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SSP: add trunk sub, replace shelf woofer, or both?

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JimmyBreeze

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Have been reading through the threads from those who have updated their SSP. Lots of folks seem happy with adding a small powered (via the 12v) sub in the trunk by tapping the signal to the woofer on the rear shelf, though a few have commented that running in parallel takes it from 4 ohms to 2 ohms which causes some 'popping' which I'd like to avoid.

That rear shelf woofer also looks like by far the easier speaker to replace in the car, and since everything's more or less going to be open already to tap it, was wondering if anyone had tried replacing the stock woofer it with a more robust speaker to go along with (or even in lieu of) adding a small sub in the trunk?
 
JimmyBreeze said:
Have been reading through the threads from those who have updated their SSP. Lots of folks seem happy with adding a small powered (via the 12v) sub in the trunk by tapping the signal to the woofer on the rear shelf, though a few have commented that running in parallel takes it from 4 ohms to 2 ohms which causes some 'popping' which I'd like to avoid.

That rear shelf woofer also looks like by far the easier speaker to replace in the car, and since everything's more or less going to be open already to tap it, was wondering if anyone had tried replacing the stock woofer it with a more robust speaker to go along with (or even in lieu of) adding a small sub in the trunk?
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If you're not afraid to cut the wires to the included rear sub, you could just splice into it and just leave the sub unplugged, or still splice the slim sub into the line and put a 2ohm resistor before the existing sub.

Only reason I didn't is because it's a lease and I'm not sure yet if I'm going to keep it or give it back and get something else (maybe a GT).

Though what I really want to do is put a crossover in to take some of the bass out of the original subwoofer since it can't really handle the lower frequencies.
 
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JimmyBreeze said:
Have been reading through the threads from those who have updated their SSP. Lots of folks seem happy with adding a small powered (via the 12v) sub in the trunk by tapping the signal to the woofer on the rear shelf, though a few have commented that running in parallel takes it from 4 ohms to 2 ohms which causes some 'popping' which I'd like to avoid.

That rear shelf woofer also looks like by far the easier speaker to replace in the car, and since everything's more or less going to be open already to tap it, was wondering if anyone had tried replacing the stock woofer it with a more robust speaker to go along with (or even in lieu of) adding a small sub in the trunk?
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You’re only tapping signal, it won’t change the ohm load
 
doubletwist said:
My electronics knowledge is admittedly rusty but I'm pretty sure if you put speakers in parallel it decreases the impedance.
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Adding a powered sub does not add a speaker it ads an amp and functions like a hi-low converter if you don’t use one.

An unpowered speaker would reduce the impedance yes.
 
socktucker said:
Adding a powered sub does not add a speaker it ads an amp and functions like a hi-low converter if you don’t use one.

An unpowered speaker would reduce the impedance yes.
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I think it still counts as an additional load in parallel thus reducing the total impedance, though I could be wrong. I haven't measured it but the built in sub does seem to distort far more easily than it did before I added the powered sub.
 
doubletwist said:
I think it still counts as an additional load in parallel thus reducing the total impedance, though I could be wrong. I haven't measured it but the built in sub does seem to distort far more easily than it did before I added the powered sub.
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This is correct. The formula is z = z1 * z2 / (z1 + z2).

Roughly, a 1x additional load in parallel results in 50% lower impedance, 0.1x is 9% lower, and 0.01x is 1% lower.

What is the input impedance of the powered subwoofer? The higher it is, the better.
 
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Saksak said:
This is correct. The formula is z = z1 * z2 / (z1 + z2).

Roughly, a 1x additional load in parallel results in 50% lower impedance, 0.1x is 9% lower, and 0.01x is 1% lower.

What is the input impedance of the powered subwoofer? The higher it is, the better.
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It's a Kicker HS10 which I believe is also 4ohm for the speaker itself, but I'm unclear on what the impedance is with the built in amp.
 
doubletwist said:
It's a Kicker HS10 which I believe is also 4ohm for the speaker itself, but I'm unclear on what the impedance is with the built in amp.
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The specs say that it has the FIT+ technology which has no load resistor, so the additional input impedance will be negligible with very minimal additional current draw. In fact, it’s designed to be used in parallel with an existing speaker. If not, it would need a special load resistor.
 
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All good points, which brings me back to my original question- would we get better sound simply removing the stock woofer from the equation? Either by unplugging it or, more drastically, physically removing it to add a better pass-thru for the sound?

Or, am I overthinking this and there's an easy way to make both work? The clipping/distortion is what I'm looking to avoid here. How bad it is @doubletwist?
 
JimmyBreeze said:
All good points, which brings me back to my original question- would we get better sound simply removing the stock woofer from the equation? Either by unplugging it or, more drastically, physically removing it to add a better pass-thru for the sound?

Or, am I overthinking this and there's an easy way to make both work? The clipping/distortion is what I'm looking to avoid here. How bad it is @doubletwist?
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Honestly with the added sub just clipped into the existing sub, the only time there's a problem is if I have the stereo cranked, and even then, the speaker doesn't clip, but certain frequencies can trigger quite the rattle in the car. Again only when I have it really cranked. I had some luck with a good equalizer app on my phone (I usually use Bluetooth or AA) to reduce the levels at those frequencies. But you shouldn't actually need that if you don't really crank it.

Over all it sounds a million times better than it did before even leaving the stock sub active.
 
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doubletwist said:
Sorry that was a typo you're correct. It does NOT distort any more than previously.
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Nothing wrong with a typo when it means good news! Sub it is then- would you do the Kicker again?

Was looking at @ZRAT's Rockford Fosgate 10" P300 install alongside an AudioControl LC2i to counteract any bass drop-off the factory tune might add in to compensate for the non-subwoofer in the trunk, though @Ludicrous put in the 12" version and said it fit.

Will update the thread with decision/results once the car (finally) gets here next week.
 
JimmyBreeze said:
Nothing wrong with a typo when it means good news! Sub it is then- would you do the Kicker again?

Was looking at @ZRAT's Rockford Fosgate 10" P300 install alongside an AudioControl LC2i to counteract any bass drop-off the factory tune might add in to compensate for the non-subwoofer in the trunk, though @Ludicrous put in the 12" version and said it fit.

Will update the thread with decision/results once the car (finally) gets here next week.
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Yeah I have no issues with the Kicker at all. All the difficulty I had was a result of trying to do things without cutting any wires.
 
socktucker said:
I saw someone trying to use alligator clips on sub terminals. Not robust!
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That's what I did. 🤔

At least for the audio connection to the original sub. The rest is a combination of crimp connections and pigtail adapters held together with electrical tape. So still pretty janky.
 
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