Amp sub connection

[ST2015]

Hi.

I just bought a Rockville RockGhost V2 powered 11" sub for my car. I have a 2015 Ford Focus ST (version with bigger display).
Is there a good video on youtube (or somewhere else) of how to dismantle the front radio to connect the sub? All the videos i saw just somehow "skip" the step bi step dismantling...
And does anyone know if it has a port to diretly connect the sub?

And another one, since I'm already writing...
If I have say a 2 channel amplifier (both 300W RMS @ 2 Ohm). 1 channel for a 200W RMS 2 Ohm sub (most people reccomend amp 50% more powerfull than the speaker; but that's not the issue).
And the second channel for 2 (coaxial) speakers, both 100W RMS @ 4 Ohm. I connect those in parallel to get 2 Ohm (for the amp). Does each speaker now get 150W RMS of power (+50% per speaker; ideal), or does each speaker get 300W RMS power?? Again, lots of videos about series and parallel wiring to match the speakers and amp, but none of them says what "happens" with the power output...

Please help. I thank everyone in advance.

Have a nice one...

Click to read more...

 

[1aespinoza 10+ year member]

And does anyone know if it has a port to diretly connect the sub?

To connect a signal to the sub amplifier, you can get it from the speaker locations. Splice into the speaker wires. There is no need to go behind the radio.

Does each speaker now get 150W RMS of power (+50% per speaker; ideal), or does each speaker get 300W RMS power?? Again, lots of videos about series and parallel wiring to match the speakers and amp, but none of them says what "happens" with the power output...

The power is divided. An amp can only put what it's circuits have to offer. So it will be 300w RMS divided into the number of speakers.
On another note; some amplifiers are designed to play stereo AND mono at the same time. Check your manual to see if your amp can do that.
Edit: you can match RMS speakers to RMS amplifier power. No need to go 50% or higher.

 

[ST2015]

Ok so the power is divided in parallel connection: 2 speakers 100W RMS each @ 4 Ohm (conected in parallel to get 2 Ohms impedance) both receive exactly 100W of power from a 200W RMS @ 2 Ohm amp. Right? Just to confirm.

Judging by your answer I would guess the same happens in series connection:
2 speakers (100W RMS @ 2 Ohm) both receive 100 W of power from an amp that is rated 200W @ 4 Ohm. Right?

But what do you mean with geting a signal from the speaker locations? Just ad another wire (2, + and -)? Where exactly? How to splite? Can you be more specific please.

Again, thank you.

 

[Doxquzme Premium Member]

Need to back this up a bit. Are you considering using another amplifier for another set of speakers?

 

[ST2015]

Need to back this up a bit. Are you considering using another amplifier for another set of speakers?

I'm considering 1 2-channel amp. Both channels 450W RMS @ 2 Ohm.
1st channel for both speakers (each 150W RMS @ 4 Ohm) wired parallel to get them to 2 Ohm. So that both receive 225W RMS.
2nd channel for the 300W RMS @ 2 Ohm subwoofer.
That should work perfectly, considering amp "should" be 50% more powerfull than the speakers. OR??

 

[Doxquzme Premium Member]

Okay, slow down partner!

Before we get into all the parallel and series wiring, ohms and power distribution (what's & watts), need to establish the end game.

You said that you have a Rockville powered sub already, correct?
You intend to use the factory head unit, correct?

With that in mind and the fact that you have already purchased the powered sub, here is where you need to start.

Here are the factory locations.
Front L/R components (6.5"/ 6.75" two way) Front lower door and upper door.

Same as the front (for the most part) but I would use coaxial in the rear and components in the front.

Forget about all that power stuff for now, it's make more sense as you progress.

What is the budget?

 

[ST2015]

1st of all...many thanks for all your answers for now.

@Doxquzme
If you read my first post one more time you will see that I "talk" about 2 different things.
I apologize for the confusion I may have caused.

1) I bought the Rockville selfpowered sub for my Ford Focus. Don't need anything else than a specific info (guide) about connecting it to the stock system in the car (either through radio directly or somehow else).

2) I want to bild my own stand up "party speaker" from "car" components.
I have a radio, the "downgrade" from 230V to 12V also shouldn't be a problem.
The rest from my last post about the 2-channel 450W RMS @ 2 Ohm per channel powered amp is considered for this "party speaker".
But this can "wait".

The sub for the 1) will arrive in two weeks time at latest. That's something I want to get done first and as quickly as possible. If possible.

Anyways, again, many thanks for now...

 

[Doxquzme Premium Member]

Okay, no worries.

I have used a number of setups for home use (see attachment), with car amplifiers, subs mostley (and a 5 way setup in my garage!). The biggest mistake that people make is buying a cheap power supply. The one in this picture is around $136.00 - buy a cheap PS and you end up with a costly POS.

this one is decent enough

PowerMax 100 Amp 12V Power Supply Converter w/LED Light - Returned Lightly Used | eBay

Ideal for use in RV, Automotive, Boat, Car Audio, or any applications where battery charging and/or 12V power is needed. LED Indicator light. PM3 Series Converters can also be wired in Series or Parallel to reach even higher power outputs.

www.ebay.com

Keep in mind the only thing that made this practical was the purchase of the 2K amp at $50, a display unit from a local friends shop. So for around $200 I was able to setup a music room set of subs. There are a boatload of professional amplifiers for around $250-350 that would be much more practical.

Rockville D14 7000w Peak/2000w RMS Class D 2 Channel Power Amplifier Pro/DJ Amp | eBay

Bridged 8 Ohm: 1 x 7000W Max. Bridged 8 Ohm: 1 x 2000W. Item Code: D14. Bridged mode allows you to combine both channels power into one channel for use with a subwoofer. RMS Power Output Power, signal, clipping, and protection LED indicators on front of amp.

www.ebay.com

We can look at that later.

As for the car setup, you don't need to pull the dash. You can usually locate a left and right speaker lead (and yes, use on from each channel) going into the door from each door, tap into that and run it to the L/R hi-level inputs on the amplified sub. Then once installed, set the gains on it like you would with any other setup.

From Rockville

 

[1aespinoza 10+ year member]

both receive exactly 100W of power from a 200W RMS @ 2 Ohm amp. Right? Just to confirm.

Judging by your answer I would guess the same happens in series connection:
2 speakers (100W RMS @ 2 Ohm) both receive 100 W of power from an amp that is rated 200W @ 4 Ohm. Right?

Yes on both of these.

But what do you mean with geting a signal from the speaker locations? Just ad another wire (2, + and -)? Where exactly? How to splite? Can you be more specific please.

Splicing means connecting one wire to another. So one wire to the positive and one to the negative wires or terminals of each speaker. One set on the left and one on the right. Then you run those wires to the subwoofer's amp "high input" harness.
Speaker location will vary by vehicle. I think Doxquzme pointed out those locations. So you will need access to those speakers, which is easier than taking the radio out.