Best 18" woofer for around $350

[Bobby.b.]

I have a 4.75' (after subtracting the port) box and say $300-$400 to spend for an 18. I was just about to order a Lethal Injection 18d2 from ssa and I thought maybe I should get some feedback first.

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[Popwarhomie 5,000+ posts]

I would probably do a Fi SSD 15.

 

[SlugButter]

I have a 4.75' (after subtracting the port) box and say $300-$400 to spend for an 18. I was just about to order a Lethal Injection 18d2 from ssa and I thought maybe I should get some feedback first.

I would not run that Incriminator 18 in 4.25 cubes ported. That’s the volume I would use for a sealed enclosure with that 18. It will want at least 5 cubes ported but preferably even larger than that. if you’re going to run it ported, you’d also want to get the extra options on it, especially the extra spider. If you’re getting a bare bones lethal injection 18, you’ll be better off running it in a sealed enclosure.

 

[Bobby.b.]

Just reviewed the box plans its was 5.65' the port has 43" of area and takes .7' total so its 4.95' net volume tuned to 29hz and theres 6 lbs of poly in it for what its worth. the hole is already cut for an 18 I had a ct tropo cheapy 18 in there that lasted a few months and blew up. At about 800w it did about 112db and peaked at like 43hz from what I recall, could be wrong, in a full size chevy van with no interior. not much cabin gain to speak of a sealed box will not work IMO.

 

[SlugButter]

Just reviewed the box plans its was 5.65' the port has 43" of area and takes .7' total so its 4.95' net volume tuned to 29hz and theres 6 lbs of poly in it for what its worth. the hole is already cut for an 18 I had a ct tropo cheapy 18 in there that lasted a few months and blew up. At about 800w it did about 112db and peaked at like 43hz from what I recall, could be wrong, in a full size chevy van with no interior. not much cabin gain to speak of a sealed box will not work IMO.

That’s way short on port area. The box sounds like an issue to me. The CT sounds tropo 18 in 6 cubes would be a decently loud setup, but port area would need to be closer to 70 sq. inches. The box you have is really small on air space and port area for any 18 I’ve built for.

 

[Bobby.b.]

yea the box is small so is the port but didnt seem like a big deal it models for 20m/s air speed at 1200watts. It never made any noise. I doubt its compressing real world with little to no cabin pressure compared to a car. Incriminator lists the LI18 on their spec page as having a minimum 3.5 sealed or 5 ported.

 

[djdilliodon!]

Even with a loose suspension, 18’s need some volume ported. You would be better off with a 15” sub and more port area as well like slug stated.

 

[Bobby.b.]

If I did go down to a 15, whats the advatage?

 

[deez283 10+ year member]

If I did go down to a 15, whats the advatage?

Having enough airspace.

 

[Bobby.b.]

Having enough airspace.

... so like a little less output and a flatter response? I guess I need a reason better then "not enough airspace"... per the mfg it is enough air space and it models ok on winisd.

 

[djdilliodon!]

If I did go down to a 15, whats the advatage?

You’ll be able to get the full potential from a 15. Of course if you are willing to go bigger on an enclosure you can definitely go 18.

 

[shredder2]

I guess I need a reason better then "not enough airspace"... per the mfg it is enough air space and it models ok on winisd.

1st off I love 18" subs:

Manufacturers typically have a marketing dept that will usually go to great lengths to sell their products.
70-90in2 of port in around 5.5ft3net- 7ft3net usually makes most 18's happy. Dependent on power.
For example, this 1750watt 18 was overpowered a fair bit... and was in 5.6ft3 net with 77in2 of aeroport for a reason. Recommendations claimed 6-7ft3 for this sub on their website. Designed around the power and installed for the vehicle it did numbers like 153db+ garage and 152.4db usaci for 2 years with only a slight coil tap when hitting the lanes.
I think I was close/at the subs ultimate potential... 3K clamped worked with a 1750rms Fi ferrite sub.
It wasn't a burp box either, it was tuned to my musical tastes it went as low as I needed it to and got loud for what it was. It sure flexed and slapped windshield wipers when I needed it to...

To go with under 5ft3 you'd probably need a stronger motor, that means a beast sub with more output potential and THAT means... $. The capable 18's I've seen cost and need power and port to use in the 5ft3 range.
Space makes bass... especially in lower power setups.
As stated... space makes bass
Food for thought

 

[Bobby.b.]

Ok so, say I get rid of the internal port and add an external one Im looking at a 5.65' net box. would be allot easyer then building a new box. whered you get that port from?

 

[SlugButter]

can probably get something similar to those here.

8" Ports

 

[Bobby.b.]

Is the flared end really needed If Its big enough say I just fiberglass a 10" concrete form tube to the box... ugly but that would be cheap and easy.