How To: Install aftermarket sub with stock enclosure in non-factory sub 2nd Gen Ex

[tommyarmour]

Peak Power pretty much means what a subwoofer can handle for short periods of time. If you were to install a amp with enough juice to push 600 watt's and were to mess with the gain and push 600watts to the JL you would probably blow it up. The Kenwood could handle it for a short period. That being said anyone with a brain isn't going to do that. But it's good to know deep down my Kenwood would be able to handle a substantial enough wattage increase without any ill effects.

Holy smokes, you know your **** Joe.
******(JOE: Biggest issue I see is the efficiency. The Kenwood is 78db, the JL is say 84db. Issue is, for about every 3db of efficiency, you need double the wattage to provide a given volume. So, in order to play a given volume with the JL, you need, say 100 watts. On the Kenwood, being that it is 6db less efficient, you need at least 400 watts going to it. (Or 300, I think it doubles though)****


db = The higher the number. The more sensitive the speaker. The higher the number the less power the sub needs to get loud.

So with the db of the Kenwood being 78 db's the stock amp putting out 85 RMS (150w MAX), it's not going to be able to do much for the Kenwood sub correct?

I'm not sure about the db's being labeled correctly for the Kenwood amp if that were the case and it required 6 more db's than the JL then essentially it would require a more powerful amp, meaning the description is false. According to the description of the speaker you would look for a amp no larger than 200 watt rms( It would seem by the db's alone you would want something in the range of 300+.

(I think it goes something like 3db's is a moderate change then to double the volume it would be something like 10db's). Maybe that is where they got the 600w peak from?

And of course the lower the Frequency the deeper the bass: I just didn't feel with a 8" sub getting lower than 40hz was even going to sound good. But that is about as far as I go with my education. With that being said I produce my opinions based on trial and error.

I ordered my sub on Saturday, I will get it tomorrow. Maybe I'll put together a little video, and embarrass myself. LOL I have the distinct feeling I am going to have no choice but to upgrade the stock amp based on db's alone. UHG

 

[tommyarmour]

Joe Dirt:

So for the stock amp I definitely chose the wrong sub? The JL with a sensitivity of 84 could be played sufficiently with the stock amp pushing only 85w RMS.

The kenwood with a sensitivity db of 78 will struggle tremendously with a lower wattage amp.

What in the world was I thinking?

So another words I will never be able to outperfom the JL without a 300watt rms amp. And that would only enable the speaker to compete with the JL. And then it would be subjective to the listener of the true winner. Technically the JL would be able to hit lower bass, that is however subjective to the listener as well, because you can only go so low with a 8" sub and keep the volume to a desired level.

Well don't I feel like a dumb ass.

This is how I chose the speaker I chose:

1. Price: was higher(maybe the material's in the sub are more expensive) I assumed this somehow had something to do with the quality being better.
2. Looks: I thought the magnet and housing looked solid and was somehow a better build.
3. Thinking I could really test this speaker with a max peak of 600 watt RMS

Anyway I have to admit at this stage I should have chose the JL. It's a little too late now. I will end up picking up a nice amp and wiring kit. I don't have a choice.

Well Joe, It is what it is thanks for your input and helping me understand these subs a little more clearly.

 

[GRNMACHINE]

Im guessing your sub will still sound good, I dont think Ford was going for any sound contests with the plastic sub box housing. And now for another question for the man we call Ask Joe Dirt.... Do I "piggyback" the "power on" wire from the aftermarket amp with the "power on" blue/white wire from the stock Ford amp to the headunit??

EDIT: piggybacked the wires, now have sub and music. Not much Bass though, turned the gain up to near max. Will work on it again tomorrow nite. Maybe the deck has some sub tuning options, or maybe I need a different amp... (And thanks for the advice on cabling, also found some leftover monster cable, just the right length too.)

 

[Joe Dirt]

On my deck, I have the loudness set to on/high, the gain at about 80%, and the bass set to -2 to 0 on the deck itself to get what I have...

If you're using the remote control for the amp, set the gain to max on the amp and then vary the level from the remote. I had it mounted in my armrest cargo area with some velcro. I also have the bass boost live on the amp. I think the Jensen has a dial for that, try playing with the settings...

