[Gilliboy82]

I will suggest a couple, and I am sure others have more to add.

6AV6 (and 6AT6 and 6AQ6) These are easy to mod, just cut off pins 5 and 6 and use the EF92 setting. The best tubes are those with a box-like structure (a box getter) on top of the mica:

http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/3285#post_9859647

6HM5 / 6HA5 / EC90

No mods required. Use the EF95 setting. You want to avoid the short squat tubes that look like the typical 6AK5,

http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/3300#post_9862250

http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/3045#post_9828452

Hello,

I tried to mod the 6AV6 by cutting off pins 5 and 6 and use the EF92 setting. But I hear nothing coming from my little dot 1+. It is dead silent.. Do I something wrong?
I also covered the empty pin 5 and 6 with some masking tape.

 

[TrollDragon]

Hello,

I tried to mod the 6AV6 by cutting off pins 5 and 6 and use the EF92 setting. But I hear nothing coming from my little dot 1+. It is dead silent.. Do I something wrong?
I also covered the empty pin 5 and 6 with some masking tape.

my guess is you cut off the wrong pins or don't have them plugged in correctly.

 

[Gilliboy82]

my guess is you cut off the wrong pins or don't have them plugged in correctly.

Pin 5 and 6 , you count from left to right beginning from the wide open space and you put them like all other tubes in the amp. Strange...

 

[barbazz]

Could be the case you clipped too close to the glass and somehow break the vacuum?

 

[Gilliboy82]

Could be the case you clipped too close to the glass and somehow break the vacuum?

That's not the case. The tubes don't light up, nothing..

 

[warp2600]

That's not the case. The tubes don't light up, nothing..

maybe you clipped the wrong pins. Can you post a pic?

 

[TrollDragon]

That's not the case. The tubes don't light up, nothing..

If the tube is not lighting up then you definitely counted from the wrong side and cut off one of the filament pins. Have a look through the glass and you will be able to see where the filament wires come through the glass at pins 3 & 4.

Also with 2 pins missing it is very easy to plug these in improperly as there is no index anymore.

 

[mordy]

If the tube is not lighting up then you definitely counted from the wrong side and cut off one of the filament pins. Have a look through the glass and you will be able to see where the filament wires come through the glass at pins 3 & 4.

Also with 2 pins missing it is very easy to plug these in improperly as there is no index anymore.

If the tube is not lighting up then you definitely counted from the wrong side and cut off one of the filament pins. Have a look through the glass and you will be able to see where the filament wires come through the glass at pins 3 & 4.

Also with 2 pins missing it is very easy to plug these in improperly as there is no index anymore.

Based on memory (hope I remember correctly):
When I did the “surgery” on the tube pins I always had to make sure that I counted the right pins by holding the tube upright and then looking at the pin pattern on the bottom.
If you turn the tube upside down and look at the pins and count it will come out wrong.

 

[Gilliboy82]

Based on memory (hope I remember correctly):
When I did the “surgery” on the tube pins I always had to make sure that I counted the right pins by holding the tube upright and then looking at the pin pattern on the bottom.
If you turn the tube upside down and look at the pins and count it will come out wrong.

Is it possible i used the wrong tape to cover pins 5 and 6? I used some thin tape, no special antistatic, isolating tape. Om really sure i've cut the right ones because i held the tube in it's standing position and counted clockwise beginning from the biggest space between the pins.

 

[barbazz]

Check this picture @MIKELAP posted sometime ago. That's my cheat sheet when there's a need to clip pins.

Original post: https://www.head-fi.org/threads/little-dot-tube-amps-vacuum-tube-rolling-guide.563884/post-9967383

 

[Gilliboy82]

Check this picture @MIKELAP posted sometime ago. That's my cheat sheet when there's a need to clip pins.



Original post: https://www.head-fi.org/threads/little-dot-tube-amps-vacuum-tube-rolling-guide.563884/post-9967383

 

[Gilliboy82]

That's exactly where I clipped the pins. I saw that image too.

 

[Gilliboy82]

I rechecked and i cut the wrong ones indeed because this picture has been taken from another angle than i thought. So it's bye bye to try the Sylvania 6av6.. sooo pity. Do the 6ah6 have the same mod? I can have the Raytheon 6ah6 but are they equally good to the Sylvania?

 

[gibosi]

I rechecked and i cut the wrong ones indeed because this picture has been taken from another angle than i thought. So it's bye bye to try the Sylvania 6av6.. sooo pity. Do the 6ah6 have the same mod? I can have the Raytheon 6ah6 but are they equally good to the Sylvania?

As best I can recall, this mod only works on 6AV6, 6AT6 and 6AQ6. These are double diode-triodes. The 6AH6 is a pentode.

And unfortunately, the 6AH6 will not work without a special adapter.

 

[TrollDragon]

I rechecked and i cut the wrong ones indeed because this picture has been taken from another angle than i thought. So it's bye bye to try the Sylvania 6av6.. sooo pity. Do the 6ah6 have the same mod? I can have the Raytheon 6ah6 but are they equally good to the Sylvania?

I cut off the wrong pin on one of mine but managed to solder another pin back in place to correct the mistake. It might be worth a try instead of trashing the tubes, you can use the pin you snip from the proper pin to solder onto the missing one.Tin quickly and don't use a lot of heat as the glass might crack.

The tube worked for me but in the end it was all for naught as I didn't like the sound from 6AV6/6AT6 tubes.