Will VPI's Classic 3 sound much better with a SUT?

Most integrated amps have an active line stage which adds gain. At least the older ones do! I guess the single tube driver for the output stage of the Fosgate adds gain. Otherwise it wouldn't have enough voltage to drive a typical power amp.

.3 x 1000 = 300! 

".3 x 1000 = 300!"

Not when you're talking millivolts.

"0.3mV multiplied by 1000 = 0.3V"

@lewm is correct.

Luckily I enjoy my vinyl system as is...but I appreciate any ’tweaks’ / upgrades that work. Thank you for our group conversation / education on maybe adding a SUT.

FYI My Unison Research ’"Unico" integrated amp is the first version sold, with 2 tubes and a wireless remote. Volume Level 4 out of 10 is enough for me. I upgraded the tubes to Mazda’s PLUS had two levels of modifications done - they clearly improved the overall quality, detail and soundstage of the audio to me: https://6moons.com/audioreviews/unison2/unico.html.

Unico Mods:

• Three sheets of SoundCoat chassis damping material to the inner chassis
• 2 premium mil-spec, ultra low noise/microphony Mullard CV4003/12AU7 designed for 10,000-hour operation
• Two Multicap PPFXS polypropylene film and tin foil inter-stage coupling capacitors
• Two 1uf Auricap metallized polypropylene preamp input coupling capacitors
• Twenty Japanese Riken 0.5- and 1-watt signal path carbon resistors with gold-plated leads
• Two feet of DH Labs Revelation Series pure 99.999% silver solid-core input signal wire with Teflon tape-wrap dielectric
• One pair of premium Vampire direct gold-over-copper-plated RCA female jacks
• Four WBT 0763 single output binding posts
• TRT WonderSolder used throughout
• 8 Vishay-Telefunken SF4007 ultra-fast soft recovery diodes to rebuild two existing bridge rectifiers
• 6 Black Gate electrolytic capacitors to the power supply
• Two custom-made Burr-Brown OPA-627 opamp-based PCBs to dramatically upgrade the amp driver stage

:

Jason, do you really believe this?: "Most mc stages amplify a mc cartridge’s voltage TEN times for use with a typical phono stage!" Because most MC gain stages supply at least 60db of gain to the signal, and frequently much more than that, which counts for a lot because "db" is a logarithmic quantity. For example, 66db is equal to twice the gain seen with 60db or ~2000X increase in signal voltage. So the baseline 60db (which is what the Fosgate happens to supply) is equal to a 1000X gain in voltage. There are numerous on-line calculators you can consult, if you insist upon your particular belief system. It’s OK to be in error, but once the facts are given you, accept them. And as far as your pointing out that 0.3 X 1000 = 300, that is correct, but you left out the units:  0.3mV X 1000 = 300mV = 0.3V

Furthermore, like I said above, if MC gain stages could supply only a 10X increase in cartridge gain, the analog signal chain would not work; "3mV" that you propose to be the result of multiplying the cartridge output times 10 would not even drive an active linestage, let alone any amplifier. And I gave you the reasons why I think the Unison has only a volume control for a linestage ahead of the amplifier section.

Vinylfun, The version of the Unison Unico that I looked up (in the context of a Stereophile review) has only one tube, a 12AX7, instead of two 12AU7s. In either case, the tube input stage drives a MOSFET output stage, so far as I can tell. In your amplifier, one of the two 12AU7s may be used as a cathode follower, which adds no gain. In the review, there was no mention of an op amp. I imagine it is used for phono, if the Unico has the optional phono section, but I certainly could be wrong.