tube rolling suggestions - Page 2

It really depends on the tube socket, wiring and such. For example with octal tubes, you can use the 6/12sn7, 6BL7,6BX7, 6sl7, etc... Then you have 9 pin mini tubes like the 6CG7s, the 5687s and the 6350/6463s. And you have loctal tubes like the 7/14n7, and the 14/7af7. That said in terms of the tube adapters with the 9 pin mini tubes (I'd imagine this carries over to the tube sockets), given the different wriing/pin configuration, the adapters for the 5687s and the 6350/6463 are different despite their being both 9 pin mini type tubes, and if you wanted to use both kinds in your amp you'd need both type of adapters. In terms of the 5687s, you'd also need it biased at 6 or 12V as the adapters/socekts are fixed.

That said IMO the key concern is that your transformer can handle the amount of power that some of the tubes are producing. In the case of more powerful tubes like the 6BX7GT and the 6BL7GT, you'd need atleast a MPX3 transformer in your amp.

Another key concern of note is that if you are using 12V tubes (12sn7, 14n7, 14af7, etc..) you will aso need to get the 12V option as it needs that additional power supply for your tubes.

If you have an MPX3, you can use the 6BL7, 6BX7, 5687s, 6350s, etc.. just fine, but if you want to use the 12V versions of some tubes you'll need that 12V option on your amp.

IIRC, here some basic exampels of the tube types/sockets that you can use. Some require adapters:

Octal: 12/6sn7, 12/6sl7, 6BL7GT, 6BX7GT...
Loctal: 14/7n7, 14/7af7
9 pin mini:

5687
6350, 6463
6CG7

The 3 9-pin mini types require their own unique adapter. a 5687 adapter won't do it for a 6cg7, etc...

Note: the loctal tubes and each type of 9 pin mini requires a tube adapter unless you get him to make the default sockets 9 pin mini (for whichever tube type you wanted to use) or loctal.

6sl7 in MPX3 Slam?

Has anyone used a 6sl7 in their MPX3 Slam? Combined with what other tubes?
How did it sound? I picked up a 6SL7WGT Sylvania chrome short brown base, a JAN CHS 6SL7WGT short brown base with plates about 1/2 high with D getter, black base Sylvania vt229. Any experience with these tubes?

The 6sl7gt has way to much gain for the Singlepowers. The typical 6sn7 has an amplification factor/ gain of 19-21. The 6sl7gt's have an amplification factor/ gain of 70. I have discussed this tube with Mikhail and he has consistently discouraged me from using them.

"In the case of more powerful tubes like the 6BX7GT and the 6BL7GT, you'd need atleast a MPX3 transformer in your amp."

So in the case of a PPX3 SLAM (with the 6SN7 option), the 6BX7GT and 6BL7GT tubes would be un-exceptable in the input socket due to the limitations of the PPX3's tranformer?

Please clarify.

- augustwest

Yes if you wanted to use a the 6BX7GT or the 6BL7GTs in a PPX3 (SLAM or not...) you'd need atleast a MPX3 transformer to use them due to limitations in the PPX3 transformer.

Yesterday, I plug two 6BX7GT with my supra.

They are good and lower cost.

When I rolling tubes, I will do after 15 mins when switch the amp off.

I don't know is it right?

Never heared an exact time on when a safe time to tube swap is.I give it a minute every single time is do it since before i would hear a static kind of sound if i tried to do it right after turning the amp off.Better safe than sorry i say.

"Sylvania "Bad-Boy"

Which Sylvania tube in particular is this one that you are referring to? Sylvania seems to make so many different 6SN7 varieties.

- augustwest

This all can get pretty expensive when you add in the costs of the tubes and maybe some adapters too. In the end, I know I'll probably have just a few favorites, or maybe not. So with me, it's the journey that's so much fun. Every once in a while, I'll find a sound treatment that makes me cry. I did the other day and that makes it all worthwhile.

Earl, has very patiently taught, me just about everything that has been discussed here and for that I am very grateful. What I'm learning now is how "tube tweak" the sound based on the music playing and the mood I'm in. Headphones are the K701s.

Also, Mikhail has personally tweaked my MPX3 to fine tune it to my system and desires.

It all comes together. Isn't this fun?