Speaker wire size VS speaker size. Should bigger speakers use bigger wires?

Speaker wires are important, bur an overkill is surely not needed.
Depending  the need of a high bass level 0.75mm2 till 1,5mm2 is usefull the rest is overkill.
For the rest: 4-pole calculations will clear everything.
regards
Ton

randy-11 has it right.  I would only add that paying attention to the conductor and dielectric quality as well as connectors on the cables can/do make a discernible difference.

One surprise for me was when I got my Vandersteen Treo CT speakers with their low 85db efficiency, my very heavy gauge "Earth series" cables from Audioquest made with lots and lots of very pure copper lent a mid bass "thickness" to the sound.  Moving to Paul Laudati's Clear Day silver cables opened up the sound, ridding my system of that thickness and revealing smooth treble detail that I had believed the carbon tweeters were capable of but I didn't know what I had been missing until inserting the Clear Days into the system.

One thing however, in support of randy-11's statement about efficiency, I had to buy the Clear Days with the most silver, the double shotguns to accommodate to the low efficiency.

My Infinity speakers can drop below the 4-ohm range from what I read quite a few years ago.  I guess their really large Kappa 9.1 series 2 dip way below, maybe even to the 2-ohm range.  The Infinities make an amplifier work that is for sure.  I cooked a Yamaha MX-1 and a Krell KSA 200s with them.  The 300cx makes them sing. 
-John

Based on what I read, wire size selection should be based on how low in impedance the speaker system goes.. My totem hawks are more listenable (more punchy bass) with belden 10awg than with kimber 4pr 14awg.  The opposite is true with my wharfedale denton.

Its the purity of wire (i like copper)  and the design that make a wire great size is not as important although again it depends on the design.Good luck.

@jsd52756 - If you like "messing" with things take a look at...

http://image99.net/blog/files/d048bbacfce9bcad4a025be804771d9a-76.html

http://image99.net/blog/files/be8de0c383c5434907610d6b55049e69-75.html

http://image99.net/blog/files/4127b5fe2694586e383104364360373b-74.html

If you want a second opinion about the eprofrmance of the Helix cables - contact Agon member @toddverrone - he’s built all of the Helix cables - including a bi-amped version we developed together and he likes them a lot

These links explain some of my thoughts pertaining to the reasons why I think Helix cables work so well
http://image99.net/blog/files/af7344cfd857b845519b34ad829c12d0-3.html

http://image99.net/blog/files/a8fe12e6b9c434f03264a1a90f441ff7-62.html

Hope you find it useful

Cheers

Assumption here is that thin wires will somehow change bass-treble balance reducing bass because of higher bass currents.  I'm not sure it is true.  Voltage divider will still be the same for all speakers - bass/midrange/tweeter  as long as speaker impedance stays about constant.   I'm not sure you can notice 0.9% loudness reduction (gauge 16), but if you can it will be for all speakers in the same percentage -  should not change the sound.  Also, the lowest impedance might be at different frequencies - even at 20kHz.  Uneven speaker impedance with resistance in series (thin wire) can affect (smear) the overall sound - not only the bass, but tube amps have output impedance of few ohms and nobody complains about the sound (or poor bass).

Interesting stuff above.  It just seemed to me bookshelf size speakers could use smaller gauge whereas if I had Wilson Alexandra hunkin-momma size speakers they would need a lot of juice.  I may try the low side of the Monster cables on the woofers and see if I notice a difference.  Or even a difference I like. 
The whole thing came about as just a test/trial of the Dueland wire.  Every once in a while messing with things is kind of fun. 
-John

@jsd52756 - I once thought thicker was better - then I tried KLE Innovations gZero6 speaker cables and they changed my thoughts forever..

They were thin comapred to the 10 gauge Van den Hul I was using, but beat the VDH for bass performance - deeper and more precise

I now use a 16 gauge cable and have great bass response

For commercially available products I highly recommend all KLE Innovations cables

I now use my own DIY cables
http://image99.net/blog/index.html

Regards...

Gauge 22  resistance is about 0.016 ohm/ft.  Your cable is 8 ft making it 8ft + 8ft =16ft.  16 x 0.016 ohm = 0.26ohm.  Assuming 4ohm speaker it will make  4/(4+0.26) = 0.94.  It means about 6% voltage drop resulting in about 12% power loss.  This power loss is equivalent to about 3.5% in perceived loudness change.  For gauge 16 cable perceived loudness drop will be 0.9%

On the other hand while 16ft of gauge 16 is 0.064ohm inductor in series with the woofer is at least 0.1 ohm.

Gauge 18 copper wire at 20kHz has still 100% skin depth, but thicker wire has slightly lower inductance.  I don't see reason going below gauge 12, but Acoustic Zen does.  My AZ Satori Shotgun has overall gauge 6.  It is divided into multiple isolated strands.  I suspect they wan't to avoid skin effect, but why gauge 6  (0.004 ohm/ft)? Perhaps they want to lower inductance.  Gauge 6 wire has reactance of about 0.9 ohm at 20kHz, 1ohm for 16 gauge - only 10% difference but it plays some role.

wire size relates to current delivery (resistance of the wire goes up as dia. goes down, on a per unit length basis)

the size of the speaker per se is not an issue; it will depend on the efficiency of the speaker and the SPL you want (another factor is the type of speaker design - cone/electrostatic/planar magnetic)

solve all your problems by using monoblocks set near each speaker...

If I were you, I will try small and bigger Cables, audience has thin speaker cables, and Cerious tech has bigger speaker cables..That's how you will find out how your speakers react to either one..