I want to build a subwoofer to match my pair of mission m73 and my Harman.
I will use the 250watt amplifier from partsexpress.com that you already should know! Here alink anyway.
I want to know if that amplifier is any good! It seem a good one and even better for the price!
I would use as driver, a alpine Type R 12". It's a car audio driver reputed for it's good sound quality. Do you think that this driver could do somehting good?
It's a driver that is a bit better in ported enclosure but I will do my box scealed and not ported, after all the most important for me is the Sound Quality and not the power...
The box will be a special one. It will have a net volume of 1 cubic feet.
The amplifier section will be in a other completly scealed section so that the woofer section will be perfectly scealed. Also I will use 1" MDF and it will be a front fireing sub. This box will be extrememently solid and I will use heavy brace. I will weight around 50-55lb.
I will also place it on spike! But not 4! I will use 3 of them to be sure that the contact will be perfect. I will put the box on a large and thick granite plate. If the box is too light I will also add a steel plate inside!
Here my questions:
Will 50lb for a 12" 300watt sub on spike will be allright?
Is the Type R could be a good sub for home?
Sceled box in home is allright? Even if all home woofer I know are ported?
Any other comentary of recomendations?
Here a Alpine type R link:
http://iweb.alpine-usa.com:7777/pls...21D&p_category=70&p_subcategory=150&p_main=10
I will use the 250watt amplifier from partsexpress.com that you already should know! Here alink anyway.
I want to know if that amplifier is any good! It seem a good one and even better for the price!
I would use as driver, a alpine Type R 12". It's a car audio driver reputed for it's good sound quality. Do you think that this driver could do somehting good?
It's a driver that is a bit better in ported enclosure but I will do my box scealed and not ported, after all the most important for me is the Sound Quality and not the power...
The box will be a special one. It will have a net volume of 1 cubic feet.
The amplifier section will be in a other completly scealed section so that the woofer section will be perfectly scealed. Also I will use 1" MDF and it will be a front fireing sub. This box will be extrememently solid and I will use heavy brace. I will weight around 50-55lb.
I will also place it on spike! But not 4! I will use 3 of them to be sure that the contact will be perfect. I will put the box on a large and thick granite plate. If the box is too light I will also add a steel plate inside!
Here my questions:
Will 50lb for a 12" 300watt sub on spike will be allright?
Is the Type R could be a good sub for home?
Sceled box in home is allright? Even if all home woofer I know are ported?
Any other comentary of recomendations?
Here a Alpine type R link:
http://iweb.alpine-usa.com:7777/pls...21D&p_category=70&p_subcategory=150&p_main=10
That driver isn't too cheap... $349can.
Since you're in Canada, you should check out the Adire drivers at www.creativesound.ca (Shiva, Tempest, Maelstrom)
Some of them have $1 shipping to anywhere in Canada.
Also, as an alternative to the PE amp, you could check out the Adire AVA250 ($1 shipping as well). I've heard that shipping from PE to Canada isn't too cheap...
Anyways, to be fair, I have never heard the Alpine, but I would spend $50can more and go for the 18" Maelstrom!
Since you're in Canada, you should check out the Adire drivers at www.creativesound.ca (Shiva, Tempest, Maelstrom)
Some of them have $1 shipping to anywhere in Canada.
Also, as an alternative to the PE amp, you could check out the Adire AVA250 ($1 shipping as well). I've heard that shipping from PE to Canada isn't too cheap...
Anyways, to be fair, I have never heard the Alpine, but I would spend $50can more and go for the 18" Maelstrom!
Probably a good plan. I "built" the Titanic II "kit" a year or so back and have been nothing but pleased. The only thing I continue to ponder is what would a passive version with an external amp be like. I've noticed the typical plate amps appear to have fairly mediocre THD+N figures. I've wondered what the result would be if a high power version of a D.Self "Blameless Amp" were used or a high power version of the ESP P3A. Maybe is doesn't make any difference ot low frequencies, but I'd like to hear for myself someday.
seangoesbonk said:
Don't worrie! lol this sub will cost me 220$ can. ! Nice deal!
