How do I warm up my system?

Back in the day I owned equalizers by both MXR and Luxman. I remembered they made a difference but didn't as much as one bought better equipment. Zar

Have a few beers. That usually takes the edge off! Seriously, I had tube amps that sounded bright with two different speaker manufactures and it was my speaker cables. Actually, I think it really is a mismatch between your amp and speakers but you can fix this with cables. Start swapping.

I think this mismatch is due to a tough load from the speakers. I admit I have no experience with SP, but you should take a look at the impedence curve from any reviews if they exist. Average impedence is irrelevant; if the curve dips low, say 3 ohms at any frequency point (usually on the lower frequency side), tubes seem to sound hard/bright. I don't know why this is so, but matching tube amps to speakers is tough regardless of what the manufactuers say.

I have VTL 300 Deluxes tube amps which are supposed to me tough monsters but they are finicky with speakers. Real finicky and the first thing to go is not the bass as most would say, but a hard/bright sound. You think you have this hobby figured out and then......

Turn it on & let it play. I hate trick questions.

"it's interesting. nobody has endorsed an equalizer. why ?"
-Mrtennis

In my case an equalizer constricted the soundstage, even when in the bypass mode. I had it modified such that the bypass mode now emulates a hard wire connection, and the soundstage degradation is no longer audible for me--IF the equalizer is in the bypass mode. I'm told (by Duane, a dealer friend of mine) that the only equalizer that didn't degrade the sound was the Cello by Levinson, but it was priced at 14,000 dollars.

your electronics may be spectrally unbalanced and unforgiving of poorly recorded source material.

i ahd the dehavilland in my system and sent it back. i did not perceive a tube like sound.

the nuforce is solid state and also not very kind in the treble range.

you could try anti resonant devices under components designed to "soften", such as furniture foam, sorbothane, sound fusion sound boosters.

you could try changing ac c9ords for your amp and pre. you could try line conditioners and other filter devices.

but, unfortunately, short of changing your electronics (i'm not familiar with your speaker), only an equalizer will create the results you desire. try 'em you may like one of them.