Speedboost or other lps for Hagerman Trumpet MC

I realize this, I am probably not using the right terminology here.  The jfet front end in the Hagerman Trumpet MC uses a (I believe) 555 chip ad an oscillator.  So if there is this kind of "switching" device in the Trumpet, what good is an external LPS? 

Because you’re replacing the switch mode power supply wall wart with a toroidal power supply that has been shown to enhance the quality of sound. Don’t know what’s going on on the inside of your box. At this point, I would call upscale audio and ask them to give you a more detailed explanation.

The Trumpet MC’s internal circuit with 555 chip is tasked with multiplying 15V DC into like 200V DC needed for the tubes. The idea is not to mess with that. The wall wart contains a cheap SMPS which converts 120V AC directly from the wall into that 15V DC. THIS is what an external LPS is going to replace. 

If you don’t like the idea of that 555 based voltage multiplier circuit, then you’d need to look for some older Trumpet versions, most of which were MM-only. Those had their own beefy linear PSU’s with four chokes.

I never did try an LPS. The noise floor you hear is pretty much dominated by hisss / shhhh from the JFETs - and it’s going to be there no matter how clean the PSU is. 

I finally found one of the VERY few Trumpet References Jim made, and it’s a thing of beauty. Great implementation of the Trumpet and Piccolo circuits; no compromises. The Trumpet MC is still really sweet for its price point. 

@mulvelimg, that is what I was getting at with my question.  With the jets and the 555 chip.  I couldn’t see how an external LPs could get around the internals in the unit.  The external LPS would end up in a switching circuit to get the rail voltage required.  
On another note, what have you found works best in the v2 position?  12ax7 tube.  I want to confirm what this position is for.  Looks like it handles phase correction.  But I am not very good a reading schematics.  Any suggestions?

Sorry, spell check, jfets not jets.