Sub Design

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Ok I am new to all this design stuff, but I am very pumped about the propsect of building a sub for my system. I have been reading and researching and finally landed here on this forum (which, by the way, is very informative).

I currently have a Denon AVR 3805 reciever that I purchased a couple years ago to be the core of the Home Theatre. I am currently using Nuance speakers (which I picked up about 10 years ago from a friend of mine for real cheap) but will be replacing those with Paradigms next year.

Currently using the system about 80% music, 20% movies. That will change next year when I move the system down to the new Home Theare Room I am constructing in the basement (40% music, 60% movies). Room is about 16 ft wide by 14 ft deep and 8 ft ceiling.

I have been looking into components available in Canada. For drivers, Solen in Quebec carries the Peerless XXLS. Creative Sound Solutions in BC carries the Adire line.
I like the 10" Peerless for the idea of a reduced box size with the PR, but the cost goes up (~$270 for both the driver and the pr). The Adire 12" Shiva Classic is only $115. Anyone know of other good drivers available in Canada?

Based upon all this I have a couple of questions hopefully someone can help me with.

1. What is the logical flow for designing a sub? Pick a driver, model it using WinISD, Unibox, etc to determine enclosure parameters, choose amp...

2. Peerless appears to make different versions of the XXLS. One specifically to be used with PR, one for sealed box, etc. Does one perform any better than the other given the right parameters in its correct use?

3. Will the 10" XXLS be able to produce 20Hz that is desired. I keep hearing that 10" just is not enough to get good 20Hz out of. Would the 12" Shiva be better? Which one is better for the size of room.

4. Anything else you can think of that I can't or should be thinking of...


Colin
 
First one must ask thyself....

What budget exists and what space constraints exist?

With those questions answered then you may explore the possibilitys of enclosure types which will be followed by driver and amplifier selection to meet your budget and work well in a reasonably fitting enclosure...

IF you have room for a largish enclosure or the possibility of an IB setup then 15 or 18" woofers are probably the best route... These drivers will give you the most swept output bang for your buck and typically the most bang for your buck elsewhere as well...

If space is very limited(which by reading your first post it sounds like it is) then smaller woofers can be used in PR boxes or sealed enclosures with a linkwitz transform... In this case you will probably be looking at expensive, high excursion, low efficiency drivers with high powerhandling. So you will be spending more money on an amplifier, possibly PRs as well and if not PRs than perhaps a linkwitz transform.

Personally if I were building a dedicated HT room in MY house I'd go for about 4-15" or 2-18" woofers(minimum) in an IB setup. This approach minimizes the space taken up by large woofer cabinets in the room and also allows for less expensive drivers and amplification to be used to get even better results...
 
I failed to mention....

In a largish room, 20hz is pretty unreasonable for a 10" driver to achieve IMO... of course a 10" driver can produce and 20hz wave, it just wont put out enoug SPL to do anything.

I would also say the same for a single 12" driver... In my experience 2-12" drivers seem to be the minimum for getting satisfactory output down to 20hz(even in a ported enclosure). Of course some people might call me crazy
 
Hi Colin,

If I were building a dedicated home theatre in an Edmonton basement, I would look to doing multiple subs in large enclosures distributed around the room. Perhaps as part of furniture (e.g.: seating, tables, speaker stand, etc.) or the wall/floor/ceiling. This way you can minimize nodes and modes. You can't take the room out of the equation.

It is easier to get higher levels at lower freq. if you can do larger boxes. Trying to hit an arbitrary number for bass extension is, I think, an approach that may lead to disappointment. Getting low distortion, well integrated, evenly distributed, and loud and reasonably deep will be much more satisfying.

But, I would think that getting better speakers than the Nuance is a much higher priority. The cabinets are solid enough, but the drivers and crossovers are relatively poor quality (I am very familiar with Nuance - design and company.) In the spirit of DIY, why not re-design the Nuance with higher quality drivers and crossover. Which models do you have?

P.S.: Go Oilers!
 
