Will a phono pre-amp make a substantial difference

I am not familiar with the Rega Phono Preamp--although I have their Brio integrated amplifier, which is excellent--but I know that upgrading from the bottom Schiit phono preamp to a Lounge Audio Gold Phono preamp made a huge sound quality improvement when playing records back on my system, which consists of a THorens TD 126 MKII, Audio Technical 540ML cartridge (MM), the Loung Audio phono preamp, Rogue Audio RP-7 preamp, Odyssey mono bloc amplifiers, and Fyne F-702 speaker and two Rythmik 12Se Subs.  Some of my late 1970s and 1980, and 1990s audiophile LPs make it sound as if the performers are right in my room.  So, a quality phono stage can make a huge difference in sound quality.

Having a phono stage with on the fly adjustable gain is a huge plus. And one with a separate power supply is even better. 

pondac +1

By far the most significant upgrade I made to my vinyl source was moving my Linn LP-12 to a separate wall shelf.  Rega makes a wall shelf dedicated to their turntables. Take the hint 😆

@pindac 

+1 Although off topic. I agree. Turntable support and isolation can significantly improve the performance of a turntable. Well, while not to the same extent, isolation to a phono stage can improve the sonics. I have used Black Diamond Racing shelves and cones and better yet Silent Running Isolation platform. Lower cost solutions are out there. But this would be after a phono stage upgrade. 

ANYTHING PHONO: think ’preferred’, not better.

Thus, look for choices/changes/options that allow returns.

IF you can try/return the Rega Fono, why not, you will learn more about your NAD 33’s MM Phono by any comparison. 

However, I suggest you think long, and think about eventual use of a Moving Coil Cartridge, consider new boron cantilevers, perhaps eventually risk vintage cartridges to try sapphire or my recent favorite beryllium cantilevers.

either

a SUT to keep using your existing MM stage in your NAD 33 (or any future MM Phono Stage)

a Phono Stage with MC and MM capability.

Next, you need some optional settings for cartridge variations: different gain settings, and different impedance settings, even better if those are independant.

Also, consider removable headshells or eventually two tonearms, in which case you need to solve switching from one arm to the other.

I didn’t plan on going this far, but with help here, and lots of luck (after a lot of research) I ended up with a great plinth, quartz locked direct drive, 2, then 3 tonearms, now all with removable headshells, a small collection of MM and MC cartridges (new and vintage) and a SUT with 3 front selectable inputs, a few optional settings for MC, and PASS for MM (or High Output MC)

The more Jazz you listen to, so many greats made recordings prior to 1958 when Stereo LP’s began, and Mono LP’s definitely benefit (a bit, some, a whole lot) from True Mono Cartridges. 

I don’t NEED it, but my ability to play and instantly switch/compare stereo/mono/my or my friend’s cartridges: I got there bit by bit and I’m loving it.