2. tech-talk
  3. 160650-148323

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
scott22 OP
262 posts
 
Pragmasi  off this topic you mention "attenuating" the signal. Which rases another question I have   The Technic has an attenuation option of 20 db on its volume control. If attenuation is OFF the volume control reaches clipping levels at about 1/2 a full turn, if the attenuation function is ON   the volume control can be used to a full turn before hitting clipping levels. I keep it on so I can have more control over the volume level.
 Do you or anyone else reading this know if attenuation at the volume control level has a negative effect on detail, soundstage, imaging. I would not think so but what do I know.  
imhififan's avatar
imhififan
2,181 posts
 
You can't have ideal world if your source is digital!
slaw's avatar
slaw
21,443 posts
 
I'm in agreement with imhififan as well.

I've tried it both ways in my system..... line level won out. Some subs are specifically designed to work with speaker level connection like REL.
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/ 
scott22 OP
262 posts
 
Mijostyn
Thank you for the advice and your time I will save this information. I'm one of those vanishing middle-class retired guys. I used the pandemic relief $$ , sold my existing system from 1980 and some camera gear to buy newer gear, from local sellers on Audiogon. I wanted to give stand speakers a shot as wife was not fond of the big Snells(sad to sell them). 
I must admit the new system just blows away my old gear in all respects except volume which is still fine it is plenty loud the Jamo c80 came with the Cantons( love their sound) and are just OK as filler in my compromised(read married) listening room. Chairs go here, sofa there, plants up there, the coffee table... I have moved that out for a clear line of sight to the  speakers.
 I digress to the point I have to save $$ and was looking to buy a Node 2i next, next year.
Who knows what will happen in these dark times as the second wave is creeping back to the northeast. be safe stay well. 

More to discover