subwoofer to speaker connection


I am a novice and would like to seek advice from fellow Audiogonians. In  reading the forum 128025-84361 (Jan this year) on speaker and sub connection, I am intrigued  by the comment   from rcprince “Virtually every review I have read remarks on how the mids and upper bass from the main speakers are improved when you add a subwoofer…”. I have a pair of Focus Audio Signature Series (Model 78) speaker and one Audio Physic Luna sub. Would connecting these 2 produce improvement in the sound of music? If so , how  can I  best connect my sub and speaker ? I don’t mind buying the high pass filter and inline cross over as mentioned in the above forum, if needed. Moses


moses189
Thanks for your comments, gdnrbob.  I wonder if anyone would like to further comment on future upgrades of my system since spending $1500 for  another Lectron JH50 amp will not provide any tangible gain in the sound (to be used as monoblocks) after adding my sub+high pass filter, what would be the next upgrade that you would recommend: change  my  Audio focus (Signature series model 78) speaker, or Transcendent Grounded Grid Preamp, or  Linn sondek LP12  turntable with Karma cartridge?
Why not try out what you have and see if it makes a difference before you make your next move?
 I have tried the sound with and without  the Hsu bass optimizer.  I found that  combining my subwoofer with Hsu bass Optimizer with cross over at 60 Hz  to my amp,produced the music a fuller range.  The base part is especially better when listening to organ music  and a clearer voice when listening to Pavarotti singing. Any suggestion as to what would be a further worthwhile upgrade to explore with my system. 
I just ordered a Hsu high pass filter. I'll let you know what I find. It may be what you are looking for.
Without knowing what sound quality you like makes it almost impossible to give you suggestions.
If you are near local dealers, I would suggest listening to as many speakers as you can, so you can get a handle as to what you are looking for sound-wise. Then we can work out what electronics you need.
I wish I heard Audio Focus, but I never have.
B
I am glad to hear the improvement with the connection of my subwoofer +high pass filter. I am happy with the improvement and not in a hurry to further upgrade, assuming the next upgrade will be expensive. Will look forward to hear your experience with the high pass filter. Moses189