Connecting House Subwoofers

[xale]

Hi

I bought a caravan with a Sony MEX-N4150BT in it, connected to some outdoor house speakers. Not the latest and greatest I know, but it's what I've got.

I have bought some Sony subwoofers - they are from a home entertainment system. I spliced them into the existing speaker wiring to see if it would work, and it does!

But it's not very 'bassy'. I noticed there are also 4 RCA plugs on the other side which, on reading the manual, seem to be for subs. Can I plug them in here? I've tried, but they don't work.

Not sure if there's s software setting I can't find, or if I need an amp to use the plugs on that side (the others come out of the other side).

Any help and advice would be very much appreciated. Thanks!

[NGY]

5 hours ago, xale said:

... or if I need an amp ...

Yes, you do. Sub outs on head units normally meant for either active subwoofers or subs hooked on a power amplifier. 

You can also see it in the manual (see as well the other RCA audio outs for additional, externally amplified front/rear speakers):

Sub amps require a lot of power, way more than the regular speakers, and normally there is not enough space in a 1 din head unit  for such an amp. Even if it was feasible, as only a fraction of the buyers install subwoofers, it would be an excess feature, with no value to the vast majority of users.

[xale]

Thanks a lot for your reply NGY.

So my suspicion was right - rca's not amplified, hence no sound. 

Something like this do the trick? Maybe even two of them?

 https://www.ebay.com.au/itm/2-1-Channels-400W-Hi-Fi-Auto-Stereo-12V-Car-Audio-Amplifier-MP3-Radio-Booster-T5/193742212125?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D230925%26meid%3Dc02acf726e9549d1b1a07e268bf06529%26pid%3D101195%26rk%3D6%26rkt%3D12%26mehot%3Dco%26sd%3D393143632209%26itm%3D193742212125%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv9PairwiseUnbiasedWeb&_trksid=p2047675.c101195.m1851

 

[NGY]

5 hours ago, xale said:

Something like this do the trick? 

This looks like a neat "all-in-one” amp. Good for those who want "bigger sound" than their head unit can provide. I cannot judge though how good its subwoofer circuit is.

If your main speakers are loud enough with the Sony, and the only thing missing is the good bass, I would rather go for a dedicated sub amp, something like this (or eventually, better).

Beware though, that a few 100 Watts on a 12V car circuit means a few dozens of Amperes (!), therefore it would also call for dedicated, thick enough wiring directly from the car's battery (and/or, actually another, dedicated battery, also with some beefy buffer caps, next to the amp).

[xale]

Thanks so much NGY for your help - legend.