Cockpit speakers

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Norfolknick

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This may be heresy and thus am apologising upfront!!!

I have just bought a new to me, (thus old) boat which has a rather dead cockpit speaker, which I believe is an extension for the VHF.

Whilst I like the idea of being able to hear the VHF in the cockpit, particularly when sailing short handed, I would like to be able to turn it off, and also double up a replacement to support the stereo such that I can enjoy some tunes - (Hence the heresy, I also appreciate the shear bliss of the silence of the sea, hence the request to turn it off).

Is there a speaker set out there that can support both VHF and the stereo, with some form of switch such that I can also isolate the speaker, switch between modes? Anyone with any ideas, much appreciated!

Thanks
 
Seeing as how noone else has replied here's my 2p's worth....

Can't think of a reason why the feed from your stereo and your VHF cannot be played through the same speaker. In order to switch from one to the other a simple on-off-on switch (suitably located and waterproofed if necessary) should suffice. Switch from the common wire from the stereo to the common wire on the VHF and that should switch both speakers off the stereo and just the one on to the VHF.

I'm sure someone will be along soon to offer different advice. The silence of the sea is fine but so is a little smooth background jazz with your G+T at sundown....

How you hear the VHF with the music on whilst sailing is another matter.....

Good luck.

Chas
 
Norfolknick,

I turn off my cockpit speaker by removing the speaker extension plug in the back of the VHF. The VHF then uses it's internal speaker which I can still hear in the cockpit.

The thing to be careful of that some amplifiers do not like to run open circuit. In other words with no load. So if you use one speaker to be switched from VHF to FM radios, one or other or both may not like it. Plus if the extension speaker plug is still inserted in the VHF when using the FM radio nothing will be heard from the VHF internal speaker.

Also you may wish to listen to FM in stereo requiring two speakers but VHF is in mono needing only one.

My recommendation is to have two separate speakers systems for VHF and FM, each working independantly of their respective radios. This is a more flexible setup.
 
My cockpit speaker has a simple pull switch mounted next to the VHF unit. It interupts one speaker cable and allows me to switch the cockpit speaker on or off. I do not have speakers for my stereo in the cockpit.
 
In general speakers for VHF radio are not good quality sound reproducers so find out impedance for both entertainment and RT radios (often 8 ohms) and get hi fi speaker of your choice to that impedance rather than use a VHF/RT speaker for both.
 
A friend gave me a set of rather nice flush-mount cockpit speakers a while back - I eventually mounted them (British Hunter) in the stern locker†, pointing into the cockpit with a waterproof DPDT switch than can be foot-operated to silence them.

That, and a VHF cockpit mic (Standard Horizon) works for me.

†With some IKEA plastic bowls epoxy'd on to protect the backs, inside the locker - at 1/10th to cost of the kit chandlers sell.
 
A guy from a neighbouring mooring asked to come alongside to compare compass readings because he thought his may have gone wrong. We checked against my main compass and with a hand bearing and his was about 30 degrees out.
When I mentioned the two shiny new speakers on the bulkhead, he very proudly said "yeah, I've just fitted them, great aren't they?"
 
Speaker switching

Radios can generally be paralleled into one speaker without problem. Assuming you are playing at sensible levels. Also generally small radios and amplifiers can be run without a load. So just feed the VHF into one of the speakers along with the stereo to 2 speakers. A simple switch arrangement can turn one or both off by opening the wire. If you are concerned about interaction you can feed both or one via a resistor of about 8 ohms this will make that radio a little softer however. If you are concerned about providing a correct load then use a 8 ohm resistor of higher power rating to switch the o/p to in lieu of speaker. You are pretty safe assuming you need 8 ohm speakers. if the amp needs 4 ohm you will just not get full power. olewill
 
Have you considered that it might be way easier to get a handheld VHF? The hh will get broadcasts so you can hear them, you might have to go to the VHF down below to send a message over longer distances than you could with a hh. Lot less complications. Or get a VHF speaker and stick it into your coaming with an I/O switch.

Good luck.
 
A simple rule of thumb.

Lets take nominal 10w RMS amplifier, stated as that at an 8 ohm load, i.e. the impedance of the speaker you would buy.

If you but a 4 ohm speaker , the speaker would need to be rated to handle 20w RMS.

If you buy a 2 ohm speaker it would need to handle 40w etc...., but the amplifier is unlikely to be very happy for too long, 2 ohm being almost short circuit (read BANG).

The RMS bit is a way of measuring output power. It's an average of the maximum sine wave output (I know, not quite accurate but good enough for this simple explanation). Some cheaper speakers and amps get quoted as 10w (peak) - the wattage RMS of these is roughly 1/3rd.

It's an old trick used by amp salesmen to make the gullible believe they have a powerful amp!

The relevance here is that if the power handling is just quoted as watts, with no reference to peak or RMS then you need to find out which it is.

Another pointer - you can buy two 8 ohm speakers and make the amp see a load of 4 ohms by simply paralleling the speakers, or make the amp see 16 ohms by putting them in series.

As to the comment that some amps don't like an open circuit, I have never come across one.

