[Seamaster]

"The 6AS7G is the exact equivalent of only the 6080. Other than appearance, these tubes are the same."

but they sound different

 

[Skylab]

Quote:

Originally Posted by IceClass /img/forum/go_quote.gif Thanks for the explanations there SkyLab. I'd been cruising Ebay to look at tubes and my mind was a mess of numbers. So, I'm assuming that the WA2 has always used the same Power tubes and only the rectifier tubes have been changed. Therefore, my WooToo should handle any of the 5998/7236/23996AS7G power tubes. As for the 5998 tubes, what are the variants? I see them advertised as black gate, triple mica etc What do these terms refer to and are some better than others?

All 5998's are made by Tung-Sol, and they are all pretty much the same. Some have a top-getter, and some a bottom getter, but I have never detected any difference in the sound of 5998's.

There is also the GE-made 5998-A, but these are not a real 5998, and don't sound any better than GE's straight-bottle 6AS7GA.



Quote:

Originally Posted by Seamaster /img/forum/go_quote.gif "The 6AS7G is the exact equivalent of only the 6080. Other than appearance, these tubes are the same." but they sound different

Oh yes, most definitely - they are just the same in terms of operation points/electrical properties. But I much prefer the 6AS7G over the 6080, universally.

 

[Seamaster]

GEC, Macorni make two different style 6AS7G. One with straight brown or black base, one with cup brown or black base. At $150+ a pair, look no further on 6AS7G type, it is end of road.

One question pop up in my head:
Can we use different other tube with adapter to replace 6AS7/6080 type? Anyone?

 

[Skylab]

The GEC ("cup" brown base) are my favorite 6AS7G as well.

 

[IceClass]

What's the difference between 6AS7 and 6AS7G tubes?

 

[Seamaster]

6AS7 is mother type. 6AS7G is sub division of the family. Most europian use 6AS7G code, or A1834

Skylab explained:

The 6080 is identical in performance to the 6AS7G. The 6AS7G is a ST/"Coke Bottle" glass type, whereas the 6080 is straight bottle. I almost universally prefer the 6AS7G. I have about 100 6AS7G/6080/6520/5998 tubes.
And it is the 6520, not the 6528, that is equivalent to the 6AS7G. The 6520 was only made by Tung-sol.

Of the US Makers, RCA-branded 6AS7G’s are by far the most common, and they sound good. Tung-Sol also made 6AS7’s, and they are a little better sounding IMO than the RCA’s (they are also constructed a little differently), but they are much harder to find, and not worth paying an enormous premium for. GE, Sylvania, Chatham and Raytheon also made 6AS7G’s, but they also don’t seem to offer anything the RCA’s don’t sonically, IMO. There are other brands available, but I am pretty sure they are just branded versions of the other manufacturers listed. The JAN (Joint Army Navy) versions were supposedly somehow selected specially (tighter tolerances, etc), but there are no construction differences with the non-military versions. I have seen JAN-6AS7G’s from RCA, GE, Tung-sol, and Chatham (which at one point was bought by Tung-Sol).

The GEC UK-made 6AS7G (A1834) are my favorite of the 6AS7G - they have brown bases and a different plate structure than the US types.

Finally, there are the Russian equivalent 6N13S, but I really don’t care for these. I have seen Amperex 6AS7G’s that say "made in Holland", and Ultron "made in W. Germany", but both of these were almost certainly Russian.

The primary construction differences in a 6AS7G are that some are made with a top halo getter (and the resulting chrome top flashing appearance) and some with bottom-mounted D getters (where the flashing is at the base and the tube has a “clear top” appearance). RCA also made “Grey Plate” and “Black Plate” versions – all other makers 6AS7G’s have black plates. Supposedly the Black plates sound better, but I believe this is either untrue or extremely subtle at best. Some also have an additional metal “skirting” shielding the wiring as it travels from the base to the grid, but I have not been able to attribute any real sonic differences there either. Bottom line – any Western 6AS7G is a good choice, as long as it’s in good shape and isn’t horribly microphonic.

There is also the 5998 tube, made only by Tung-Sol regardless of branding, which does have different operating characteristics, and may or may not work in any given 6AS7G application, although it does in the amps I have, snd sounds a little better than most 6AS7G's. In general the 5998 offers slightly more neutral sound, slightly better transparency, and are less likely to be noisy. They are approximately 2-3x the price, generally, and I have seen some idiots paying $50 per tube on Ebay when you can buy them NOS from reputable online tube-sellers for $25 each. Still, this is more than double the 6AS7G price.

The 2399 is also a Tung-Sol only tube, and I have never scored one myself, but supposedly it is also just a high-quality 6AS7G.

In general, the 6AS7G is a great sounding tube, IMO. I probably know more about this tube than any other tube type, as I have 4 different headphone amps that use it, and there isn't a lot written about it like there is with tubes like the 12AX7 or 6SN7...

 

[Skylab]

The "G" indicates the bottle type - the ST/coke-bottle/"shoulder" type bottle - as opposed to the GA and GB, which are straight-bottle. All 6080's are also straight-bottle.

 

[Seamaster]

Skylab: What do you thing Telefukan 6080WA (made in Germany)? Any good?

 

[Skylab]

Quote:

Originally Posted by Seamaster /img/forum/go_quote.gif Skylab: What do you thing Telefukan 6080WA (made in Germany)? Any good?

In spite of being labeled "Made In Germany", I am virtually certain they are not - I think they are rebranded, probably from Philips, but maybe GE.

The "Telefunken" 6AS7G's I have seen are *definitely* Russian rebranded tubes. I don't think Telefunken ever made this type of tube.

 

[IceClass]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif You can do much better than the Jan Phillips 6922. But you can spend a lot in the process.

I tried rolling the with the 6922s I had on hand for ****s & giggles.
Surprisingly, both the Electro-Harmonix 6922EH and the Sylvanias gave me a faint hum. Neither had given me any issues in previous use in my Dodd ELP preamp.

And no kidding about how much one can spend on a matched pair of wee little 6922s these days. Do folks really pay over $200?

 

[Skylab]

I personally will not spend that much on a 6922, but some people clearly will!

 

[herroyuihk]

Hello every woo user
I have rolled tons of tubes combination...
Sadly speaking! I have not bought Gold lion U709 yet....
But the best sounding Rectifier is 60~70s round getter Mullard EZ81....
(Square getter mullard EZ81 or 80 is very slow and lacking dynamic??)
The followings are my favorite e88cc + 6AS7 combination...
1.Siemens CCa A1-4........................+ GEC 6AS7...............

(GEC is used...I will try my best to find very good nos GEC 6AS7 )
2.Valvo(philips Holland) E88CC D-getter + Tungsol 7236..........

3.Telefunken CCa .............................+ Tungsol 7236..........

GEC is too thick and warm for Holland tubes
And when GEC is paired with TFK, amp will lack impact....
Sylvania 7236 is quiet good....(I still try its best combination)
So I don't think any brand or Type 6as7 is really superior to others.

 

[BIG POPPA]

Have you tried Mullard CV2984's (6080's)? Very musical tube.

 

[Seamaster]

Quote:

Originally Posted by BIG POPPA /img/forum/go_quote.gif Have you tried Mullard CV2984's (6080's)? Very musical tube.

If he thinks GEC is too thick and warm for him, then CV2984 even more so.

 

[BIG POPPA]

All my cables are silver plated and or have Rhodium connectors, My MS-1's have a Silver plated copper cable. Don't get the Warm sound too much, just get the Silky smooth. Silver is a little pain to break in but once you do it is great, to me it helps with some of the faults of tubes. Makes my listening more enjoyable.