I think replacing your Alesis monitors with something a bit more high end is a better solution than adding a tube pre. YMMV.
The thought's crossed my mind. I still have a pair of VR-1s hanging out in the basement needing a home. They definitely sound better to my ears than the monitors. And I'd forgotten about the VR-1s until just now. I'll replace the monitors with the VR-1s if I go with a tube pre/amp.
http://www.soundstage.com/revequip/vonschweikert_vr1.htm
"The VR-1 speaker disperses its sound best without grilles, so preferably you’ll use it that way for serious listening. But if you need to use the snap-on grilles, they have been acoustically treated with foam around the tweeter area to help soak up some of the high frequencies, so they don’t get bounced around by the grille’s edges.
The VR-1’s impedance is said to be a nominal 8 ohms with a 4-ohm minimum point in the bass. The sensitivity with 1W input is 90dB "in-room." Bass is quoted, again, in real-room conditions, where it’s said to extend to about 40Hz. VSA offers different power requirements depending on your use of tubes or solid state. For solid-state amps, they say 50 to 100 watts; for tube amps they say to use 10 to 100 watts."
I'd say 20wpc in tube minimum...
Lower power = higher distortion, for good or ill.
Bob,
Can this also be assumed about my Soliloquys?
I have the 6.3's, which are floor standers, and 90dB efficient. They're said to be tube friendly, and have wattage needs of 10w -> 400w
I'm presently driving them with the Plinius 175w SS amp, which makes them sing at the first perceptible watt. They sound gorgeous at that point.
What I've been theorizing about, is purchasing a DIY tube kit; either the Dynaco st-70 kit, or, the Dynaco st-120 kit, both from Bob Latino.
They are both based on all new parts, and a stainless chassis (the originals were chromed steel).
I'm totally comfortable in my soldering skills, and am not slightly intimidated in building my own amp (actually excited about it).
Given this, would I be better having more wattage from tubes, such as the 120w/60w-side?
The cost diff between the st-70 kit and the st-120 kit is not that far apart, with the bulk$ of the purchase being the expense of the stainless chassis.
My gut tells me more is better, but I do not know tubes, so I thank you, or anyone for the mentoring.