ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 ... 6 7 [8] 9 10 11   Go Down

Author Topic: Why not Aux Controlled Subs?  (Read 7532 times)

Keith Broughton

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 572
Re: Why not Aux Controlled Subs?
« Reply #70 on: January 18, 2014, 02:57:36 pm »

It's because we often run subs hotter than tops for live music, I think. For example, if I choose to HPF a vocal at 100 Hz on a full range system crossed @ 100 Hz with the subs 6db hotter than the tops, some of that <=100 Hz will be going through the subs at +6 compared to the >=100hz going through the tops. In response I take my HPF filter and move it up (or on an LS9 - up a lot), losing some of that 99-125 from the tops I was perhaps looking for. On a group/aux-fed system I can let a channel go as low as the tops will go, without encountering    +xxdB subs because I simply don't assign it. Despite barely hanging on to the science at hand, I'm still comfortable based on this thread and my experience with saying that when I work on professionally tuned systems I get more consistent behavior in the crossover area by using group-fed subs as opposed to aux-fed subs with varying levels.
I think this is the best argument for aux fed subs.
Logged

Greg Cameron

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 555
    • Cameron Pro Audio
Re: Why not Aux Controlled Subs?
« Reply #71 on: January 18, 2014, 03:58:38 pm »

Despite barely hanging on to the science at hand, I'm still comfortable based on this thread and my experience with saying that when I work on professionally tuned systems I get more consistent behavior in the crossover area by using group-fed subs as opposed to aux-fed subs with varying levels.

I think I can safely say that most of us folks that use subs on an actual aux send run those channel sends at detent or "unity" for the most part. When doing that, there's no difference in crossover point between using a group bus, aux, or non-aux/bus feed "old school" setup. So the argument is mostly moot. The only time I find myself not doing that on a particular channel is most often when I feel a need to dial down the send level. Usually that's on a bass guitar channel, a floor tom, or a keyboard where the tuning is such that the sub level is overwhelming relative to the tops and a low shelf isn't the call. There's nothing wrong with doing that IMHO. And on rare occasion, I might crank a sub send up for a special effect. Cool to have that control when you want it. Bummer not to if you don't. 8)
Logged
"Procrastinators of the world - contemplate uniting!"

Cameron Pro Audio

Mark McFarlane

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1634
  • Middle East
    • Arkose Records
Re: Why not Aux Controlled Subs?
« Reply #72 on: January 19, 2014, 02:37:07 am »

I think I can safely say that most of us folks that use subs on an actual aux send run those channel sends at detent or "unity" for the most part. When doing that, there's no difference in crossover point between using a group bus, aux, or non-aux/bus feed "old school" setup...

Greg, I think the concern of the shifting acoustic crossover point is how the sub's aux master send is set relative to the main fader, and how their relative levels may change during the show, not the individual channel sends.

I, like you, often find myself turning down aux sends on bass, sometimes kick or toms depending on how they are tuned and the room,...  I guess I am from the 'use it s an effect' camp for rock shows.
Logged
Mark McFarlane
ARKOSERECORDS
Turn down what's too loud.

Greg Cameron

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 555
    • Cameron Pro Audio
Re: Why not Aux Controlled Subs?
« Reply #73 on: January 19, 2014, 03:17:52 am »

Greg, I think the concern of the shifting acoustic crossover point is how the sub's aux master send is set relative to the main fader, and how their relative levels may change during the show, not the individual channel sends.

If you change a sub send for an individual channel, you are shifting the acoustic x-over point for that channel as gain is gain whether you adjust it from a channel aux or an aux master. Granted you're not changing the alignment of the whole system. But a relative shift is occurring. That said, it really doesn't matter if you're getting the sound you desire..
Logged
"Procrastinators of the world - contemplate uniting!"

