I'm new here, my name is Simon.
I need help to build a Tempest enclosure. It will be my first enclosure. It will be a subwoofer for home audio usage.
The box can be huge if needed. If it can be simple and sounds good, great. It must sound good, so if it needs to be complicated, I will do that.
I want to have a flat frequency response, the flatter the better. It must be flat to at least 19 Hz.
My goal is to build a better subwoofer than the brand new PB10-ISD from SVS which is powered by a 300W RMS amplifier and sold for 429$ USD. That subwoofer is a ported design and achieved a frequency response of ±1 dB from 19 Hz to 150 Hz at 105 dB in this test: http://www.hometheaterhifi.com/volume_11_4/svs-pb10-subwoofer-10-2004.html I know I will probably not achieve a frequency response that flat, but at least I want to try to do ±3 dB or better.
I checked on the AdireAudio website and saw that they are giving three reference designs for vented or sealed Tempest. I was thinking to go with the vented design to be able to go lower with more power, since box since doesn't matter. It's a good idea, or I would need to go sealed to achieve my goal?
I downloaded Adire Audio LspCAD. I would like to download these reference designs into it, to look at the frequency response. I didn't find them on the Adire Audio website. Someone knows where I can find them?
If someone have better designed boxes than the reference that Adire Audio gives, I can do that.
Thank you very much for your help, it is really appreciated!
Simon
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P.S.: Which forums should I use to post about how to build an amplifier for this subwoofer design? Since I want to build something that costs less than 429$ USD, there's about 200$ USD or less that's left to build the amplifier section. I want it to sound good, but I want it to be cheap, and really powerful. 750W RMS would be the best, but I doubt I can do that with 200$ USD.
So, which forum is better for cheap powerful amplifier???
Solid state?
Class D?
Chip amp?
I'm studying in computer engineering so I know my basics in electronics.
Thank you very much again!
Simon
I need help to build a Tempest enclosure. It will be my first enclosure. It will be a subwoofer for home audio usage.
The box can be huge if needed. If it can be simple and sounds good, great. It must sound good, so if it needs to be complicated, I will do that.
I want to have a flat frequency response, the flatter the better. It must be flat to at least 19 Hz.
My goal is to build a better subwoofer than the brand new PB10-ISD from SVS which is powered by a 300W RMS amplifier and sold for 429$ USD. That subwoofer is a ported design and achieved a frequency response of ±1 dB from 19 Hz to 150 Hz at 105 dB in this test: http://www.hometheaterhifi.com/volume_11_4/svs-pb10-subwoofer-10-2004.html I know I will probably not achieve a frequency response that flat, but at least I want to try to do ±3 dB or better.
I checked on the AdireAudio website and saw that they are giving three reference designs for vented or sealed Tempest. I was thinking to go with the vented design to be able to go lower with more power, since box since doesn't matter. It's a good idea, or I would need to go sealed to achieve my goal?
I downloaded Adire Audio LspCAD. I would like to download these reference designs into it, to look at the frequency response. I didn't find them on the Adire Audio website. Someone knows where I can find them?
If someone have better designed boxes than the reference that Adire Audio gives, I can do that.
Thank you very much for your help, it is really appreciated!
Simon
-----------------------------------------------------------------------------------
P.S.: Which forums should I use to post about how to build an amplifier for this subwoofer design? Since I want to build something that costs less than 429$ USD, there's about 200$ USD or less that's left to build the amplifier section. I want it to sound good, but I want it to be cheap, and really powerful. 750W RMS would be the best, but I doubt I can do that with 200$ USD.
So, which forum is better for cheap powerful amplifier???
Solid state?
Class D?
Chip amp?
I'm studying in computer engineering so I know my basics in electronics.
Thank you very much again!
Simon
I like the LowQ vented design from Adire. You don't need 750W to get good performance. 200 - 250W should be plenty although there's nothing wrong with having headroom. Are you using this for music, HT, both? If both, what ratio? 50/50, 70/30? In many cases the difference in performance can be a result of the room more than the sub itself. I like using the parametric equalizer portion of the Behringer Feedback Destroyer Pro to adjust for room modes.
The ratio is probably 70% for music and 30% for movies.
I know that the room is going to have alot of importance.
Where can I find the design of the LowQ vented design from Adire? What will be the frequency response and Max SPL level?
Thanks!
I know that the room is going to have alot of importance.
Where can I find the design of the LowQ vented design from Adire? What will be the frequency response and Max SPL level?
Thanks!
Vented Tempest Designs
It's the Adire Alignment Design. Q of .57, Fc of 20Hz, within .5db to 11zHz. 214L cab tuned to 15.4Hz.
I use this in my HT. It does have a bit of a mid-bass hump. This is ok for me because of my room. If you're looking for maximally flat response go with the EBS design. It's a huge box but you said that doesn't matter and you will sacrifice some SPL for movies.
It's the Adire Alignment Design. Q of .57, Fc of 20Hz, within .5db to 11zHz. 214L cab tuned to 15.4Hz.
