Little Dot Tube Amps: Vacuum Tube Rolling Guide
Apr 2, 2014 at 3:23 PM Post #5,701 of 13,438
Will i be Blue because i still don't have my Tubes and those adapter parts from snail mail inc.in Chinada.
Thanks for those Links Mordy.I'am expecting 2 russian 6AS7,6H8C and  8 RCA 6SN7 (got theme from Eb auction)I hope i don't get that Blue feeling this weekend.
 
Apr 2, 2014 at 3:26 PM Post #5,702 of 13,438
  Here MIKELAP is a nice tube for the little hybrid amp. Thanks!

beerchug.gif

What type of Opamp do you have in that amp? Pardon me for asking.
 
Apr 2, 2014 at 5:22 PM Post #5,703 of 13,438
Apr 3, 2014 at 10:49 AM Post #5,705 of 13,438
Yesterday I received a Sylvania Gold Brand 5670 (2C51/396A) with gold pins. These tubes are typically $40 to $50 each, but I found this one (1950's with D-getter) for only $10.00. It's obviously used and a little ratty looking, but it allowed me the opportunity to try one for cheap. I spent a couple hours with it last night, so I can't say that I know it's sound well, but I can say that I like this better than the Bendix I got a few days ago. So unless something changes, this is now my favorite 2C51.
 
While there is no basis in fact, sometimes I find myself thinking that big tubes have big bass and little tubes have little bass. Well, this little tube quickly dispels one of that notion! lol Great bass, great highs and Sylvania's signature smooth mid range make this little guy a winner. :)
 

 
Short and squat. :)
 

 
Apr 3, 2014 at 12:57 PM Post #5,707 of 13,438
  Which pinout does the 5670 tube use? 12AX7 or 6DJ8?

 
Neither. It is different from both of these. I am using an adapter, 2C51 on top and 6DJ8 on the bottom. Or you could simply re-configure one of your 9-pin sockets:
 
Pin
1          heater
2          cathode #1
3          grid #1
4          plate #1
5          shield (connected to pin 8)
6          plate #2
7          grid #2
8          cathode #2
9          heater
 
Apr 3, 2014 at 2:41 PM Post #5,708 of 13,438
After rolling 6SN7 and ECC40 from the 1940's and 1950's, I am beginning to think that that period of time was truly the golden age of vacuum tubes in the West. Considering how much I like my 1961 Heerlen-made E80CC, I decided to try to find one from the 1950's. This tube was first introduced around 1952, so hoped to find one from the mid 1950's. Well, I managed to find and purchase one, and it arrived today. At the time I purchased it, I wasn't sure of the manufacture date. The vendor couldn't make out the entire production code, but did provide the first line, "WK3".  With a change code of "3", I figured it was pretty early, as my 1961 has a change code of "8". I am pleased to discover that this one was manufactured in February, 1955. And further, I was surprised to discover this tube was manufactured in Eindhoven. The full code is WK3 45B.
 
I have the tube in my amp as I write this, and it sounds great. But then, recently, it seems almost every tube sounds great on first listen... time will tell.... :)
 
1961 on the left, 1955 on the right, with pinched waist (neck?) and D-getter
 

 
Apr 3, 2014 at 2:45 PM Post #5,709 of 13,438
Hi G,
 
If you don't mind, a table showing which tube pin on my breadboard goes to which number on the Vector adapters right and left would be much easier for me to understand. Remember this table?
 
 
9 Pin socket                                 Left LD socket                    Right LD socket
 
1 plate triode 1                                     5
2 grid triode   1                                     1
3 cathode triode 1                                 2
4 heater                                                                                           3
5 heater                                                                                           4
6 plate triode 2                                                                                 5
7 grid triode 2                                                                                   1
8 cathode triode 2                                                                             2
9 Shield tied to pin 8 at the socket
 
Apr 3, 2014 at 2:59 PM Post #5,710 of 13,438
  If you don't mind, a table showing which tube pin on my breadboard goes to which number on the Vector adapters right and left would be much easier for me to understand. Remember this table?
 
 
9 Pin socket                                 Left LD socket                    Right LD socket
 
1 plate triode 1                                     5
2 grid triode   1                                     1
3 cathode triode 1                                 2
4 heater                                                                                           3
5 heater                                                                                           4
6 plate triode 2                                                                                 5
7 grid triode 2                                                                                   1
8 cathode triode 2                                                                             2
9 Shield tied to pin 8 at the socket

 
Here you go... :)
 
2C51 / 396A / 5670 wiring guide for the LD
 
9 Pin socket                                 Left LD socket                    Right LD socket
 
1 heater                                                                                           3
2 cathode triode   1                                2
3 grid triode 1                                        1
4 plate triode 1                                       5
5 shield tied to pin 8 at the socket
6 plate triode 2                                                                                 5
7 grid triode 2                                                                                   1
8 cathode triode 2                                                                             2
9 heater                                                                                           4
 
Apr 3, 2014 at 4:16 PM Post #5,712 of 13,438
I just received my russian 6AS7 and playing it with LD 1 for now  just incase i blow something up. it works but i'm worried about the  tube base it's wobbly (both tubes i don't know if these is normal for these type of tube)it looks SEXY.

 

 

 
Apr 3, 2014 at 4:43 PM Post #5,713 of 13,438
Loving these C3gS tubes!
 
Finally got the shields removed thanks to Hypnos1's guide.
 

 
Apr 3, 2014 at 6:11 PM Post #5,714 of 13,438
I really like these tube photo-essays of yours.
beerchug.gif

 
It's good to know that someone actually reads this stuff. Thanks! :)
 
And continuing with E80CCs, I just came across a very interesting listing on eBay. A pair of 1957 Hamburg-made E80CCs. From one of the pictures, it is easy to read the production code: WK2 D7B. And again, the production code on my tube is WK3 45B.
 
Now this is very interesting...... The Hamburg tubes were manufactured two years, to the month, after my Eindhoven tube. But the change code on the Hamburg tube is "2" whereas the change code on my Eindhoven tube is "3". And so I wondered... why are the later Hamburg tubes an iteration behind my Eindhoven tube? My first thought was that it just took time for the latest changes to roll out from Holland. But on second thought, 2 years seems too long. Perhaps what this actually suggests is that by the middle 1950's the decision had already been made to cease the manufacture of this tube in Hamburg and consolidate all production in Holland, and eventually Heerlen. And therefore, it made good business sense to avoid spending the funds necessary to upgrade the Hamburg assembly line. And perhaps these 1957 tubes were among the very last to be made in Hamburg. 
 
Of course, I do not know, but sometimes it is fun to speculate about things that happened many years ago....
 

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