Little Dot Tube Amps: Vacuum Tube Rolling Guide
Jun 8, 2014 at 3:41 PM Post #6,451 of 13,432
   
Hi sgb.
 
I did in fact post a photo tutorial - #5683 - which should hopefully help you. You can either leave the base loose, or glue it back on - you'll need a thick glue, and be careful it doesn't run down into the pins. Either way, you will need to make ABSOLUTELY sure the 'church windows' match up to maintain proper pin placement...I found the base could almost fit convincingly onto the pins in any order!
 
Hope all goes well...it'll look SO much better, lol!
 
Any questions/problems just let us know...will be back on tomorrow...
 
Cheers.

Thank hypnos. Might attempt it sometime in the future. Seems like a fair bit of effort though I do like to see tube glow :) Why do the tubes have the casing in the first place? does it help to keep them cool? I was apprehensive of trying these c3g's due to the rave reviews and didn't want to be disappointed though I'm glad you and others recommended them. Along with the 6sn7's this amp is in another league now. Just got my sylvania 1952 'bad boys' 6sn7's to arrive and I think I'm set and wont be buying tubes (for the LD MKIII anyway) ever again unless another incredible tube like the c3g gets discovered.
 
Jun 8, 2014 at 4:18 PM Post #6,453 of 13,432
Unfortunately my skills are more mental than physical. I have the manual dexterity of an elephant wearing mittens - hence my tube rolling being limited to the jumper-free variety...so far. I have been somewhat inspired, and will give it a go, though - and if the result is passable, I'll post pictures. I have a couple of ideas....

I managed to locate some Yugoslavian 6HM5's so I'll soon have even more unburnt-in tubes. Thanks for the tip. :beerchug:

The listening session with the AKGs and the Mullards did not go well. What I love about the AKGs is the detail they pick up but, right now, some of that detail is in the rough region which I think burn-in will smooth out. The same thing happened for the first couple of days with the stock tubes. I don't normally do this, but I think it may be time to dig out "pink-noise.wav"...

I'll give the line-out of the X3 a go sometime but it'll have to be something special to beat taking the X3 coax into the irDAC. (NB, I have used the line-out of the X3 elsewhere and I really wouldn't be surprised if it gives the irDAC a bit of stiff competition, but I have to at least pretend the irDAC was money well-spent - or isn't that the head-fi way? :wink: ).
The Coax Out from the X3 should be very nice into the Arcam for sure, I would have rather had an Optical on the X3, not for any specific sound difference from Coax, I just like Toslink cables... :)

Enjoy the 6HM5's when they arrive.
:beerchug:
 
Jun 8, 2014 at 4:24 PM Post #6,455 of 13,432
Newbie-alert. I've just bought a Grado RS1i and am thinking about a LD1+. Sorting through 400 + pages here is a little daunting. Would any of you give me some suggestions as a starting point?
 
Jun 8, 2014 at 4:35 PM Post #6,456 of 13,432
  Newbie-alert. I've just bought a Grado RS1i and am thinking about a LD1+. Sorting through 400 + pages here is a little daunting. Would any of you give me some suggestions as a starting point?

I'd start with this chart...
 
http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/1140#post_9392055
 
Jun 8, 2014 at 4:36 PM Post #6,457 of 13,432
The Coax Out from the X3 should be very nice into the Arcam for sure, I would have rather had an Optical on the X3, not for any specific sound difference from Coax, I just like Toslink cables...
smily_headphones1.gif


Enjoy the 6HM5's when they arrive.
beerchug.gif

I hear you. I still can't believe that something as "science fiction" as optical cables seemed when they first came out can now be matched by a bit of antenna cable. It just doesn't seem right.
 
Jun 8, 2014 at 4:41 PM Post #6,458 of 13,432
lol TD please explain your excitement over Reel to Reel :p

I am curious now..
I Have heard some great stuff back in the day on R2R systems, seeing that deck in the background brings back fond memorys from the repair shop of torque meters, test tapes, head alignments... Stuff I haven't seen or used in years, when someone brought in a R2R deck for service, one took pride in tuning it up top notch as you knew the music was appreciated and not just background noise.

