PI tube question

[menace2u]

Hamtone just hit the LOTTERY!!!!!!!!!

[Hamtone]

Unfortunately the rca's were no good. But the telefunken in v1 is ridiculous. Only problem with it is, it is souch touch sensitive it really shows my sloppy playing. I put the mullard ax7 in the pi and that really makes the amp blossom. The mullard is a bf something something, the screen print is worn. There is another mullard which turned out to be an au7 that I put in my tube driver which smokes any ax7 and at7 I have ever had in it. There's also an amperex which was good in v1 but nothing like the telefunken. Again with these tubes I found another increase in volume and high end clarity.. My ears actually hurt and I did not turn the amp up. I definitely will be getting a 4x12 to enhance the low end.

I will still tale some snaps j
ust for the sake of them being old tubes.

[Hamtone]

I wonder if what i am hearing is an increase in presence giving the impression of it being louder Its certainly a high end clarity that has improved with these tubes over the nos ones I had in it before.

[OldSchoolDave]

I wonder if what i am hearing is an increase in presence giving the impression of it being louder

Could very well be.

With the same power tubes, output should be roughly the same (when maxed, that is).

Dave

[ak-47]

While on the subject of tube lotteries...

I picked this bunch up last week for about $15US / €11Euro. I know some of the types and their uses but not all if anyone cares to enlighten me?

From left to right:

PC86 521137 (any ideas what this is?)
Motorola 12AX7A
Ei Yugoslavia PCH-200
RFT PCF802
Motorola 12AX7A
Mullard EF89 (used in tv’s?)
Mullard M8162 12AT7WA/WB CV4024 KB/D x3 pieces (yeah... those ones )
Mullard PF86

[OldSchoolDave]

If flashing is an indication, those Motorolas are pretty well used up. But, you got MORE than your money's worth out of the Mullard M8162's.

Dunno about the other species. The screened plates on the EF89 are kinda cool.

Dave

[ak-47]

Thanks Dave! I can't wait to try my mullards out in P1 (that is the best place huh?)

Do I understand right that if the motorlas flash on startup they are pretty toasted? Or do you mean they might be bad by your visual inspection?

[OldSchoolDave]

I can't wait to try my mullards out in P1 (that is the best place huh?)

Absolutely! You'll be glad you did .

Do I understand right that if the motorlas flash on startup they are pretty toasted? Or do you mean they might be bad by your visual inspection?

Sorry - I was not talking about power-up flash. I was referring to the silvery flashing at the top of the tube. It's pretty transparent on those Motos. Some manufacturers exhibit less flashing than others, but those are thin and the edges are fuzzy (new tubes generally have crisp flashing edges). It's a semi-scientific judgement at best. Plug them in and give them a try.

Dave

[ak-47]

Sorry - I was not talking about power-up flash. I was referring to the silvery flashing at the top of the tube. It's pretty transparent on those Motos. Some manufacturers exhibit less flashing than others, but those are thin and the edges are fuzzy (new tubes generally have crisp flashing edges). It's a semi-scientific judgement at best. Plug them in and give them a try.

Ok, thanks.. I did not know that. I will try to mess around later this week with the mullards and motorolas and let you know what I think.

The PC 86 is apparently an RFT... as these are a 9 pin triode, can they substitute for a 12ax7 or 12at7? ... I know so little about tubes

[mhuss]

The PC 86 is apparently an RFT... as these are a 9 pin triode, can they substitute for a 12ax7 or 12at7? ... I know so little about tubes

That is a UHF oscillator tube. Two problems (1) there is only one triode inside (unlike the 12A?7 which has two) and (2) The pin-put is completely different.
http://www.radiomuseum.org/tubes/tube_pc86.html

--mark

[ak-47]

Thanks for the heads up Mark... After reading around, I am quite sure that once I put one of the M8162's in I won't really be too interested in all that other stuff anyway