Hello!
I am a mobile DJ and I am fed up with renting the subwoofer for my events. I want to build one for my own. I got a great deal for a pair of Eminence 18" woofers ( http://www.usspeaker.com/SigmaPro-18-1.htm ), I got them basically for free, brand new... Anyway, now I have the speakers, but how do I create the subwoofer box? What type of box gives the loudest bass? Let's say, I don't need no super-lows, just something above 30 or 35 Hz. Something simple, but efficient. And one more thing, I am a newbie. 🙁 Can you help?
I am a mobile DJ and I am fed up with renting the subwoofer for my events. I want to build one for my own. I got a great deal for a pair of Eminence 18" woofers ( http://www.usspeaker.com/SigmaPro-18-1.htm ), I got them basically for free, brand new... Anyway, now I have the speakers, but how do I create the subwoofer box? What type of box gives the loudest bass? Let's say, I don't need no super-lows, just something above 30 or 35 Hz. Something simple, but efficient. And one more thing, I am a newbie. 🙁 Can you help?
Big vented box for those babies. Download yourself a copy of WinISD Pro and have a play with some designs.
Start by downloading winisd pro from there website, its free.
Obtain the thiele/small parameters from the link you posted, and you can model the woofers in the program. Model the woofers in sealed, ported, 4th and 6th order bandpass, note the excursion of each type, the max spl, group delay and the box size required. The EBP will determine the recommended box type, see winisd help file for explanation on that.
The simplest to build and tune is the first one I mentioned, they get bigger, louder and harder to tune as the list progresses. There is more to it than that but a quick search on each type will get you a ton of important info to clarify the differences.
I am deliberately not giving you too much info because you will learn more and benefit more from searching on specific problems that come up rather than someone paraphrasing it all in this post. So as you progress and learn more you will be able to ask more specific questions. IF you want to stick with this hobby do the above or...
You might be able to search and find someone else who has done something with these drivers before, and you will definately find someone who has built some stage woofers before, search for this if you want a quick "cookbook" style design.
Obtain the thiele/small parameters from the link you posted, and you can model the woofers in the program. Model the woofers in sealed, ported, 4th and 6th order bandpass, note the excursion of each type, the max spl, group delay and the box size required. The EBP will determine the recommended box type, see winisd help file for explanation on that.
The simplest to build and tune is the first one I mentioned, they get bigger, louder and harder to tune as the list progresses. There is more to it than that but a quick search on each type will get you a ton of important info to clarify the differences.
I am deliberately not giving you too much info because you will learn more and benefit more from searching on specific problems that come up rather than someone paraphrasing it all in this post. So as you progress and learn more you will be able to ask more specific questions. IF you want to stick with this hobby do the above or...
You might be able to search and find someone else who has done something with these drivers before, and you will definately find someone who has built some stage woofers before, search for this if you want a quick "cookbook" style design.
Learn about bass horns and bang them in one of them!!!! Will make the crowd die. The main problems is that the horn is generaly quite big for frequencys down to 35hz and far more complicated to build. But can increase the spl by 15db
(thats 10/\1.5 times more efficient)
Or you could go for the bass reflex option. I have done that and found a need for horns as the power needed to get a decent amount of bass is a bit silly (bass reflex are about 1% efficent where as horns can be up to 60%)
It all depends on your woodworking skills and amount of time you have. If you want to put the effort in go for the horns they are well worth the effort!
http://www.speakerplans.com/index.php?id=1850horn
http://www.speakerplans.com/index.php?id=186horn
(thats 10/\1.5 times more efficient)
Or you could go for the bass reflex option. I have done that and found a need for horns as the power needed to get a decent amount of bass is a bit silly (bass reflex are about 1% efficent where as horns can be up to 60%)
It all depends on your woodworking skills and amount of time you have. If you want to put the effort in go for the horns they are well worth the effort!
http://www.speakerplans.com/index.php?id=1850horn
http://www.speakerplans.com/index.php?id=186horn
Ric_LV said:
Hi,
You have a pair 18" woofers, you can use JBL 4642A cabinet...
My friend have two pair TAD TL1801, use two 4642A cabinet...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
For PA purpose that's already super-low. Highpass @ 40 -45 Hz or higher is more common for mobile DJ's.
