how much current is enough?

Well, your Levinson is solidstate and those I mentioned are vacuumtubed. GENERALLY, when SS amps are 'monod', the channels are bridged so that the maximum power quadruples, not doubles. However, each channel drives only half the single impedance, so bridged SS amps are NOT high-current amps. The channels of tubed amps are paralled so they're generally able to increase current output enough to combine the output of the 2 channels. BTW, I understand that SS amp channels can be combined this way, but the only manufacturer I know of to recommend it is B&K.

For Mbacinello's VERY insensitive and low-impedance speakers, I am NOT recommending a bridged SS amp.
.

Numbers dont really tell the whole story about any given speaker/amp combination. That said, your speakers are notoriously power(current)hungry, and most amps dont produce a lot more current when bridged. You really have to try an amp with your speakers to see how they play together, sometimes the amp with more modest specs outshines the one with numbers that suggest it would be the better amp for the load. I can think of worse problems than having to find the right amp for the fine speakers you own. Good luck.

another simmilar question...so if the mani-2's (which i dont as yet own...but am considering) are 81 db sensitive...that means that
they will play 81 db with 1 watt, 84 with 2, 87 with 4 etc... that means that to get to the 110db...which there spec sheet says is there maximum volume level they would need 1024 watts of power...two things...is the sensitivity measured at 8ohms? such that a four ohm nominal speaker draws twice as much power from the amp?, in which case those numbers should all be double and it would draw 2048 watts at 4 ohms to play 110 db?? and secondly....thats way more watts than the speakers can handle, does that mean that they could never actually play as loud as there specs suggest??

thanks for indulging this speculation...not that i'd ever listen at these levels id just like to get a handle on the math governing the speaker amp connection...

i would not assume that the SPL output level is log linear with input power. the mechanical dampening in speaker systems probably isn't graphed in a straight line.

note from your exercise that if SPL is important, more efficient speakers are far cheaper than kilowatt amps. large speakers with many drivers tend to be the most efficent.

"Another simmilar question...so if the mani-2's (which I dont as yet own...but am considering) are 81 db sensitive...that means that they will play 81 db with 1 watt, 84 with 2, 87 with 4 etc. That means that to get to the 110db, which their spec sheet says is their maximum volume level they would need 1024 watts of power."

Yes, your process is correct but I didn't check your arithmetic.

"..two things...is the sensitivity measured at 8ohms?"

No. 'Sensitivity', a term that became popular with solidstate amps, is the acoustic output measured 1 meter away from the speaker when driven with a signal that produces 2.83 volts into an 8-ohm test load (which happens to be 1 watt) and driven by a constant-current amp, which means solidstate, not tubed. 'Efficiency' is measured with 1 watt of input INTO THE APPROPRIATE LOAD, and that term is NOT used much anymore. So...sensitivity is measured with 2.83 volts into 8 ohms while efficiency is measured with 1 watt (into the load equal to the speaker's rated impedance). See below about Totem's rating.

"...such that a four ohm nominal speaker draws twice as much power from the amp?"

Yes, generally.

"...in which case those numbers should all be double and it would draw 2048 watts at 4 ohms to play 110 db?? and secondly, that's way more watts than the speakers can handle. Does that mean that they could never actually play as loud as there specs suggest??"

Well, sort of. As merge03 indicated, these things never work out exactly because, at least partially, they're based on subjective measuring techniques.

Merge03 also is absolutely correct in his statement that high listening levels are FAR easier and less expensive to achieve with more-sensitive speakers than with very-high-power amps. Also, it seems that achieving a sense or feeling of dynamic 'ease' is much-more difficult with low-sensitivity speakers and high-power amps than with higher-sensitivity speakers and less amplifier power.

BTW, the Totem Mani-2's sensitivity is eighty-FIVE, not 81dB, at least according to their website. That will reduce your power requirement to 300 - 400 watts for 110dB. And it appears to me they specify it inconsistently--"Sensitivity 85 dB/W/m.". If they're claiming to indicate efficiency, that indeed is stated in output at 1 meter with 1 watt of input. If they're claiming to indicate sensitivity, that's measured with an input of 2.83 volts into 8 ohms. There's a real difference.

Also, and this is STRICTLY personal, and I know NOTHING about Totem speakers, so PLEASE don't anyone overreact to my comment here: any audio-equipment manufacturer that says "Regardless of specifications, “Mani-2” channelizes primal energy and force into “being”" goes WAY down on my shopping list. That had to have been written by some marketing idiot who specializes in obfuscation, not elucidation.

And Blkadr is correct in writing that you need to try different amps with the speakers you love; I too should have emphasized that.

Personally, if high-quality sound at high listening levels were important to me, I'd start with a more-sensitive speaker.