I seen that my post suck! ...lol
Anyway I will use that amp and I will build a nice ported box, now I trying to do some meserement...
I will post soom some mesurmeent, box size and subwoofer Thiele small parameter...
What made you decide to go with a ported box instead of sealed? Generally speaking, sealed boxes sound better.
the biggest reason for going ported over sealed is the massively increased deep bass that ported enclosures give, for something like HT which is what most subs are used for the sound quality is not noticed, only in refined tight music can a difference be seen, betwwen 2 subs with equal power and drivers.
I don't believe sealed boxes necessarily sound better. I think that rap got started because so many people have built poorly aligned ported boxes with speakers not suited for the task (Stay away from Boom Box alignments) (Generally prefer speakers with Qt below .4) (make sure the port tuning is no more than 1/2 octave above the lowest note you want to allow, & filter below that) . A ported box with a low Qt speaker that can be aligned to go down as deep as your desire dictates with low passband ripple will outperform an equivalent sealed enclosure in my book (get low louder, with less distortion) aka., sound better. It's a beautiful thing the way a port gradually kicks in adding the extra air volume needed at the low end to bring up the Max SPL on par with the upper band of the sub. It all starts with the speaker though. T/S parameters
are more critical for ported.
are more critical for ported.
While ported boxes can have slightly better SQ at a certain freq, sealed boxes have a flatter freq response over the entire sub's freq range making it more suitable to handle both tasks of HT and music.
SkinnyBoy said:
umm... BULL!!!
do ported... and don't use a crappy Alpine sub....
Bull right back at you! Go sealed and you won't be diappointed.
One advantage to going ported is that you can convert it to sealed by blocking the port (listening to music for example) but you can't convert sealed to ported, the downside is the box needs to be bigger for ported. Personally I went down the sealed route with a Linkwitz transform, smaller box than ported, good low-frequency response, higher cost unfortunately.
Stephen D
Don't want to see this turn into a sealed verses ported mudsling. Both have their place. Some misconceptions & disinformation are obviously in circulation though. There is no inherent advantage to either as regards to flatness of response throughout the passband except that ported can maintain flat response deeper but when it does reach it's f3 roll off point it rolls off steeper than sealed. The advantage of comparative shallow roll off of sealed is generally easily overridden by the greatly extended f3 point of ported. Easily an octave extension in most cases, & the real clincher here is this octave extension applies to flatness of Max SPL curve as well.
There is really only 2 areas I can think of that sealed can claim an performance advantage (both of which can be rendered irrelevant for sub design) & that is -
1) [Less group delay]. - This is IMO the single most contributing factor to it's reputation as having tight sounding fast acting bass... well, because that's what group delay effects. But at very deep tunings of a sub cab this is pretty nearly a non issue as room Q & delay build up becomes the dominant audible effect in the average environment. I do think this is one factor that could make sealed more suitable than ported for mid bass enclosure though.
2) [Maintains air loading full range below cutoff]. The old problem of port reversing phase past the half octave or so below tuning, thus unloading the speaker, sending it flying across the room.
😱 . Not a problem in a sub application as long as you choose a speaker & design with low enough tuning & perhaps add a little infra sub filtering. This is though also another reason sealed may fair better for mid bass.
I recommend running comparative model alignments in software that can plot {Max SPL / Freq} as well as {Transfer function Freq response}. WinISD Pro is excellent Freeware that can do this & display multiple alignment graphs simultaneously for easy comparison. It comes with a fairly large database of driver T/S parameters to play with. If you have it or get it, a real simple, revealing & applicable comparison would be to choose the *Adire Audio Shiva 2* driver from the data base & run a modeling sim in a ported QB3 alignment & also in a sealed buterworth (.707/ maximally flat) alignment, & view their comparative plots for Max SPL & Transfer function magnitude (Freq response out with given flat response voltage source input signal). Particularly Max SPL as this is really where the rubber meets the road. That's the max sound pressure level
achievable vs. freq..
