Delayed in-fill speakers from QU 16

[WaihekeSoundieParticipant]

Ah…yes, I see: of course you still want everything in the main mix 🙂

But cutting everything out of the Main Mix using the GEQ is as effective as using two crossovers for main and sub with same crossover freq and slope? Less to go wrong.. less processing in the chain as well.

So how do you tune this setup?
For someone with my equipment I guess using my ears? Put some full range recorded music.. cut the lows in the main mix.. send it to the sub out mix post fade at unity gain on those channels and bring up the sub out master until it sounds nice and balanced .. or maybe use a tone sweep? thereafter use the dca to control overall volume. That about it?

But do you adjust the level of the instruments in the sub out mix or just leave on unity? Guess you do at setup but tend to leave mostly alone afterwards ?

And what goes in the sub out mix if I have high passed the mains at 70hz say? Bass, kick, stomp, keys/synths, iPod/DJ would that be it?

Sorry for such long questions.. your help is very much appreciated.
Andy

[dpdanParticipant]

Hi Andy,
I think you got it 🙂

Cutting the frequencies for the L/R mains on the graphic EQ is not as accurate nor nearly as steep as we like a crossover to be, so the DBX processor would indeed make this better but….. noticeably? I doubt it. The only crossover we are really talking about now is the relationship of tops to subs. Since your JBL sub has a set crossover frequency of 90 hertz, I would still suggest cutting the lowest 5 bands on the Main L/R EQ…. 31.5, 40, 50, 63, and 80. Of course if you do sound for a gospel quartet and you have a bass singer that reaches notes below 80 hz. you may want to run his mic into the subs a tad but definitely use a high pass filter on his mic…. whatever it is 🙂

Now, on a completely different subject, I highly suggest getting a Shure Beta 52A kick mic if you don’t have one already, I have used just about every mic known to man for kick and no other mic performs this task better in my opinion.

When I click on the blue MIX button for subs (9) in my setup, I have all the desired channels set to unity.
I do run the floor tom into subs too. I almost never revisit the subs mix to change levels, but when a ballad comes along, I almost always want to pull the subs level down, the last thing that is important in a great ballad mix is a heavy metal kick drum.

I suggest always trust your ears. A sweep will only tell you that your gear is working, but it won’t indicate what the quality of sound is like. You will probably find that your main L/R master fader will be lower than the subs, unless you have a setup where you have an enormous collection of subs 🙂 I always run some music that I am familiar with through my system to make sure that it sounds prestine. Try your best to stay away from a lot of EQ, and same goes for compression and gating… in fact as far as gating goes, I would only suggest using it if it works well enough, but don’t kill all the detail that the drummer may be doing on the snare.

Also, get this free app for your iPad or iphone… it’s wonderful.
It is called feedback detector.
Here is a quick youtube video I made describing how to use it.

[WaihekeSoundieParticipant]

Hey @dpdan,

Thank you very much indeed.
Ok I’ve got that now. I have set it up and practiced with it using recorded material and have a/b ed it with a standard crossover arrangement through my DBX DRPX. Soundwise I would say that it is no worse than through the crossover with this material and is more flexible obviously. Only downsides (that I can see) are the extra care required in set up and that switching to the custom layer to change overall system volume is a bit awkward and I can see that I could well reach for LR and adjust that by mistake in a gig — but I would get used to it. Would be nice to have dedicated sliders for the DCAs like the larger QU’s have I beleive.
Thanks for your help with this. I was pretty confused. Much appreciated!!

I use a Heil PR40 for my kick but thanks fro the tip- I will check out the Shure Beta 52a when I get a chance.
And thanks for the app tip.

Generally I mostly have feedback under control but now and again a particular venue or band will turn out to be a complete nightmare. In soundcheck it is reasonably easy to track things down — I can mute channels and mixes to figure out the source and mixes involved and I can use an app such as you suggest, or the RTA or pull up/down frequencies in the main’s GEQ or PEQ to isolate the problem frequencies.

