Wire second sub woofer driver in series or parallel ?

[jtrade]

I have acquired a second JBL Digital 10 sub woofer with a defective plate amp (lady seller :"It just stopped working, so I bought a new one").

I wanted a second sub as I blindly believe those who say a two sub setup is better/more balanced than one.

As I usually drive a sub via Speakers 2, to avoid the Speakers 1 signal passing through unnecessary electronics, my intention is to simply connect the second sub driver in series or parallel to the first, ie. both powered by the one working JBL plate amp.

Assuming the JBL drivers are at least 8 ohms (I won't see until I open up the cabinets, as it's not on the spec sheet), is there any preference sound wise to wire in series versus parallel ?

I am not concerned about power output as I use the sub(s) at very low, barely audible levels, just to "pressurise" the quite large room.

PS. I may use the defective plate amp as my first electronics repair project, as per my other recent thread !

 

[Julf]

If the plate amp has been specifically designed for that sub, it is probably optimized for the impedance of one element. Connecting another one in parallel, you halve the impedance - and we don't know that the amp can handle that. Connecting in series is always safe (for a semiconductor amp), but might result in lower output power.

 

[jtrade]

Question 2 : wire in or out of phase (I have seen it suggested that when using two subs, it makes sense to wire them out of phase) ?

I guess the obvious answer is to use my ears...

 

[Julf]

Question 2 : wire in or out of phase (I have seen it suggested that when using two subs, it makes sense to wire them out of phase) ?

I guess the obvious answer is to use my ears...

Not sure what the benefit of out of phase would be.

 

[jtrade]

It allegedly may help cancel room nodes...

Edit : some suggest to wire both subs in phase but out of phase with the main speakers; others say wire the subs out of phase to each other (so one is in phase with the main speakers).

 

[juz400]

It allegedly may help cancel room nodes...

Edit : some suggest to wire both subs in phase but out of phase with the main speakers; others say wire the subs out of phase to each other (so one is in phase with the main speakers).

I think the phase issue is more to do with distances from the main speakers and the drivers canceling each other out

 

[Julf]

I think the phase issue is more to do with distances from the main speakers and the drivers canceling each other out

Indeed. So I would start buy wiring everything in-phase, and then if an analysis of room response shows you have a dip at a frequency corresponding to the distance between the speakers, you can try reversing the phase.