That's all... I havn't heard one in years. :D
 
Jun 8, 2014 at 4:50 PM Post #6,459 of 13,432
  I'd start with this chart...
 
http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/1140#post_9392055


thanks!
 
Jun 8, 2014 at 5:47 PM Post #6,460 of 13,432
Just a quick progress report, and I'll stop spamming the thread for a while. I put 4 hours of pink noise through the Mullards and things are improving nicely. I don't think the AKG K702s will need any more detail, after all, and I believe that the AKG/Mullard combination will be very much to my taste. Still plenty of improvements to come though (I think). I'll get a bit more time on these tubes then I'll try the Voskhods. I've a feeling that they will work well with my HD600s.

Then I can do it all over again with the 6HM5s :)

At least it's cheaper than buying a whole new amp to tweak your sound :)
 
Jun 8, 2014 at 6:55 PM Post #6,462 of 13,432
  Hi guys. Seen as the 7 pin extenders/socket savers were lost in transit I decided to remove the brass rings. After much deliberation I got them off and now the 6sn7's and c3g's fit and no extenders are needed. Now I'm just wondering how people have removed the metal casings on the c3g's? Thought I would ask in advance just in case I break the tubes removing them.

 
These tubes were designed to last 10,000 hours in their little metal cans. The metal casings were designed to shield these tubes from electrical interference as they were typically used in noisy environments. So it is perfectly fine to leave them in their cans forever. The only reason to run them "nude" is aesthetic. :)
 
Jun 9, 2014 at 12:31 AM Post #6,463 of 13,432
Here is another update on the great sounding LD MKIII Raytheon 6832 subminiature setup. In anticipation of receiving another 5A voltage regulator for the left 6080 power tube, I cobbled together a separate power supply using my old 2A voltage regulator to test everything out.
 
Since I cannot run the second 6080 yet, I put in a Westinghouse 12SN7GT in the left socket. Previously, when I used this tube as a driver, it distinguished itself as very good sounding. The one 6080 I have installed runs very hot (I have a small burn mark mark on my thumb to prove it). I decided to change the external cooling fan from 3" to 4" for greater air flow.
 
This fan also came from my parts bin of old computer parts. It makes a little whining noise, but the music drowns it out. For the second PS I found an old laptop PS rated 19V/2.6A. The inexpensive extenders have an unexpected benefit - they are not deep enough that the pins go all the way down, leaving a small gap. There is enough space to touch the the voltage meter probes to pins 4&5 and get an actual in vivo reading of the voltage with the tube in place and the PS plugged in. It is easier to do this before inserting the entire tube assembly into the LD sockets.
 
Close-up of the gap:

 
 
The three musketeers shooting electrons:
.
 
The two voltage regulators in action. Although indicated 7V and 12.5V, the actual measurements at the tube pins are 6.3V and 12.6V.

 
Bought some inexpensive heat shrink tubing that is supposed to shrink to half the thickness when heat is applied. Since I do not have a heat gun I used a cigarette lighter to shrink the tubing. The trick is to hold the flame some distance from the tubing and watch it shrink. Stop before the heat shrink turns burnt hot dog color (right side of wire).

This is an experiment in joining two wires without solder. I put two wires side by side and slipped the heatshrink tubing over the two pieces, then heated it.

The red section shows the heat shrink joint - seems to be holding fine.
 
Coming back to the three tube set-up - sounds very good. The bigger fan keeps the amp cooler.
 
Have fun!
 
Jun 9, 2014 at 10:04 AM Post #6,464 of 13,432
Jun 9, 2014 at 10:11 AM Post #6,465 of 13,432
  I manage to get a pair last month from vacuumtubes.net also ,and got a Chatham 6AS7G this morning from my tube guy at the flea market but even better than that i got a pair of Chatham's 2399 when i got the Woo and if you know the price these go for ,im very happy about that because i wouldnt pay that kind of money for those tubes to start with .So i should be  good for awhile but they always pop up somewhere And of course everybody knows   so there you go                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
                                                                                                                  
                                                                                                                 

 
OMG! mikelap...looks like you struck gold TWICE, you lucky b******! Sure wish I had a flea market like that near me, lol...(don't see many valves - ie tubes - in such places here in the UK, more's the pity).
 

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