Preamps better than Parasound JC-2 ?

I have a Bryston BP6 in my system and it's the closest thing to "straight wire with gain" I've heard in my system, so I agree Bryston preamps may be a very good option given your experience with a passive pre. Crystal clear transparency with an expansive and very dimensional and layered soundstage with pinpoint imaging is how I'd describe it. There's a nice BP26 for sale here now that has balanced connections and is about $1000 less than a used JC2. You could always sell it for little/no loss if it's not to your liking. Best of luck.

For a tube preamp Audio Horizons TP2.3 with full mods is the biggest sleeper I know of in high end audio.

I disagree on the Audio Horizons. I heard this against a 30 year old Counterpoint SA-5 last year and the Counterpoint tore the AH to pieces in portraying space and harmonic overtones. It's very very rare that I hear a tube line stage or preamp sound as flat as the AH. In the $2-3K range, there are many many options and the AH would not be on my list.

JC-2 is now in house. Did a brief comparing this morning. I am somehow feeling that my TVC is more transparent than the JC-2. The JC-2 seemed "louder" and I cannot go past 9 O'clock position for my normal listening position. At that position, it is already loud.
Honestly, I am finding it a bit difficult to "like" the JC-2. I had very high hopes for sound improvements. What would you specifically look for when comparing pre-amps? I used the following CDs for comparison:

Eva Cassidy - Live At Blues Alley - Fields of Gold
Norah Jones - Come Away With Me
Big Joe Mahar - Got My Mojo Working
Cassandra Wilson - Lover Come Back to Me & The Very Thought of You

I will continue to listen and compare the pre-amps again tonight, before returning it to the shop tomorrow.

"Honestly, I am finding it a bit difficult to "like" the JC-2. I had very high hopes for sound improvements. What would you specifically look for when comparing pre-amps?"

That's why you need a really good line stage if you want better sound than your passive. One thing you need to do before making a final decision on the JC-2 is leave it on for a while. I've seen many times where SS gear benefits greatly from letting it warm up for a day or so. If you leave it on from now until tomorrow, it should sound better. I still don't think you'll keep it, but you never know. If you want to try a different active, I still recommend the Ayre K5. There's a good chance you may like it better than your passive.

"The JC-2 seemed "louder" and I cannot go past 9 O'clock position for my normal listening position."

That's normal. A passive preamp doesn't have an amp. An active one does.