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[Craig Hauber]

Avoid series-parallel wiring schemes with installed subs.
If you have several series branches in parallel and one sub goes then you lose that entire set of subs.  The impedance goes up on the remaining portion of the system and your whole overall sub output drops significantly more than just that one cabinet loss.
I recommend not putting more than three paralleled eight-ohm drivers per side on an amp channel even if the amp is rated for 4 (2-ohms)  I prefer my installed amps to be run at easy loads as they will get plugged with dust eventually and that extra thermal headroom will keep them running longer. (Likewise with easier loads the fans spend less time at their highest speed and dust takes longer to pile-up)
I also like splitting up the sub loads through multiple amplifiers - if you have identical ones for other bandpasses having each amp running subs and tops so if 1 goes down you just lose a dance floor channel but not all your subs or all your mid/highs at once.

[Joe Brugnoni]

Ian, if money is not a major issue, maybe you should contact one of the many providers in your area that do installs to come take a look at what you have and where you want to be.

It may save you a LOT of $$$$$$$$ in the long run.

[Ian Coughlin]

I guess i have to apologize again, I put this in the basement and entitled "game" because I didn't mean for it to be as serious of a discussion as it turned out to be.  I was just looking for stupid answers like 6 per channel.  Sorry.

On a serious note, the venue in question is a great friend of mine and doesn't always do things "the right way" but rather "any way it works way" (except for rigging and safety I stand firm), and being the owner, if it makes noise (speakers) and moves around (lights) he's happy and thinks its great!  He doesn't understand or care to understand what comb filtering or impedance/resistance is.  Oh did I mention before he bough his first bar he was a DJ by trade? Needless to say he didn't loose those wonderful DJ attributes we all know and love    

In the venue http://www.socialsportskitchen.com/home.html is next to impossible to run wires, especially to the amp rack which is on the second floor.  Everything is sheet rocked and I would have to do some major cutting and snaking to get a line up there.  Three lines are avail for subs at the moment; 2 on the dance floor and 1 on the bar side.

So with that said, I (me) would LOVE too be able to rewire that entire place "the right way" and have 4 speakers, 2 per channel, per amp but thats not really an option at this point in time for the venue.  In the meantime I'm stuck with 6 extra of those RCF subs and one 12ga line.

[Art Welter]

Ian Coughlin wrote on Sat, 08 January 2011 09:39

In the venue http://www.socialsportskitchen.com/home.html is next to impossible to run wires, especially to the amp rack which is on the second floor.  Everything is sheet rocked and I would have to do some major cutting and snaking to get a line up there.  Three lines are avail for subs at the moment; 2 on the dance floor and 1 on the bar side. So with that said, I (me) would LOVE too be able to rewire that entire place "the right way" and have 4 speakers, 2 per channel, per amp but thats not really an option at this point in time for the venue.  In the meantime I'm stuck with 6 extra of those RCF subs and one 12ga line.

Decent damping factor aside, if you mean by "three lines", six conductors, it is possible to use a single "-" on most amps, that is, amps that have both sides "-" tied together.

That makes it possible to run four amp sides (two amplifiers) with six wires, one "-" and two "+" per amp. A hand full of wire nuts and away you go...

[Ivan Beaver]

Art Welter wrote on Sat, 08 January 2011 14:12

Ian Coughlin wrote on Sat, 08 January 2011 09:39 In the venue http://www.socialsportskitchen.com/home.html is next to impossible to run wires, especially to the amp rack which is on the second floor.  Everything is sheet rocked and I would have to do some major cutting and snaking to get a line up there.  Three lines are avail for subs at the moment; 2 on the dance floor and 1 on the bar side. So with that said, I (me) would LOVE too be able to rewire that entire place "the right way" and have 4 speakers, 2 per channel, per amp but thats not really an option at this point in time for the venue.  In the meantime I'm stuck with 6 extra of those RCF subs and one 12ga line. Decent damping factor aside, if you mean by "three lines", six conductors, it is possible to use a single "-" on most amps, that is, amps that have both sides "-" tied together. That makes it possible to run four amp sides (two amplifiers) with six wires, one "-" and two "+" per amp. A hand full of wire nuts and away you go...

While I would agree that "most" amps have the neg ternimals tied together, SOME do not, and tying them together could result in damage to the amplifier.

So this HAS to be checked out-if it is an option-BEFORE trying it.

Just adding a word of caution.

[TJ (Tom) Cornish]

Ian Coughlin wrote on Sat, 08 January 2011 10:39

I guess i have to apologize again, I put this in the basement and entitled "game" because I didn't mean for it to be as serious of a discussion as it turned out to be.  I was just looking for stupid answers like 6 per channel.  Sorry. On a serious note, the venue in question is a great friend of mine and doesn't always do things "the right way" but rather "any way it works way" (except for rigging and safety I stand firm), and being the owner, if it makes noise (speakers) and moves around (lights) he's happy and thinks its great!  He doesn't understand or care to understand what comb filtering or impedance/resistance is.  Oh did I mention before he bough his first bar he was a DJ by trade? Needless to say he didn't loose those wonderful DJ attributes we all know and love     In the venue http://www.socialsportskitchen.com/home.html is next to impossible to run wires, especially to the amp rack which is on the second floor.  Everything is sheet rocked and I would have to do some major cutting and snaking to get a line up there.  Three lines are avail for subs at the moment; 2 on the dance floor and 1 on the bar side. So with that said, I (me) would LOVE too be able to rewire that entire place "the right way" and have 4 speakers, 2 per channel, per amp but thats not really an option at this point in time for the venue.  In the meantime I'm stuck with 6 extra of those RCF subs and one 12ga line.

The problem with series wiring of anything is that the supply's voltage gets divided across the whole load.  Sure, you can be creative and make 8 subs look like one 4 ohm load to the amp,

+ --------
|  8 8 8 8
|  | | | | = 4 ohms
|  8 8 8 8
- --------

but each sub gets half the voltage potential of the source, so unless you find an enormous amp, you're not going to be able to drive the subs very hard.  On the plus side, you're not going to blow up a lot of subs if you leave 12dB on the table.

If you were inclined to invest the time, you could calculate the relative output of several cases - weighing the mutual coupling of multiple boxes at whatever power you can deliver into a series-parallel system vs. "correctly" powering the system using more than one amp but factoring in power compression.

As to your buddy's particular build situation, maybe the extra subs would make it seem louder to some folks, even if they aren't powered.