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Best method to connect subwoofer to amp

I just finished a great post about my speakers and amp clipping sensitivity, impedance etc. highly educational, as I am a rookie in this hobby just starting out. One recommendation coming out of that discussion was to contact my manufacturers. I have a Jamo c 80 sub (1800 watts and with an adjustable crossover from 0 to 200hz) for two-channel stereo. the c80 has binding posts for speaker cable connections for spades and banana plugs. The c80 also has" Line in left/LFE and right.. My integrated amp is a Technic SU-G700 and its manual says to connect the sub to its pre-out left and right connections.
Listening to Paul McGowan ( PSAudio poobah) he says the best way is to run speaker cables from my amp to the speaker terminals on the JAMO which is my current practice. He says this ensures the same signal going to my main speakers (Canton 9k stand-mounted) and the sub are the same helping them disappear. As noted I am currently using that method and indeed my subs vanished.
However when speaking to JAMO the rep said the best way is to connect the amp and sub is through the Preout of the amp to the Line input Left /LFE and right of the sub, my Technic manual also says this.
There is no high pass filter involved in my system the integrated amp sends the full signal through the pre-out not confirmed by Technic but from what I’ve read. I mention this as my amp is only 70 watts and I would have loved to separate the bass to be driven exclusively by the sub so my main speakers could be relieved of that duty and as I understand it two benefits would occur 1 my stand-mounted Cantons would no longer have to play the bass and 2 more power would be available for the cantons.
It should be noted the canton9 k have two sets of speaker terminals on set for medium and high frequencies and another set for bass. I will not be buying a separate highpass filter at this time.

Given the above which is the best method (for musical benefits) to connect the sub or does it even matter which of the two options I use given my system?
Is one method safer to use than the other?
Am I missing anything I should be aware of?
Thank you for your help
Scott


scott22

Showing 2 responses by mijostyn

mijostyn's avatar
mijostyn
8,570 posts
 
Scott, I am also in the Northeast. If you are over 65 just keep your distance from others. Skip the concerts and those late nights at the bar for now. This is all going to blow over. I think the main attraction here is they way this is permanently going to change the way we live. People who never shopped online are now addicted to it. Malls are going to converted to nursing homes, retailers are disappearing. People working from home are more productive! Sure, if you done have to waste 3 hours a day in the car. Downtown real estate is plummeting in value. Who needs a big expensive office. 
Anyway, sad to hear you sold your Snells. Those were great speakers.
If you want to increase your output get a crossover like the JL Audio unit and a second subwoofer. This will allow you to raise the crossover point without harming the image as long as you place the subs correctly. I cross over at 125Hz. It is easier to match subs with a higher crossover frequency because the wavelengths are shorter. The low crossover points that you see being used work better with one way crossovers and single subwoofers. It adds low bass but does nothing else for the system. Using a 2 way crossover, two subs (or more) and a higher crossover point reduces distortion in the main speakers, increases headroom and gives you much more flexibility in adjusting the bass to your preference. 
  
mijostyn's avatar
mijostyn
8,570 posts
 
Scott, I know you said " I will not be buying a separate high pass filter at this time." But, I am a notorious PITA and have been using subs since 1976 in every conceivable configuration always trying to match them to one type of planar dipole or another. You can not attain the full benefit of subwoofers without an adjustable 2 way crossover that has a  speaker delay function. Room control is a useful additional benefit.
Sometimes the best solution is just not attainable usually for financial reasons. This is always the case for me. This makes our systems evolutionary which is fun and we get to appreciate each additional improvement to the fullest extent. I always know what the next evolution is way ahead of time.
I find that people tend to use shortcut solutions in audio thinking that somehow they will come up with the ultimate solution (without spending a lot of money) I certainly have been guilty of this. But, relative to a dedicate subwoofer management system the other alternatives are seriously inferior. Certainly you may need to use one for the time being. But, know that if you are looking for the highest performance you will need to make the jump at some point by either getting a separate cross over like this https://www.parts-express.com/behringer-dcx2496-ultradrive-pro-digital-24-bit-96-khz-loudspeaker-man...
Or switching to a preamp that has this function like this https://www.deqx.com/products/premate/ 
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