Yet another newbie, sorry guys

Anything not covered elsewhere.
Message
Author
LioninSpace
Posts: 27
Joined: Tue Aug 16, 2022 2:44 am

Yet another newbie, sorry guys

#1 Post by LioninSpace »

I know it sucks: Every new guy (noob) gets in and starts a new topic instead of researching and find the answers you guys have been given to countless others before him...

Truth is, I tried. I just didn't seem to be able to find the answers to my questions elsewhere so here it goes: (background)

I am renting a house with an extention that used to be a dance school. Since two years I am working on making it my little private disco/workout room (on a budget of course). It has not much in it so that I can quickly make it a party room. It has about 800 square feet for the dance floor and another few sqft where one steps out of the house and stands on what I use as my DJ booth, an elevated space, overlooking the room with two sets of stairs going down either side into the room.

The room layout is somewhat complicated and I am going to try to create a drawing to help, but that will take some time.

The room has four corners but none could be used to place the subs. One is right next to the outside entry to the room (folks don't have to go through the house), one has windows and curtains instead of walls and the other two a mirror wall and in not enough distances behind it a neighbor's multioccupancy house. Those neighbours, I should not upset by bouncing my subs off that wall. So I would need to use direct radiation into the room from my DJ booth with an elevation that I would guess as 4 ft.

So far, I own two 15" BR subs which I used stacked, but they don't do much to fill the room, let alone produce anything that you can feel. It was a used purchease and a bad choice.

Question: Is an indoor room of that size (large for a sitting/living room, but small for a club, holds about 50-65 guests) better served with some quality BR speakers, or would it benefit from something I would build?


I have read quite a bit about the subs build to plans from this site and others. I am however getting the feeling that this would be a complete overkill for my room. It`s a fixed installation and I don't need to think much about reach/throw but rather reflextions and cancellations. Especially since I can't use any corner. Not even a wall really, except if I lift the speakers up to the celing, but that one isn't straight like the floor but is constructed as "hills and valleys" to limit reflextions. Not ideal.

Any thoughts?

Thanks guys!

User avatar
Bill Fitzmaurice
Site Admin
Posts: 28619
Joined: Tue May 02, 2006 5:59 pm

Re: Yet another newbie, sorry guys

#2 Post by Bill Fitzmaurice »

No bass reflex subs or mains can compete with horn loaded. As for placement of subs that's a matter of ingenuity. When you approach any project leading off with the words "I can't" it's doomed to failure. As for "Those neighbours, I should not upset by bouncing my subs off that wall " the output of any and all subwoofers is omni-directional.

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Yet another newbie, sorry guys

#3 Post by Seth »

LioninSpace wrote: Thu Aug 25, 2022 8:21 am 15" BR subs
Welcome to the forum. Happy to have you here. I'm Seth. What can I call you?

Do you have a link to the subs you're using?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Grant Bunter
Posts: 6915
Joined: Mon Nov 28, 2011 11:12 am
Location: Ilfracombe Queensland Australia
Contact:

Re: Yet another newbie, sorry guys

#4 Post by Grant Bunter »

G'day, and welcome to the forum :)

Even if you get nothing else from your time here, you should learn this:
viewtopic.php?f=10&t=398
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

LioninSpace
Posts: 27
Joined: Tue Aug 16, 2022 2:44 am

Re: Yet another newbie, sorry guys

#5 Post by LioninSpace »

Thanks for the quick responses everyone.

Bill: I know that BR can't compete. The question is rather if the room is big enough for horns to fill without over-powering it. Especially when their curves do smooth as soon as you start to stack them which gives them even more power.
Am I wrong to think that horns do give low frequency a certain amount of direction? Isn't that what creates the throw? After all, you don't try to move massive amounts of air with the relative small membrane movement (direct radiators), you do it in a tight space to improve efficiancy and than 'point' it into a megaphone that is wrapped around like a snail with a big opening at the end.

Seth: here a link to those BRs. They are what you would call cheap and cheerful even if they really do lack the last bit :) Renting this place is putting me in a tight spot financially, so there are limits to what I can do.
https://www.steinigke.de/de/mpn11037711 ... -800w.html

They are run with this amp:
https://www.gear4music.de/de/PA-DJ-and- ... YAQAvD_BwE

Sorry for the German discriptions, but the main data should be readable.

Grant: Yes I have read it. And that is why I made the comments in my original posting. Those positions are not easy accessable in this room and have considerable draw-backs for the use of the room. There is a lot of glass (windows/doors with curtains) and a massive mirror in this room. Not ideal if you want to bounce something of that. I can still experiment some more but I see limitations (no Bill, I am not trying to approach it with a can't be done attitude. I wouldn't trouble you guys if I were). I am hoping that by using horns, I might be able to produce the result I want from a speaker placing position that is most suitable for the situation even when it isn't ideal for a sound-engineer. I just try to do due diligence in accessing the potential outcome before I start the project. Sure, if I would place those horns against a wall, they will become omni-directional as I am using the reflexition of the wall. The question is, what can I do if that is not a vaild option?

