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What is going on with PA+
Posted: Sun Jun 02, 2013 5:30 am
by Michael Murphy
Guys, last week I lent out a jack from the system, this is how its cabled up
Left channel from the mixer,(master out) balanced 1/4" out to xlr, to the eq channel 1
Right channel from the mixer, (master out) balanced 1/4" out to xlr, to the eq channel 2
Eq channel 1 out to left sub input on PA+, xlr to xlr
Eq channel 2 out to right input on PA+, xlr to xlr
Left low output from PA+ to Amp1, xlr tl xlr
Left high output from PA+ to Amp 2, xlr to xlr
Amp 1 driving 2 T39's from 1 side parallel wired
Amp 2 driving 2 OT12 from 1 side parallel wired
Ok so guy brings back cable but its the wrong one, I had pulled and lent him the left channel master out 1/4 balanced to xlr jack.
I figured as much as I was in the shop Id play the system a lil with out bass. Plugged in the phone as source to the mixer as normal and low and behold the bass cabs were playing??? Not as loud as normal but they were getting a signal. I switched off the tops from the PA+ and was listening to the T39's and I could here some intelligible in them...like vocals you can understand... which should not be there because of the x-over and why or where is the signal comming from to even get the bass amp to play with the entire left master out cable missing

Re: What is going on with PA+
Posted: Sun Jun 02, 2013 6:27 am
by DJPhatman
Crossover setting issue. Read the manual on how to set the PA+ for 2 way operation (tops and subs). Use a decent crossover slope to tame the rising response to the sub.
Re: What is going on with PA+
Posted: Sun Jun 02, 2013 7:04 am
by Michael Murphy
Well i figured out the signal thing, even though there is no channel 1 input signal on the eq there is an output signal. I though channel 1 and 2 were completely indépendant, oh well. And the lp on the sub is 90hz BW 24
Re: What is going on with PA+
Posted: Sun Jun 02, 2013 8:40 am
by Bruce Weldy
pumpsfast wrote:Well i figured out the signal thing, even though there is no channel 1 input signal on the eq there is an output signal. I though channel 1 and 2 were completely indépendant, oh well. And the lp on the sub is 90hz BW 24
There is no reason to have two inputs to the Driverack. Take one master out (L or R, just make sure and pan all material that direction) - then to one EQ channel (having two just makes it harder to adjust), into the L input of the PA+, then use the high and low outs to go to the L and R channels of the amp.
Re: What is going on with PA+
Posted: Sun Jun 02, 2013 9:11 am
by Ryan A
Bruce Weldy wrote:
There is no reason to have two inputs to the Driverack.
That is, unless you want to run a stereo setup. I always like to run stereo with recorded music, with the exception of the subs which get a summed mono signal.
Re: What is going on with PA+
Posted: Sun Jun 02, 2013 10:12 am
by Bruce Weldy
Ryan A wrote:Bruce Weldy wrote:
There is no reason to have two inputs to the Driverack.
That is, unless you want to run a stereo setup. I always like to run stereo with recorded music, with the exception of the subs which get a summed mono signal.
True, but he's not running stereo.
Re: What is going on with PA+
Posted: Sun Jun 02, 2013 11:01 am
by Michael Murphy
Makes sense, why did i buy à 2ch eq?, oh yeah i remember now, what was i thinkin

Thanks guys PS the ot12 tops are freakin amazing, i want 2 more!
Re: What is going on with PA+
Posted: Mon Jul 08, 2013 8:46 pm
by ripNdeb
Ryan A wrote:Bruce Weldy wrote:
There is no reason to have two inputs to the Driverack.
That is, unless you want to run a stereo setup. I always like to run stereo with recorded music, with the exception of the subs which get a summed mono signal.
Sorry to bump an old thread but, this question keeps coming up at church: They insist on running stereo. How do they do it with their PA+? Do they need to get another one?
Re: What is going on with PA+
Posted: Mon Jul 08, 2013 10:22 pm
by Bruce Weldy
ripNdeb wrote:Ryan A wrote:Bruce Weldy wrote:
There is no reason to have two inputs to the Driverack.
That is, unless you want to run a stereo setup. I always like to run stereo with recorded music, with the exception of the subs which get a summed mono signal.
Sorry to bump an old thread but, this question keeps coming up at church: They insist on running stereo. How do they do it with their PA+? Do they need to get another one?
All driveracks can run stereo with no problem......no reason for a second one.
Running stereo in a church is asinine. People on the far left and far right will never hear the other speaker.
Re: What is going on with PA+
Posted: Mon Jul 08, 2013 11:53 pm
by ripNdeb
Bruce Weldy wrote:
All driveracks can run stereo with no problem......no reason for a second one.
Running stereo in a church is asinine. People on the far left and far right will never hear the other speaker.
I should have mentioned they also run aux fed subs

