Tube Rolling w/Crack

Dr. Toobz · 751987

0 Members and 1 Guest are viewing this topic.

Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1200 on: July 06, 2015, 09:46:52 AM
Hello,

Just completed my crack and its working well!

The tubes that were in the kit work very well....

On the small tube there is a very faint 12AU7 but no manufacturer id that can be actually read etc..

The power tube is a really big fat bottle type of old RCA tube. But I dont see anything on it that would tell me what it really is.

Is there anyway to tell from the pictures or the order what this tube is?

Thanks in advance!

Please note I am very happy with them!!!! Just wanted to know what they are for future ordering and tube hunting! (lol).

« Last Edit: July 06, 2015, 09:48:49 AM by adydula »



Offline Strikkflypilot

  • Sr. Member
  • ****
    • Posts: 459
  • Shellac fiddler
Reply #1201 on: July 06, 2015, 11:00:51 AM
RCA 6AS7G

Home system:
Sources: Ibasso DX90, Google Chromecast Audio optical out
DAC: Schiit Gumby
Amp: Bottlehead Mainline
http://bottlehead.com/smf/index.php?topic=7463.0
Phones: HD800S

Office:
Sources: Iphone/ Ipod
DAC: Dragonfly Red+Jtrbug
Amp: Crack/Speedball heavily modded
Phones: HD580,HD600 grilles


Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1202 on: July 06, 2015, 11:31:22 AM
Thanks!! for that 6AS7G.....awesome...I like its "shape" better than the straight bottles and I was indeed suprised when I saw it in the kit!! I hope I can find these somewhere!

Thanks Again!!

It is appreciated!
Alex



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #1203 on: July 06, 2015, 12:01:01 PM
Holy crap Adydula bought a valve amp!   Welcome to the dark side :)

If you want to get all anorak about it you can look up the date codes on that tube too, http://pax-comm.com/rcadates.pdf  If i'm not mistaken BM = April 1967

If you post up some clear pics of the 12au7 somebody may be able to tell you exactly what that is too..

M.McCandless


Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1204 on: July 06, 2015, 02:09:47 PM
Hello!

Ha! Dark Side.... seeing how I just turned a young 66yrs old, I grew up with tubes and all there worst and went thru several tube amps in the last few years and none of them really stood out to me compared to other SS amps.

I guess I got bored and wanted to build something and the Beyer T90s have many people recommending this particular amp for their pairing.

Well sir I am really amazed at how good this amp works with my T90's....I have not heard anything better so far..its really a pleasure to listen and I am finding myself spending way too much time listening once again!

I found several 6AS7G tubes in EBay etc for approx.$25 - $50 etc....

Today I put the first coat of minwax on the case.....

I also experienced one of those tube worts... listening today I kept hearing a low high pitched hum / squeal and it was the power tube doing a resonance dance, a slight tap on the bottle and it went away.... and I am sure it will come and go... just one of the things I love about tubes!!! LOL.

Even with these minor idiosynchrocies....this amp is worth the end result.... just absolutely wonderful music!!

Even my old crappy bright Chicago cd's sound wonderful... Eva Cassidy is like unreal....

Nice to see you here!

Alex

 



Offline Strikkflypilot

  • Sr. Member
  • ****
    • Posts: 459
  • Shellac fiddler
Reply #1205 on: July 06, 2015, 08:01:15 PM
Youre welcome:)

Home system:
Sources: Ibasso DX90, Google Chromecast Audio optical out
DAC: Schiit Gumby
Amp: Bottlehead Mainline
http://bottlehead.com/smf/index.php?topic=7463.0
Phones: HD800S

Office:
Sources: Iphone/ Ipod
DAC: Dragonfly Red+Jtrbug
Amp: Crack/Speedball heavily modded
Phones: HD580,HD600 grilles


Offline Colin

  • Jr. Member
  • **
    • Posts: 34
Reply #1206 on: July 09, 2015, 11:03:18 AM
Is 6520 the same tube with 5998? And how about Russian 6N13S/6H13C tube? Who know about this tube(6N13S/6H13C) sounding?



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #1207 on: July 09, 2015, 12:04:59 PM
6520 is a 6AS7G variant with better specs, you can of course use them.  Some of them even have the same plate structure as a 5998.

6H13S is a very nice tube too, probably the best bang for your buck of them all.

M.McCandless


Offline Nathan

  • Full Member
  • ***
    • Posts: 204
Reply #1208 on: July 10, 2015, 02:17:49 PM
Just got one- pretty inexpensive and in great shape. While I like the Tung Sol 5998 better, this is an easy tube to live with too-

Crack/Speedball, SEX 2.1/C4S, Bryston BHA-1

Sennheiser HD600/Cardas cable, Beyerdynamic T1 2nd Gen, Hifimam HE560/Hifiman balanced cable


Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1209 on: July 13, 2015, 11:05:58 AM
I am a fairly new Crack builder/owner and have gone thru many amps, both SS and tubes..... the Crack is indeed a very special amp that really plays very well for me with a set of Beyer T90's. 250 Ohms.

I can't tell what the stock 12AU7 is, there aren't any discernible markings on it but it sounds really great to me. The power tube is the coke bottle RCA and I believe its a 6AS7G.

I bought a $12 12AU7 JJ Electronics from www.boiaudioworks.com this is a place I have bought several tubes from great to deal with and great shipping and the tubes have always come to me well packed and fast, I think there in Tempe AZ. (note I have NO vested interest in them just an FYI and another source for tubes).

I have only listened for a few hours with the JJ but its absolutely a stellar performer, I have a Salk Demo CD that has some really extreme and well mastered flacs and they sound just marvelous...

I would NOT hesitate to use a JJ 12AU7, only $12 for a matched triode tube!

Waiting on my speedball upgrade!

All the best
Alex
« Last Edit: July 14, 2015, 05:35:12 AM by adydula »



Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1210 on: July 14, 2015, 06:06:08 AM
I looked at the 12AU7 that came with the crack, its has a 12AU7 in a octagon shaped label/box. Don't see any dots or anything else on the tube. On the bottom of the tube where the pins come out in the middle of the bottom glass inside the circular pins is the letter "N".

Does this mean anything, I assume this is a RCA tube, its not a clear top.

Alex
« Last Edit: July 14, 2015, 06:08:14 AM by adydula »



Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1211 on: July 14, 2015, 07:23:30 AM
I just got a RCA 6AS7G tube with Made in USA and the number "352" any idea on how to tell the date from this?

Alex



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #1212 on: July 14, 2015, 08:05:59 AM
With a lot of american tubes that have 3digit codes, the first digit is the year, the following two digits are the week number which would imply 52nd week of 1953. But i may be wrong about that...

M.McCandless


Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #1213 on: July 14, 2015, 08:08:30 AM
An octagon shape around the part number is usually an indication of RCA.

M.McCandless


Offline adydula

  • Sr. Member
  • ****
    • Posts: 279
Reply #1214 on: July 14, 2015, 08:41:54 AM
I think your correct. I got the orignal box it came it and it has a R-CB 16 and (1-49) on the top flap of the box where you open it up. This looks like the timeframe the carton was most likely made. It even smells like a 1950's box!!

I have an old Knight tube tester and it tested very well.

Been playing it for an hour seems ok fine for a good price compared to all the other high dollar stuff thats out there!

Alex