Re: Here, we discuss tubes...
"Mixing tubes does damage to the amp"
What in the hell are you talking about? When you replace the power tubes you should replace them all at once with a matched quad or pair and bias them correctly (if your amp needs biasing). You will not damage your amplifier by not following this, but your performance will be suboptimal.
Preamp tubes you can mix and match as much as you want.
Groove Tubes is a rebrander, they dont actually manufacture anything. They buy shipping containers of tubes from Russia and China and "Stringently test" the tubes. Those who "meet their standards" get slapped with their logo and that is that. 50% markup please.
There are only 4 operational factories of vacuum tubes producing any kind of quantity.
- The Svetlana factory in Russia, which is owned by New Sensor/ElectroHarmonix. They also manufacture under different brands like Tung-Sol and Mullard that they bought the rights to. As far as I understand these are just labels; they did not purchase any tooling that went with the old reputable brands.
-Shuguang (sp?) in China. I think these are made on old Philips machines that the chinks bought for scrap in the 90s. These are shit.
- JJ Electronic in Slovakia. These are built on the original TESLA machines that were bought by a former employee when the original TESLA electronics cartel was broken up in the 90s.
-Some other factory in russia. Can't remember which brands they make
When it comes to NEW manufactured tubes, the only ones I bother with are JJ. The only real option is between JJ and the Svetlana variations, and I have no patience to keep track of how the Svetlanas are being marketed or branded. All JJ tubes in North America get sold through http://www.eurotubes.com
, and they will guarantee everything if bought from them. They are also the cheapest new production tubes because they don't have the stupid markups other brands like to tack on.
If you want to talk about New Old Stock or Vintage tubes, thats something else. Good bargains are Telefunken, especially since they are impossible to counterfiet. They have the diamond logo molded into the glass rather than just painted on.
EDIT: Looking at the TSL schematic, much of the distortion appears to be created by FETs (transistors) acting as clippers. Basically a distortion pedal circuit in your preamp. I don't think cork sniffing your tubes will make that much of a difference.