DJ’ing school dance, given me permission to rent whatever,I need need help with setup
Howdy! This is my first Post on this forum, so forgive me if my posting etiquette is not quite up to par!
I’m DJing a school dance on the 29th of October In the school’s gymnasium. I did the same gig last year and they loved me enough to ask for me back! Just as last year, they gave me full permission to rent whatever I need to make things great.
I’m renting from Long and Mquade Canada so expense won’t be too much of a factor.
This list has everything I’ve decided to rent as of now.
The dance should have anywhere from 600-800 people. (Rough guesstimate)
Assuming that the forums approve of this equipment, I’m torn between these two setups. (Picture in the attached file include the two setups)
Are either of these two setups good for the equipment I’m getting? Is the equipment I’m getting enough for an event like this? If not, what should I add/Change?
The two small tops can be used as monitors for the booth (point them at the DJ) or left out. There is NO benefit for mixing top types in this kind of setup, and only potential issues.
The mixer is OK, but is certainly not a DJ style mixer. What is the source of the music?
The subs need to be put next to the wall. They do not need to be “centered”…so whatever works best for logistics. In general 1/3 of the distance along a wall from the corner should allow room for the DJ booth to also be pushed against the wall.
For best overall coverage: This needs the wall with the DJ booth to be about 75ft long. The tops should split the wall with the booth. About 20-25ft between the stands is best. The tops can be placed next to the wall. This will give some stand off distance to the dance floor, allow for better integration of the sound field, and avoid having people in the “zone of death” immediately in front of a speaker.
Keep the horn 1-2ft over the heads of the audience on the dance floor. Given a 1.5ft raised dance floor, and a 6ft person - place the horns 9-ish ft from the floor. If there is significant slap-back from the far wall, turn the speakers toward the center of the room by about 30 degrees.
Unfortunately, while I did say i’m free to rent whatever, I can only rent from long and Mquade (Or else the pricing would probably get a little out of hand). I’ll keep this in mind for future gigs though, thank you!
Lighting is also included towards the bottom of the google doc. Would you say that setup is alright? (The lighting board gives full control over a total of 8 LED lights)
The two smaller speakers are to balance the low frequency subs with the high frequency. I’m hoping that phasing issues and the like won’t be a problem. I’ve received some advice about the subs being centred vs panned (Some of the ups and downs of doing both) from another forum, and (since putting them together will give me 3db more head room) I think it’s an alright sacrifice in exchange for the ally of power (Although once i can set everything up for sound check, I might change my mind). Regardless, they Will be close to the back wall, so hopefully that helps! Unfortunately I won’t be able to get a DJ booth, but i will definitely get the tops as close to the walls as possible! Thank you for the Speaker hight tip, Just what I was looking for! Slap back from the back wall shouldn’t be too bad, but if it is, i’ll be sure to angle them in a more as you suggested! Thank you a ton for the help!
No, the small speakers will not balance anything. They will have a different response and pattern than the larger tops and will need independent processing (31 band & crossover) to even have a shot at integrating into the overall sound field.
The “best case” is for the smaller tops to be 3+dB lower than the tops across their passband. This will have no discernible effect on the final sound in the middle of the dance floor.
The “worse case” is a muddy mess in the mid bass ranges.
This is a time when whatever intuition you think you have about sound is wrong. Mixing different types cabinets that are producing the same passband is complication you do not need for gains you will not actually get. Leave them out, or point them at the DJ as monitors.
Setting up the system “touching” the wall will create some “stand off distance” between the cabinets and the audience. This distance allows the sound field produced by the different cabinets to integrate before reaching the audience. That integration is likely the “balance” that you think you are looking for.
In my placement advice, the subs will still be touching (+3dB for coupling). In my advice the subs will also be coupled to the wall, and that will move them from half-space to quarter space (+6dB).
You NEVER want to place subs 1/4 wavelength from a boundary, the reflection will be 1/2 wavelength out of phase and that creates a -24dB notch filter at the critical frequency. Using 40Hz (7.5ft 1/4 wavelength) and 100Hz (2.5ft 1/4 Wavelength) as guides, subs should never be placed between 2.5ft and 8ft from a wall or corner. More than 8ft from the boundary and you lose the +6dB per wall for boundary reinforcement. Less than 2.5ft from the wall is best.
For reference a +6dB gain can also be achieved by doubling the cabinet count. Boundary loading is HUGE when it comes to subs.
Having the subs “off center” is MUCH less of a big deal than you would think. Below 100Hz, it is hard for people to “localize” the source of a sound - low frequencies are effectively omnidirectional. The gains in output happen EVERYWHERE in the room. So, while the cabinets might be 8ft (or more) further away from the dance floor, the overall bass on the dancefloor will be louder and more even.
Alternatively, put the subs next to the wall in the center, and make the DJ booth (or table) “off center.” Symmetry might be pleasing to the eye, but it tends to mess up sound.
EDIT:
Just to be clear, the cabinet placement choices that I am describing are EXACTLY how I would approach putting my gear into that same space. I am not offering advice that is anything other than what I would do if it were my reputation on the line.
Thank you so much for all the advice you’ve been suggesting, I’ve been learning alot.
Three questions:
1: If I decide to put the subs under the mains towards the side of the stage, close to the walls, would that give the wall boundary re-enforcement you’re talking about?
2: If I put the subs in front of the DJ booth, and have a panel behind them,would that count as a wall? How thick would that panel have to be to work? (If it works at all?)
3: If I have the option to, would it be better to rent out 4 1000 watt subs and group them together towards the center?
thanks in advance!
Yes. Provided the radiating plane of the cabinet is less than 2.5ft from the boundary, the reinforcement will happen. In practical terms, this means that the cabinets should likely be FACING the wall.
As a starting point, I put direct radiators 1/2 the cone size from the wall - so a 15" sub has a 7.5" gap from the wall, and an 18" sub would have a 9" gap from the wall. Add another 6" every time the number of cabinets in the pile doubles.
If you have more than eight cabinets…you should already know what you need to do.
A boundary must be one wavelength in all directions, and should be “rigid” (anything “interior wall” or better is OK). At 40Hz, a wavelength is 28ft. So, provided the panel is 28ft in all directions, it will still work. In practical terms, you really want a solid wall.
Keep the doors on the wall with the sub closed whenever possible. A single open door will make a small enough difference to ignore. Four sets of double doors that are full open (e.g. like a typical gym) will have a substantially noticable effect.
Sound level is not measured in watts. Sound is measured in SPL in units of dB, and the response will vary across the passband. Without an SPL chart, or at least a “@1w@1m” sensitivity rating, it is difficult (or impossible) to compare the performance of two subs based only on peak power handling.
Given what you are doing, either set of subs would be OK. Pick based on cost, or pack space, or weight.
You will only be able to do the best you can with the sound being its in an open gym. If you have the time try different set ups to hear what sounds the best.
