The Sovtek 12AX7LPS is a Large Plate 12AX7 valve. The spiral filament reduces hum in AC filament amps - while the larger plates allow for a more linear response. This is one of the finest modern production 12AX7's being made by Sovtek today.
I do not recommend them for use in the gain stages of high gain amps if you like to run your gain full on. All preamp tubes are microphonic it's just a matter of where the threshold is and longer plate tubes will squeal before a short plate tube will, so for real high gain amps I would stick with a short plate ECC83 (12AX7). I wouldn't recommend these in small combos where the tubes are in close proximity to the speaker.
These are premium and tested on specialised digital and analogue testing equipment by Karltone as follows
- Gain (A)
- Transconductance (gm)
- Noise (dbv)
- Emission Quality
- Grid Leakage
Test results are provided with purchase