Neutral to Lean Power Cord for tube preamp


I recently added a deHavilland UltraVerve preamp to my system. It is quite powerful and dynamic, but has a little too much bass emphasis through my Von Schweikert speakers, driven by a McCormack DNA-1. All cables are silver, using a VooDoo power cord now on the preamp. Everything plugs into a PS Audio Quintet on a dedicated line. Looking for a very neutral, or slightly lean more detailed power cord, price range is up to $400 used. I am still tube rolling, so bass may get tamed a bit more yet.
tube540
Agree with Brf move the speakers away from the front and possibly the side walls to balance/reduce the Ultra Verde's bigger bass. If that doesn't "tighten up" the bass enough for your taste do what Dmailer suggested for the last bit of detail before going to room treatments.
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ESP Essence Reference does exactly that but in a good way. It tightens up the bass (chopping off fats ?) and also makes the bass very tuneful and rhythmic. In the process it does amazing PRAT with a very clean, articulate background/soundstage. I think you will love it. It has the same effects on every component of the chain.

I will not recommend this power cord for already neutral systems (all solid state) as it can make the sound bit too tight. Otherwise it is one fantastic PC.
You can also get a similar impact by putting your preamp under Symposium Rollerblocks. The rollerblocks are wonderful for tube equipments. The ESP will have a more profound impact though.
I own an ultraverve and would suggest the VH Audio Flavor 2 for a good synergistic power cord. I have tried lot of cords with the Ultraverve and keep coming back to the Flavor 2. Also be aware that lots of gold ended cords can cause too much warmth in the bass in your system. So be sure to check your other cables and if they are all gold try brass.

Also the other suggestions about resonance control should be investigated as well. Good luck.