Don't want to see this turn into a sealed verses ported mudsling. Both have their place. Some misconceptions & disinformation are obviously in circulation though. There is no inherent advantage to either as regards to flatness of response throughout the passband except that ported can maintain flat response deeper but when it does reach it's f3 roll off point it rolls off steeper than sealed. The advantage of comparative shallow roll off of sealed is generally easily overridden by the greatly extended f3 point of ported. Easily an octave extension in most cases, & the real clincher here is this octave extension applies to flatness of Max SPL curve as well.
There is really only 2 areas I can think of that sealed can claim an performance advantage (both of which can be rendered irrelevant for sub design) & that is -
1) [Less group delay]. - This is IMO the single most contributing factor to it's reputation as having tight sounding fast acting bass... well, because that's what group delay effects. But at very deep tunings of a sub cab this is pretty nearly a non issue as room Q & delay build up becomes the dominant audible effect in the average environment. I do think this is one factor that could make sealed more suitable than ported for mid bass enclosure though.
2) [Maintains air loading full range below cutoff]. The old problem of port reversing phase past the half octave or so below tuning, thus unloading the speaker, sending it flying across the room.
😱 . Not a problem in a sub application as long as you choose a speaker & design with low enough tuning & perhaps add a little infra sub filtering. This is though also another reason sealed may fair better for mid bass.
I recommend running comparative model alignments in software that can plot {Max SPL / Freq} as well as {Transfer function Freq response}. WinISD Pro is excellent Freeware that can do this & display multiple alignment graphs simultaneously for easy comparison. It comes with a fairly large database of driver T/S parameters to play with. If you have it or get it, a real simple, revealing & applicable comparison would be to choose the *Adire Audio Shiva 2* driver from the data base & run a modeling sim in a ported QB3 alignment & also in a sealed buterworth (.707/ maximally flat) alignment, & view their comparative plots for Max SPL & Transfer function magnitude (Freq response out with given flat response voltage source input signal). Particularly Max SPL as this is really where the rubber meets the road. That's the max sound pressure level
achievable vs. freq..
Stephen D
One more word on max SPL. In the end all that maters is that the system can meet the SPL vs. freq requirements of you in your listening environment, so if a given speaker in a sealed cab has enough cone area & excursion capability to reach that goal, given that it's much simpler to design & construct, going sealed is a perfectly fine choice.
One more word on max SPL. In the end all that maters is that the system can meet the SPL vs. freq requirements of you in your listening environment, so if a given speaker in a sealed cab has enough cone area & excursion capability to reach that goal, given that it's much simpler to design & construct, going sealed is a perfectly fine choice.
grampi said:
I decided to go scealed to try to extend the F3 to around 23-25hz
In my case the sub will need to be of a nice SQ, and also i want it as a low frequency extention. Now my speaker go doun to 49hz! Not enought! I don't want power, just quality!
SkinnyBoy said:
umm... BULL!!!
do ported... and don't use a crappy Alpine sub....
Why not alpine? The compagnie suck? The type R sub suck? Or because of it's parameters it won't be a good sub?
What sub would you recomand for 150 US$ max... or around 200-220$ CAN? I want 12"
Also I find that 1 cu FT for a box is small! Is it me?
If I go ported calculation are harder and to achive a perfect box it's realy hard! Each ported box is not perfect! I think that you can't predict the final result and in my case I don't want to buid 2-3 box.
If I go ported anyway it will be a slot port.
Member
Joined 2002
I was going to buy 2 of them alpine speakers also 2 x 15" and run them with my av800's i was told that those subwoofers will play down very low and still have lots of power. My ideal box for them would have been ported just because it lets them breath and play low frequency's.
J'
Ps 220 per sub is a good rice.. : O )
J'
Ps 220 per sub is a good rice.. : O )
Stephen D
You have been disinformed. For a given speaker, sealed will usually have higher f3 than ported.
You really should download WinISD Pro http://www.linearteam.dk/default.aspx?pageid=winisdpro & do some box simulations on sealed & ported with various drivers. It's freeware & very easy to learn. Will be very educational for you & & will help you choose a proper speaker & box design.
Some general rule of thumb for ported design & speaker choice.
If you want it to extend low enough to suffice for home theater as well as music, you don't want a port tuning much above 21 Hz. For most commercial music a port tuning of no higher than 36 Hz is acceptable. Classical music Pipe organs & such will put you back at a recommended 21 Hz max (roughly).