Put a simple on-off-on switch in your circuit - it will be fine.
 
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Comrade Red said:
A simple rule of thumb.

Lets take nominal 10w RMS amplifier, stated as that at an 8 ohm load, i.e. the impedance of the speaker you would buy.

If you but a 4 ohm speaker , the speaker would need to be rated to handle 20w RMS.

If you buy a 2 ohm speaker it would need to handle 40w etc...., but the amplifier is unlikely to be very happy for too long, 2 ohm being almost short circuit (read BANG).

The RMS bit is a way of measuring output power. It's an average of the maximum sine wave output (I know, not quite accurate but good enough for this simple explanation). Some cheaper speakers and amps get quoted as 10w (peak) - the wattage RMS of these is roughly 1/3rd.

It's an old trick used by amp salesmen to make the gullible believe they have a powerful amp!

The relevance here is that if the power handling is just quoted as watts, with no reference to peak or RMS then you need to find out which it is.

Another pointer - you can buy two 8 ohm speakers and make the amp see a load of 4 ohms by simply paralleling the speakers, or make the amp see 16 ohms by putting them in series.

As to the comment that some amps don't like an open circuit, I have never come across one.

Put a simple on-off-on switch in your circuit - it will be fine.
Click to expand...
I agree with almost everything. At the audio power levels we are talking about and with modern audio output circuitry you can almost do anything you want without blowing things up. Don't get too hung up on the impedance of speakers as the impedences quoted by speaker manufacturers are a bit arbitrary anyway. If you ever saw the measured impedences vs frequency plotted as a graph you would see that '8 ohms impedance' or '4 ohms impedance' is pretty nominal anyway. I am not saying you should disregard and in high power situations it does become very important as the amplifier can be stressed by too low an impedance that is presented to it. However in domestic and car audio you can often completely short out audio stages without blowing them up, but I am not suggesting you make a habit of doing it. Try to avoid turning the volume up to max and shorting it out as that really stresses things. However what I am trying to say is that the average household audio output stages are usually rather more robust than some would have you believe...

To answer the op, you could certainly try just running both devices into the one cockpit speaker, but I wouldn't suggest it as an optimum solution

Our VHF runs into a waterproof cockpit speaker and plugging it in conveniently doesn't cut the speaker on the VHF itself so check if this applies to you.

If you want to listen to music while you are sailing separate cockpit speakers might be the best solution. We have some from Fusion and they sound pretty good. Unless we are motoring, I don't like keeping watch with ear phones in the ears; I lose some sense of the environment - let alone the ability to listen for sound signals!
 
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Oh yes, and BTW, there is nothing wrong with listening to music while sailing or on a mooring. Silence is also golden too.

I often think that coming in full chat into a foreign anchorage with the Ride of the Valkyries playing at 130db shows johnny foreigner you mean business. Of course you can't then cock it all up ;):D
 
Comrade Red said:
A simple rule of thumb.


As to the comment that some amps don't like an open circuit, I have never come across one.

Put a simple on-off-on switch in your circuit - it will be fine.
Click to expand...

Amplifiers which have a transformer in the output get very upset with no load. The back EMF of the transformer reflects back to the transistor or valve as a high voltage. Now this was more of a problem with higher powered valve amplifiers where the output valves were running at near max voltage and any back EMF caused internal arcing. he reason you have not seen one of these is age. Modern transistor output circuits almost universally used do not have a transformer and transistors are probably capable of handling higher voltage if they did. FYI olewill
 
William_H said:
Amplifiers which have a transformer in the output get very upset with no load. The back EMF of the transformer reflects back to the transistor or valve as a high voltage. Now this was more of a problem with higher powered valve amplifiers where the output valves were running at near max voltage and any back EMF caused internal arcing. he reason you have not seen one of these is age. Modern transistor output circuits almost universally used do not have a transformer and transistors are probably capable of handling higher voltage if they did. FYI olewill
Click to expand...

I used to work with some very big amps (kw's) in my early twenty's with professional concert PA systems - never had a problem with no load, but I am fairly certain they did have circuitry built in to protect them from al sorts of catatrophe's including being shorted so maybe they had a few bits and pieces to protect them against no load too. Appreciate the point you make re back EMF though.
 
Are we talking about playing a stereo into a single speaker? If your stereo is fairly recent, you should be able to use the + wire from one channel, and the - wire from the other to get both channels, obviously in mono.

Alternatively, get a pair of speakers, and switch them so they are separate on the stereo, and in parallel on the VHF, thus satisfying the impedance of both.
 
Serious sound

Don't mess around. Put some serious waterproof cockpit speakers in the cockpit sides and Springsteen and the Who will sound great. For VHF, my lazy solution was not a remote wired handset, which I gave away, but an even cheaper vhf with a remote wireless handset.

If all of this sounds antisocial it is as nothing compared with those who use generators to keep their lousy TV sets playing at anchor on the East Coast

PS surfing 500 mies offshore blasting hard rock to the heavens en route to the Azores is not easily forgotten, even if it was a long time ago
 
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