Shortcut or badcut?

@sound22card - If you think about what is at play IF you were to do this...- 

e.g. Each set of speakers has it's own cross over, so unless you implement the same model/year of speaker there will likely be differences in the signal path, which can lead to degraded sound

Different speakers will have different tones, so now the entire tone has changed and maybe not for the better

The two sets of speakers could result in out of phase signals - which will impact sound/image - sort of like a bad echo effect

These are just a few of the issues.

It really depends on how picky your are about your sound.

The "air" I currently enjoy is due to the speaker cables and the speakers I currently have.

The speakers/crossovers are tested and tuned in an independent lab to extreme levels in order to deliver the best quality sound their drivers can accommodate and the cables allow them to function to their highest level.

I would start with cables

What cables do you currently have???  

Regards - Steve

I highly doubt this will accomplish your goals and will likely create more problems than it solves.  It would help greatly if you would share what equipment you’re currently using along with a bit about your room and speaker positioning. 

It can be done, But..

Generally to accomplish doing so and getting it to perform and sound worthwhile will require 'pro sound' equipment of the sort you see at concerts. They have a whole range of devices and means to make those arrays 'do what they do'...*S*

@mijostyn has your best option, but level and balance control over the back pair (at minimum...eq added to that is a plus) would perhaps fill the bill for just sheer volume.

No guarantee as to what you may hear, however...*shrug* 

I am quite happy with the sound I have, so I will take the given advice and not mess it up with a dumb idea.  The SuperTweeter seems like the way to go, so I will $tart $aving.

Thanks for the info.  Much ....appreciated.

You will lose your sense of sound stage.