BassAwdy, space is a consideration. The bigger consideration is the wife factor. She finally sees the need for the sub after watching U2 Vertigo DVD live in Chicago at my Brothers place. But I think I would be sleeping on the couch if I pushed it too far. 4 15' may be pushing it...2x12" or 2x15" may be doable though. What do you mean by IB setup? I am not familiar with this.

Cost is also a consideration based upon the need to upgrade the rest of my speakers. I am thinking around $500 for the amp and the drivers. Psych, I like your way of thinking of rebuilding the Nuances I have. But one project at a time. Have you ever undertaken a project like that before? The sub is enough of a challenge for me right now...I think I may hold off on the rebuilding of the others. If I could save some money by not buying the paradigms, it could go to other component upgrades for the HT including the sub(s).

I have also seen a few posts with Mach5 Audio drivers. Any thoughts on these vs something like the Adire Tempest?
 
Viking552 said:
space is a consideration. The bigger consideration is the wife factor.

A subwoofer is not necessarily necessary :D My personal preference is to build full bass response into the main speakers, end of story. Rear channels are typically run quietly with limited program information so their presence shouldn't upset the tonal balance. If you desire a kick in the bass, you can design it in.
 
IB=Infinite baffle

This approach uses a seperate room or airspace(attic, craw;space, outside, whatever) as the "enclosure." Commonly the minimum airspace considered to warrent the term infinite baffle is some multiple of the VAS of the speaker(7xIIRC but I'd really have to look that up).

This approach eliminates large speakers from the room and puts them somewhere in the walls.

Having even response around the room is a big issue however... For an IB this would mean placing IB woofers at various locations in the walls, floor or ceiling possibly. Otherwise you will probably have some pretty nasty modes and need EQ(and if you are going for multiple listening positions EQ can be impossible to get flat frequency response).

I'll assume you probably arent up for the IB though and ask how big you think you may be able to go on the enclosures... Using the subs as furniture may be a good option as large encloures will be better and they can be more easily 'hidden' as end tables, coffe tables etc... Also as was mentioned before... placing multiple subs around the room in various locations will typically even out a few room modes
 
Hope everyone had a good holiday and welcome to 2007!


Psych, I like the BASH 500W and was considering using it anyway. The price from parts express is awesome. Have you ever ordered from them across the border? I checked and duty is 6.5% on electronics as well as the 6% GST, so it should not be too bad depending upon what the shipping fees are and whether they use UPS or not(brokerage fees).

BassAwdy, thanks for the clarification. The room location does not lend itself well to infinite baffle spaces, so I will stick with boxes.

I am going to try and model the Dayton in WinISD (or WinISD pro?). I see some of the parameters are listed on the parts express website, but I think not all of them are there. I checked the Dayton website and could not find them there, but maybe I was not looking close enough.

My plan is to build one box with a single driver and amp and then add a second box with another driver when the system moves to the new room in about 6 months.


Psych, I need to have discussion with you about the Nuance driver upgrade as my next project.

Colin
 
Hope everyone had a good holiday and welcome to 2007!


Psych, I like the BASH 500W and was considering using it anyway. The price from parts express is awesome. Have you ever ordered from them across the border? I checked and duty is 6.5% on electronics as well as the 6% GST, so it should not be too bad depending upon what the shipping fees are and whether they use UPS or not(brokerage fees).

BassAwdy, thanks for the clarification. The room location does not lend itself well to infinite baffle spaces, so I will stick with boxes.

I am going to try and model the Dayton in WinISD (or WinISD pro?). I see some of the parameters are listed on the parts express website, but I think not all of them are there. I checked the Dayton website and could not find them there, but maybe I was not looking close enough.

My plan is to build one box with a single driver and amp and then add a second box with another driver when the system moves to the new room in about 6 months.


Psych, I need to have discussion with you about the Nuance driver upgrade as my next project.

Colin
 
you need only Vas, fs, and the Q's to model an alignment I believe... Maybe Sd as well, but they should have all of those parameters posted on parts-express... The rest of the parameters winISD 'asks' for when entering in a new driver are for things like max power , maxSPL, cone excursion vs power etc.... You dont actually need parameters like BL, efficiency, etc to get a basic FR simulation.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.