Advice on free air sub replacement for Lexus LS430.

[Nico Yazawa]

Hi all! New to the forum and am hoping you guys/girls can steer me in the right direction.

So it has probably been half a decade at least since I've really done much with car audio other than installing a few head units so I've pretty much forgotten everything I used to know. I'm hoping to get a little advice on what to do.

I recently purchased a 2004 Lexus LS430 with the Mark Levinson premium sound and navigation. It has a subwoofer in the rear deck which unfortunately is partially blown and sounds really rattly. When I push down slightly on the sub, it sounds fine but I can't see any tears in it or anything. Anyway, I just want to replace it.

I figured I would use this as an opportunity to upgrade a bit but I plan for it to be temporary. I want to replace it with a nice system later this year. I am not ready to upgrade my headunit yet as I will be doing a custom Android tablet with a DAC install. That is a summer job when the weather is nice. So I will be using the factory head unit for now.

So I'm looking at buying a free air sub so I can just drop it in the deck. I will be using an aftermarket amp for it though.

I have an old school Alpine 3555 sitting around that I would like to use to get some extra bump. I was able to find these specs on online:

Maximum Power Output........................................500w total

Power Output (2020 Hz to 20KHz, at 14.4v battery voltage)

4 channel mode: 50W x 4 (into 4 ohm with 0.08% THD) or

75W x 4 (into 2 ohm with 0.3% THD)

3 Channel mode: 50w x 2 + 150w x 1 (with 0.3% THD)

2 channel mode: 150W x 2 (into 4 ohm with 0.3% THD)

Fequency Response.......................................... ....10 Hz to 50 KHz

Signal to Noise Ratio............................................ 105dBA

Slew Factor............................................ ................ Greater than 5

Input Sensitivity .................................................. ... 100 mV to 2V

Input Impedence......................................... ........... 10 K ohms Min.

Power Requirement....................................... ....... 11-16V DC Neg Ground

I'm thinking about buying the Kicker Comp S 40CWS84 8". I can drop this right into my rear deck but I also have the option of putting it in a box later. I can get it for like $60 on Amazon. Here is the thing though, I'm hesitant about buying such a cheap sub as I used to spend a lot more on subs... Do you guys think this will be decent enough to hold me over six months or so? I really don't want to spend over $100 on the sub as like I said, it is temporary. I'd buy something higher end used but I want to get this going quickly so I don't want to deal with trying to get a deal going. The older model, the Kicker CWCS84 CompC, is also available. I would assume the newer one is a bit better but the old one is a Prime item so I can get it here fast.

I was also looking at a Pioneer TS-SW2002D2. It is a little more at around $70 on Amazon. I have no experience with Pioneer subs though. I'm not sure what to expect. This is a Prime item too which means I can get this thing here very quickly.

I listen to a lot of pop and electronic music. Lot's of J-pop, EDM, trap, vaporwave, trance and other electronic based music. So I think something tight will be a good option. I'll probably go with a 10" down the road for a better middle ground between tight and deep bass though.

I already purchased the speaker line to RCA converter so getting sound to the amp will be no problem but I'd like some individual control for the sub. The amp has no remote for adjusting the bass. What would you guys recommend to accomplish this?

Any advice would be much appreciated. I haven't done anything car audio related for so long, I feel like I've forgotten everything I ever knew. So I feel like a total noob right now lol.

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[kr15 5,000+ posts]

Generally, free air drivers will be high QTS models. I consider .9 and higher to meet this criteria.

Id guess if you scowered Parts Express you could find a driver that suits you

 

[Boomin_tahoe 5,000+ posts]

Wow. That's a very old amp....

 

[Boomin_tahoe 5,000+ posts]

I actually have info and a pic of that amp...

 

[Nico Yazawa]

Generally, free air drivers will be high QTS models. I consider .9 and higher to meet this criteria.
Id guess if you scowered Parts Express you could find a driver that suits you

The Pioneer has a QTS of .98 and the Kicker is like .54 or something. So maybe I'm not understanding QTS but isn't a low QTS better for a sealed enclosure and has better efficiency but a high QTS is better for free air because the sub relies on itself for mechanical support? So the Pioneer may be the better option here for free air but should I want to put the sub in a box later, the Kicker would probably be best?

Wow. That's a very old amp....

Hehe, yeah. Thank you very much for those pics. Now I can confirm the specs. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Also, any idea what I could do for a remote bass control since the amp doesn't have one?

