First time sub

[Adrien]

Hey guys, I'm just getting into HT stuff but I always try to DIY in all of my hobbies. Looks like a good place to start in this one is a Sub. I've done a bit of lurking around and I just wanted to run my first little project by the rest of you.

Pretty simple really...I plan on using this driver:

http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=295-545&DID=7&raid=46&rak=295-545

With this amp:

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=300-802

And then building a down firing sealed enclosure per the Manufacturer's Specs.

Anybody see a problem with this?

One more thing, the total cost will probably be around $150. Will this DIY sub (assuming I build it properly) outperform a pre-made brand name sub in the same price range?

Thanks!

Adrien

[Inu_Yasha]

Honestly I would go with a metal woofer for protection and longevity. It's up to you though in the end. For a little more you could get this and it ships free:

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=293-280

[jonathanb3478]

Or, what about these (price in USD):

http://www.mach5audio.com/product_info.php?currency=USD&products_id=42&osCsid=887d93091fb3496b1746bb82ee6d6e14

Even adding the appropriate CAD number below to one of those, they make sense to me for your situation:

http://64.141.109.88/pictures/other/canada-post-shipping.html

Good luck with whatever you decide!

[Adrien]

Thanks for both recomendations.

It would appear that I should consider a different woofer, but the amp I've chosen is suitable?

Thanks,

Adrien

[SJetski]

Anybody see a problem with this?

One more thing, the total cost will probably be around $150. Will this DIY sub (assuming I build it properly) outperform a pre-made brand name sub in the same price range?

HI all, long time lurker but first time poster here.

OP i'm going to focus on these points i quote above. Apparently you're looking for a sub that'll sound as good, or better than a commercially made sub. But that driver doesn't seem to offer a key ingredient or two to make that happen, one major aspect is that it's frequency extension only goes as low as 36hz as per the description, meaning it won't play those grumbly lows contained in movie soundtracks. You may well know that it's hard finding an 8" driver that sounds like a 10" or 12" but i've been researching the topic lately and have stumbled across these little gems.

1) The MCM 55-2421 which weighs 8 1/2 pounds actually.

2) The Elemental Designs 9Kv.2 which i stumbled upon in this avs thread.

The MCM driver has apparently been around for years already and gets good feedback when used with smaller or some alternate designs. The 9Kv.2 driver would probably have the edge in most cases but it is also triple the price, i figured i'd list it for research and reference purposes. Personally i had been researching the topic because i was looking to replace the woofer in a small sony SA-WM250 8" sub that i picked up brand new for a song ($50 for a small enclosure + 100w plate amp was too hard to pass up imho). Was going to modify it by reinforcing the box structure internally and externally, line it with polyfill and eventually replace the driver with something more capable.

Those are some ideas for a small 8" sub, but otherwise like most everyone else here, i would sooner recommend a sub based around a 10" or 12" or 15" driver which will likely yield more favorable results. But yes, that amp looks more than capable for a smaller design.

Good luck either way

[Adrien]

There's a couple reasons I was going for a 8 inch. One is my application, 95% of the time this will be used for music listening in a very small room where I didn't want an overwhelming amount of bass, nor a very large enclosure due to space constrictions. Two, since it is my 'first' DIY HT project, I figured I should start small.

Once I move from my current location and purchase my TV and what not, I'll probably build a large sub that fits that application.

Thanks for the suggestions, that MCM looks like a solid choice.

Adrien

[ThomasW]

There's a couple reasons I was going for a 8 inch. One is my application, 95% of the time this will be used for music listening in a very small room where I didn't want an overwhelming amount of bass, nor a very large enclosure due to space constrictions.

You can always turn a bigger driver's output down.

Why don't you post the max box size you can live with and we'll go from there...

[cobbpa]

2) The Elemental Designs 9Kv.2 which i stumbled upon in this avs thread.

I've used an eD sub for my HT sub; it's not bad, but from what I read, poly cones are less than ideal. If you're looking around their site, check out the eu-700 too--you may be able to use a couple of those. I wish they still sold the A series...I had one of those in my car once...best looking sub I've ever seen. They have a new slim 10 that may fit in a small box.

Regardless, just saying I've used the company with some success, but others have advised to avoid poly cones; I'm not a very well-trained ear and my kv.2 does an accetpable job for me.

[ThomasW]

Poly cones are okay, they simply aren't very stiff.

It's a trade-off, the ED has a poly cone, better motor and longer throw. The Quatro has a stiffer cone, shorter throw and not that great a motor.

If someone really wants an 8" sub, the Tang Band W8-740C PE Part Number 264-854 is a good choice

[Owen Bartley]

I'm actually getting very interested in that MCM. I remember reading about it before and thinking about it, but now I'm really itching to build something, and since I can't afford to build anything that will outclass my Tempest, I might do a small project and give/sell it to someone. I'll be following this thread closely to see what you decide to do. (Bonus points if the driver is readily available in Canada)

[Brian Bunge]

Skip the MCM and go for the Tang Band if you must use an 8" driver. From what I remember, the MCM's don't hold up well over time. I believe the issue had something to do with the spider giving out, but don't remember for sure.

I've built a few subs with the TB and it has worked great when a small driver was needed. It has strong output down to about 30Hz. You can pretty much forget about anything below that.

[mrogowski]

If I may add...