Qt & fs value of woofer is about the best quick glance reference for rough guestimating how it will tune well in a ported enclosure.
At Qt of .38 optimum flat response tuning will be same as speakers fs. At lower Qt optimum tuning will generally be higher than fs. At higher Qt optimum tuning will generally be lower than fs. For ported use generally limit speaker choice to Qt no higher than roughly .45 (.3 to .4 is my preferred range though slight deviations either way can work depending on fs, Vas & other parameters). Generally lower Qt result in smaller box design than High Qt though Vas has some impact here as well.
Mantronic said:
You have been disinformed. For a given speaker, sealed will usually have higher f3 than ported.
You really should download WinISD Pro http://www.linearteam.dk/default.aspx?pageid=winisdpro & do some box simulations on sealed & ported with various drivers. It's freeware & very easy to learn. Will be very educational for you & & will help you choose a proper speaker & box design.
Some general rule of thumb for ported design & speaker choice.
If you want it to extend low enough to suffice for home theater as well as music, you don't want a port tuning much above 21 Hz. For most commercial music a port tuning of no higher than 36 Hz is acceptable. Classical music Pipe organs & such will put you back at a recommended 21 Hz max (roughly).
Qt & fs value of woofer is about the best quick glance reference for rough guestimating how it will tune well in a ported enclosure.
At Qt of .38 optimum flat response tuning will be same as speakers fs. At lower Qt optimum tuning will generally be higher than fs. At higher Qt optimum tuning will generally be lower than fs. For ported use generally limit speaker choice to Qt no higher than roughly .45 (.3 to .4 is my preferred range though slight deviations either way can work depending on fs, Vas & other parameters). Generally lower Qt result in smaller box design than High Qt though Vas has some impact here as well.
people put 500watt in those 300watt RMS 12"
And yes I think that this sub play a bit better in ported but i will go scealed, they work well scealed too... And for the heat factor, 275 watt won't kill them!
This plate amp have been said to have poor SQ? but compared to general subwoofer on the market it should be good? After all every sub are running from plate amp and a 400-600$ sub probably don't have very good amp?
And yes I think that this sub play a bit better in ported but i will go scealed, they work well scealed too... And for the heat factor, 275 watt won't kill them!
This plate amp have been said to have poor SQ? but compared to general subwoofer on the market it should be good? After all every sub are running from plate amp and a 400-600$ sub probably don't have very good amp?
Tanks stephen D
I have Win ISD
I also did some personal calculations.
The Fs is 28hz and the calculation say to port my box at around 29,766 HZ, I find it a bit high!
The F3 would be af 30,54HZ
I would need a box of 47,615 liter... To be honest I don't like these calculation!
It's for that I wanna go scealed, much easy!
I have Win ISD
I also did some personal calculations.
The Fs is 28hz and the calculation say to port my box at around 29,766 HZ, I find it a bit high!
The F3 would be af 30,54HZ
I would need a box of 47,615 liter... To be honest I don't like these calculation!
It's for that I wanna go scealed, much easy!
Re: Stephen D
Hi Stephen,
Is that from a power handling perspective or a quality perspective? I'm guessing power handling. I've just been modeling some new cabinets for my vifa M26wr-09-08 10" drivers and came up with a tuning freq of 33Hz in an 85L cabinet (based on my measured specs, not published ones)....
I use the current boxes for HT and I think the tuning is somewhere around the 36Hz mark, and haven't had any problems, but I can't play it too loud, as the neighbors would complain...... when I finally get round to this and set up an active xover, should I put a high pass of about 25Hz to be on the safe side?
Tony.
Stephen D said:
Hi Stephen,
Is that from a power handling perspective or a quality perspective? I'm guessing power handling. I've just been modeling some new cabinets for my vifa M26wr-09-08 10" drivers and came up with a tuning freq of 33Hz in an 85L cabinet (based on my measured specs, not published ones)....
I use the current boxes for HT and I think the tuning is somewhere around the 36Hz mark, and haven't had any problems, but I can't play it too loud, as the neighbors would complain...... when I finally get round to this and set up an active xover, should I put a high pass of about 25Hz to be on the safe side?
