Little Dot Tube Amps: Vacuum Tube Rolling Guide
Feb 2, 2014 at 10:55 AM Post #4,891 of 13,448
  THANKS! so it will work without separate power adapter reason i asked the Bravo audio Ocean power adapter is 24V-1.5A i'am thinking to used that as power adapter for 6SL7 and i ordered the regulator as will.

 
A separate power adapter is not really necessary for 6SL7 tubes. They draw only 300 millamps and the LD can easily provide this much current. So you can connect pins 3 and 4 on one of your Vectors to pins 7 and 8 on your octal socket. 
 
But 6SN7 draw 600 milliamps and therefore a separate heater power supply is recommended. The Bravo adapter plus a voltage regulator should be perfect.
 
Feb 2, 2014 at 11:00 AM Post #4,892 of 13,448
So pin 7 and  8 will be disconnected from LD Right socket pin 3 and 4 and can you please let me know which pin should i connect the Positive and negative(PIN 7 or 8) from power regulator sorry for all these questions i don't have much knowledge in Electronics/Electricity Again THANK YOU!
 
Feb 2, 2014 at 11:04 AM Post #4,893 of 13,448
   
A separate power adapter is not really necessary for 6SL7 tubes. They draw only 300 millamps and the LD can easily provide this much current. So you can connect pins 3 and 4 on one of your Vectors to pins 7 and 8 on your octal socket.
 
But 6SN7 draw 600 milliamps and therefore a separate heater power supply is recommended. The Bravo adapter plus a voltage regulator should be perfect.

Since i have the regulator on the way and i have the power adapter on hand mind aswell used it.Thank You!
 
Feb 2, 2014 at 11:14 AM Post #4,894 of 13,448
  So pin 7 and  8 will be disconnected from LD Right socket pin 3 and 4 and can you please let me know which pin should i connect the Positive and negative(PIN 7 or 8) from power regulator sorry for all these questions i don't have much knowledge in Electronics/Electricity Again THANK YOU!

 
Fortunately, polarity does not matter. :)
 
Feb 2, 2014 at 11:29 AM Post #4,896 of 13,448
THANK YOU GUYS FOR YOUR HELP!
biggrin.gif

 
Feb 2, 2014 at 12:49 PM Post #4,897 of 13,448
I'll throw my 2 peso's in here as I know you guys just like hearing my wet blanket, err on the side of caution opinion...

When you shut off the LD there is still high voltage in the capacitors that takes a minute or two to discharge. This is why you still hear music after the amp shuts off and the tubes cool.

Yanking out tubes when the amp is immediately shut off will stress the board components unnecessarily.

I always turn the amp on without headphones plugged in, I allow it to warm up for a few minutes then with the volume at zero, plug my headphones in. When tuning the amp off I always bring the volume to zero, unplug my headphones and then turn the amp off. I wait 5 minutes before changing tubes, then repeat the above turn on sequence.

The less stress to the amp and my headphones, I feel should be taken into consideration. Call me OCD or anal retentive but I am not really interested in taking chances just to flip a $5 tube. I always test new tubes with crap heaphones, I have a pair of $9 JVC RX300's that I use.

This has been my opinion for this question and you know what they say about opinions... :D
 
Feb 2, 2014 at 1:50 PM Post #4,898 of 13,448
I'll throw my 2 peso's in here as I know you guys just like hearing my wet blanket, err on the side of caution opinion...

When you shut off the LD there is still high voltage in the capacitors that takes a minute or two to discharge. This is why you still hear music after the amp shuts off and the tubes cool.

Yanking out tubes when the amp is immediately shut off will stress the board components unnecessarily.

I always turn the amp on without headphones plugged in, I allow it to warm up for a few minutes then with the volume at zero, plug my headphones in. When tuning the amp off I always bring the volume to zero, unplug my headphones and then turn the amp off. I wait 5 minutes before changing tubes, then repeat the above turn on sequence.

The less stress to the amp and my headphones, I feel should be taken into consideration. Call me OCD or anal retentive but I am not really interested in taking chances just to flip a $5 tube. I always test new tubes with crap heaphones, I have a pair of $9 JVC RX300's that I use.

This has been my opinion for this question and you know what they say about opinions...
biggrin.gif

Better safe than sorry!
 
Feb 3, 2014 at 12:28 PM Post #4,899 of 13,448
Hi guys.
 
Just thought I'd butt in, even though I confess I haven't been joining the octal odyssey - to my shame! In my defence - and to my 'grand chagrin' that no-one else seems to have given them a try -  with a good many more hours on them, these C3gs have done incredible things for my MKIV SE (with 6N30P-DRs). I can honestly say the leap is not just that from 6HM5/6CS6 to some VERY good '6DJ8s', but from the stock 8100s - if not even greater!! And this holds true for EVERY piece of music I have been using for comparison these past many months. Can this be surpassed? Possibly... but...
 
