Little Dot Tube Amps: Vacuum Tube Rolling Guide
Feb 11, 2014 at 9:55 PM Post #4,981 of 13,434
Probably some truth that people have found some great tubes and are busy listening to them. In addition, AFB who is one of the main contributors is abroad - I think he said Japan, and we have not heard from him in a while.
 
Another thing that surprises me are that a number of people participate regularly and suddenly disappear. Perhaps they switched to a different type of amp or gave up on tubes - who knows?
 
Acapella 11 - we miss you.
 
SonySlave - what's up?
 
inphu510n: any good deals on tubes?
 
Hypnos1 -  what's going on?
 
John57 - did u ever get to clean up your desk?
 
And the mysterious (and ambitious) thread starter - Dept_of_Alchemy: What do you think about where we are now? No more Pentodes, Triodes, Triode/Diodes or Heptodes. Only glorious Dual Triodes.....
 
Bitten by the vacuum tube bug:
 
lightbug.jpg

 
Oh no - another one!
 
il_fullxfull.90183684.jpg

 
Feb 11, 2014 at 10:10 PM Post #4,982 of 13,434
Although lately all my tube rolling has been going on with my Bottlehead Crack! :L3000:
Nice!
That was one of my first choices, after the Speedball upgrade and Shipping / Duty to Canada it overshot the budget by quite a bit... The Bottlehead didn't have any WAF either... :D
 
Feb 11, 2014 at 11:15 PM Post #4,983 of 13,434
  http://www.youtube.com/watch?v=pShuE09VsjI              

Ahhhhhh... that's enough to make my drive forks into my ears!
eek.gif

 
Feb 12, 2014 at 4:32 AM Post #4,984 of 13,434
Hello guys, as the thread kind of slowed down, i would ask for help on my new project.
What i planned was an adapter for my ld mkiii that allows me to use 6sn7 as power tube and c3g as driver tube.
I did never build any adapter, no experience.
Do you think it is possible for an soldering noob like me to build this adapter?
I highly doubt that i could solder the pins in the right layout...

Another question, what tube adapters or...... do i need to buy to connect to the sockets of the mkiii in driver and power section?

Thank you guys!
Great thread!
 
Feb 12, 2014 at 10:04 AM Post #4,985 of 13,434
Hello guys, as the thread kind of slowed down, i would ask for help on my new project.
What i planned was an adapter for my ld mkiii that allows me to use 6sn7 as power tube and c3g as driver tube.
I did never build any adapter, no experience.
Do you think it is possible for an soldering noob like me to build this adapter?
I highly doubt that i could solder the pins in the right layout...

Another question, what tube adapters or...... do i need to buy to connect to the sockets of the mkiii in driver and power section?

Thank you guys!
Great thread!

 
To use 6SN7 as power tubes, you can purchase a ready-made adapter:
 
http://www.ebay.com/itm/1pc-convert-tube-socket-6CG7-to-6SN7-/221065463320?pt=US_Amplifier_Parts_Components&hash=item3378874618
 
Or more simply, you can use 6CG7 and 6FQ7 tubes, which are plug and play. However, you might find that your current power tubes are better....
 
I have never seen a ready-made C3g to 6AK5 adapter, and making one is not trivial. The C3g has an 8-pin base and the 6AK5 has a 7-pin base, so you will have to figure out how to make that translation. To my knowledge, the only person who has done this is Hypnos1 so you might want to contact him.  
 
But there is another option.... Like the C3g, the E80CC is a very low distortion tube. But in fact, when you strap the C3g as a triode, the distortion increases to a level comparable to a 6SN7. The E80CC, being a dual triode, doesn't need to be strapped and as a result, has lower distortion than a strapped C3g. Further, using a E80CC in our Little Dots is easier. All you need is a 9-pin socket and an external heater power supply, similar to a 6SN7.
 
Anyway, whatever you decide, good luck and have fun! :)
 
Feb 12, 2014 at 10:53 AM Post #4,986 of 13,434
  Audiofanboy.
 
 Yep, you certainly were right to throw C3gs into the mix, after gibosi's related findings. My heartfelt thanks go to you both; Yamamoto, and JAC Music for pushing me in that direction. Even straight out of the box they were amazing, and now with a good few hours on them I still cannot believe what they have done for this modest not-so-little amp (ie the MKIV SE).
While I am giving thanks, I for one would also like to say grazie to the founder of this thread - Dept of Alchemy - and Acapella 11, who contributed so much to this thread and is sorely missed (where are you now?!). I would have loved to hear their views on what has been achieved these past months. Thanks also to all the other regulars, who have made this thread such an education AND joy (not to mention the "tube-roller widow" indoors!!)...
 
