Rogue Audio and Audio Research Comparisons

Thank you Gakerty. I did buy some CBS 12AU7 but not the medical grade you mentioned.  They are a bit pricey.  The CBS tubes just have a nice linear sound but haven't spent that much time with them yet.  Amperex 12ax7 so far are my favorites.  

I ran my ST-100 with Gold Lion tubes. Stock JJs don’t cut it as they sound plain and flat. I also had good experience with Brimar CV4003 from Upscale combined with the Gold Lions it was the right blend. The amp also sounded much better in Triode mode than it did in Ultralinear. It produced sweeter more vibrant and dimensional soundstage. Rogue customer service is also first rate. 
The ST-100 is a great value in its own right but it isn’t Audio Research Ref75SE level. The degree of improvement will depend on the components chain and speakers. I don’t think it’s possible to quantify without taking all this into consideration. 

I’ve had a full stack of current Rogue tube gear (phono + pre + power), have a full current VAC stack, and have the ARC Reference phono + pre. And I’ve mixed & matched these components a lot.

The Rogue tube power amps are excellent (the best components they make), and can absolutely hang with and benefit from more expensive upstream components by ARC or VAC. As far as my Rogue Apollo Darks versus twice as expensive VAC 200iQ monos, the Rogue is a bit dry and SS-like in midrange (VAC more lush and romantic here) but also has decidedly superior bass response. Seriously, the bass is amazing. It absolutely hangs, overall. The Apollo Darks (tons of power and dynamics) with VAC Master preamp (this injects some sweetness and just sounds amazing all-around) and Ref 3SE phono (best phono stage I’ve heard) is a really nice combination. Haven’t heard the ARC power amps in my system yet, though.

As far as the full Rogue stack phono + pre + power - no, that wasn’t my jam. I definitely prefer ARC and/or VAC upstream components. But then I’ve been told the new Ares II makes some good strides forward, and I haven’t heard that yet.

@mulveling looks like someone has some fantastic experience with various manufacturers components.  That's what makes this hobby fun.  I'm glad you think Rogue amps are quite good.  Definitely enjoying mine and from my experience and Rogue offers a LOT of value. I agree the midrange can be a little dry at times however,  rolling in NOS tubes helps. I inserted a pair of Mullards in the 2nd slots in my Primaluna Evo 400 preamp behind the Brimars in the front slots and that helped richen things up.  

@samzx12 

Sell your gear and get all Primaluna :)