I use this in my HT. It does have a bit of a mid-bass hump. This is ok for me because of my room. If you're looking for maximally flat response go with the EBS design. It's a huge box but you said that doesn't matter and you will sacrifice some SPL for movies.
Does the 0.5 dB down to 11 Hz means it will be down 0.5 dB at 11 Hz versus 20 Hz reference point?
Can I load this design in LspCAD to see the frequency response curve and maximum SPL levels?
Can you answer my last question under the P.S. question please?
Thanks!
Can I load this design in LspCAD to see the frequency response curve and maximum SPL levels?
Can you answer my last question under the P.S. question please?
Thanks!
The Adire reference designs are the best available for the Tempest. I built the EBS Tempest and Eq'd it flat to about 16 Hz. While watching movies I get about 118 dB in the listening position but I usually listen with 105 dB peaks. I use 250W and it sounds great. No need for more power with the low Q alignments.
An EQ is really necessary if you want a flat response. The SVS maybe very flat at ground plane but who knows what it will look like in your room.
As for a DIY amp, you could try asking in the solid state forum here. I dont know of any kits like that though. Parts Express has 250W amps for like $130.
An EQ is really necessary if you want a flat response. The SVS maybe very flat at ground plane but who knows what it will look like in your room.
As for a DIY amp, you could try asking in the solid state forum here. I dont know of any kits like that though. Parts Express has 250W amps for like $130.
Can I put these plates amp like the one from partsexpress directly on the back wall of the enclosure or I need to shield it from the magnetic field?
Also, since you're Canadian, how much I will be charged for duties and taxes if I order from partsexpress?
Is there good manufacturers of cheap subwoofer plate amplifiers in Canada?
Will the rumble filter hinder performance at very low frequencies?
Thank you very much again!
Also, since you're Canadian, how much I will be charged for duties and taxes if I order from partsexpress?
Is there good manufacturers of cheap subwoofer plate amplifiers in Canada?
Will the rumble filter hinder performance at very low frequencies?
Thank you very much again!
Also, if I put this amplifier on the back of the enclosure, will my enclosure be weaker, flex or leak air since it's not veneer all around like before?
Sorry for all these questions!
Sorry for all these questions!
Go ahead and put the amp in the enclosure. That's how they're designed to be used. Following the Adire construction plans should allow you space between the braces to place an amp. The braces will provide you with structural integrity. I've heard of people building chip amps for subs but by the time you buy all the parts you've exceeded the price of a plate amp and you still don't have an adjustable XO and phase control.
If you REALLY want to build a sub amp, the best place I know is Elliott Sound Products . They have excellent articles, a forum and projects for which you can buy PCB's and you are given excellent instructions.
They have high power MOSFET amps as well as a 500W amp (which is more than you need for Tempest).
The cost of a diy sub amp is quite high and I don't think it's worth it. It's not hard to get cheap power to your subs, for less than it costs to diy. (You won't often hear me say something is not worth diy'ing)
As the others have stated, getting a flat response is more about the room than the design of the sub. The way to get a sub flat in room to +/- 3db is with eq from something like BFD.
Have a look into:
* BFD (Behringer Feedback Destroyer)
* room modes
They have high power MOSFET amps as well as a 500W amp (which is more than you need for Tempest).
The cost of a diy sub amp is quite high and I don't think it's worth it. It's not hard to get cheap power to your subs, for less than it costs to diy. (You won't often hear me say something is not worth diy'ing)
As the others have stated, getting a flat response is more about the room than the design of the sub. The way to get a sub flat in room to +/- 3db is with eq from something like BFD.
Have a look into:
* BFD (Behringer Feedback Destroyer)
* room modes
Simon,
As Tim said, you can just put the plate amp right on the back. I dont know about fees from importing from Parts Express because I order all my stuff from www.creativesound.ca in BC. You can also order supplies from www.solen.ca and www.rawacoustics.ca.
As Paul said, you might want to take a look at getting a BFD. You dont need it right away but after you build the sub you should measure the in room response and if needed add a BFD.
As Tim said, you can just put the plate amp right on the back. I dont know about fees from importing from Parts Express because I order all my stuff from www.creativesound.ca in BC. You can also order supplies from www.solen.ca and www.rawacoustics.ca.
As Paul said, you might want to take a look at getting a BFD. You dont need it right away but after you build the sub you should measure the in room response and if needed add a BFD.
Another option is the Tempest horn (you did say it can be big). Very low distortion and high output. For the 30% of the time you use it for HT, you could eq the bottom end to get it flat to 20 Hz. At about 25Hz with room gain it is probably about 95 db efficient. If you did build a horn, BFD would then be mandatory (but you would probably need it to get the bass sounding like it should anyway).
Tempest horn:
Anechoic response:
Tempest horn
or find it at http://www.adireaudio.com/
Tempest horn:
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Anechoic response:
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Tempest horn
or find it at http://www.adireaudio.com/
Thank you very much guys.
