Ooooo....I could use all those 12SN7s I found in my stash the other night.

Quote:

Originally Posted by Silent One 

Pricing for the 12SN7 series certainly looks attractive. Will have to inquire.  If Glenn reads Head-Fi instead of the morning paper, then I won't have to...

 

 I filled out the Head-Fi survey the other day and laughed at the question about how many hours I spent on the site per week. I read it at home, work, school and will check my subs on my phone when I am away. *sigh*

So is that adapter to use in any amp? I assume the intent was for Glenn Studios amps.

It should be okay in other amps that use the 6SN7 too.

This is no doubt the smarter way to go about acquiring this particular type of tube, so I say to myself after spending way too much money on way too many 6SN7 tubes.

Quote:

Originally Posted by Xcalibur255 

It should be okay in other amps that use the 6SN7 too.

 

This is no doubt the smarter way to go about acquiring this particular type of tube, so I say to myself after spending way too much money on way too many 6SN7 tubes.

I bought a lot of 6SN7s before I even had an amp to use them. In the hoard I've alluded to I've found 60+ of them from different manufactures. I really need to catalog this stuff.

Quote:

Originally Posted by Silent One 

 

Your time on the site is valuable - always poised to make a contribution. I would think the adapter would work for any amp as specified (12SN7>6SN7). You've another amp in mind? I'm getting restless. I have a refund being processed (SB Touch) and the proceeds are to fund the "X" mod (and shipping). It's already been received and inspected. The payment is in the books! Apparently, someone in Accounts Payable is dilly-dallying. 

 

I feel the same can be said about you good sir!

Quote:

Originally Posted by Silent One 

 Just what kind of premium 12SN7 tubes are lurking inside your closet anyway?

I think I saw mainly Sylvania. As I mentioned above, I need to really take time to write down what is there.

  With the 12SN7 adapter you can also use the 12SX7GT as well. The 12SX7GT is considered to be the premium version of the 12SN7. The 12SX7GT has twisted heater wires that may give lower hum noise in the amp. The RCA gray glass 12SX7GT is supposedly one of the better tubes. I am getting a few Ray NOS 12SN7 tubes for $3 each. I should also be able to use the 14N7 tubes as well since I do have a 7N7 adapter if I wanted to. Voltage doubler are a trickier adapter to make because of the switching noise of the diodes and SMT capacitors may not do the job. Glenn then had to use an extra large socket to fit in the 1000uf capacitors to minimize the noise.   Since the adapter is extra large it will only work on amps that have some space between the sockets and the socket needs to be flush with the top panel with the adapter I have.

I am pleased Glenn solved the noise problem with the 12SN7 to 6SN7 adapters.

We talked about it last December, didn't take long for Glenn to sort it out.

http://www.head-fi.org/t/479031/6sn7-tube-addicts/1440#post_7961152

You are most welcome SO.

Another solution is to design an amp that can use either 12SN7 or 6SN7 tubes by means of a selector switch without the need of an adapter.

Glenn has put an EC(engineering change) on my older version of the amp to make it more resilient against shorts.  The 6.3v filament is now floating on 1/2 of cathode voltage which is 125v and the other cathode is at 25v. Which in turn means that the heater to cathode voltage has a net difference of 100v which is much lower that before as before to prevent dielectric breakdown between the heater and the cathode. My amp was designed for the Russia 6AS7/6N13S tube which can handle up to 300V between the heater and the cathode. Tubes like the 5998 and the 7236 can only handle 100V between the heater and the cathode otherwise the tube can short out which did happen. The cathode of the 6SN7 is run positive in respect to the other cathode.

My amp looks quite crowded now. Adding an selector switch for the 12SN7 and 6SN7 and add the voltage doubler or float the 12v line with a transformer change depending on space available in the amp are options. Only Glenn knows for sure. One advantage of an adapter is that I do not have to concern about remembering to switch back to the 6v when using the 6SN7 tubes. My adapter is ceramic base with gold plated pins and appears to be along the first that Glenn has built.

Quote:

Originally Posted by Silent One 

 

Your time on the site is valuable - always poised to make a contribution. I would think the adapter would work for any amp as specified (12SN7>6SN7). You've another amp in mind? I'm getting restless. I have a refund being processed (SB Touch) and the proceeds are to fund the "X" mod (and shipping). It's already been received and inspected. The payment is in the books! Apparently, someone in Accounts Payable is dilly-dallying. 

 

This adapter will not work on any amp the 6SN7 Filament has to be run on AC not DC and it will not work in Woo amps that have the two 6SN7s in series running off 12.6 volts. plus

the Woo sockets are recessed and this adapter will not fit.

   First you would have to know if your amp runs the 6SN7 off AC or DC before considering one of these.