And with it being an indoor room, I need to try to think about the reflextions to not end up creating phase shifts killing the sound at the spot were its most needed, the dance floor. No good if the walls are shaking and the neighbours upset while the crowd is not entertained.

Oh, and it is André btw :)

Thanks for reading and input:)

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Yet another newbie, sorry guys

#6 Post by Seth »

André,

With what you currently have, you should be able to bother the neighbors way down the street. The lack of perceived output is more than likely due to room acoustics, cab placement, and to a lesser degree EQ.

In the space you're describing you may find that you get better results if you split the subs into multiple locations. I'd first start with them in opposite corners, even if it's not a location that they're able to remain permanently. Test it, then move one to another location along one of the walls. In each test location, point the sub in one direction, test, then turn it 90° and test, then turn it 90° and test, then turn it 90° and test. When placed in a corner, aim the cab into the corner. Then flip it around. Note any differences. When listening to each configuration, play tracks with differing low end content, the same songs for every configuration and in the same order, walk around the room, listen for how even the sound is throughout the space. Take written notes. Certain songs may have nulls in certain places with certain configurations. Obviously, the goal is to identify which placement configuration provides the most even response throughout the room. Be prepared to test 40 or more configurations. Your written notes will be your best friend, write down every detail you notice. Eliminate the obvious losers, either by sound or by the test position not being realistic long term. But, do test non realistic locations. The more information you gain, the better.

- It wont matter to your neighbors if you aim one or both of the subs into "that" corner or not. Once the correct cabinet placement is found, it will make no difference to your neighbor whether the cab is in that corner or not. They're gonna hear it if you're playing it loud enough.
- Horn loaded subs, in and of themselves, have no more directionality than a BR sub. It's the frequency of sound that is omni directional, based on the width of cab or driver that it's emanating from that dictates directionality. A sub cab would have to be unreasonably wide to produce any directionality, but it can be achieved with a large group of them used together.


Once you figure out which cab placements produce the best balance throughout the room in positions that also work well, choose one. It's time to move on to EQ. Do you have any means of EQing your system?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

User avatar
Bill Fitzmaurice
Site Admin
Posts: 28619
Joined: Tue May 02, 2006 5:59 pm

Re: Yet another newbie, sorry guys

#7 Post by Bill Fitzmaurice »

LioninSpace wrote: Fri Aug 26, 2022 4:46 am Am I wrong to think that horns do give low frequency a certain amount of direction? Isn't that what creates the throw?
It is not. This is: viewtopic.php?f=10&p=289663#p289663

As for 'throw', all point source speakers have the same throw, in that the SPL drops by 6dB with each doubling of distance. The exception is a line array, which drops at 3dB per doubling of distance. Since a line array must be at least three wavelengths high to realize this for all practical purposes there's no such thing as a subwoofer line array.

Horns, and for that matter all speakers, are omni-directional below where their radiating planes are less than one wavelength in dimension. A direct radiator radiating plane is the baffle, a horn radiating plane is the mouth. One wavelength at 80Hz is 4.3 meters.
I am hoping that by using horns, I might be able to produce the result I want from a speaker placing position that is most suitable for the situation even when it isn't ideal for a sound-engineer.
Poor placement will have the same result no matter what speaker is used. The only way to successfully address poor low frequency room response is by using as many subs as possible, spread about the room.

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Yet another newbie, sorry guys

#8 Post by Seth »

BTW, there's no shame in budget subs. I have a 12" BR that cost $80 new. Powered with about 100w, it serves the purpose it's intended for very well. I also have a pair of Behringer 18's that I picked up for $150 each used, they also work well for their intended use. They just take a lot of power compared to horn loaded subs, to get similar output.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

User avatar
Seth
Posts: 2731
Joined: Thu Sep 10, 2009 8:06 pm
Location: Sacramento, California, USA
Contact:

Re: Yet another newbie, sorry guys

#9 Post by Seth »

It may also be worth verifying that the cabs are wired in phase. Play one, then plug the other in. If it gets louder, you're all good. If it gets quieter, they're wired out of phase. Pull the driver or jack plate on one and swap the wires around.
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

LioninSpace
Posts: 27
Joined: Tue Aug 16, 2022 2:44 am

Re: Yet another newbie, sorry guys

#10 Post by LioninSpace »

Hi Guys,

thanks for all the input guys.

Special thanks to Seth. Lots of info and good, helpful suggestions man. Great! That will take me a little while to do and report back with the results, especially as it is most likely best done with a friend running the DJ controller and another changing the placements in 90° steps while I stand in the middle to listen to the changes. That way, we could go forth and back and get a decent impression. Doing it by myself will be rough and won't allow me to really compare except for the most obvious changes.