Whatever, I can only hope y'all are experiencing the same joy that I now get from this humble machine.
 
Happy rolling, everyone...
 
Feb 3, 2014 at 12:42 PM Post #4,900 of 13,448
  Hi guys.
 
Just thought I'd butt in, even though I confess I haven't been joining the octal odyssey - to my shame! In my defence - and to my 'grand chagrin' that no-one else seems to have given them a try -  with a good many more hours on them, these C3gs have done incredible things for my MKIV SE (with 6N30P-DRs). I can honestly say the leap is not just that from 6HM5/6CS6 to some VERY good '6DJ8s', but from the stock 8100s - if not even greater!! And this holds true for EVERY piece of music I have been using for comparison these past many months. Can this be surpassed? Possibly... but...
 
Whatever, I can only hope y'all are experiencing the same joy that I now get from this humble machine.

 
Unfortunately, I suspect that many of us, myself included, are a bit daunted by the task of building a proper set of adapters, plus the cost of a pair of C3gs. Perhaps you should consider starting a cottage industry? Perhaps "C3gLD" would be a good name? lol :)
 
For sure, I can't help but wonder how these compare to the E80CC....
 
Feb 3, 2014 at 1:43 PM Post #4,901 of 13,448
  Hi guys.
 
Just thought I'd butt in, even though I confess I haven't been joining the octal odyssey - to my shame! In my defence - and to my 'grand chagrin' that no-one else seems to have given them a try -  with a good many more hours on them, these C3gs have done incredible things for my MKIV SE (with 6N30P-DRs). I can honestly say the leap is not just that from 6HM5/6CS6 to some VERY good '6DJ8s', but from the stock 8100s - if not even greater!! And this holds true for EVERY piece of music I have been using for comparison these past many months. Can this be surpassed? Possibly... but...
 
Whatever, I can only hope y'all are experiencing the same joy that I now get from this humble machine.
 
Happy rolling, everyone...

 
Can you post a pin out for your adapters if you haven't already?
 
Feb 3, 2014 at 2:55 PM Post #4,902 of 13,448
Gibosi.
 
I can fully understand the hurdles you mentioned - IF ONLY we had discovered these C3gs a while ago, before spending money exploring so many of the 6DJ8 family...we would still be less out-of-pocket! Ah...hindsight...Especially as I missed out on 8! tubes (used) at Christmas - can now kick myself REAL hard, they went for about $8 each if I remember rightly!! At that price I would have gladly made up some adapters and shared them amongst my fellow masochists, if only to check whether I am hallucinating re. my findings! But as I am sure I am NOT, I would love to share the magic I have been enjoying for a while now. Perhaps some more cheapies will appear at some time in the future...who knows? (Would love to know who got them and to what use - or rather in what). Then I could at least send them on the 'rounds', for people to compare - such as with your E80CCs, etc.
 
Ah well, we wait and see...live in hope, lol.
 
Feb 3, 2014 at 4:45 PM Post #4,904 of 13,448
I always turn the amp on without headphones plugged in, I allow it to warm up for a few minutes then with the volume at zero, plug my headphones in. When tuning the amp off I always bring the volume to zero, unplug my headphones and then turn the amp off. I wait 5 minutes before changing tubes, then repeat the above turn on sequence.
 

 
Actually, I don't deviate too much from this regimen. However, when I am doing A/B comparisons of two tubes, I probably wait about 2 or 3 minutes, rather than 5. Also, when rolling 6DJ8 tubes, I find that if I take the volume all the way to zero, there is a strong ground hum, so I take it down to around one or two. I do not experience this with any other tube and suspect it is due to parasitic oscillation as this is a known problem with 6DJ8.
 
Feb 3, 2014 at 5:05 PM Post #4,905 of 13,448
The other day, I received a 1953 Sylvania "Chrome Dome."
 

 

 
The eBay vendors often refer to any tube with top getter splash as a "Chrome Dome". However, it is my understanding that this is the tube people were looking at when the term "Chrome Dome" was coined. You will notice that virtually the entire bottle is "chromed". Further, the demarcation between the getter splash and clear glass is rather ragged and defuse. On most of the other tubes with top getter splash, that demarcation is crisper and straighter. Peering inside, I can see the same 3-hole black plates as the Sylvania 6SN7W, but no copper support rod.
 
Unfortunately, I have not spent much time with this tube, but in a quick A/B comparison with the metal-base Sylvania 6SN7W, I noticed a strong resemblance. While not exactly the same, it is quite similar, a slightly different shade of gray so to speak, and if you like that sound signature, I think you would also like this tube. I should note that a number of posters over on the 6SN7 Addicts thread rate this tube quite highly, in their top 5.
 

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