The Electro Harmonix 12DW7 triode is two triodes but one has a gain of 100 and the other half a gain of 20.
Think of it as having one half of an ECC83 ( 12AX7) and and the other half from the ECC82 ( 12AU7). The Electro Harmonix 12DW7 triode valve is certainly an interesting vale for experimenting with your sound especially if you want a clean sounding amp.
It can be used to lower the gain in amps. Some interesting sound modifications can be made with this valve .
Peavey and Ampeg amps take advantage of this feature. It is also known as the ECC832. This one is made in Russia. As the valves is designed with two different gain stages it cannot be matched / balanced.
We test every valve we sell.
We have these in stock in Yorkshire, Uk and the price includes 2nd class post free