Cameron Pro Audio

Mark McFarlane

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1634
  • Middle East
    • Arkose Records
Re: Why not Aux Controlled Subs?
« Reply #74 on: January 19, 2014, 03:25:11 am »

If you change a sub send for an individual channel, you are shifting the acoustic x-over point for that channel as gain is gain whether you adjust it from a channel aux or an aux master. Granted you're not changing the alignment of the whole system. But a relative shift is occurring. That said, it really doesn't matter if you're getting the sound you desire..

Agreed gain is gain, agreed....
Logged
Mark McFarlane
ARKOSERECORDS
Turn down what's too loud.

Mike Karseboom

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 64
Re: Why not Aux Controlled Subs?
« Reply #75 on: January 20, 2014, 10:37:58 am »

A slightly different slant on this that messed me up a couple of times is that the crossover frequency you choose might need to be lower with group/aux fed subs. 


In the "non-aux" situation where all input channels go the the system processor for separation to subs and tops I was typically setting that crossover frequency to 100Hz.  With 12" powered top (K12) over a single 18" sub (srx718) per side indoors this was giving good results.


When I started putting just kick, floor tom, bass, and (when present) keys into the aux sub feed I created somewhat of a sonic hole from 100Hz down to say 80Hz or so.  Many instruments and even vocals have some content in that frequency range.  So while cleaner sounding way down in the lower octaves the overall system sound lost some "solidness" or "authority" for lack of a better description. 

The 12" mains were being high passed  at 100Hz so they were not producing these frequencies and the subs never got a lot of that content sent to them in the first place.  This was really obvious is someone cut to an acoustic guitar and vocal solo.  It sounded pretty thin.

After moving the crossover point down to 85Hz I think the system sounds fuller and more balanced.  As always YMMV.
Logged
--Mike
"If your not confused, you don't know what is going on"

Live Sound for the Mt. Shasta area
http://www.shastalivesound.com

Greg Cameron

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 555
    • Cameron Pro Audio
Re: Why not Aux Controlled Subs?
« Reply #76 on: January 20, 2014, 12:39:05 pm »

A slightly different slant on this that messed me up a couple of times is that the crossover frequency you choose might need to be lower with group/aux fed subs. 

Agreed. I'm high passing my tops at 60Hz.
Logged
"Procrastinators of the world - contemplate uniting!"

Cameron Pro Audio

Sndguy (Joel Ashcraft)

  • Classic LAB
  • Newbie
  • *
  • Offline Offline
  • Posts: 34
    • Midnight Blue online
Re: Why not Aux Controlled Subs?
« Reply #77 on: January 20, 2014, 02:32:08 pm »

Aux fed subs all the way. Occasionally with bass guitars where the low notes have a lot more energy in the subs than wanted, I'll dial down the sub send from detent. Does it shift the relative acoustic crossover point down? Sure. But who cares? If it sounds good, it is good.


+1

This has always been my philosophy.
Logged

Malcolm Macgregor

  • Newbie
  • *
  • Offline Offline
  • Posts: 17
Re: Why not Aux Controlled Subs?
« Reply #78 on: January 20, 2014, 02:32:39 pm »

Agreed. I'm high passing my tops at 60Hz.

Same here, L'Ac 60Hz and D&B 70Hz. Works just as well on other brands to except smaller single top setups, but that's a whole other story :)
Logged

Greg Cameron

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 555
    • Cameron Pro Audio
Re: Why not Aux Controlled Subs?
« Reply #79 on: January 20, 2014, 02:35:07 pm »

Same here, L'Ac 60Hz and D&B 70Hz. Works just as well on other brands to except smaller single top setups, but that's a whole other story :)

Yeah, if I'm working on rig with weaker LF drivers in the tops, I'll start sweeping the high pass up until the they're not sounding as strained. Then bring the sub low pass up to compensate.
Logged
"Procrastinators of the world - contemplate uniting!"

Cameron Pro Audio
Pages: 1 ... 6 7 [8] 9 10 11   Go Up
 


Page created in 0.13 seconds with 23 queries.