Mordy, and anyone else interested, here is the pin layout for said C3g :
 
                     C3g               6AK5(et al)
                    
                     Pin                Pin
 
                    1&8 - H         3&4 - H
                       2  - G3(s)    
                       3  - P            5   - P
                       4  - G2(s)     6   - G2(s)
                       5  - K            2   - K,G3(s)
                       6  - G1(s)     1   - G1
                       7  - K            7  - K,G3(s)
 
As advised by gibosi, I linked C3g pins 2 & 7, to eliminate a floating grid.
 
Having connected all corresponding pins, everything is working perfectly (so far!) and trust there shouldn't be any nasty surprises further down the road...
 
Cheers everyone, and happy rolling...

 
This is the c3g pinout post
 
Feb 12, 2014 at 11:09 AM Post #4,987 of 13,434
  Mordy, and anyone else interested, here is the pin layout for said C3g :
 
                     C3g               6AK5(et al)
                    
                     Pin                Pin
 
                    1&8 - H         3&4 - H
                       2  - G3(s)    
                       3  - P            5   - P
                       4  - G2(s)     6   - G2(s)
                       5  - K            2   - K,G3(s)
                       6  - G1(s)     1   - G1
                       7  - K            7  - K,G3(s)
 
As advised by gibosi, I linked C3g pins 2 & 7, to eliminate a floating grid.

 
I can see a very crude, but easy way to do this with two 8-pin breadboard sockets and two Vector 7-pin test sockets:
 
Purchase two 8-pin breadboard sockets for the C3gs. In each socket, tie pins 2 and 5 and 7 together, which straps Grid 3 to the cathode. And then tie pins 3 and 4 together, which straps Grid 2 to the anode. And then route pins 3 (anode), 5 (cathode) and 6 (grid) in each of these sockets to the corresponding pins in the Vectors plugged into your LD.
 
Edit: And don't forget about the heaters! :)
Edit2: It is not necessary to tie pins 5 and 7 together, as they are tied together inside the tube.... 
Edit3: Correction: 8-pin loctal breadboard sockets
Edit4: More corrections....
 
Feb 12, 2014 at 3:09 PM Post #4,988 of 13,434
   
I can see a very crude, but easy way to do this with two 8-pin breadboard sockets and two Vector 7-pin test sockets:
 
Purchase two 8-pin breadboard sockets for the C3gs. In each socket, tie pins 2 and 5 and 7 together, which straps Grid 3 to the cathode. And then tie pins 3 and 4 together, which straps Grid 2 to the anode. And then route pins 3 (anode), 5 (cathode) and 6 (grid) in each of these sockets to the corresponding pins in the Vectors plugged into your LD.
 
Edit: And don't forget about the heaters! :)
Edit2: And it may not be necessary to tie pins 5 and 7 together, as they are likely tied together inside the tube.... 
Edit3: Correction: not 7-pin breadboard sockets, but 8-pin (loctal if you leave the metal cases on, EU 8-pin otherwise....)

 
Hi gibosi, mab and collectoR13.
 
Many thanks g and m for referring cR13 to my previous posts, and sorry cR13 for not responding sooner...had spent 40mins this afternoon composing a long post, just for it to be trashed when I tried to add a link to a video on youtube, which I thought y'all might find interesting....I was not best amused, to say the least! So I shall try to see how I'm supposed to do it correctly this time...
 
Gibosi : lots more 'bits 'n pieces' but yes, safer for someone not confident in adapter-making land...such a shame.
Was interested by your instruction to tie C3g's pins 3 and 4 together. I routed #4 to LD's #6...can you enlighten me - is it to do with how the LD socket itself is wired? I have had no adverse effects whatsoever....And yes, it appears from the tube data that pins 5 & 7 are linked internally.
 
cR13 -  My advice  would be - if you already have said C3gs - to follow gibosi's idea first, then practice having a go at putting together some adapters yourself using a 'dummy' 8-pin, bending some solid 1 or 1.2 mm wire through a drilled disc (not metal, of course!!) that corresponds to the base of a 7-pin tube, and routed as per the pin-layout posts - but you MUST be sure of the pin numbering, both at the C3g and the disc...just remember that when viewing the pins from below, they run with #1 to the left, then clockwise. The solid wire then becomes the lower pins, of course, which has got to be far better than using a cut-off base from an old tube IMHO. Then you would need to seal and enclose the innards, however you wish. Needless to say, you MUST also make sure that no bare wire can possibly touch another (or anything else metal)...or...BOOM!
I must admit this is a tall order for a noob - but then so was I before I joined this thread. Only through reading the many posts of these past months, with the invaluable advice/knowledge freely given by so many great guys (no gals?!), plus practice (not to mention a wee bit o' courage/fright?!) have I managed to make a little progress in this field. But if you are still not confident in such a venture, you would be wise not to go this route...Whatever, good luck with anything you try...
 