However sometimes sound check is kinda ok but when the show starts and the instruments turn up you have problems. On one loud gig recently in a lively hall a band I do sound for quite often had a horrible very high freq feedback >4k that would come and go and was really hard to track down. The band was a acoustic guitar through amp on stage miced, 1 main vocal + 2BVs, acoustic drums with main elements miced, bass and elec guitar (cab miced) and they were doing a very loud driving country rock / blues.
The 3 monitors were loud as the guitars were very loud on stage. Could I find this feedback??? The feed could have been in any of the monitors or FOH.. I can’t ask them to stop and I can’t really turn stuff off. I can apply cuts to the mixes and see if it goes away.. Is there a good strategy for this or any tips? What I didn’t try was soloing the mixes in headphones to try to figure which mix it was in- that would have been sensible… what do you do when this happens? Very frustrating…

Thank you 🙂

[dpdanParticipant]

“The 3 monitors were loud as the guitars were very loud on stage. Could I find this feedback???”

This is another reason why I assign ALL the monitor mixes (not in ear mixes) to a single DCA and label it ALLMON.

When feedback rears it’s ugly head and I don’t have a clue where it is coming from, I grab the ALLMON DCA and lower it just a few db and that usually makes it go away. When I have time after dialing in the song that is currently playing, I figure out what was causing the feedback, and then carefully return the DCA back to unity.

Yes, I agree about the inconvenience of the DCA not being on the main top layer, but we are not likely changing the level of that DCA very often anyway, and you are correct, you’ll get used to it. Of course you can still move just the Main L/R master or subs or delays without using the DCA, the DCA juts acts as a remote control of all the faders that are assigned to it. Just remember that audio does not pass through a DCA fader like a group fader does.

What part of the world are you in? I feel like I know you now 🙂

[Anonymous]

@dpdan
Waiheke is a little island just out from Auckland the City of Sails in New Zealand. 🙂

I did read somewhere that A & H were to introduce the new remote controllers into the QU / GLD series.
I wish they would hurry this along!

[WaihekeSoundieParticipant]

Great idea to put all the monitors on a DCA Dan, Thanks so much 🙂

Yeh I know what you mean about getting to know. It has been very helpful. Many, many thanks.
This is me on Facebook. https://www.facebook.com/andy.lewis.39750
With a couple of pics of the shows and bands I’m involved in.

Yes, Waiheke is an island with about 14k permanent residents just off Auckland, NZ.
https://www.google.co.nz/maps/place/Waiheke+Island/@-36.7930897,174.9521539,11z/data=!3m1!4b1!4m5!3m4!1s0x6d72c882cf34cebd:0xcb6ce79667d0cc2c!8m2!3d-36.8019237!4d175.1080146

Where are you guys based?
I think that everyone from the forum should come visit Waiheke!!

[dpdanParticipant]

xyz,
what “new remote controllers” do you speak? 🙂

Waiheke,
WOW a beautiful place to live 🙂

I am in St. Louis, Missouri USA

[Anonymous]

IP6 & 7
I read it on a brochure somewhere?
Mind you there is the iPad
The iPad saved my bacon last night at an outside job.
Ran out of setup time.. musicians were mucking around on stage… had not sound checked anything.
Ipad in hand I was able to do it all from stage!
12k right. Phew!!!
Thank you A & H for a wonderful App.

[WaihekeSoundieParticipant]

The app is very useful eh 🙂 Likes to chew battery though– I use a battery pack on a cable in my pocket and keep it plugged in

[WaihekeSoundieParticipant]

I do have one question about the AUX fed subs– i read about how changing the relative signal of the tops and sub mid performance changes the crossover point and phase and is to be avoided..
I suspect that this only really matters in large systems — to me its more important whether it sounds ok- but what is that about?

[dpdanParticipant]

Changing the level of the subs is not going to effect phase of either the subs or the tops.

My suggestion is don’t worry about things like this… in other words, don’t sweat the small stuff 🙂
I am not suggesting to disregard the phase of all your speakers, but not to worry about changing the level of the subs. Absolutely everything has to be in phase, but it will not sound phasey or anything if you alter the level between subs and tops, just run the subs where they need to be for the music genre and audience.

