Rational Acoustics



Dr. J
February 7th, 2015, 02:55 AM
Hi fellas, I have never attempted the Aux Fed Sub option but it seems to be popular. Would anyone care to comment on their experience with this configuration?

I have heard a system where this was done and it had some qualities I liked but others I did not like. It really seemed muddy and muffled. Kinda the opposite of what I thought I would hear. I asked the guy what method he used to set it up and he said his ear.

I know it can be done using Smaart but you obviously have to be smart about it... I am sure Smaart views the aux sub as contamination correct? Does the acoustic crossover become a "floating" crossover point where it can literally be in time and then out of time? This guy wouldn't leave the sub fader alone...

Thoughts?

gluis
February 24th, 2015, 11:21 AM
Hi fellas, I have never attempted the Aux Fed Sub option but it seems to be popular. Would anyone care to comment on their experience with this configuration?

I have heard a system where this was done and it had some qualities I liked but others I did not like. It really seemed muddy and muffled. Kinda the opposite of what I thought I would hear. I asked the guy what method he used to set it up and he said his ear.

I know it can be done using Smaart but you obviously have to be smart about it... I am sure Smaart views the aux sub as contamination correct? Does the acoustic crossover become a "floating" crossover point where it can literally be in time and then out of time? This guy wouldn't leave the sub fader alone...

Thoughts?

Hi Dr. J

What I do is to tune the system with the sub destined aux at nominal level (let's say, 0dB of gain on aux send in the channel I'm using for Pink Noise). Then when I'm mixing, every channel I need Sub in it I raise the aux exactly to nominal, to make sure the relationship between Subs and Full range is maintained.

I do it only if I'm mixing, or if it is a rider requirement, because most engineers that ask for subs on an aux don't really know what they are doing and end up doing more harm than good. Either they mess up your carefully obtained balance, or they force your full range speakers on the LF range as they don't use enough sub level.

By the way, in most digital consoles you can convert an aux to a group (which is nothing more than an aux with sends fixed at nominal). This way is easier, you just turn on the sub on the pertinent channels.

I would also like to know what others do, so I'll be checking comments :-)

GS

Dr. J
February 24th, 2015, 07:36 PM
Thanks for the reply Gluis... Sounds like a nice way to do it. The January issue of FOH - has an article on "Feeding the Subs".

Thanks again!

gluis
February 26th, 2015, 01:23 PM
No problem. Glad I can add my two cents to the discussion :-)

GS

Harry Brill Jr.
May 1st, 2015, 01:18 AM
I do it like you.

If the desk has a sep assignable mono bus, I use that.

The reason I drive the subs separately is to keep things out of them that don't belong there.


Hi Dr. J

What I do is to tune the system with the sub destined aux at nominal level (let's say, 0dB of gain on aux send in the channel I'm using for Pink Noise). Then when I'm mixing, every channel I need Sub in it I raise the aux exactly to nominal, to make sure the relationship between Subs and Full range is maintained.

I do it only if I'm mixing, or if it is a rider requirement, because most engineers that ask for subs on an aux don't really know what they are doing and end up doing more harm than good. Either they mess up your carefully obtained balance, or they force your full range speakers on the LF range as they don't use enough sub level.

By the way, in most digital consoles you can convert an aux to a group (which is nothing more than an aux with sends fixed at nominal). This way is easier, you just turn on the sub on the pertinent channels.

I would also like to know what others do, so I'll be checking comments :-)

GS