Would There be a Significant Difference

So, my question is, if I spend the money for one of these preamps, ranging from about $2500 to $5500, will I notice a significant improvement in the sound quality? Secondarily, would folks recommend I stay with a tube model

Yes and yes. Preamps are a crucial component in terms of overall system performance, so upgrading it will yield significant improvements. Since you’re already used to having a tubed pre I don’t think you’d be happy switching to solid state — especially hitched to your Benchmark amp the sound may skew too far to the clinical so I’d stick with tubes. Of the ones on your list and if you want to run balanced the Rogue is the only tubed pre that I know is fully balanced from input to output (not sure about the PS Audio) and would obviously be a considerable step up from your RP-1. The other advantage is you already seem to like the sound of the Rogue so you can be pretty confident you’ll like the RP-7 as it just provides a lot more of the good stuff you like about the RP-1. 

Assuming you’d like to stick with a more neutral sounding tubed pre like the Rogue and not go with a warmer sounding unit, I’d also recommend looking at a used Audio Research Ref5SE, used Atmasphere MP3.3 or new MP3 that you could upgrade later. All this said, the most important thing is that whatever pre you choose has the sound characteristics that match best with your tastes and system, so I’d suggest going to listen to all you can or, if that’s not possible, read as many reviews as you can to try and get a feel for their sound characteristics. Hope this helps, and best of luck in your quest.

(ps You can pick up a used iPowerX power supply for your Zen Stream for only $75 at B&H if they still have some left an I’d recommend at least getting that or maybe even a linear power supply — it can make a big difference in sound)

Hi Mike -

What is it that you are looking to improve or is deficient?    

You have nice equipment as it is.  I would not zero in on the preamp as a potential limiting factor.

Rich 

+1 for a great sounding tubed preamp. Makes a huge difference on the whole system. I recommend a used Audio Research, Conrad Johnson, or VAC. Spend the maximum you can and extend with it being used. The companies I refer to build true audiophile preamps worth keeping for a lifetime… or a decade or two depending on your age. 
 

I have owned Audio Research preamps and phono-stages for decades now. Once they went into my system… I was done looking… I would only upgrade when I could afford it. They are natural sounding, detailed, with great midrange bloom and outstanding sound staging. 

I’ve used Tannoys almost all my grown-up audiophile life. You should be set with the Fynes! They look like great speakers. I agree you should explore upstream upgrades, as your Fynes can certainly reap the benefits.

I’ve used Rogue gear for many years. Honestly not a big fan of their RP preamp series. Haven’t heard the RP-1, but a guy I trust has said repeatedly that’s a weak spot in the line; there’s a big performance jump with RP-5. So you could jump to that or RP-7 and do quite well. But I’m also pretty confident a used Rogue Athena or Hera would spank any RP preamp. Those were their flagship preamps before RP series. I really preferred that older preamp line.

The ARC Reference 6 is quite phenomenal and would blow your mind. It’s out of your price range, but the 5SE may brush against your upper limit, and is worth a look too.