seeking recommendations for a preamp


I've been lurking a while, but this is my first post. I will appreciate any advice given, and thank you for reading this.

My Kenwood C2 bit the dust. I have lost the right channel, and the input selector is also going out. I'm looking to replace it, and upgrade quite a bit. The wife has given me a $2500 budget, new or used is ok. I listen to Vinyl a lot, as well as my echo dot which is also plugged into my preamp with a headphone to RCA adapter. I'll list my other equipment now.

Completely rebuilt Altec A7-500 with all new parts from GPA
JBL L200s
Kenwood M1D amplifier
Homebrew rebuilt Monoblocks from Zenith consoles with EL84/6BQ5
Yamaha EQ
Thorens TD 318 with an Ortofon cart. Unsure which one as I am at work
SVS PB16 ultra

The room is 16 wide by 20 deep. I primarily listen to the Altecs and tube amps with the SVS sub taking up the slack in the bass from the A7s. Sometimes I listen to the JBLs driven by the Kenwood M1D. I notice that the echo dot sounds a lot better than my turntable, so I know I must be needing a better phono stage. I've tried swapping out turntables with a couple of Dual 1229s with Shure M97XE carts that Bill at fixmydual has gone through thoroughly so It's not isolated to my Thorens. I guess I' surprised that the $30 Echo Dot sounds so much better.  

I admit I don't have the best cables, and will upgrade those as I can. I feel like the preamp is the heart of the system so I want to make a good choice. I love Macintosh, based purely off emotion, but don't know if it's the best choice for my situation. I do not have a local shop to audition, and none of my friends are into audio. What preamps should I be looking at ??
128x128adrianleewelch
As atmasphere said, get a 6sn7 line preamp. I had a 12au7 based line preamp for several years. The 6sn7 sounded much better. I would also get a separate phono pre as it will give you more flexibility on price, features, and upgradeability, etc. For example if you don’t need MC capability, don’t pay for it. Have a general, longer range plan for your budget also. Don’t try to solve everything at once. Evolve and upgrade over time. That is the fun part of the hobby!!
AVA, Parasound, or Bel Canto 2.1. Several fine tube preamps at your price point as well. 
Whatever you consider, audition it if possible.  Pre-amps are in my opinion a very weak link in the audio chain.  Specifications in most cases are worthless.  
Happy hunting!
Room correction is something I’ve always been curious about though. I feel like I should have tighter bass with the SVS. It can be a little loose and muddy at times.
Rather than room correction (which can’t fix a standing wave in the room) consider something called a Distributed Bass Array. The idea is simple- by having multiple subs operating **below** 80Hz you can break up any standing waves in the room and thus get good bass.


If a standing wave is killing bass at the listening position(s) all room correction will do is try to put more power into that frequency. But a standing wave causes cancellation (IOW is a null point) so any amount of power you put into that frequency won’t change things.

The best DBA I know of (and one of the best subs around as a result) is the Swarm made by Audiokinesis.
I don't see that anyone has mentioned Modwright yet.  I have a LS 100 in my main system and love it.  It's 6SN7 based.  If you keep an eye out you should be able to find a used one under your budget.