 

[tommyarmour]

Hey Joe Dirt hopefully your monitoring the thread. I have my sub out, and just need to know which speaker wire from the amp is positive and which is negative. My choices are black and white from the amp to the factory sub, I just need to cut them and connect them to my new kenwood. Normally I would say the black is negative but the connecter for the black wire is larger and that in door speakers usually tells me its positive for the larger connector. So I need some help.

 

[tommyarmour]

No need for a response I went ahead and just did the logical thing and used black for negative. worked a charm. Kenwood sub fit great I did have to drill new holes they were ever so slightly off. I obviously didnt need the screw that screwed into the magnet of the stock speaker I left that screw out and just a hole there. Doesnt seem to matter too much. The stock amp with my head unit is able to bump this speaker pretty hard. I could get more out of the speaker with a cleaner signal, but why it's only a 8". For an 8" with the right song's this thing hits pretty good.

 

[toypaseo]

Pry won't make such difference, but I would plug/seal that hole left from the magnet screw...

 

[tommyarmour]

Pry won't make such difference, but I would plug/seal that hole left from the magnet screw...

If I ever decide to upgrade the amp I will pick up a short screw to block off the hole.
But until then I am finished. Did the whole job including changing out the rear door speakers for some JL's in less than 2 hours. The right tools and this tutorial really helped.

 

[GRNMACHINE]

Thanks Joe. I ended up getting a Kenwood amp, I really think I should have went with the SoundStorm. I didnt realize it came with a remote to control the levels etc. And I have read thru this post about 1,728 times or so. The Kenwood amp was on sale for $69.99 with $20 off if using paypal thru Crutchfield (they have been AWESOME to deal with-sometimes not the best prices but their customer service is the best). Also installing Dynamat - looked at the peel n seal, definitely cheaper but many reviews complaining about tar smell... I also found the original box you shipped the sub in lastnite and found the thick insulation for the inside of the sub box. Removed the sub, put that in and repacked it with the whole bag of polyfill. For the other poster I drilled another whole for the speaker cable, sub wouldnt sit flush with cable underneath it. Covered both holes with a think stick on felt pad that you would use on the bottom of chairs,etc to not scratch floors. Will test the Kenwood amp again before putting the side panel back on, if it doesnt hit hard I may be springing for the Sound Storm amp. The side panel is not quick or easy to remove to change settings on the amp so the Sound Storm remote sounds very attractive. Thanks again for the writeup Joe, pictures are worth 1000 words etc.

 

[tommyarmour]

Thanks Joe. I ended up getting a Kenwood amp, I really think I should have went with the SoundStorm. I didnt realize it came with a remote to control the levels etc. And I have read thru this post about 1,728 times or so. The Kenwood amp was on sale for $69.99 with $20 off if using paypal thru Crutchfield (they have been AWESOME to deal with-sometimes not the best prices but their customer service is the best). Also installing Dynamat - looked at the peel n seal, definitely cheaper but many reviews complaining about tar smell... I also found the original box you shipped the sub in lastnite and found the thick insulation for the inside of the sub box. Removed the sub, put that in and repacked it with the whole bag of polyfill. For the other poster I drilled another whole for the speaker cable, sub wouldnt sit flush with cable underneath it. Covered both holes with a think stick on felt pad that you would use on the bottom of chairs,etc to not scratch floors. Will test the Kenwood amp again before putting the side panel back on, if it doesnt hit hard I may be springing for the Sound Storm amp. The side panel is not quick or easy to remove to change settings on the amp so the Sound Storm remote sounds very attractive. Thanks again for the writeup Joe, pictures are worth 1000 words etc.

I'm not sure if the sticky felt stuff is going to be able to hold. From my experiences with holes in speaker boxes they have to be plugged and or sealed. That is why I didn't bother trying to just cover mine. I was thinking about plugs down at True Value. Or a short fat screw with a few rubber washers and maybe even drummel something down to fit. I was able to tear my rear panel out pretty fast, but I would be lying if I said I enjoyed it. I would not want to do it every time I had to make a amp adjustment. So I am in your boat on what type of amp to pick up, might just have to have some type of remote. Or I will have to place it under the seat.

Where you the one who bought the JL door speakers? I didn't see much sound different between those and the stock speakers. Was pretty disappointed. The holes lined up fine but there was still a slight gap on both sides of the speaker impossible to get a complete seal in the door with the speakers.