By the way, for years JBL refused to use what I refer to as the industry standard for polarity for their speaker components,
they made no bones about it, if you bought a JBL 15 inch woofer, it had a warning tag on the speaker terminals that went something like this….

positive voltage applied to the BLACK terminal creates a forward cone movement.

Of course this was completely opposite of just about every other speaker manufacturer in the world.

Red is always positive…. so, since your JBL sub is, well ,,, a JBL,
I would suggest calling JBL and ask them point blank, is your sub the same polarity as other brands or check it with a phase checker if you have one.

[WaihekeSoundieParticipant]

I will leave this thread alone shortly 🙂
But I just wanted to add for anyone still reading this saga — I did some investigation on using the GEQ as a HPF to emulate the slope of a cross over. It is not designed for this and is not really great– even if I drop all the sliders up to and including 80Hz it still passes a lot of lows (as low as 40Hz) to the tops– this is because the GEQ only attenuates -12db max per band. It is better than nothing but a cross over with a 24db slope is better I think.

Incidentally I did this test by enabling the signal generator on one of the spare mix outputs and physically patching it back into one of the channels — you can then send this incoming tone to the Main LR and Aux Sub mixes and have a listen to each and together as you sweep it. Very interesting to see what freq range your speakers do actually handle.

[WaihekeSoundieParticipant]

Oh- thanks Dan I just saw your post. Yep – I’m not really sweating it– just curious really.
Um– I don’t have a phase checker. I will see if I can get anything out of JBL. Meanwhile I guess I flip the phase switch and see which sounds best at the next show.
Looking forward to giving the AUX fed subs a whirl at a show. Looking like New Year’s eve unless something comes up before then.
Thanks once again man.
All the best.

[andyozParticipant]

Hi,

Reading this thread with interest as just about to try out the sub aux Send option this weekend.

Regards using the GEQ to simulate a HPF on the main LR output why not use the actual HPF available on each channel? More time to setup but surely more effective.

The Mix feed to the sub can be setup to ignore any HPF settings on the original input channels. I plan to do it that way and only use the LPF on my active subs. I’m only using a single sub to take a bit of the load off the tops so they will be running down into the same region as the Sub save maybe the last 30Hz (it’s for Pub Rock so not super critical). My tops only have a 100Hz HPF and so need it to be more like 80Hz..

Also, when you setup a DCA to control the level of the LR and sub Mix, would you just put that fader into the Custom 1 layer say to the left of the main LR fader. You then ignore the main LR fader on the right hand side of the screen (unless you want to adjust the relative LR and sub levels)

[WaihekeSoundieParticipant]

Hi,
Glad the thread has been useful. Certainly was useful to me.
Regarding your comment
>> “.. using the GEQ to simulate a HPF on the main LR output why not use the actual HPF available on each channel

Regarding the use of HPF on the input channels. You can do that and you should anyway on relevant channels because most 12″ or 15” tops will go down pretty low and you don’t want rumble and plosives in the tops any more than you want them in the subs.

The idea of using the GEQ was to achieve the crossover but I think I get a better result when I use a crossover rather than the GEQ to high pass to the tops. The GEQ does not really shelve the signal all that well. Also I think I like the sound more when I use another crossover with the same slope and crossover frequency as the one feeding the tops on the AUX Sub channel to low pass to the subs. It is a wee bit more wiring and gear but I think it sounds better. This is think is the “recommended” way to do it.

I guess try what you are thinking. I think the recommended way is set up the AUX and with the same crossover slopes and balance the outputs of tops and sub then run all the aux sends at 0db (unity gain) with a DCA or group keeping the overall levels of sub and tops the same on changes to the master. This way it all works just like a normal – non aux – set up BUT with the advantage that the accumulated mud from vocal and other open mics with no useful low content physically can’t get to the subs because they are not routed to the subs.
This article explains quite well. https://totalproaudio.stevebunting.com/206/system-design/aux-fed-subs/

But it is what works with what you have that’s important eh.

[Author]

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