Subwoofer design

[coloradoxc]

Hello. I am planning on building a powered vented sub woofer with "two" Dayton TIT400C-4 15" Titanic Mk III Subwoofer 4 Ohm for home theater application. The drivers both have a SVC and can be wired in series for 8 ohms or parallel into 2 ohms. Each driver can handle 800 watts RMS power. I cannot seem to find a plate or rack sub amplifier that will power this home stereo sub with a two ohm load. Most amps I find cannot transfer enough power to the 8 ohm configuration to reach the 800 watt RMS value. The only option I can think of is using the Dayton SA1000 Subwoofer Amplifier Rack Mountable. I would have the drivers separately connected to each channel of the amp. Even if I do this I do not know if the specs are saying that they deliver 950 watts into each channel at 4 ohms or 425 split between the channels. I really would appreciate some tips, advice, and or help. Thanks to those who take the time to read this and help me.

 

[annunaki]

Hello. I am planning on building a powered vented sub woofer with "two" Dayton TIT400C-4 15" Titanic Mk III Subwoofer 4 Ohm for home theater application. The drivers both have a SVC and can be wired in series for 8 ohms or parallel into 2 ohms. Each driver can handle 800 watts RMS power. I cannot seem to find a plate or rack sub amplifier that will power this home stereo sub with a two ohm load. Most amps I find cannot transfer enough power to the 8 ohm configuration to reach the 800 watt RMS value. The only option I can think of is using the Dayton SA1000 Subwoofer Amplifier Rack Mountable. I would have the drivers separately connected to each channel of the amp. Even if I do this I do not know if the specs are saying that they deliver 950 watts into each channel at 4 ohms or 425 split between the channels. I really would appreciate some tips, advice, and or help. Thanks to those who take the time to read this and help me.

What about finding two two channel rack mount amplifiers that can be bridged into an 8 ohm load? I am not sure of your budget but this may be the way to go.

That sub will do very well with as little as 500 watts in a vented application.

What size enclosure are you building? What frequency are you tuning to, and what will you be using for vents?

These items can have bearing on how big of an amplifier is needed/necessary as well.

 

[chkngreez]

Sounds to me like a very good match for those subs would be a Behringer EP4000. You can pick one up for around $300 new, shipping included. In fact go here http://www.americanmusical.com/Item--i-BEH-EP4000-LIST and have them price match here http://www.karaokeequipment.com/behringer-ep4000-professional-power-amp-amplifier-ep-4000.html I would suggest running the amp @ 8 ohm bridged. This should provide you with more than adequate power. Also, with a vented sub, you will probably need a good hpf to keep from bottoming out. Might I suggest http://www.creativesound.ca/details.php?model=B-1 ? You will also probably need an rca to xlr connector, availabe from sweetwater.com. ($7)Good luck.

 

[coloradoxc]

Using BassBox Pro 6 I created a 485.7 liter box tuned to 19.1 Hz. I will be using pvc piping for the vent. I would like to stay under $500 for the sub amp since I still need to buy materials to build the large enclosure.

Are you talking about bridging 2 separate 2 channel amplifiers together? Is that possible? I can find plenty of 4 ohm stable plate amps. So what i think I might end up doing is buying 2 Bash 500W Digital Subwoofer Amplifiers. Each deliver 500 watts RMS into a 4 ohm load. Please, if anyone can help me figure out how to power these guys let me know. I might end up building two enclosures if I can't find an amp to power these 2 guys. thanks

 

[t3steve]

Thats over 17 ft^3!
If you really want to go that big you could build a THT using only 1 15incher and really have some good sound.


Steve

 

[coloradoxc]

Thanks chkngreez. Since this is a stereo amplifier the speaker terminals are not hooked in parallel, right? In this case since there are two channels wouldn't it be easier to just hook each sub within the enclosure separately to each channel. The amp specs say 2 x 1,400 Watts into 4 Ohms. I am assuming that means there are two channels. In this case 1400 Watts per sub would be more than enough, perfect. My only other concern would be the "Selectable low-frequency filters (30 Hz or 50 Hz) remove distracting infra-sound". If I am using this for low frequency reproduction this sounds like it might be an issue. Do you know if you can turn this off? Also, I am guessing since this is not designed as a sub amp I would need to buy a cross over filter to send only 500 Hz and below signals. Thanks again for the reply. If you can clear all that up I would be much appreciative!

 

[t3steve]

Link
sombody on this board has already built one, can't remember who

http://www.billfitzmaurice.com/THT.html

 

[coloradoxc]

Hey t3steve. The largest dimension would be 4.3 feet which isn't a big problem for a college student living in a house off campus with a basement. But, I had never heard of a THT subwoofer until you mention it today. As it already may sound, I am new to audio and wanted to start off easy with a vented enclosure. However, you seem like you could help me out with building a better suited enclosure. How advanced are THT enclosures when it comes to construction?