Hey I gotta say one thing, at least we are trying.

 

[Joe Dirt]

Nice work guys! Sorry- I was out of town this weekend...

It was in the PM, but I did say this in there, for reference:

Grab a 1.5 volt battery (any size), touch the positive terminal of the battery to the positive wire going to the speaker, then do the same for the negative wire. Look at the speaker. If the speaker pops out, the polarity is correct. If the speaker pops in, the speaker is hooked up backwards (out of phase). A word of caution here: DO NOT hold the battery power to the speaker for more than a second, or You will damage the speaker if you hold constant power to it.

I think the white was the negative, but I'm not positive. The worst that happens is that it would be out of phase, and you could just swap the wires.

Amazing what a decent sound you can get with one 8" sub, and not have to give up cargo space from hauling around a box. Glad it sounds good!

 

[tommyarmour]

Nice work guys! Sorry- I was out of town this weekend...

It was in the PM, but I did say this in there, for reference:

Grab a 1.5 volt battery (any size), touch the positive terminal of the battery to the positive wire going to the speaker, then do the same for the negative wire. Look at the speaker. If the speaker pops out, the polarity is correct. If the speaker pops in, the speaker is hooked up backwards (out of phase). A word of caution here: DO NOT hold the battery power to the speaker for more than a second, or You will damage the speaker if you hold constant power to it.

I think the white was the negative, but I'm not positive. The worst that happens is that it would be out of phase, and you could just swap the wires.

Amazing what a decent sound you can get with one 8" sub, and not have to give up cargo space from hauling around a box. Glad it sounds good!

OMG I am such an idiot. I looked for about an hour to find the correct wiring configuration for the sub and was unable to find the speaker wiring diagram for the subwoofer. So I opted for "black negative" vs "small and large post". I was unsure due to the fact that usually the negative is the smaller connector and sure enough that is what it was. I was telling a few people about stock wiring is always screwy and they were like come on dude black is always negative and I still doubted it and made a decision to go with black negative. I am bummed now I have to remove everything again today. ****!!!!! Well it will give me a chance to block off the hole in the stock enclosure where the speaker screw was. Any idea's Joe? I was thinking a very short screw with a few rubber washers. What did you use in place of the screw that used to screw into the old stock speaker?


Oh and by the way, I seem to of gotten hooked. I found a 10" jl audio w3v3 sub for 100 bucks. I might just pick it up, and do some modifying. I might be dumping the entire process I just went through for a aftermarket box. I knew better than to start with car audio. I used to be really bad. Turning 43 this month I have slowed down on my impulsivity.

 

[Joe Dirt]

I just duct taped a small circle of plastic I cut out from a chunk of sheet plastic I had laying in the garage, to the inside of the enclosure behind the sub over the hole. Nothing major...

 

[tommyarmour]

Stock amp size for anyone interested in replacing the amp and want to know what the size is of the original amp.

6" 3/4 length(with mounting brackets 8" 1/2), 6 1/4 width, 2" height.


Then if you want the overall size of the space here you go:

 

[tommyarmour]

I went to True Value to find a plug for where the screw screwed into the stock sub. This was a .30 cent rubber plug. 9/16 top.

 

[Joe Dirt]

Nice idea on the plug!

 

[tommyarmour]

Here is a little video to show what the Kenwood does with the stock 85 watt RMS amp.

I didn't have it up too loud, I could of turned the volume up a bit more. The JVC KDA805 head unit that I have I turned the sub up to +8 @ 55hz. Loudness +1, speakers are up to +2.


Youtube video of the Kenwood in action with the stock amp:


http://www.youtube.com/watch?v=bsPsp4h6EFY/YOUTUBE]

 

[tommyarmour]

Nice idea on the plug!

Thanks Joe,

If I had it to do over again, I would put the plug on the inside then there is no way humanely possible the plug could be bumped lose. It's not going to come out the way I have it now, but anything is possible with bass. Did you have a chance to watch the youtube video I made?

 

[Joe Dirt]

I did- that's a nice setup. Hard to tell obviously how it actually sounds, but it sure looks more than capable. If it fits the bill for you, that's 99% of the battle!

 

[toypaseo]

I would put it on the inside, so the pressure does not push it out.

I have not used the OEM enclosures with the magnet screw/bolt. Is that hole threaded?