If you have experiences with these amps, I would like to know if the rumble filter hinder performance at very low frequencies?
I'm looking at the PartsExpress website and they have 250W amplifier for 119$ USD.
Will I hear alot of distortions since it's a Class AB?
I know talking about amps is off-topic here, but no one in solid state answered my questions
but you guys answer fast! 😉
If you have experiences with these amps, I would like to know if the rumble filter hinder performance at very low frequencies?
I'm looking at the PartsExpress website and they have 250W amplifier for 119$ USD.
Will I hear alot of distortions since it's a Class AB?
I know talking about amps is off-topic here, but no one in solid state answered my questions
but you guys answer fast! 😉
The rumble filter should only affect sub-sonics and at low frequencies AB amps are fine. I'm surprised to see that PE doesn't have the plate amps with the 24db XO anymore, at least I didn't see it. Too bad. 🙁
The distortion from the driver will be higher by far than the worst of amps. You can easily get less than 0.1% distortion or 1% at worst in a PA amp but 36% THD from the sub total is not uncommon at all below 40 Hz. In other words, don't worry. Class AB amps are not high distortion at all. The lowest distortion amps you can get, as far as I know, are class A.
Actually I used to think this as well until recently. If you have a play with WinISD pro and try a 20 Hz rumble filter you will find that you lose a bit of extension. If you model your specific amp and driver you can then decide how low you need to set it to prevent overexcursion at low frequencies. In some cases you might prefer to set it at 15 Hz as you won't lose extension and will still control excursion sufficiently.
Yeah, that's exactly what I was thinking, I want to be able to go to 15 Hz flat if I can. Does someone knows at which frequency these amps have their rumble filter set?
If I email these companies, will they answer this question?
Is it easy to modify the rumble filter to my tastes? Or that might break the whole amplifier design since the amp is built for it?
Thanks again!
If I email these companies, will they answer this question?
Is it easy to modify the rumble filter to my tastes? Or that might break the whole amplifier design since the amp is built for it?
Thanks again!
simon5 said:
If parts express ships by USPS then you will be charged 14% plus 5$. If its by UPS, then who knows, it can be 50% to 100% in duties and taxes.
For plate amps in canada, http://www.creativesound.ca has some. The cheapest is probably not enough for you though.
Rumble filter I believe takes out the stuff that say 10hz or less, so just really really deep bass.
In my experience UPS charges $50 Canadian just for the customs clearance; duty and taxes are on top of that. So, buying from Creativesound will likely be a better deal. Also, isn't there Q Components for speaker stuff, somewhere in Quebec? I used to get catalogs from them.
I think used pro amps are better value than plate amps. You should be able to pick up something that does at least 400 w/ch into 4 ohms for $300 to $400 Canadian (is it still called a Canadian dollar in Quebec?). Try music stores, sound companies, pawn shops. Also watch out for used home amps, like NAD, Carver, Adcom, Bryston.
I think used pro amps are better value than plate amps. You should be able to pick up something that does at least 400 w/ch into 4 ohms for $300 to $400 Canadian (is it still called a Canadian dollar in Quebec?). Try music stores, sound companies, pawn shops. Also watch out for used home amps, like NAD, Carver, Adcom, Bryston.
Creativesound got a amp that is cheap but weak and the next one is too expensive...
For 400$ Canadian I can get a new 500W plate amp from partsexpress...
If it's really 5$ with USPS I think that will be the path I will follow.
Remember that my goal is to beat a PB10-ISD for less money.
I may end up with a Shiva (125$), 4 inch port (21$) 250W plate amp (119$) with a Adire EBS alignment (143 liters) that will take 1 sheet of 4x8 of wood, so flat to around 18 Hz ±1 dB in-room corner loaded.
I would like it if we could buy a good 250W plate amp for cheap in Canada...
For 400$ Canadian I can get a new 500W plate amp from partsexpress...
If it's really 5$ with USPS I think that will be the path I will follow.
Remember that my goal is to beat a PB10-ISD for less money.
I may end up with a Shiva (125$), 4 inch port (21$) 250W plate amp (119$) with a Adire EBS alignment (143 liters) that will take 1 sheet of 4x8 of wood, so flat to around 18 Hz ±1 dB in-room corner loaded.
I would like it if we could buy a good 250W plate amp for cheap in Canada...
Hi again everyone, I have limited time to build all of this, so I'm worrying a bit about the T/S parameters.
Does the listed specs by Adire are tight enough to not measure them? I mean, will I get ugly peaks and dips because the speaker is not exactly what they list in my vented application?
I could easily measure them, but I would need to break-in the driver. How much time does it takes to break in the driver so that the T/S parameters will be stable enough?
Thanks again!
Does the listed specs by Adire are tight enough to not measure them? I mean, will I get ugly peaks and dips because the speaker is not exactly what they list in my vented application?
I could easily measure them, but I would need to break-in the driver. How much time does it takes to break in the driver so that the T/S parameters will be stable enough?
Thanks again!
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