 

[chkngreez]

Thanks chkngreez. Since this is a stereo amplifier the speaker terminals are not hooked in parallel, right? In this case since there are two channels wouldn't it be easier to just hook each sub within the enclosure separately to each channel. The amp specs say 2 x 1,400 Watts into 4 Ohms. I am assuming that means there are two channels. In this case 1400 Watts per sub would be more than enough, perfect. My only other concern would be the "Selectable low-frequency filters (30 Hz or 50 Hz) remove distracting infra-sound". If I am using this for low frequency reproduction this sounds like it might be an issue. Do you know if you can turn this off? Also, I am guessing since this is not designed as a sub amp I would need to buy a cross over filter to send only 500 Hz and below signals. Thanks again for the reply. If you can clear all that up I would be much appreciative!

You can disable the 30 or 50 hz filter. The reckhorn I linked to will provide you with both a lpf adjustable up to 150hz and a hpf adjustable down to 12hz. This will give you all the filtering you need. As far as running the amp in stereo, that is fine if you want to do that, but I think bridged 8ohm configuration would be better. The amps have been tested, they're basically a re-badged EP2500. The test results are here http://www.avsforum.com/avs-vb/showthread.php?p=10755565#post10755565 , remember this is true wattage. Refer to the manual on the behringer website. This may clear up any questions you have. http://www.behringer.com/EN/Products/EP4000.aspx
Also, might I suggest a slot port box? I built one for a single 12" behind the couch and it sounds wonderful. Here is another link to my build http://www.hometheatershack.com/forums/ported-subwoofer-build-projects/29867-looking-little-help-shack.html

 

[highfigh]

Hello. I am planning on building a powered vented sub woofer with "two" Dayton TIT400C-4 15" Titanic Mk III Subwoofer 4 Ohm for home theater application. The drivers both have a SVC and can be wired in series for 8 ohms or parallel into 2 ohms. Each driver can handle 800 watts RMS power. I cannot seem to find a plate or rack sub amplifier that will power this home stereo sub with a two ohm load. Most amps I find cannot transfer enough power to the 8 ohm configuration to reach the 800 watt RMS value. The only option I can think of is using the Dayton SA1000 Subwoofer Amplifier Rack Mountable. I would have the drivers separately connected to each channel of the amp. Even if I do this I do not know if the specs are saying that they deliver 950 watts into each channel at 4 ohms or 425 split between the channels. I really would appreciate some tips, advice, and or help. Thanks to those who take the time to read this and help me.

The SA1000 isn't two channels, it just has two sets of terminals. Better to find two 8 Ohm or 2 Ohm woofers.

How loud do you want it? 900W into 2 speakers with 89dB sensitivity will be close to 125dB without any gain from the room.

 

[coloradoxc]

Does anyone have the plans to the Bill Fitzmaurice THT enclosure. t3steve recommended constructing a tube enclosure instead of the standard vented since my version would be large. I have plenty of tools to build a complicated box since I have full access to a college wood shop, metal shop, machine shop, and tech ed friends. Also, thanks for the help on the amplifiers. If I build two of the THT enclosures with each dayton titanic MK IIIs i'll be able to power it with that one amp.

 

[t3steve]

I don't have any actual experience with them but based on the research I have done on the internet the THT looks really good.

So you can take everything I have said with a grain of salt.

Here is another link
http://www.avsforum.com/avs-vb/showthread.php?t=1194093

 

[coloradoxc]

chkngreez, when you mention true watts does that mean peak wattage or RMS? I decided to go with Bill Fitzmaurice's THT subwoofers. So, now I am going to build two separate THT with the 4 ohm sub drivers. How would you suggest powering the two separate subs with the Behringer 4000? I'm sorry if I am sounding repetitive. If I hook them up in stereo mode I would be getting 700 watts RMS right? I hope thats the case. Thanks again for all your help.

 

[annunaki]

Using BassBox Pro 6 I created a 485.7 liter box tuned to 19.1 Hz. I will be using pvc piping for the vent. I would like to stay under $500 for the sub amp since I still need to buy materials to build the large enclosure.

Are you talking about bridging 2 separate 2 channel amplifiers together? Is that possible? I can find plenty of 4 ohm stable plate amps. So what i think I might end up doing is buying 2 Bash 500W Digital Subwoofer Amplifiers. Each deliver 500 watts RMS into a 4 ohm load. Please, if anyone can help me figure out how to power these guys let me know. I might end up building two enclosures if I can't find an amp to power these 2 guys. thanks

My apologies, I was assuming they were 8 ohms each. In that case I would also suggest an EP4000. Use one sub on each channel.

As for your enclosure, I have also modeled this driver. The best balance I could find between size, extension, & response was an 8.0ft^3 (226.50L) enclosure (per driver) tuned to 19hz. Vent velocity is a major issue with this driver. To keep the vent velocity compression free through the audible range one will need to utilize a vent 4.0" x 17.0" x 56.4" long.

Using a single 4" vent or even two of them will result in audible vent noise/compression beginning at just 27hz (using two 4" vents).

The vent velocity figures assume 800 watts rms input power.

Have you purchased these drivers yet?

What are the goals for your system overall?

There may be better options for you depending upon what your goals are for this system. If you have them already, it is fine as well as they are nice woofers. They just need large enclosures.