What I already know: I have tried having them in the two corners opposing the DJ booth and also directly underneath the booth. In both cases, there was several meters distance between them and I didn't hear much of them at all. That's why after some reading (on here and elsewhere) I stacked them. An improvement, but still very little to notice. In each placement, I only had them facing the room as direct radiatiors. It didn't occur to me then to have them facing the corner/wall. There is a lot more I need to try out.

As to EQ, I have an Behringer FBQ6200HD (https://www.thomann.de/de/behringer_fbq6200hd.htm) off which I use the sub-out to cut off all higher frequencies. Once there is a noticable input from those subs to the sound, I want to ring out the room to get the best out of the over-all system.

@Bill:
"The only way to successfully address poor low frequency room response is by using as many subs as possible, spread about the room."
Really? I thought that would create a lot of summation/chancellation-effects at different spots throughout the room and leave me with chaos created by all the reflections from the walls, dampening from the curtains etc.

@Seth again: I paid 300€ for both subs and the amp. Not too terrible, but a painful loss when it comes to the result so far.
I am using the cables the dude sold me with those items. It hasn't occured to me yet that he might have messed those selfmade cables up and put them out of phase. That would explain a lot as he had demostrated them using other (shorter) cables. They were pretty loud but that was in a tiny cellar with low celing. They were also overdriven and sounded messy but I thought they would create enough power in my room even when I don't crank them up to 11, so they should sound alright in the end. And hey, maybe with your help they will. Not sure if that will stop me from building something better in time as I don't feel they will produce something that I can feel (rather than only hear).

As said above, I do have some homework to do :) At least thanks to you guys, I know where to start.

Happy to hear more input and will be back with more info as soon as I have it.

Sending love from Germany,
André

User avatar
Bill Fitzmaurice
Site Admin
Posts: 28619
Joined: Tue May 02, 2006 5:59 pm

Re: Yet another newbie, sorry guys

#11 Post by Bill Fitzmaurice »

LioninSpace wrote: Tue Aug 30, 2022 9:30 am @Bill:
"The only way to successfully address poor low frequency room response is by using as many subs as possible, spread about the room."
Really? I thought that would create a lot of summation/chancellation-effects at different spots throughout the room and leave me with chaos created by all the reflections from the walls, dampening from the curtains etc
Every placement and every listening position will have its own set of cancellations. Move the speaker or move the listening position and the frequencies of those cancellations will move as well. The only cure is to use as many subs as it takes so that whatever cancellations that occur in any given listening position from any given sub is countered by a different sub.

Grant Bunter
Posts: 6915
Joined: Mon Nov 28, 2011 11:12 am
Location: Ilfracombe Queensland Australia
Contact:

Re: Yet another newbie, sorry guys

#12 Post by Grant Bunter »

Andre,
Would you mind telling us what your settings are on the Behringer unit please?
All of them.
Like sub output in Hz.
Is the sub out button on?
Have you used any of the high cut (which is really a low pass) or low cut (which is really a high pass) buttons? If yes, what are they set to?
Is the limiter on?

It's not necessarily cables which can be wired up to be out of phase, speaker cabs can be as well...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

User avatar
Bill Fitzmaurice
Site Admin
Posts: 28619
Joined: Tue May 02, 2006 5:59 pm

Re: Yet another newbie, sorry guys

#13 Post by Bill Fitzmaurice »

Test polarity by running a tone through just one sub, then turn up the second sub. If the level goes up you're good, if it goes down you're not.

LioninSpace
Posts: 27
Joined: Tue Aug 16, 2022 2:44 am

Re: Yet another newbie, sorry guys

#14 Post by LioninSpace »

Hey guys!

Thanks for the continued input.

@Grant: I will take a picture of the unit fired up and will write down what isn't obvious to see when I am back from work.

@Bill:
Every placement and every listening position will have its own set of cancellations. Move the speaker or move the listening position and the frequencies of those cancellations will move as well. The only cure is to use as many subs as it takes so that whatever cancellations that occur in any given listening position from any given sub is countered by a different sub.
As long as I can gain some influence over where the sound is adding and where it is substracting, that could be super helpful. Great to add in the middle of the room (dance floor), great to have massive cancellations at the walls (not make them shake, not bothering neighbours). :P

Learning something new every day :wink:

André

User avatar
Bill Fitzmaurice
Site Admin
Posts: 28619
Joined: Tue May 02, 2006 5:59 pm

Re: Yet another newbie, sorry guys

#15 Post by Bill Fitzmaurice »

Where you have cancellations is a three part equation, depending on the distance from the speaker to boundary, the speaker to the listener, and the listener to the boundary. Multiply the result by the number of boundaries and it gets very complicated. One may use devices like parabolic reflectors to control higher frequencies but not low frequencies.
'Shaking the walls' has no effect on what the neighbors will hear. It's not unusual for low frequencies to be louder on the other side of a wall than in the room, because the cancellations that are present in the room are not present on the other side.

Post Reply