[shellylh]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif I don't like the re-issued tubes at all, ESPECIALLY the 6SN7 types. The 6SN7WGTA will work very well in the extreme. You can get them for less than $70 if you hunt around. I have seen them for crazy prices like $250/pair, but I have bought them for $40/pair before.

Thanks, I will keep my eye out for a good price on the 6SN7WGTAs and not bother with the re-issued tubes.

 

[Webrider]

You can find a zipped copy of the SP Extreme Tube Guide v2.01 at this link

http://www.head-fi.org/forums/attach...1&d=1226361094

Enjoy

 

[sacd lover]

Quote:

Originally Posted by Webrider /img/forum/go_quote.gif You can find a zipped copy of the SP Extreme Tube Guide v2.01 at this link http://www.head-fi.org/forums/attach...1&d=1226361094 Enjoy

There are a lot of errors on the spread sheet ....

The 2C51/5670 IS a recommended tube with its own specific 2c51 adapter. Tubes for this adapter include 396A/ 2C51/ 5670 and Russian 6N3P. The 2C51 works well with low mu power tubes like the 6AS7G/ 6080.

The 6350 is another tube with its own adapter. The other tube you can use is the 6463. This tube IS NOT compatible with the ECC Type#1 adapter.

The ECC Type#1 adapter has the 12xx7 series pin out. You can use the 12AU7/ 12AV7/ 12AZ7/ 12AT7/ ECC99 etc... Some of the 12xx7 series have the correct pinout but will very likely have to much gain, such as the 12ax7/5751. The 12AV7 has numerous subs such as the 5965/ 6414/ 6829 and 7062. The 7062 I recommend is the Amperex 7062. But the Philips SQ 7062 is a good tube too.

The ECC Type#2 adapter is for the 6CG7/6GU7/6922/6DJ8 and lesser known tubes like the 6BK7A or 6BZ7 .... to name a few. The 6GU7 is probably my favorite gain tube and they only cost $5.

The 5687 adapter is mainly for the 5687. But, this adapter also allows the use of the 6900/ 7044 and 7119. The 6900 is hideously expensive and is actually designed to work best in a circuit that runs the 5687 types to hard.

The 7N7 adapter is again specific for the 7N7 and is equivalent to various 6SN7GT/ VT231s depending on the vintage. This tube was made for a long tine and spanned the changes in 6SN7GTs to 6SN7GTAs to 6SN7GTBs. You can also use a sweet sounding short bottle roundplate tube called the 7AF7. If your amp can handle a tube with a gain/ mu of 70 you can theoretically use the 7F7; which is equivalent to the 6SL7GT.

EDIT: Ok I am adding some more corrections ....

There is no such tube as the 6456 I am aware of.

The ECC182 should be E182CC .... and this is the European designation for the 7119.

The 5844 listed as working with the ECC Type#1 adapter WILL NOT.

The PCC189 is a 7.6 volt ECC189/6ES8 and IS NOT compatible.

The PC88/ 7DJ8 is a 7 volt 6DJ8 and will not work in most applications.

The 8SN7GTB listed as working with the 12 volt option WILL NOT work at 6.3 or 12.6 volts .... nor will the 8CG7.

 

[Happy Camper]

Sweet. I pm'ed the OP today for a new copy but this is it. Thanks Webrider.

As usual, sacd lover comes to the rescue. Thanks Earl.

 

[Skylab]

Also, the 6SU7GTY is listed, but the 6SL7 is not, and it should be.

 

[shellylh]

Thanks to webrider for the spreadsheet and sacd_lover and skylab for the corrections!

 

[shellylh]

I just got a pair of NOS GEC 6080WA tubes in the mail today. I am using them with a Tung Sol USN-CTL-6SN7WGTA driver tube in the Extreme. These seem to be really detailed!!! They don't seem to be quite as lush as the Tung Sol (Chatham) 5998s. Of course, they are not burnt in yet. Too bad I have to go out of town tomorrow!

 

[Skylab]

That jives with my general impression of the 6080's I have tried (including the Mullards) - they are a tube that is more on the detailed/lean side versus the 6AS7G.

My impression has been, generally:

Lush/Warm < --------------------- > Lean/Bright

6AS7G ----- 5998 ------- 7236 ------- 6080

Of course, there are differences within type based on construction.

So many tubes, so little time!

 

[sacd lover]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif That jives with my general impression of the 6080's I have tried (including the Mullards) - they are a tube that is more on the detailed/lean side versus the 6AS7G. My impression has been, generally: Lush/Warm < --------------------- > Lean/Bright 6AS7G ----- 5998 ------- 7236 ------- 6080 Of course, there are differences within type based on construction. So many tubes, so little time!

I would tend to disagree here. The brand makes the most difference in my experience. Moreover, these tubes were rebranded to the nth degree. Alot of people think they have TS etc... 6AS7s when they, in fact, have RCAs. Try a RCA 6080 and tell me if you think that tube is bright. Raytheon 6080WBs are also on the dark side. GE 6080s, for instance, can sound almost harsh and Sylvania 6080s are on the leaner side. TS 6080WAs seem about right. Bendix 6080s are really good but I dont think they warrant the huge increase in price over the standard 6080s I like.

Everyone made 6080s, RCA made most of the 6AS7Gs and TS made most of the 5998s. I dont have enough 7236s to be sure who was the major player with the 7236.

