I have a chunky 8” JBL sub in my IMVE with sub filter that came with it, it didn’t sound much better than really cheap subs that I use. I added kicker 4” backbox speakers that was a big improvement and easily added. Normally use decent 3 ohm JBL’s in parallel but they need a spacer.

Never been happy with the in cabinet subs although adding a better speaker helps so added a 15” external sub that I had spare, makes the cab subs sound crap and insignificant! Can easily be overpowering but once you get the level to your liking it’s all good.
Connected to 4 pins, forget the glass shaking now it’s the room.

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It will not be overwhelming if you adjust it low but the sound will be much more rounded, I just happen to like it going through me as I’ve had sound systems since the 80’s.
Shame they don’t build them like Spooky’s TNA with the cab speaker in a box.

I have hertz kit in my van, amps and speakers. 1kw monoblock amp running a 10” Mille sub, was fitted in 2009 and still going strong
Amazing quality and sound.

I have a 1kw 1 ohm Hertz monoblock amp and a dual coil 2ohm 15” sub, amp runs at 1ohm! (In my vehicle)
Amazing what can be done these days, that has been running fine since I installed it in 2009. Vision goes a bit blurry when cranked up though.

Always been careful with ohms on WPC and SAM, I heard WPC can have issues with lower ohms but not heard anything with SAM so I use 3 ohm JBL’s in series to be safe.

Had to replace a fuse inside my sub yesterday, had the sub nearly 20 years so knew it was an internal fuse.
Wired to 4 SAM pins via Pinovator 5 way and fitted with flipper fidelity, JBL stage 3 427’s and Kicker DS4. JBL’s sound best then Kicker then Flipper Fidelity. Have better subs in all those pins but do not come close to my external lol
Boom boom boom shake the room!

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My Halloween came and the sub sounded terrible, pushed the cone and very tight. Got underneath and could see it was touching the grill and cab.
Put a spacer on and now moving some serious air and flexing the glass, tracking down all the rattles is difficult but at least it’s right now.
Will be connecting up to an external sub then turning it right down until zero rattles. Backbox speakers sound great.

School boy error or can’t be bothered? Latter I think as Rick and Morty had the same issue apparently, shame as it’s a half decent sub and deserves freedom to move!

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