Hey all, planning otop 12's and t30's

[turbovolkswagen]

Hey all,

A little background on me, I started spinning about a year ago. I'd like to start doing shows around here, but all the local sound systems are absolutely terrible. I had thought about renting, but then decided that I'd rather just have my own system. I play drum and bass, and some house.

I stumbled across BFM on djforums. I was intrigued by what I saw. I'm no stranger to sound systems, I did sound for a friends band for about 4-5 years in the tristate area.

Anyways, I've decided that I'd like to build my own BFM system. I decided to start the otop 12's first, as I already have a mackie powered sub. I'm going with the kappalite driver and the melded array. If the numbers are correct on audience size, I shouldn't need more than that for tops for quite a while.

After I get those built, I think I'm going to build some t30s, again with the premium drivers.

I bought the plans the other day and started on the front baffles, as that is the part that intimidated me the most. I bought some really crappy plywood to practice on, and it came out alright.

I have a quick question about amps though, it seems many people recommend the crown xti series. Ive read that a single xti4000 will drive an entire system. Am I wrong that it is only 2 channel? Are people running tops mono on channel a, and subs mono on channel b? Or what? This doesn't seem like something I would want to do...

[SeisTres]

Yes, a single xti will power the whole system in mono. Like you said, tops on one channel and subs on the other. Regardless of the amps I use, I always run mono as for pro sound I found no real advantage to stereo.

[netwerks]

I have a quick question about amps though, it seems many people recommend the crown xti series. Ive read that a single xti4000 will drive an entire system. Am I wrong that it is only 2 channel? Are people running tops mono on channel a, and subs mono on channel b? Or what? This doesn't seem like something I would want to do...

Yes. You can run a pair of BFM tops on channel a and 3 pair of subs on channel b safely, I do it all the time and a XTI 4000 will be coasting even at full power.

You could theoretically run 4 tops on one channel (2ohm) and 8 subs on the other (2.5 ohm) but i wouldn't do it unless I had a spare amp at the gig or you are not running the rig hard. Better safe than sorry.

[Bruce Weldy]

You could theoretically run 4 tops on one channel (2ohm) and 8 subs on the other (2.5 ohm) but i wouldn't do it unless I had a spare amp at the gig or you are not running the rig hard. Better safe than sorry.

Four tops - yes
Eight Subs - NO, unless they are 16 ohm cabinets or you wired them in series.

4 - 8ohm loads is 2 ohms

And if you are figuring 10 ohm loads - 4 - 10s is 2.5. Not 8 - that would be 1.25

[SeisTres]

LOL, I think he meant to say 4 subs, not 8.

In other news, I heard Ron K runs his 24 t24's all paralleled off a single bridged amplifier




(Note: Ok you got me, I made that last bit up)

[turbovolkswagen]

Cool thanks for the tips guys. Am I correct in that the only difference between the 1000,2000,4000, etc is the power ratings?

If that is the case, I think I could get away with the 1000/2000 for the tops and use my powered sub for now? Then when I build the tubas, get a 4000 for them?

I really want to retain stereo for the tops, As Lots of my music has sweeps and effects that pan left to right.

(Again, i'm wanting to use the kappa drivers for everything still, I've heard they sound much better)

[Bruce Weldy]

I really want to retain stereo for the tops, As Lots of my music has sweeps and effects that pan left to right.

That's nice, but in most situations, only 10 percent of your audience will hear the stereo effect - the other 90% will get only half of the stereo spectrum and think it sounds crappy.

Go mono - it will sound better to the majority of the audience. Then when you get home, put on the headphones and enjoy all the stereo nuance with a cold beer and a nice cigar.

[turbovolkswagen]

Makes sense I guess, it's just weird to me, i've always done stereo for live sound. I've also stood in the center for sound checks though too haha. Well mono would be cheaper, easier and apparently sound better too. I'll be sure to make a build thread once I get rolling. Thanks again for the help.

[netwerks]

You could theoretically run 4 tops on one channel (2ohm) and 8 subs on the other (2.5 ohm) but i wouldn't do it unless I had a spare amp at the gig or you are not running the rig hard. Better safe than sorry.

Four tops - yes
Eight Subs - NO, unless they are 16 ohm cabinets or you wired them in series.

4 - 8ohm loads is 2 ohms

And if you are figuring 10 ohm loads - 4 - 10s is 2.5. Not 8 - that would be 1.25

Sorry that was a typo I mean 4 subs per side I dunno what the hell I was doing.

[Bruce Weldy]

Sorry that was a typo I mean 4 subs per side I dunno what the hell I was doing.

You are forgiven....go forth and sin no more.