 

[Golden Monkey]

7236 - Tung-Sol and Cetron, mostly.

 

[Skylab]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif I would tend to disagree here. The brand makes the most difference in my experience. Moreover, these tubes were rebranded to the nth degree. Alot of people think they have TS etc... 6AS7s when they, in fact, have RCAs. Try a RCA 6080 and tell me if you think that tube is bright. Raytheon 6080WBs are also on the dark side. GE 6080s, for instance, can sound almost harsh and Sylvania 6080s are on the leaner side. TS 6080WAs seem about right. Bendix 6080s are really good but I dont think they warrant the huge increase in price over the standard 6080s I like. Everyone made 6080s, RCA made most of the 6AS7Gs and TS made most of the 5998s. I dont have enough 7236s to be sure who was the major player with the 7236.

I don't disagree that brand and construction makes a HUGE difference - you're right of course, it does. And I have not tried nearly every tube. But I did find the RCA 6080 to be brighter than the RCA 6AS7G, and so my general theory (at least for me) still holds.

Tung-Sol and Sylvania made 7236's - I have some of both. Tung-Sol also made 6AS7G's which are quite different from RCA's. I'm not positive that anyone else made 6AS7G's or just got them from RCA.

 

[shellylh]

Does anyone have any information on the GEC 6080WA's? Are they a rebranded _______? I have a pair of TS 6080's and the GEC sound brighter to me at first listen (although I could only listen to the GECs for ~15 minutes and they are not burnt in yet). Unfortunately, I can't use the TS 6080's because one of the channels is about 4 dbs lower than the other when using them (not very pleasant). Does this mean that one of the TS tubes is bad or does it mean that they are just "unmatched" (whatever that means). Sorry for all the newbie tubey questions. [I guess this is not really the right thread to be asking these questions ... oh well.]

Quote:

Originally Posted by sacd lover /img/forum/go_quote.gif I would tend to disagree here. The brand makes the most difference in my experience. Moreover, these tubes were rebranded to the nth degree. Alot of people think they have TS etc... 6AS7s when they, in fact, have RCAs. Try a RCA 6080 and tell me if you think that tube is bright. Raytheon 6080WBs are also on the dark side. GE 6080s, for instance, can sound almost harsh and Sylvania 6080s are on the leaner side. TS 6080WAs seem about right. Bendix 6080s are really good but I dont think they warrant the huge increase in price over the standard 6080s I like. Everyone made 6080s, RCA made most of the 6AS7Gs and TS made most of the 5998s. I dont have enough 7236s to be sure who was the major player with the 7236.

 

[sacd lover]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif I don't disagree that brand and construction makes a HUGE difference - you're right of course, it does. And I have not tried nearly every tube. But I did find the RCA 6080 to be brighter than the RCA 6AS7G, and so my general theory (at least for me) still holds. Tung-Sol and Sylvania made 7236's - I have some of both. Tung-Sol also made 6AS7G's which are quite different from RCA's. I'm not positive that anyone else made 6AS7G's or just got them from RCA.

Assuming you had a true RCA 6080 and not a rebrand yes. But, I have around 50 5998As, 45-50 6080s, 30-36 6AS7s and 10 or so 5998s. With this many tubes you can begin to figure out who made what. Any RCA 6080 I have used is dark and dull sounding, much more so than the RCA 6AS7G.

The TS 6AS7G should have a plate structure like the TS 5998. If not, you probably have different production era RCA.


Moving on .....

Currently some of us have been experimenting with a 6SN7GT to 6F8G adapter. This tube is essentially a 6SN7GT with a plate cap.

Here is a pic of the tube in a Supra ....

Where I am going with this is while I was researching the 6F8G I discovered the 6C8G. The 6C8G is essentially a 6SL7GT with a plate cap. However, this tube while almost identical in most electrical parameters to the 6SL7GT has a noticeably lower gain/ mu of 36 .... compared to the 6SL7GTs documented gain/ mu of 70. So, here is another option to try.


The 6F8G sounds as good or better than any on my 6/12SN7GTs and I suspect the 6C8G will give the better 6SL7GTs heavy competition too. As a plus, the 6C8Gs I found available were the better nos Ken rad/ RCA/ TS and NU types .... and these tubes cost a whopping $3-4 each. I tried them in my Supra-Extreme and even though the electrical environment was less than optimal the tube still sounded very good. If 6SL7GTs work well in your amp this one will too. In fact, the lower gain/ mu of 36 is probably just about perfect with low gain output tubes like the 6AS7G/ 6080.

I bought my adapters on ebay ....

Adapters 6F8G TO 6SN7 6384 TO 6L6 tubes SUB - eBay (item 250332454155 end time Dec-25-08 18:45:54 PST)


6C8G ....

 

[Skylab]

NICE ONE Earl! Can the same adapters for 6F8G>6SN7 be used to adapt the 6C8G to the 6SL7?

 

[sacd lover]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif NICE ONE Earl! Can the same adapters for 6F8G>6SN7 be used to adapt the 6C8G to the 6SL7?

Sure .... I used the same adapter. The 6sn7gt/ 6sl7gt have the same pinout so the adapter makes the same conversion. I always had to much gain from my source to use the 6SL7. But, with this tubes lower gain of 36 I can use this one without any problem.

By the way, since this tube has a much lower plate dissipation (just like the 6SL7GT) I ran the tube in the amp six hours straight to make sure it worked and there were no signs of misbehavoir.