Herron VTPH-2A vs Rogers PA-2 Phono Preamplifier

I know nothing about the Rogers unit, so can't help you there. 

Frankly, the VTPH-2A sounds so good with the stock tubes I've never given any thought to opening the case to even bother to see what tubes are in it.

And this is from a guy who has hundreds and hundreds of dollars of tubes that I've tried in my last preamp. 

By the way, I have also not looked inside the Herron VTSP-360 ESP that I replaced that tube preamp with either.  It's also that good.

Also because if you’re using an LOMC cartridge, you’re basically listening to an FET. If I understand the Herron phono correctly.

lewm

... if you’re using an LOMC cartridge, you’re basically listening to an FET. If I understand the Herron phono correctly.

Not really. It's not unusual for a tube phono section to use an FET at the MC input. ARC does this in its Ref Phono preamps and they sure don't sound like listening to an FET.

Please describe what listening to an FET in the context of a tube circuit sounds like. ARC preamplifiers are certainly not known for warmth. FET/tube phono stages can be among the most neutral. I certainly don’t mention it as a criticism of the Herron. My Manley Steelhead is also a hybrid as are many other phono stages we like to think of as “tube” types. Typically you have at the input a cascode consisting of a FET on the bottom and a tube on top. That gives tremendous gain and very wide bandwidth. It also eliminates or drastically reduces input capacitance. My point was that in this topology much of the gain comes from the FET. Therefore shuffling tubes downstream would have less noticeable effect on SQ, compared to an all tube circuit. Alternatively the FET drives the grid of what would be the first gain tube in a conventional tube RIAA. The FET acts like an outboard head amp .

The Herron has two two gain sections - the FET front-end used only by the MC circuits, and tubed gain stages used by both the MC and MM sections.  You are not just listening to a FET through the MC stage but in my experience MC carts sound best using a quality SUT through the MM stage on the Herron.