Tube preamp recommendations $3K-$7K range

Hi Daniel,
I think you have a really nice set up. If you are happy with it Don't change it. But if you must... from what I have read I think you have gotten some really solid advice. So you have time on your side to research.  I am adding a few options to explore. 

Rogue is very powerful, Dynamic friendly to tube rolling.
http://www.rogueaudio.com/Products_RP7.htm

Stage 3 Concepts is a fantastic cable company. They build great power cords. Add this on to any preamp/ amp, its like adding another component.
https://www.audiogon.com/listings/ac-cables-extreme-audio-power-cables-15-a-us-plug-1-5m-length-2017...

Add this to your existing preamp and it will most likely give you what your looking for.
https://www.audiogon.com/listings/ac-cables-1-5m-mint-2017-12-15-power
Enjoy the search, Good Luck

https://www.audiogon.com/listings/tube-teflon-caps-and-extra-tube-set-2017-11-18-preamplifiers

This looks like a pretty sweet deal at the bottom of your price range. No affiliation with the seller. Good luck!

I had an idea to design a little remote controlled motorized thing that had a wheel with a rubber belt that would go around any volume knob and presto!…all preamps now could be turned up and down remotely. I was going to call it the "Knobulator." Now I don’t care, but maybe I should revisit that…remote mute is also important as my wife always says stuff to me while I’m listening to music and I have to mute or I could miss something important…like "the car is on fire" or "I’m leaving you for Clem." Also, I like Teflon caps as eggs don't stick to them.

Lots of great input, thanks. Lots of familiar names and some unfamiliar products for me research.

@hifiman5 and  @1marker: Joe at The Cable Company gives a strong recommendation to Backert Labs as well. Mentioned that he relied on Bob Backert for his CJ maintenance for many years.  He also suggested Rogers Hi Fidelity. I'd never heard of them. Their reviews are outstanding but they only make integrateds.

@ggc and @hifiman5 : As I am generally satisfied with my system, I'm thinking now along the lines of "tweaking" or "enhancing" my current sound with further mods, rather than swapping out my pre. It's a lesser cost option and I must say I trust John Hillig's ear and his work to date.

Along those lines, Musical Concepts offers two additional upgrades to my already tricked-out Hafler DH 110 pre.  One upgrade is their MC-3  circuit board mod.  This is what their website says about it:

From Musical Concepts re the circuit board mod:
...Phono, line stage and four individual power supplies are on board. Preamps with the MC-3 board are often accused of sounding tube-like, vividly three dimensional and very dynamic while retaining a solid bass authority.

• Phono stage with excellent RIAA response
• Adjustable DC offset in phono eliminates need for output capacitor
• DC-Coupled line stage with very wideband performance
• Totally discrete transistor circuitry, no ICs
• Totally dual-mono construction on one board
• Dual-Mono regulated power supply
• Dual-Mono power rail distribution
• Power and signal ground systems independent by channel...

The circuit board upgrade requires the OPS-8 external dual mono PSU as well.

Musical Concepts on the dual mono external PSU:

...Expect excellent dynamics, low noise, tonal purity, maintenance of distinct instrumental clarity at even high volumes...

http://www.musicaldesign.com/MC_Haf_premod.html

@hifiman5 : A less costly approach (new circuit board is $800), would be to just add the external PSU to the pre. I agree that the Modwright modded Oppo Sonica with Dan's tube rectified external PSU is magical improvement on the stock Oppo.  That said, I've read conflicting reports on the benefits of adding and external PSU to preamps.  Any thoughts? 

I'm not a tech guy, so specs are not terribly meaningful to me.  However, I trust what MC has done with my Haflers to date, and may invest in this "final tweak" to my solid state preamp. Downside of course is that any return on mods is lost in the used market. 

Thanks all.

Rogue RP-5.