Tony.
Re: Re: Stephen D
A little of both but mostly power handling (or excursion handling)as you guess. And of course it's all theorizing upon the ideal. As you know, as you extend below the half octave below tuning freq of a ported enclosure the excursion goes way up with little acoustic output because the port becomes out of phase & unloads the speaker. HT could have some pretty low stuff down there below 20 Hz with earth quakes & bomb blasts & such hence the recommended low tuning for safety of the woofers sake. It depends though on how loud you listen though and most of the time there really isn't all that much down there & the speaks can take a fair amount of abuse. My current HiFi sub which is also used for what little HT use I indulge in is tuned at 31 Hz if I remember right (built it about 10 years ago) & I don't have a HP filter on it & have not felt the need to but I don't do that much HT & I don't go overboard with the volume. It also seems to me there's a pretty near fair enough amount of wall & but shakin' rumble from those earth quakes & bomb blasts in the 30 Hz range to enjoy so I'm not sure how much of a quality issue it is for HT. For pop music the lowest note on a 5-6 string bass is around 31.5 HZ & that's why I recommend ported tuning no higher than 36 HZ. I can't tell you how many 5-6 string bass players I've known to shread their speakers because their cab was tuned to like 40 - 45 HZ! That's OK for a 4 string bass! Of course who knows how low the synthetic bass drones are on some of those RAP tunes & then Berry White is probably below that..
As for pipe organ I believe it goes down to something like 15 HZ so if your into listening to pipe organ & you want to be a purist about it (& most pipe organ fans are purist about it) you'd probably want at least that 21 Hz max tuning freq., so that would qualify as a quality issue.
Should you HP filter at 25 HZ...? May not be necessary for you but wouldn't hurt & may tighten up the upper bass response whenever there is accompanying rumble in the program that would just be flapping your speakers & since you're building the xover anyway I would & yes 25 Hz I think would be about right for your 33 Hz sub. Like I said though I've yet to HP filter mine but that's somewhat because it would require me to get up off the couch & build a HP filter.
:
wintermute said:
A little of both but mostly power handling (or excursion handling)as you guess. And of course it's all theorizing upon the ideal. As you know, as you extend below the half octave below tuning freq of a ported enclosure the excursion goes way up with little acoustic output because the port becomes out of phase & unloads the speaker. HT could have some pretty low stuff down there below 20 Hz with earth quakes & bomb blasts & such hence the recommended low tuning for safety of the woofers sake. It depends though on how loud you listen though and most of the time there really isn't all that much down there & the speaks can take a fair amount of abuse. My current HiFi sub which is also used for what little HT use I indulge in is tuned at 31 Hz if I remember right (built it about 10 years ago) & I don't have a HP filter on it & have not felt the need to but I don't do that much HT & I don't go overboard with the volume. It also seems to me there's a pretty near fair enough amount of wall & but shakin' rumble from those earth quakes & bomb blasts in the 30 Hz range to enjoy so I'm not sure how much of a quality issue it is for HT. For pop music the lowest note on a 5-6 string bass is around 31.5 HZ & that's why I recommend ported tuning no higher than 36 HZ. I can't tell you how many 5-6 string bass players I've known to shread their speakers because their cab was tuned to like 40 - 45 HZ! That's OK for a 4 string bass! Of course who knows how low the synthetic bass drones are on some of those RAP tunes & then Berry White is probably below that..
As for pipe organ I believe it goes down to something like 15 HZ so if your into listening to pipe organ & you want to be a purist about it (& most pipe organ fans are purist about it) you'd probably want at least that 21 Hz max tuning freq., so that would qualify as a quality issue.
Should you HP filter at 25 HZ...? May not be necessary for you but wouldn't hurt & may tighten up the upper bass response whenever there is accompanying rumble in the program that would just be flapping your speakers & since you're building the xover anyway I would & yes 25 Hz I think would be about right for your 33 Hz sub. Like I said though I've yet to HP filter mine but that's somewhat because it would require me to get up off the couch & build a HP filter.
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