If you're making a basreflex I would advise you to tune around 40 -45 Hz. Otherwise you'll find the Sigma's will run out of Xmax quite fast.
For higher efficiency use a Band Pass Horn to keep things transportable. Sensitivity is ussually raised up to 6 dB (definatly not 15 dB, that would be superb). Stack 2 together for more low end extension:
http://groups.msn.com/SpeakerBuildingpics/shoebox.msnw?action=ShowPhoto&PhotoID=19
With kind regards Johan
From the looks and sound of it, I think Ric LV is wanting/needing something rather quickly and simple with good results.
With that in mind, I would recommend a simple ported enclosure of 8 cubic feet tuned to 45hz, both drivers in one enclosure and with two 6" ports 5" long each.
This is a simple design and will get you and your sub out on the road ASAP.
With that in mind, I would recommend a simple ported enclosure of 8 cubic feet tuned to 45hz, both drivers in one enclosure and with two 6" ports 5" long each.
This is a simple design and will get you and your sub out on the road ASAP.
Thank you all for your replies... The are very useful.. However my skills are low... Yes, I can make a good, cube-shaped box, but that's it... I think that if I will start to make horns, they will be made awfuly wrong and that would be just a waste of time. I will try to play with that software, you suggested. Thanx again!
diycoax, and anyone else who goes mobile with their own equipment is that monster subwoofer actually considered portable?
Wow, how normal is that sized sub?
Wow, how normal is that sized sub?
For mobile DJ use one single sub a side is more common for maximum flexibility. There are metal bars available to put in a mounting hole which you can easily incorporate in the sub. You can put the tops on the needed height on the other side of the bar, with or without safety. This also eliminates the need for special speaker stands. A single unit could be about 20-22" cubed.
Do you have filtering and amps for the sub?
Wkr Johan
Do you have filtering and amps for the sub?
Wkr Johan
My system is unusual. I use Rane MP4 mixer (I play MP3 from a computer and it sounds just as good as the CDs. You don't hear the difference in a disco) which is connected to a Rane SM82 stereo mixer, so that I have more inputs (for example, sometimes I have a co-DJ and then he just plugs in the SM82. I also connect a VCR to show a football game for example, or any other live event. And so on...), the SM82 is connected to a Rane SEQ 30L equalizer, so that I can tune the best sound. The SEQ 30L connects to a Rane SAC 23 active 3-way crossover. And then I have amplifiers - LEFT section: One for the sub and one for the mid and high (1ch for mid, 1ch for high); RIGHT section: the same as LEFT. I plan to add a distribution amplifier, so that I would have more signal outputs, then I could power more amps and therefore - power more speakers AND therefore boom a bigger room! 🙂 If I will have a nice budget, I plan to buy a couple of Turbosound TSW 718 subs ( http://www.turbosound.com/showroom/tsw718/index.html ). That's only the future ofcourse, but what do you think about them?
I did a sim on WinISD and in a vented box you can get 128db @ 1m with 600w input. This is with a 300L box tuned to 43 Hz, with an F3 @ 45 Hz. Ideally they should have a high pass (low cut) to prevent extreme excursion below tuning (which you probably have built into the power amps). For portability you could do two 150L boxes. You don't gain much by making them bigger. I found you could squeeze in another 2db output by making the box bigger (400L total) and tuning higher at 50 Hz, then using parametric eq to pull back the bump in response and feeding 1000w of power. This is a fair bit of complexity and hassle for another 2db, probably not worth it!
I've attempted to come up with a 6th order bandpass but WinISD has some nasty bugs but you would trade some extention to get some more output. Probably not worth it since they are very easy to mess up - a small misalignment goes very wrong very fast.
In a great big ugly horn with a lot of power you could get more like 135db, and the placement (corner, on the ground, against a back wall) makes a big difference. A single sigma 18 in a lab horn sized bass horn has more output than a lab horn (at least 6db more around 45 Hz).
I've attempted to come up with a 6th order bandpass but WinISD has some nasty bugs but you would trade some extention to get some more output. Probably not worth it since they are very easy to mess up - a small misalignment goes very wrong very fast.