Still possible with one? I would imagine, if properly crossed over, aux fed subs is unnecessary.
Re: What is going on with PA+
Posted: Tue Jul 09, 2013 12:18 am
by BrentEvans
ripNdeb wrote:
I should have mentioned they also run aux fed subs

Still possible with one? I would imagine, if properly crossed over, aux fed subs is unnecessary.
Nope. DRPA only has 2 inputs, so you can do stereo, or mains+subs.
Ashly 3.6, DCX2496, or other more expensive ones would be your options for a single box.
ripNdeb wrote:
Bruce Weldy wrote:
Running stereo in a church is asinine.
It can help you get gain on choir mics, among other things. You pan the right mic to the left speaker, etc. Nobody in the crowd knows the difference except that it's louder.
Re: What is going on with PA+
Posted: Tue Jul 09, 2013 6:10 am
by Bruce Weldy
BrentEvans wrote:
It can help you get gain on choir mics, among other things. You pan the right mic to the left speaker, etc. Nobody in the crowd knows the difference except that it's louder.
Brent, I know you are a pro and do HOW on a regular basis. But, most churches, even if they have a "real" sound man, often have to rely on volunteers. Dealing with aux-fed subs and stereo can be a disaster waiting to happen in the wrong hands.
Now, if it's a mega-church with well-paid pros that are there every service - fine. But, that's just not the majority of HOW situations out there. Personally, I'd just as soon have the system crossed over correctly, have high pass filters on every channel to keep crap out of the subs, and run mono so that things don't get screwed up.
Using aux-fed subs also negates the auto EQ on the driverack and requires an additional RTA for setup and additional EQ for the subs.....I just don't see enough benefit (actually, I don't see any benefit) for 99% of the churches to engage in that setup.
The church that I took over a few years back had aux-fed subs....the guy I took over for (who had gone to sound engineering school - which meant he knew everything) had instruments panned all over the place. First day, I started unraveling all of the mess of wires to see just what was what - the system was running mono. So, even a guy with "training" didn't have a clue.
I tried to make the system idiot-proof. Did away with the aux-fed subs, and tried to simplify the set-up. Everything I did was with the expectation that I wouldn't always be there and some volunteer could pull off the service with just hitting mute buttons and maybe riding herd on vocal faders.
I think too many guys that set up systems do it from their perspective as opposed to what may be best in the long run for the venue/users.
Just as setups for running sound off the stage are different than what you'd do with a FOH situation - you also have to adjust for the varying levels of expertise of the users. Which means the lowest common denominator when it comes to most churches.
Re: What is going on with PA+
Posted: Tue Jul 09, 2013 10:38 am
by byacey
Bruce Weldy wrote:
the guy I took over for (who had gone to sound engineering school - which meant he knew everything) had instruments panned all over the place. First day, I started unraveling all of the mess of wires to see just what was what - the system was running mono. So, even a guy with "training" didn't have a clue.
I can see hard left or right panning if using the subgroups, but if he had varying degrees of panning between the channels, I wonder what he was hearing through the mains while cranking the pan controls?
That's an interesting idea that Brent Evans presented for a choir, although usually monitors are more of a problem for feedback rather than FOH; I suppose in a smaller room it could become an issue. I have found sometimes reversing phase on some of the choir mics helps combat LF and Mids feedback, depending on the mic spacing.
I agree, stereo is a waste of time more often than not. Perhaps in a soft seat theater for effects and audio illusions etc, In most cases making everything heard well by the audience is job 1.
Re: What is going on with PA+
Posted: Tue Jul 09, 2013 6:10 pm
by BrentEvans
Bruce Weldy wrote:
Brent, I know you are a pro and do HOW on a regular basis. But, most churches, even if they have a "real" sound man, often have to rely on volunteers. Dealing with aux-fed subs and stereo can be a disaster waiting to happen in the wrong hands.
I agree that aux fed subs is overkill in most smaller churches. That said, there are ways to keep small unmanaged HOW installations sounding pretty good. Many problems can be corrected by attending a service or two, and putting little sticky dots all over the console where the pots are supposed to be, then charging a church leader with keeping the lines on the dots. Keeping choir mics panned correctly is a good application for that.
Another thing that works well is a simple snapshot of the console, be it with Polaroid, cell phone camera, or digital recall.
Re: What is going on with PA+
Posted: Tue Jul 09, 2013 6:49 pm
by byacey
Brent, Just out of curiosity, what kind of mics are you using for the choir?