Subwoofer causing a tornado in the room
Discussion
I set up our 5.1 system last week, and sat back to watch Dark Knight with the sound cranked up.
Not far into the film, there was a huge gust of wind, so I ran out of the room to close the front door. But it was already closed. I went back into the TV room and sat down, only to be hit by another gust and a slight burning smell.
I then realised it was coming from the subwoofer. I checked round the back of it, and it was pumping out loads of air - Hey presto, interactive TV!
Is that normal? (It's a Monitor Audio BRW10 if that makes any difference)
The burning smell must have been the flux burning off the connectors as it's brand new.
Not far into the film, there was a huge gust of wind, so I ran out of the room to close the front door. But it was already closed. I went back into the TV room and sat down, only to be hit by another gust and a slight burning smell.
I then realised it was coming from the subwoofer. I checked round the back of it, and it was pumping out loads of air - Hey presto, interactive TV!
Is that normal? (It's a Monitor Audio BRW10 if that makes any difference)
The burning smell must have been the flux burning off the connectors as it's brand new.
Sounds like you have the correct pressure loading for your room, just beware that unless your in a detached house your neighbours will be less than impressed with you.
Bass travels a long way.
Have you set your sub x-over to direct? if not do so. and make sure your main speakers are set to small, even if they are floor standers.
and subs need about at least 100 hours to run in.
any help needed let me know as i distribute high end subs as a job.
Bass travels a long way.
Have you set your sub x-over to direct? if not do so. and make sure your main speakers are set to small, even if they are floor standers.
and subs need about at least 100 hours to run in.
any help needed let me know as i distribute high end subs as a job.
FlossyThePig said:
scott.s said:
Sounds like you have the correct pressure loading for your room
Just how do you set the volume of a sub woofer in relation to the rest of the speakers?I hope it's not a case of sod the quality feel the vibration.
1. You may not like the sub at the default volume because of domestic problems so turn it down or turn it up if you can and like lots of bottom end pressure.
2. Room acoustics can cause many problems and the bass will affect the whole system if it's not managed properly.
Most people set there subs to loud to start with as they like the boom factor but after a few months it always gets turned down to a reasonable level, but don't forget the LFE channel is the second most important channel in a multi channel set up. it's got a lots of information going down it as a large part of a action film is not what you can here but what you can feel without sounding bloated and slow.
Set it to where you are most happy and try to get a balance between movies and music. Music is about 40-50% quieter than a action movie.
I really depends on what your trying to do with the sub, i just use my sub for high-end hi-fi so when i switch it off is the only time i know there is a sub in the system.
Scott's got it right.
When you first get a sub it is tempting to get it to go louder than what the film intends.
It is a difficult thing to get right. If you already have big front speakers then I wouldn't set the crossover at anything higher than 80-90Hz.
Otherwise all you are doing is duplicating what the front speakers should be doing adequately themselves and making it muddy.
My front speakers are big, and the sub is huge so I can set it as low as 75Hz.
It basically means the energy is not spent on power just duplicating your front speakers, but the power is used by lowering the frequency range for more 'slam'.
As for feeling a strange wind and getting a smell - I would check what you just had for tea!
Seriously though, are you pointing the back of the sub at your face?
I wouldn't run it at any more than 40% tops until you have used it a bit more and it is run in. Bass speakers move a hell of a lot of air and there are a lot of forces involved on the speaker than hasn't loosened up yet.
When you first get a sub it is tempting to get it to go louder than what the film intends.
It is a difficult thing to get right. If you already have big front speakers then I wouldn't set the crossover at anything higher than 80-90Hz.
Otherwise all you are doing is duplicating what the front speakers should be doing adequately themselves and making it muddy.
My front speakers are big, and the sub is huge so I can set it as low as 75Hz.
It basically means the energy is not spent on power just duplicating your front speakers, but the power is used by lowering the frequency range for more 'slam'.
As for feeling a strange wind and getting a smell - I would check what you just had for tea!
Seriously though, are you pointing the back of the sub at your face?
I wouldn't run it at any more than 40% tops until you have used it a bit more and it is run in. Bass speakers move a hell of a lot of air and there are a lot of forces involved on the speaker than hasn't loosened up yet.
Thanks for the helpful information.
Fortunately I have no adjacent neighbours, but I will politely ask over the road in case they've noticed any "tremors".
scott.s said:
Have you set your sub x-over to direct? if not do so. and make sure your main speakers are set to small, even if they are floor standers.
I'll have to check the x-over as I can't remember off the top of my head (what difference does it make?). The speakers are definitely set to small; I remember doing that.Fortunately I have no adjacent neighbours, but I will politely ask over the road in case they've noticed any "tremors".
jacobyte said:
Thanks for the helpful information.
Fortunately I have no adjacent neighbours, but I will politely ask over the road in case they've noticed any "tremors".
Let the processor handle the cross over and set the sub to direct as this will give the sub more head room ( sound more open). with the crossover it depends on what speakers you have as to what setting.scott.s said:
Have you set your sub x-over to direct? if not do so. and make sure your main speakers are set to small, even if they are floor standers.
I'll have to check the x-over as I can't remember off the top of my head (what difference does it make?). The speakers are definitely set to small; I remember doing that.Fortunately I have no adjacent neighbours, but I will politely ask over the road in case they've noticed any "tremors".
a rough guide would be between 80 and 120hz
Umm, no crossover in mine, or at least nothing that looks like it. It has the following:
Power: Off/Auto/On (set to Auto)
Phase: 0/180 degrees (set to 0 degrees)
Frequency: variable from 40-120 (set to about 70)
Volume: variable (now set to about 40%)
What's "Phase"? The manual said to set it to 0, so that's what I did (although when setting up the amp [Yamaha dspx763] I temporarily set it to 180).
