Sovtek 12AX7LP and 12AX7LPS

[OnTheCorner]

What is the difference between a Sovtek 12AX7LP and a 12AX7LPS? And I am planning to put at least either the 12AX7LP or the LPS back in the preamp nearest the imput with 2 EH12AX7s. Is the SovteKc 12AX7LPS an upgrade of the Sovtek 12AXYLP?

[myles_rose]

Originally posted by OnTheCorner:

What is the difference between a Sovtek 12AX7LP and a 12AX7LPS? And I am planning to put at least either the 12AX7LP or the LPS back in the preamp nearest the imput with 2 EH12AX7s. Is the SovteKc 12AX7LPS an upgrade of the Sovtek 12AXYLP?

The LPS has a spiral heater element that was developed to reduce AC hum in amps that used AC for the heater filiment. These amps are amps like Fender amps for the most part. The LP is better used on DC heated amps, such as Rivera amps.

 

Regards,

[OnTheCorner]

Thanks for the response Myles. We know you're busy. Can you tell me if the Peavey Prowler (2x6L6 driven by 3 12AX7s) is a AC or DC amp. If not, I'll understand and contact Peavey. Not very many people are familiar with that amp. And it was discontinued, possibly because it was competing with the Classic series and the Ultra series which had 4 preamp tubes. But I got it for $299 + tax brand, spankin new! It didn't even look like it was tried out much. The Peavey came stock with 2 Sovtek 12AX7LPs and 1 Sovtek 12AX7LPSs. I assume V1 is the preamp tube nearest the imput and V2 is next to it and V3 is next to the power tubes. As it stands right now, I swapped the Sovteks out for Electro Harmonix 12AX7s and it seems to be quieter. Was considering pulling the VI/EH and putting in the Sovtek 12AX7LPS. But your excellent report on the inconsistencies of preamp tube manufactoring is disgusting.

 

RMH