This JJ ECC803-S / 12AX7 vacuum tube offering has huge plates in its triode sections giving it a real punch with lots of gain. The larger plates combined with crimped construction may contribute to the background noise it produces. While not actually bad, it’s enough that in some high gain amps you may want to avoid using it in the #1 preamp position. This amplifier 12AX7 tube is really well built. The large dual triode assembly is impressive and well aligned within the bottle. I’ve had great success using it in the cathode follower circuit that many great amps use to drive their tone controls.
Review – JJ ECC803-S Tube