 

[Boomin_tahoe 5,000+ posts]

The Pioneer has a QTS of .98 and the Kicker is like .54 or something. So maybe I'm not understanding QTS but isn't a low QTS better for a sealed enclosure and has better efficiency but a high QTS is better for free air because the sub relies on itself for mechanical support? So the Pioneer may be the better option here for free air but should I want to put the sub in a box later, the Kicker would probably be best?


Hehe, yeah. Thank you very much for those pics. Now I can confirm the specs. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Also, any idea what I could do for a remote bass control since the amp doesn't have one?

Don't think that amp has that capability. You can take a look on the side of the amp if it has a telephone looking port.

 

[kr15 5,000+ posts]

Low qts drivers prefer ported.

At .98, it is a very good option for free air. Down the line, if you wanted to put it in a box, it would need a sealed box. A ported box for a driver with that type of Qts would need to be very large.

 

[Nico Yazawa]

Don't think that amp has that capability. You can take a look on the side of the amp if it has a telephone looking port.

Yeah, there is no remote plugin thing but since I'm using the factory headunit for now, not having one is kind of a big deal since I won't have independent sub control.

I was thinking of using something like this: https://www.walmart.com/ip/PAC-LC-1-Bass-Knob-Universal-Remote-Level-Control-with-Female-RCA-Interconnect/21550475?wmlspartner=wlpa&selectedSellerId=5254&adid=22222222227015594858&wl0=&wl1=g&wl2=c&wl3=40838701112&wl4=aud-310687321802la-78652110752&wl5=9019274&wl6=&wl7=&wl8=&wl9=pla&wl10=114435154&wl11=online&wl12=21550475&wl13=&veh=sem

That's probably my best bet, huh? But the thing is, since I'm using the speaker to RCA converter, I'm really only getting whatever bass level I have the entirety of my speakers set at from the factory headunit. So I'm limited to whatever the max level of that is, correct? So really, it is going to limit just how much base I can get. So am I going to need to actually get an EQ if I want to crank the bass?

EDIT: Uh, I just realized. Those don't actually adjust the bass do they? They just adjust the gain, correct?

Low qts drivers prefer ported.
At .98, it is a very good option for free air. Down the line, if you wanted to put it in a box, it would need a sealed box. A ported box for a driver with that type of Qts would need to be very large.

That's what I was thinking, thanks! I think I'll go with the Pioneer for now. Worse case scenario is I have to put up with a mediocre sub until later this year when I do a proper system. I may not even put this in a box anyway since I'll probably step up to a couple 10" subs in a proper enclosure later. Besides, the sub is only $72 on Amazon so it isn't the end of the world if I waste my money on it. Plus, I'm sure it will sound far better than my blow sub

 

[pickup1 5,000+ posts]

What I did in my accord with the premium sound...was found a dual 4 polk audio 12 in a small box....unplugged the 8 in the rear deck and hooked the 12 to the factory amp...it works and don't sound too bad..for now...until I put my 2-15s in there amd run the amps I got.

 

[Jcsaudio]

Although I have not tried them myself, I hear nothing but good things about JBL sub offers. They can also be used in free air/open baffle. I especially hear good things about their series 3 sub offers.

https://www.crutchfield.com/p_109STAGE81/JBL-Stage-810.html?tp=68848customer-reviews-tab

This looks good too https://www.crutchfield.com/p_108KAPPA8/Infinity-Kappa-800W.html?tp=111

 

[Nico Yazawa]

I went ahead and ordered the Pioneer. I think it will work okay until later this year. I bought a remote RCA gain adjuster as well to give me some form of control over the sub. I have a nice little compartment in the center dash that pops out, that I can put it in to keep it concealed when not in use. Apparently you can completely disassemble the unit as well, so you can mount it in the dash flush but I probably won't do that as it will look out of place.

I sure hope my amp works. This is a 2 ohm DVC sub so I'm planning to feed it 150 RMS from my amp (maybe more as I bet this thing is underrated). But if the amp doesn't work, it isn't like I can just power it off the factory setup as the current system expects a 2 ohm sub. I could have bought something that would run at 2 ohm but then if I ran it off the amp, I could only get like 75 RMS. So I sure hope I don't have to go out and buy an amp but if I do, I'll end up feeding this thing a bit more power lol.