seeking advice from experienced mobile DJs and sound engineers
Hey guys, I just wanted to ask a couple of questions. When I set about building my first “beginner’s P.A.” I didn’t really do much talking to anyone. I just started reading about products and forum posts to find out what things I would need. When I say “beginner” I of course mean entry level, but despite that, I found my research leading may to pay much more on certain things that I was expecting.
Question 1: I read that all this powered equipment needs these super large gauge extension cords to handle the wattage or voltage. Whatever. So the first thing I order is a bunch of these expensive, heavy as heck extension cords and then I get my powered subs and speakers, only to find that they all have little pencil thin power cords.
So what gives? Did I just make a fool out of myself and my wallet, buying these for no reason. Or are there some
large gauge power cords I don’t know about and I need to be getting those to? (this only matters now because I still need more cords)
Question 2: I had an 18" powered subwoofer, rated at about 800 watts I think. I used it in a small wedding and the bass was great, with the volume barely even turned up. Then I get a deal to get a second matching sub and when I run two of them, there’s way less bass than one. So again I’m like “what the heck?”
I know I have them wired right and I basically put one next to the left speaker and one next to the right speaker and it seems like I have to turn them way up, just to even tell they are on. Yet when I use just one, it doesn’t have to be turned up much. This is crazy.
Any suggestions would be appreciated. Please don’t bash me on product selection or anything like that. Again I did say “beginner” I’m poor. I know that’s a crime. lol
I tried a couple of different wiring methods but I will look into what you said.
Since all of my speakers are powered and I have a very small setup, I wasn’t
sure that would apply to me.
I have my Denon Controller using 1/4" line outs into the L/R inputs of one powered sub. I output from the sub’s L/R with XLR cables into the second sub. The second sub L XLR out goes into my left powered speaker and the second sub R XLR out goes into my right powered speakers. That’s it.
Then I do all the gain staging procedures.
I have always spread the two subs out, next to the two speakers. When I only had one sub, I put it in the middle and my bass has never been better than that time using one.
These subs don’t have any kind of phase inverting switch or anything like that. (cheapness) All that have is the volume level and some sort of crossover or filter, that says, 40hz to 120hz.
Maybe that information will help.
Also, nobody has commented yet if I am wasting money on heavy gauge extension cords.
The power leads (the short cord from the equipment to the wall) are sized based on the current draw that the cord will be supporting. These cords tend to be short (3-10ft). Because the cable is short, the total resistance of that cable will be (relatively) low. The issue limiting power cords tends to be the heating load that the cable can safely carry.
Keep in mind that an extension cord has a “to” and a “from” path for the current - so the length of the conductors is twice the length of the cable.
I use 40ft 12ga extension cords with SOOW rubber jackets. They are heavy, expensive, and will last a lifetime - unless someone steals them.
This is a classic phase issue. If possible, reverse the conductors going to one of the subwoofers and retest.
I would try sending the left channel to one sub and it’s monitor and the right channel to the other sub and it’s monitor. ALso please post the make and model of your subs, please.
This has a reasonable write up with some pictures.
If you have an amplifier that uses “binding posts” you can wire the subwoofers one way, and then switch one of them. “Banana plug” connectors are handy.
I have done that method with very little difference. The manufacturer of this sub actually tells you to use both L/R the way I have it to increase performance. And of course when I ran a single sub, I ran L/R instead of just one channel.
Definitely sounding like one is out of phase. Have you tried setting up your system outside? Another possibility is standing room nodes, how big was the space you set these up in?
I’ve never tried it outside. The room I was in this past weekend was a small hotel meeting room. There were enough long tables and chairs in there to seat maybe 60 people with standing room for many more around the boundaries. (maybe 100) All of that was removed.
My gig, a few weeks prior was in a room maybe 20 ft wide and 40 ft long, with VERY high ceilings (probably 30 ft) possibly a bit much for my minimal gear.
Now since I am using all powered gear, I have no wiring to switch to change phase to check for a problem. All I have is my signal input cables. I guess I could open both subs and see if they are wired the same internally?
Hopefully they are not soldered connections or I will have to outsource help to fix that.
Are both your TRS to XLR cables that you’re using from the same company? If you have a voltage meter you can easily check the phase of the cables. Also, please post the make and model of your subs.
I use 2 TRS to TRS and 4 XLR to XLR. They are all the from the same company and have only been used a few times. I don’t have the voltage meter, but I will get one.
Now I will post my subs and hold my head down in shame for a scolding.
Seismic Audio - Aftershock 18" x 2
Crazy thing about it is that my audiences think it sounds great, but my brother and I can tell what’s lacking. Then again I have friends who can’t tell when an mp3 sounds bad.