Feb 12, 2014 at 3:12 PM Post #4,989 of 13,434
Thank you very much guys!
I would like to follow the way gibosi mentioned with c3g...
But what kind of adapter should I buy to plug into the ef95 sockets?
And i would like to keep it as simple as possible, i want a clean look like artsi achieved with his adapter..


And the readymade 6sn7 adapters are unfortunatly not shipping to germany... (and quite expensive lol)


So my main problem is, i dont know which parts to use for what and how i could put them into a clean case..
 
Feb 12, 2014 at 4:11 PM Post #4,991 of 13,434
Hi, I just received my 6SN7 tube and i would like to know if i need to modify the adapter for 6SL7 or adjust the voltage on my external Power supply?I'am currently running 6SL7 with externel PS(driver Tube).
 
Feb 12, 2014 at 4:14 PM Post #4,992 of 13,434
  Probably some truth that people have found some great tubes and are busy listening to them. In addition, AFB who is one of the main contributors is abroad - I think he said Japan, and we have not heard from him in a while.
 
Another thing that surprises me are that a number of people participate regularly and suddenly disappear. Perhaps they switched to a different type of amp or gave up on tubes - who knows?
 
Acapella 11 - we miss you.
 
SonySlave - what's up?
 
inphu510n: any good deals on tubes?
 
Hypnos1 -  what's going on?
 
John57 - did u ever get to clean up your desk?
 
And the mysterious (and ambitious) thread starter - Dept_of_Alchemy: What do you think about where we are now? No more Pentodes, Triodes, Triode/Diodes or Heptodes. Only glorious Dual Triodes.....
 
Bitten by the vacuum tube bug:
 
lightbug.jpg

 
Oh no - another one!
 
il_fullxfull.90183684.jpg

 
WOW mordy, LOVE those bugs - they look how I feel after many hours of analysing/evaluating/comparing etc. etc. Not to mention frustrating indecision! Are we all certifiable, or what?!
 Addiction has a fascinating array of elements and emotions...and would we have it any other way? I think NOT!
 
Yes, I have been quiet. And yes, it's because I continue to be blown away - still - by my C3gs, in a way I have never encountered before. I could swear the LD (MKIV SE at least) was made for these beauties - which is rather surprising, as in my search to gain more info on said tubes it appears that even aficionados have had problems getting the best out of them, in their high-end set-ups. And yet this humble machine hasn't encountered the slightest hiccough, even after many 15+ hour sessions. On the contrary, they have continued to get better and better.
I suspect they have been helped by my minimising connections from the tube pins to LD - ie mechanically attached and soldered 1.2mm silver wire (soft-annealed), basically acting as extended pins. A bit fiddly but, I believe, well worth it...
 
And so, as I believe I would have to spend BIG bucks for only little gain (which I am loathe to do in any area of life), I think this is where I shall be happy for a very long time.
 
Anyway folks, in my search I came across a mind-blowing video of a tube set-up like no other I have come across, and which you might find interesting/amusing. It is not a head-amp, but as a part of the 'beast' he has used C3gs, which must say something for them, methinks...
 
http://www.youtube.com/watch?v=dZ0N1g-kH1M
 
 
Oh dear, wrong again - still haven't managed a clickable link, but at least I've managed an address! Will try again - but AFTER I have posted this!!
 
Edit. Well what d'ya know - the link IS clickable when submitted...yipeee!
 
Feb 12, 2014 at 4:20 PM Post #4,993 of 13,434
Hi I luvmusic2,
 
The 6SL7 and the 6SN7 use the same adapter, but the 6SN7 draws more power, and you need and external power supply. The voltage is the same for both the SL and SN tubes, 6.3V.
 
So, in your case, it's just plug and play - you do not need to make any changes since you already are using the external PS.
 
IMHO, the 6SN7 is a better tube for the LD amps. Whatever the 6SL7 has, the 6SN7 has more of ...
 
Good luck listening!
 
Feb 12, 2014 at 4:22 PM Post #4,994 of 13,434
  The 6SL7 and the 6SN7 use the same adapter, but the 6SN7 draws more power, and you need and external power supply. The voltage is the same for both the SL and SN tubes, 6.3V.
 
So, in your case, it's just plug and play - you do not need to make any changes since you already are using the external PS.
 
IMHO, the 6SN7 is a better tube for the LD amps. Whatever the 6SL7 has, the 6SN7 has more of ...
 
Good luck listening!

THANK YOU! Now it's time for me to switch the tube.
 
Feb 12, 2014 at 4:44 PM Post #4,995 of 13,434
Just a reminder to anyone using Vector adapter becareful when handling it while it's installed on your amp.I thouht i turned off my amp but it turned out i forgot to do so, when i grab the adapter don't know which part i touch and i got shock not a good experienced.Dumb me....
 

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