All our preamp tubes are stringently tested for noise and microphonics using Amplitrex testers driving an external amp. There is no extra charge for low noise and microphonics testing like with other tube vendors. Additionally the tubes undergo a battery of tests for basic performance characteristics and faults such as: Emissions, Transconductance, H-K and Grid leakage, etc... If a tube does not pass our strict performance criteria it's tossed or sent back to JJ Electronic for evaluation.
We recommend these for long tail phase inverter stages or anywhere that symmetrical plate current between triodes is sought. It also gives you the plate current and transconductance sped for each triode which is nice if you're trying to keep records or to maintain exact consistency from tube to tube. If you need multiple matched tubes please see our "Balanced and Matched" option.
The JJ ECC83S utilizes a historically recognizable short plate design and spiral filament. This contributes to the tubes inherently low noise flow and resistance to mechanical noise and microphonics. This makes them ideal for combo applications and high gain stages.
Tonally these tubes have a very even voice with a dense harmonic structure when overdriven. Compared to other 12AX7 types this gives them a warmer and thicker tone. This also makes them very versatile and a great overall platform. If you're looking for a neutral voicing with tight dynamics this is where you should be.