100 watts of power is not a heck of a lot for a sub. Not sure if cost is an issue but consider getting a bigger one. The reasons are twofold:
- You will always use/need the extra headroom
- You did mention that this was your first stab at things, so if you see yourself growing, you would at least not have to ditch the amp because it is too small

Best regards,
Mark

[Adrien]

I don't have an exact size for the enclosure that I have to stay under, I had just assumed if I went with an 8" driver I could keep it down to a small package.

After comparing the two, that TB does looks like a pretty nice driver.

For the amp size, I'd like to stick with something for this application. If/when I do build a larger sub(s) in the future for a full blown HT, I'll probably by new sub equipment anyway and keep the 8" i'm planning on building in-tact for another setup.

Thanks for input guys, this is a good community with friendly people.

Adrien

[cobbpa]

You know...what the OP really needs is the Elemental Designs 8ax they made a limited production of a few years ago. I don't have specifics or t/s parameters handy, but I remember it was 20+mm xmax one way & could handle 1,000 watts. No joke, it's a real 8" driver with the good looking nomex/carbon fiber cone.



Ha. It was obviously for car use, putting those capabilities into such a small package. Every now & then they are posted for sale on the company's forum, but they're getting pretty rare.

[ThomasW]

I don't have an exact size for the enclosure that I have to stay under, I had just assumed if I went with an 8" driver I could keep it down to a small package.

The question was asked to get rough idea as to what size box you wanted to live with...

[Inu_Yasha]

You know...what the OP really needs is the Elemental Designs 8ax they made a limited production of a few years ago. I don't have specifics or t/s parameters handy, but I remember it was 20+mm xmax one way & could handle 1,000 watts. No joke, it's a real 8" driver with the good looking nomex/carbon fiber cone.



Ha. It was obviously for car use, putting those capabilities into such a small package. Every now & then they are posted for sale on the company's forum, but they're getting pretty rare.

I personally have an ed sub as my car sub and I have to say it is a boomy sub. If you're looking for something cheap then yeah, go for it, but if you're looking for something musical, look elsewhere.

From what OP is saying, he/she is looking for something to compliment music. First and foremost, as Thomas said, what are your constraints size and price wise. Also, will you possibly be using this in a HT environment later on? If so, I would wholeheartedly suggest going with at least a 12. Believe me, going from an 8" to a 12" made a MASSIVE difference in sound. Same thing when going from a SPL type sub to a musical sub. Just weigh your options.

[Adrien]

The size of my sub was basically just going to be the driver's manufacturer specs for a sealed enclosure. This sub is going to be under my desk as this stereo i'm building is going to be used for music whilst on my computer. Occasionally I play my 360 (but really it's just a fancy widget that takes up space) and I might get a Oppo DVD player to watch Dvd's on my monitor. When I do build a full blown HT with an LCD TV and a surround system I plan on building a large sub or two for that, and keeping this sub for the computer.

Thanks,

Adrien

[mrogowski]

The size of my sub was basically just going to be the driver's manufacturer specs for a sealed enclosure. This sub is going to be under my desk as this stereo i'm building is going to be used for music whilst on my computer. Occasionally I play my 360 (but really it's just a fancy widget that takes up space) and I might get a Oppo DVD player to watch Dvd's on my monitor. When I do build a full blown HT with an LCD TV and a surround system I plan on building a large sub or two for that, and keeping this sub for the computer.

Thanks,

Adrien

Ahh.... Now we're getting somewhere.

The Dayton 8" and the 100 watt amp will be more than enough for what you're after. Good value for the buck spent.

Best,
Mark

[SJetski]

Poly cones are okay, they simply aren't very stiff.

It's a trade-off, the ED has a poly cone, better motor and longer throw. The Quatro has a stiffer cone, shorter throw and not that great a motor.

If someone really wants an 8" sub, the Tang Band W8-740C PE Part Number 264-854 is a good choice

Yep, that's a pretty capable looking little woofer. I guess the best choice depends on what size/type of enclosure they'll be using, ported, sealed etc etc.

Skip the MCM and go for the Tang Band if you must use an 8" driver. From what I remember, the MCM's don't hold up well over time. I believe the issue had something to do with the spider giving out, but don't remember for sure.

If true then the one good thing about it is the driver's low cost, which somewhat offsets it's questionable lifespan. Wonder if it has anything to do with the setups these drivers were popular with (those fitzmaurice horns, high wattage perhaps ???)

Pretty intrigued by some of these little powerhouses, This thread has quickly become the one-stop-shop for 8" subs :B. Sorry if i'm threadjacking or veering off-topic.

- Steve

[Adrien]

No apology needed as far as i'm concerned Steve. I'm glad this thread turned into what it did. I've got a lot of good information frome these guys and hopefully this thread will help somebody else in the future.

Adrien

[Adrien]

I've decided to use the W8-740C and I'm having trouble figuring out the right size for a sealed enclosure. I downloaded WinISD and tried to figure it out for myself, but I didn't have all the parameters required...probably due to me not knowing how to read the datasheet properly. I've found a few posts that seemed to hint to around a .55 or so, but i'm just not sure.

Thanks!

Adrien

[Inu_Yasha]

Vas: .81 cu. ft. or basically a box that is .81 ft^3 is what the speaker's specs show. I would actually try to build something like this:

https://www.htguide.com/forum/showpost.php?p=229129&postcount=6

considering someone used a driver much like what you are planning and got good results.