Speaker switch?

[ranger481vs]

I have simple 6 speaker set-up on my boat, no amp. Sounds great for my needs, except when anchored and relaxing in the water, I barely hear any music. I'd like to add rear-facing speakers on the back of the boat.

I don't want them on all the time though, if possible. Wondering if I would be able to add something like an A/B switch to toggle between the two bow speakers and the rear-facing. My 4 cabin speakers would be always on. Is there a relatively simple way to do something like this?

 

[alldodge]

Use a single DPDT (Double Pole Double Throw) switch

Select 2 speakers you want to turn OFF when the switch to thrown. Connect return legs on the 2 speakers to the new speakers. Connect main feed to the old speakers to the center contacts on the switch. Connect the speakers so one pair or the other is chosen

Do use the same ohm value speakers, will be labeled on the back

 

[ranger481vs]

Great! Thanks, alldodge.

 

[ranger481vs]

Before I wire things up, I want to confirm if my wiring diagram below is ok or not. I'm not quite sure how I should be dealing with polarity from the head unit and the speakers.

 

[alldodge]

Looks good to me

 

[ranger481vs]

I don’t think my diagram above was right. After non-conclusive research, it appeared as though only the positive wires should be wired to the switch. I combined the 4 negative wires from the 4 speakers with the 2 negative wires from my front left and right channel harness wires. May not have been the best way to do this. 6 wires seems like a lot. See my current wiring diagram below.

Anyhow, I wired everything up, switch works great, got music out of the front speakers correctly and switched to the transom speakers correctly. Then, after few minutes or so of playing, the music would stop (or barely audible) and a high-pitched constant hiss would start.

Any thoughts on how to troubleshoot what's going on? I don't have an amplifier, so maybe my head unit is getting overloaded somehow.

 

[alldodge]

Your first pic showed that the speakers are paralleled so its not a stereo wiring. The next does show stereo wiring.

 

[dingbat]

Amplifiers are very finicky when it comes to loading and grounds.

Tying two amplifiers together through a common ground is a no-no.

How many ohms is the amp rated for?

In series, two 4 ohm speakers becomes 8 ohms…In parallel, two 4 ohm speakers become 2 ohms

Disconnect everything to see if the amp shutdown on over temp from the overload. If it doesn’t, you blew it up.

 

[ranger481vs]

Thanks. I don’t have an amplifier, just the head unit and 6 speakers. Then, added the transom speakers and the switch

 

[dingbat]

Thanks. I don’t have an amplifier, just the head unit and 6 speakers. Then, added the transom speakers and the switch

You don’t have a separate amp…How do you think the “head” unit powers the speakers?

 

[ranger481vs]

You don’t have a separate amp…How do you think the “head” unit powers the speakers?

Sorry, my experience with stereo wiring is relatively basic and not up to speed on proper terminology. What I meant is that I don't have a separate amplifier that the speakers are connected to. They are powered by the head unit only. I didn't understand the comment about two amplifiers though, so that's why I was confused.

Update: I separated the right and left channel negative wires, and testing to see if that was my error. So far, so good.

 

[sam am I]

So radio/head units are just usually 4 channels (Left Front, Right Front, Left Rear and Right Rear) + Sub L & R for the 5th and 6th........Not sure other than the sub L & R's would there be some other isolated 5th and 6th channels? Maybe surrounds?

So most likely the Bow speakers have to be..........
1) Wired in parallel with the fronts (or rears)
2) Wired in series with the fronts (or rears)

Then.....

Usually (50% of time, perhaps older less powerful), Radio/Head Units(including "head units" that can ALSO drive speakers directly apart from their high Z RCA jack outputs), ALL the speakers signals returns are all common (although have separate wires) with one another, this 100% can be checked/verified with a few simple ohm meter measurements between all the sig returns wires.

**AND** are all ALSO common with the radio/head unit's battery negative.

So, in case of #1 above and having common sig returns, the stock config should look as follows.....



To then add stern speakers and to also mute the bow speaker at same time...



But in case of #2 above that the bow's are in series, then the stock config should look as follows.....



To then add stern speakers and to also mute the bow speaker at same time...



BUT, in the case of SEPARATED sig returns (including this just purchased) AND again, in case #1 above, the stock config should look as follows.....



To then add stern speakers and to also mute the bow speaker at same time...



However in case of #2 above that the bow's are in series AND again, in the case of SEPARATED sig returns, then the stock config should look as follows.....



To then add stern speakers and to also mute the bow speaker at same time...




**This is because unlike the mega wattage amps, the typical radio/head units DON'T have an internal DC-DC step up power supply that magnetically(transformer) create a additional secondary ISOLATED SIGNAL return(speaker minus).

 

[sam am I]

Revisions to drawing #6 and #8 above, no need for 4PDT switch, a DPDT can be used by just opening one leg (+ or -) of the un-energized speakers circuit path, it will work just as well with less.........

Separate returns and wired in parallel and adding stern speakers...


Or separate returns and wired in series and adding stern speakers...

 

[KD4UPL]

The negative from the left and right should not be hooked together. That's likely your problem.