley]

Aha. So, if mine have the Winged C logo, then they're the "real" ones.

My god, what a strange industry!

yes... even more strange is that in the early to mid 90's the originals came with an "S" logo... my bandmate still has a quad of these in his 2210

as for new sensor tubes:

svetlana, electro harmonix and mullard reissue EL34's in a row...
to me they look awfully close to eachother...

 

[maltone]

You know what this niche industry needs... A company like Marshall to actually manufacture their tubes offshore, but using the same materials, vacuum process, thicker glass, mica spacers - whatever made the older RFT EL34's so robust - and durable - and repeat that using modern manufacturing. I don't know why it's so difficult for these companies to adopt a better way of making them.

Now, metals can be strengthened at the molecular level, realigning the molecules to form criss cross patterns for even greater strength. This seems like the perfect process for the internal components of tubes.

What I'd like to know, is how much would a quad of EL34's have cost in 1955-1960 compared to now. If they were better made then, how much more would they cost today to make them to the same standards as the "old" ones?

 

[big dooley]

impossible...
back in those days they used materials that are now banned because they're not friendly to the environment
marshall just has to work with what's available... remember that in the early 90's they were forced to put 6L6's and 5881's in their amps, as their supply of EL34's had dried up (coming from tesla)... fortunatly svetlana (winged C these days) came to the rescue

 

[RussBert]

impossible...
back in those days they used materials that are now banned because they're not friendly to the environment

That is simply not true. It's a matter of economics, there just isn't a high demand for vacuum tubes anymore

 

[maltone]

Re: RussBert

True, it is entirely based on economics. I know it's a very small market. I just hate the fact these companies simply re-brand - as if the players in the know can't tell the difference.

Market demand drives everything, I just think it wouldn't be that difficult to adopt a better way of constructing them. I've never heard "old" tubes, so I wouldn't know the difference anyway, but it seems like the failure rates are extremely high at the manufacturing level for these things.

I wonder if the CEO of New Sensor has ever thought to ask why? Or, can't we make these things better - like they used to be made. If they can make modern day OT's - to sound like the older vintage ones, because manufacturing techniques, and quality of alloys and metals has improved - you'd think that would be applied to the other areas of manufacturing within this industry.

 

[JohnDanese]

Here is a preamp tube not on the list: Marshall VLVE-00008R. Very faintly it is marked Made in Russia.

 

[JohnDanese]

Also ( cannot upload photo for some reason). V1 preamp tube marked:
VLVE20040 ( no dash after VLVE and does not have Marshall Logo).