What is Tight Bass?

By the way OP, you mention electrostatic.

Sorry, you won't get any bass below 50Hz from an electrostatic, even though they're great at all points above. 

Many start to roll off at 80-90Hz.

A dichotomy on amplifiers for good bass?  'Tight' if you like, but I prefer accurate, or true to the live event.

Some suggest only tube amps supply bass that reproduces the live event well.

Others that only solid state amps have the raw power required.

May I suggest the reconciliation is in the power supplies.  All accurate bass reproduction needs very stiff power supplies that allow the amp to control big woofers rigidly.  The best amps of every type have big power supplies.  When I switch on my big Krells the houselights dim as the huge capacitors suck juice from the wall.  Big ARs have massive transformers.

@mijostyn 

I am convinced you are utterly correct about the superior SQ of pure Class A.  I will never leave it.

My Krells are KRS 200s, the last reference before Krell were shamed into abandoning Class A because of the power consumption.  Mine draw more than 1kW per side continuous.  They are one of the very rare early pairs that were converted to deliver 400w/side and mainly suppied to Krell agents (where I got mine).  They are getting on for 40 years old now and I had them entirely refurbished (mainly caps) in 2011.  I also have a KSA 50 in another system - Krell's first product and glorious it is too.  That one continues to emit signal (albeit increasingly distorted) for nearly 10 seconds after it is powered down.  That's what I call a power supply.

IMHO you could do a lot worse than go back to Krell monoblocks.  I see a pair like mine, recapped, for $12,500 today.  In view of Class B amps in $six figures, this must be the bargain of the last two centuries.  I paid £6,500 in 1992.  List in the mid-80s was about £26,000 I seem to recall.  They are often cheaper than £12,500 but I paid £3,600 to refurb mine.