The ports on top seem to be a match to the main outs on the back from what I can tell from the schematics.

And your wife will be unhappy to know that the knob for USB input is the only way to control the input level of the USB section. That particular input is routed to the main bus and then the output sliders. Most mixer manufacturers don't take karaoke seriously and don't intend for us to be using their gear for our purposes. The USB inputs on most mixers are either for studio mixing setups or when a band decides to take a set break and want music to play for the crowd.

Also, any comment on the behringer 1404FX I've been using?

If you're running them at different times that will work fine. but if both are running and trying to output at the same time they will try to defeat each other.

Just a recommendation here. If there is nothing mechanically or electrically wrong with your current mixer you might want to look into a firewire/PCMCIA/USB audio recording interface (basically an ornate external sound card)
Many of these have multiple ins and outs that you could run to seperate channels of your mixer and be able to mix the way God intended.

You already have pretty much everything else you need to make it work and these are more reliable than the 1/8 jacks built into laptops.

A little secret about Behringer. Its cheap but its still good. I wouldn't recommend it for recording but for live sound its just fine.

One of my systems has a Behringer EP 2500 Amp and 1222FX mixer which have been running for years with no problems what-so-ever.

That particular system has the mixer being fed signal from an M-Audio Firewire 410 interface. Quality kicks the crap out of most over-the-counter soundcards and will end the life of most (possibly all) built in laptop sound cards. The interface allows that system to get inputs from multiple audio programs at once and even be able to take in multiple items at once to send to the computer for recording.

The main outputs on top are not an XLR however, I'm not familiar with a balanced 1/4" as opposed to an unbalanced 1/4". How do I determine the precise difference Mono?

You would have a lot better sound & a much easier time with an external crossover feeding both the subs & mains - only because you are not crossing over the tops at the same frequency the subs are so they are trying to reproduce the sub frequencies still as well running into some possible phase cancellation & loss of frequencies in some of the low end. A crossover point of 75-100 is more ideal for subs as well.
That being said, the XLR & 1/4" balanced main outputs can be used simultaneously giving you main volume control for both amps you wish to push. It will be better than using a tape out for a connection.
The computer hooks to the mixer via a USB cable only, no need for the 1/8" mini jack or anything else. The PROFX actually acts as a I/O sound interface so could be used on a computer with no sound card at all - the mixer IS the sound card!

1/4" balanced is a tip/ring/sleeve - looks like a standard headphone plug. An unbalanced is a tip/ring - looks like a 1/4" plug you'd plug into say a guitar.
I attached pics of a bal & unbal plug - notice the extra ring on the balanced plug. For the Mackie output, use the balanced on the mixer & if your amp has XLR inputs, go balanced 1/4" - to XLR (determine whether you need male or female on the amp).
You could try to run both programs at the same time, but like said they may try to cancel each other out - even if only one is sending a signal.

Easiest way to tell the difference on a 1/4 inch connector is to look at the connector.

Unbalanced cables have only one separator ring and balanced have two.

Unbalanced are capable of signal travel but are limited in their distance. Balanced are a superior choice as they are not much if any more expensive per linear foot and the second signal connection helps to cancel out interference from outside sources (such as power cables)

Unbalanced cables are often caled TS (tip+sleeve) cables
Balanced cables are known as TRS (tip+ring+sleeve) cables

The plusses (+) in the above statement would correspond to separator rings referred to in the second line of this post.

Make sense?

Thanks Lonman.

I had to disappear for a little bit.

I find that the crossover frequency depends on the Sub. Different ones like different settings for different situations. I agree with you that 75 to 100 is a good start.

I didn't address a crossover because there wasn't one mentioned in the setup. And with the setup being what it is a simple adjustable lowpass filter would suffice as well. Don't know about the cost of such an animal, though.

Bryant, go to www.mackie.com and they have a karaoke hook up guide for the pro12..it's easy enough to follow...this would avoid all the comfusion...

Great info Lon, I knew you'd jump in here sooner or later.

When you say 1/4" to XLR. Just curious why that would make a diff. as compared to bal. 1/4" on both ends, as it's only the end that is adapted and not the continuous length of wire. Think I read that somewhere?

Only because of a better connection with the XLR - you could use a balanaced 1/4" on the amp input - provided it has them. You haven't listed the models of the amps yet as well & some amps don't have balanced 1/4" inputs & you don't really want to mix a balanced with an unbalanced if at all possible.

It really wouldn't, not enough to really make a difference. It is still the same signal. You can get cables that have an XLR on one end and a TRS on the other so you don't have to adapt. The more often you adapt the more signal you lose.

Yup, I been there all day but still wanted input from you guys. And thanx for that (input) as well.

i'm not knocking Behringer out, but soundwise i prefer mackie's over anything, and price wise it's reasonable, and talking about amps, i also prefer crowns, i have 2 crown amps the CE1000 which i have my ( 2 ) 3 way JBl Soundf Factor hooked up , and CE2000 where my (2 ) subs are connected via Subsonic Harmonizer with a built in Subs connections, this way i dont have to use any crossovers or any eq's all these are connected to my mackies CFX 12 with channel assignable feature..which i assigned all the vocals to channels 1/2 and the sounds assigned to channels 3/4,which i can control thru my main fader, and my 2 stage monitors assigned to aux/send 1&2 by themselves and with their own volume control..

Isn't channels 3/4 for mic inputs though?

no,on a mackie cfx 12 board ,you can do either, you can have the music running on 1/2 and the vocals on 3/4.. both have their own fader thats whats good with assignable channels you can choose whatever channels you wanted.

Not disagreeing with you by any means. I love Mackies. If I had the money to afford them for my systems I would. My preference over them is Soundcraft or Allen & Heath. Even then not every Soundcraft. I have my subs running off one of the Crown CE2000 amps and it sounds very good.

There are several good amps on the market. I listened to many of them back to back. The Behringer had just as good a sound as nearly any of them and was the lowest cost. Without real measuring equipment I will guarantee not too many people can tell the difference between them. Don't misunderstand. I love other brands and there were others that sounded better but I didn't see why I would spend that much more money for something that didn't sound that much better.

yes thats true some people might not be able to tell, but i'm pretty sure i could ( i have bought a few of them, i had 6 of them at one time) peaveys, mackies, qsc's,non of them in my opinion sounded better than the 2 crowns i have, not even the mackie amp. ( and i love Mackies ).. i have listen to Behringers, as a matter of fact i bought a Behringer board a while back and it was cheap like you said ( just can't remember the models name, i know it was a digital one ) it just didnt have the sound i was looking for, it didnt sound good to my ears, so i ended up selling it to a friend of mine after a few days, and they like it..same thing with subs, there are subs that has a short throw and a long throw, and i'm pretty sure that most people buys a sub w/o knowing what kind of subs they're buying..( thats another topic :g:g:g)

He is talking about subgroups which the PROFX does not have.

love it
 

I have mackie DFX12 and I love it. I tried other boards but they dont sound the same, gains are not as nice. I love my mackie sound and so do my customers!