In a great big ugly horn with a lot of power you could get more like 135db, and the placement (corner, on the ground, against a back wall) makes a big difference. A single sigma 18 in a lab horn sized bass horn has more output than a lab horn (at least 6db more around 45 Hz).
That sounds like a good system to me.
The Turbosound TSW 718 subs seem similar to the ES-18BPH (from the link on the previous page) in construction and performance except it's a double, but with low power handling.
The rate of performance can be reproduced with a single diy-BPH and top range drivers or the higher range of Turbosound. You don't have to touch a tool so it does has it's benefits.
Does the Rane only has a 15 Hz, 18 dB/ octave high pass? That's pretty low for achieving high power/ SPL levels. What's your power to spare?
With kind regards Johan
The Turbosound TSW 718 subs seem similar to the ES-18BPH (from the link on the previous page) in construction and performance except it's a double, but with low power handling.
The rate of performance can be reproduced with a single diy-BPH and top range drivers or the higher range of Turbosound. You don't have to touch a tool so it does has it's benefits.
Does the Rane only has a 15 Hz, 18 dB/ octave high pass? That's pretty low for achieving high power/ SPL levels. What's your power to spare?
With kind regards Johan
Actually I have no subs for my own... I always rent them 🙁 . I only own 2 pairs of Mid/High cabinets. A single cabinet has: Selenium D210Ti tweeter - http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=264-235
with HM25-25 horn ( http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-312&CFID=1565853&CFTOKEN=39998569 )
and TWO Selenium 12PW3 ( http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-334&ctab=9 )
connected paralell. So, in total, the cabinet has no filters, because I have an active 3 way x-over. Cabinet has mid and high speakeon inputs and paralell outputs, so I could daisy-chain the speakers. I am plannin to build more of these cabinets, so I could make larger parties, but I need a sub.. I am fed up with renting the subs... The mid/high cabinets can be made easy and cheaply, one cabinet costs me only speakers + 50$ for plywood, carpet, cables and connectors.
with HM25-25 horn ( http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-312&CFID=1565853&CFTOKEN=39998569 )
and TWO Selenium 12PW3 ( http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-334&ctab=9 )
connected paralell. So, in total, the cabinet has no filters, because I have an active 3 way x-over. Cabinet has mid and high speakeon inputs and paralell outputs, so I could daisy-chain the speakers. I am plannin to build more of these cabinets, so I could make larger parties, but I need a sub.. I am fed up with renting the subs... The mid/high cabinets can be made easy and cheaply, one cabinet costs me only speakers + 50$ for plywood, carpet, cables and connectors.
Do you rent the amps or are they yours, if the latter what power do they have? If not, what power are you supplying to your tops?
It's on the large size but not uncommon.
With kind regards Johan
Many mobile DJs use (to my mind) very small bass units, but I decided to build my own as nothing commercially available seemed up to the job.
Here's an old picture of the PA system I built and use:
- 3dB point occurrs at around 38Hz, and I think they sound wonderful! Uses all Fane drivers, with Colossus 18B 600 in the bass units.
OK, a bit of a handful to transport about, but it is always a compromise between portability or bass extension.
Here's an old picture of the PA system I built and use:
An externally hosted image should be here but it was not working when we last tested it.
- 3dB point occurrs at around 38Hz, and I think they sound wonderful! Uses all Fane drivers, with Colossus 18B 600 in the bass units.
OK, a bit of a handful to transport about, but it is always a compromise between portability or bass extension.
Actually, they do sound rather good - far better than many PA systems I've encountered, with no noticably large response peaks, meaning microphone feedback isn't too much of an issue. No nasty humps in the bass response either, as I tuned these for flat response rather than out and out efficiency.
I put this down to Fane having come up with a range of drivers which complement each other so well. The HF units needed to have 6dB of attenuation to match the rest, but that was a simple enough job.
I put this down to Fane having come up with a range of drivers which complement each other so well. The HF units needed to have 6dB of attenuation to match the rest, but that was a simple enough job.
The amplifiers for the subs are included in rental. They are usually 1-2 kW subs - each (I rent 2 subs). I use my own amplifiers for the mid/tops: 300w @ 8 Ohm. For the midrange I use full power, bit for tweeters I turn down the volume to 2/3 (two thirds) of the total power.
- Status
- Not open for further replies.