[warchild]

Quote:

The power / mains transformer has to deliver at least 6.3 volts @ 10 amps for these power hungry tubes.

 
The voltage is easy, I think but 10 amps is YOW! but apparently doable. Does this generate too much heat or buzz?

 

[john57]

Quote:

 
 
 
This is with a GZ37 rectifier
 

 
I hadent noticed any difference in sound between the
3DG4 @ $1.00 and the GZ37 @ $100.00 so I recommend
the 3DG4 but it doesn"t look as good.

Glenn,
 
Holly smokes I did not know much about your experimental amps. Personally I think that using the 6336 tube is a great idea and maybe less chance for the tube to pop, ping or arc over. By the way I still have the NOS " THE CHIEF" 3DG4 tube in its original box in storage. That tube will look good.

 

[Silent One]

My interest is heating up just like a 

tube!

 

[Neogeo333]

from what I've read the trick for a 6336 amp is to make a delay or slow start circuit for it because of the high current. Many have burnt lots of 6336 because it just draw too much when starting up. I hope Glenn already figured that out. I guess I will be stocking up on those 3dg4 if they sound equal to a gz37. Hell of a lot cheaper. One of the best 6336 tubes is the CSF Thomson 6336A different construction than the American version.

 

[Silent One]

I think my Sylvania 3DG4 cost $3... still cheep to me!

 

[john57]

Quote:

from what I've read the trick for a 6336 amp is to make a delay or slow start circuit for it because of the high current. Many have burnt lots of 6336 because it just draw too much when starting up. I hope Glenn already figured that out. I guess I will be stocking up on those 3dg4 if they sound equal to a gz37. Hell of a lot cheaper. One of the best 6336 tubes is the CSF Thomson 6336A different construction than the American version.

Neogeo,
 
It has been my experience that the 3DG4 is a very reliable tube. The 3DG4 can become very black inside like carbon but still works just fine. The 3DG4 does have low voltage drop with current as compared to some rectifier tubes.  3DG4 Tube voltage drop = 32V @ 350mA I think that having a good rated transformer is the key to handle the heater start-up current. It is usually the high voltage that could be delayed in some designs that I am aware of.

 

[GrindingThud]

Very very cool. I'm assuming this is an OTL configuration? You're giving me all kinds of crazy ideas for a build (or a buy if I can swing a kitchen pass).

New Experimental Amplifier

My initial goal was to make a amplifier that would sound good with
the lowest cost tubes. You can still get 6SN7s for $1.00 so this is the
amp with all 6SN7s 8 for outputs and one for driver + one 3DG4 rectifier.
Total Cost for tubeing was $9.00 for 6SN7s.....

Same Amplifier with 6AS7s for outputs
Anyone that has one of my OTLs know what this sounds like

To my suprize I tried 6336 for outpute because the power supply
can handle these current hogs.
These tubes walk all over 6AS7s power and bass is great

 

[2359glenn]

Quote:

from what I've read the trick for a 6336 amp is to make a delay or slow start circuit for it because of the high current. Many have burnt lots of 6336 because it just draw too much when starting up. I hope Glenn already figured that out. I guess I will be stocking up on those 3dg4 if they sound equal to a gz37. Hell of a lot cheaper. One of the best 6336 tubes is the CSF Thomson 6336A different construction than the American version.

 
Using a Rectifier tube instead of a SS rectifier is a slow start.
 
I will make your amp to accept a 3DG4 I wire the rectifier socket so if a 5 volt rectifier
is plugged in it will get 5 volts and if a 3DG4 is plugged in it will get 3.3 volts.
 
I tried a bunch of 6336 tubes and found that the Tung-Sol / Chatham tubes are no good.
had them arc over and blow up. They also have a different construction compared to
the others. They look similar to a 6AS7 construction. 

 

[john57]

Quote:

 
I tried a bunch of 6336 tubes and found that the Tung-Sol / Chatham tubes are no good.
had them arc over and blow up. They also have a different construction compared to
the others. They look similar to a 6AS7 construction.Glenn,
 

 
Glenn,
 
I noticed that the 6336 that looks like the 6AS7 is not reliable? There is a 6336A and the 6336B which seems to be more boxy looking as far construction goes.
I also found out that the 6336 just use metal plates and the 6336A and the 6336B are [size=11pt]zirconium[/size] graphite coated plates.
 
P.S. I again found out that the 6336A and the 6336B was commonly used in military power supplies for the Navy. I found a tip that using these tubes for the first time after all these years is to recycle the heater a few times like every half hour through the night before applying high voltage to reduce the chance of shorts.

 

[Neogeo333]

My experience was limited with the 6336 tube, when I had my LD MK6+ which was designed to use 6080 tube but saw in a Chinese forum that someone used 6336 in them and nothing blew up, so I took a chance and tried it on the MK6, nothing world changing but music seemed to sound more effortlessly if i remember correctly.  Then someone here mentioned that it could shortened the life of the amp and after 10 hours with them I pulled them out and never used again.  Ohh and four of the those suckers running it gets pretty hot.  Even hotter than my KT-120 tubes. 
 
There basically two revisions of the 6336 tubes if I remember, please correct me if im wrong.  The original 6336 and then the 6336A and B version.  Many say the the A and B are the same. 

 

[Xcalibur255]

Quote:

Glenn,
 
Holly smokes I did not know much about your experimental amps. Personally I think that using the 6336 tube is a great idea and maybe less chance for the tube to pop, ping or arc over. By the way I still have the NOS " THE CHIEF" 3DG4 tube in its original box in storage. That tube will look good.

I have been super jealous of the CHIEF ever since I saw your photo a long time ago. 

 

[Xcalibur255]

All the new amp builds look pretty amazing Glenn.
 
As I recall I talked with you once a long time ago about the 6336 tube.  We thought it might be possible to run it in the current OTL amp but you warned me we would be pushing the transformer pretty hard so I never actually tried it.
 
The fact that you can use the 6336 in the 8x6SN7 amp is pretty awesome.  A very flexible design with lots of possibilities.  The person who gets that amp is going to be a lucky guy. 

 
If you haven't you should try to get 6 6BL7 tubes that have the flat ladder type plates, I think they sound noticeably better than the 6BL7GTAs with the U shaped plates.  Harder to find though.
 
Tons of cool stuff, it puts a smile on my face to read about all of this.

 

[john57]

Quote:

There basically two revisions of the 6336 tubes if I remember, please correct me if im wrong.  The original 6336 and then the 6336A and B version.  Many say the the A and B are the same. 

Today was my first day I read up the 6336 tubes in detail. As far I could tell the 6336A and the B version was mostly the same except possibility that the B version which  may have been rated at a higher JAN vibration standard.

 

[rosgr63]

Very nice, Glenn, I like it, well done.

 

[2359glenn]

I dident say but the driver tube can be a 6SN7 or 12SN7 or 25SN7 / 1633 / 13D1
This allows for more driver tubes to be tried I was useing it with a Ken-Rad 1633 on the 25 volt setting