Power: Off/Auto/On (set to Auto)
Phase: 0/180 degrees (set to 0 degrees)
Frequency: variable from 40-120 (set to about 70)
Volume: variable (now set to about 40%)
What's "Phase"? The manual said to set it to 0, so that's what I did (although when setting up the amp [Yamaha dspx763] I temporarily set it to 180).
jacobyte said:
Umm, no crossover in mine, or at least nothing that looks like it. It has the following:
Power: Off/Auto/On (set to Auto)
Phase: 0/180 degrees (set to 0 degrees)
Frequency: variable from 40-120 (set to about 70)
Volume: variable (now set to about 40%)
What's "Phase"? The manual said to set it to 0, so that's what I did (although when setting up the amp [Yamaha dspx763] I temporarily set it to 180).
Frequency I am pretty sure will be the crossover frequency as described.Power: Off/Auto/On (set to Auto)
Phase: 0/180 degrees (set to 0 degrees)
Frequency: variable from 40-120 (set to about 70)
Volume: variable (now set to about 40%)
What's "Phase"? The manual said to set it to 0, so that's what I did (although when setting up the amp [Yamaha dspx763] I temporarily set it to 180).
Phase at 0 will be normal use.
If you change the phase to 180, you are effectively reversing the phase of the soundwave. So when your main speakers go out, it goes in.
Sound is a funny thing whereby if you do this under perfect conditions this would put the speakers 'out of phase' and cancel eachother out so you would hear no bass.
However, in reality the waves bounce around your room. In practice, in most conditions '0' will be fine however, it may be through some freakish chance where you have placed your sub means that the sound bouncing around cancels itself out.
Try one, and then the other. The louder one of the two is the right one.
put the frequency to max (120) - this is effectively removing the crossover, as your amp will certainly be set lower than that.
next, play some music with a decent bassline - one that goes accross a few frequencies. Switch from 0 to 180 degrees, the louder one is correct, as the poster above me said. The reason for the 0/180 degree thing is that some amplifiers invert waveforms during the amp process - so out becomes in etc.
next, play some music with a decent bassline - one that goes accross a few frequencies. Switch from 0 to 180 degrees, the louder one is correct, as the poster above me said. The reason for the 0/180 degree thing is that some amplifiers invert waveforms during the amp process - so out becomes in etc.
Phase can cure 90% of problems in a room if used correctly.
ok here is the easy (very basic) guide to phase.
Phase is the timing between the sub and your main front speakers, get it wrong and you will basically get a collision between the output from your sub and your speakers. it's just like a car crash with mess and confusion.
Most basic subs come with either 0 or 180 degrees with is either sub at the front or sub at the back of the room. SUBS ARE ALWAYS BEST AT THE FRONT, it's because it will be firing off the same plane as the front speakers and timing wont be an issue, so 0 degrees is the right setting.
so if your subs at the back you need to invert the phase to 180 to avoid that car crash.
a lot of people have them at the side of the room with would either be 90 or 270 if your sub has that option. if your subs at the side and you don't then listen between 0 and 180 to which sounds better.
ok here is the easy (very basic) guide to phase.
Phase is the timing between the sub and your main front speakers, get it wrong and you will basically get a collision between the output from your sub and your speakers. it's just like a car crash with mess and confusion.
Most basic subs come with either 0 or 180 degrees with is either sub at the front or sub at the back of the room. SUBS ARE ALWAYS BEST AT THE FRONT, it's because it will be firing off the same plane as the front speakers and timing wont be an issue, so 0 degrees is the right setting.
so if your subs at the back you need to invert the phase to 180 to avoid that car crash.
a lot of people have them at the side of the room with would either be 90 or 270 if your sub has that option. if your subs at the side and you don't then listen between 0 and 180 to which sounds better.
After having my sub at the front for years I did some experimentation over a weekend and found in my room anyway having the sub at the side was best.
You have to remember that the sound waves for the sub are something like 4-6 metres long. In the majority of lounges you are not even getting the full wave direct to you, most of the sound - or more accurately woompf - is coming from the walls and other objects.
As the wave is so long, you will find that there are lots of dead spots where the sound of the sub is minimal as the energy of the wave has bounced of something and met itself as a reflection and cancelled itself out. This is where the phase is useful so you can effectively tweak where the dead spots are and are not.
Whereas phase is a tweak, moving your sub will have much more effect. Moving it out of a corner or facing into the centre of the room can make the difference between a wooly woompf and a slam.
You have to remember that the sound waves for the sub are something like 4-6 metres long. In the majority of lounges you are not even getting the full wave direct to you, most of the sound - or more accurately woompf - is coming from the walls and other objects.
As the wave is so long, you will find that there are lots of dead spots where the sound of the sub is minimal as the energy of the wave has bounced of something and met itself as a reflection and cancelled itself out. This is where the phase is useful so you can effectively tweak where the dead spots are and are not.
Whereas phase is a tweak, moving your sub will have much more effect. Moving it out of a corner or facing into the centre of the room can make the difference between a wooly woompf and a slam.
Oh dear, this is kind of fun. I feel I'm going to have another expensive interest very shortly (a better HiFi is next on the list, for another room).
Is the sub OK like this...? I can't rotate the speakers as it's only Word Drawing, but the arrows show the direction of how the speakers are toed in slightly.
Is the sub OK like this...? I can't rotate the speakers as it's only Word Drawing, but the arrows show the direction of how the speakers are toed in slightly.
Re. sub placement, I'd heavily reccomend 1/2 way along a wall - the wall between the 2 hardest walls in the room. Keep it as close to the wall as possible, to avoid causing total cancellation of 1 frequency. If thats not compatible with domestic bliss, put it where she lets you, as long as it is next to a wall!
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