Thinking about adding an amplifier to the radio

[jrings]

So i am sitting here at work thinking about my boat on a dreary Wednesday morning in Cincinnati Ohio. The one thing I would like to possibly change about my new-to-me 2400SR is that I can't hear the radio very easily when under way. I am considering adding an amplifier to the existing radio. I really don't know what all is involved other than in my younger days i installed an amp in my car and it seemed pretty straight forward. I believe I need a 4 channel amp since I have 4 speaker to amplify. I don't need a super expensive amp but something decent... can anyone chime in on suggestions?

Joe

[shrew]

Do you anchor much and for any length of time? IMHO an amp chews through a lot of amp hours in the battery bank, no pun intended. I agree I can't hear the radio well when I'm underway either.

[seapuppy]

well..that has been one of my main beefs about Bayliner/maxum's for yrs....and yrs...they put the damned radio at your knees ...so..I got one of these things..they work great....mount it away from the compass....but beleive me..they are worth the 40 bucks..

http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=467555&catalogId=10001&langId=-1&storeId=11151&storeNum=50157&subdeptNum=50158&classNum=50163


they hook up to the back of your vhf radio and usually there are 2 wires in the back to connect too...some radio's have a jack back there...get the 4.5 size speaker..

SP

[ss3964spd]

Joe, get behind the helm and look at the back of your existing head unit. See if there are any RCA jacks hanging off the rear of the unit.

If there are then adding an amp should be fairly easy. The RCA's provide the line level input to the amp. Then all you need is 12V, Ground, and a trigger from the head unit to turn the amp on when the radio is turned on. The trigger wire is usually blue or orange I think. Then you just re-wire the speaker wires to the amp's outputs.

If you don't have RCA's coming out of the back of the head unit adding an amp isn't as easy. Smartest thing to do at that point is to replace the head unit with one that does not have a built in internal amp but supports an external amp. Or, a new head unit that does have a built in amp with a higher output rating than your current head unit.

Dan

[seapuppy]

oops...I was thinking about the VHF....never mind my post above.......



SP

[oneradride]

There is plenty of room in the sides of the boat for some nice 6.5 two ways. Please see picture. I also Run dual batteries.. before I go any further, if you are running high end audio they are almost a must.
I also have a DB digital mono sub amp and 2 cobalt 10's in a custom box in the ski locker (under the back seat) that are dual ported through the front that can been seen at 4:03 in my video.

http://www.youtube.com/watch?v=6-rsGxgQCg4

If you don't already have RCA outs on your head unit there is a thing called a line output converter and it'll work just fine. Not bragging, just trying to give you some ideas. I did professional audio and video installation for about 7 years.... it was a long time ago though :)

http://i974.photobucket.com/albums/ae226/oneradride/boat-Aquaholic034.jpg

[oneradride]

Wanted to add.. "IF" you go this route and decide to add some speakers in a better location.... with the hole saw.... gently get the pilot bit through and reverse the drill!!!! Go through the fabric and insulation in reverse. When you reach the wood/fiberglass switch it to forward again. :)

[jrings]

I know this is a little old but I am still trying to figure out what would be my best option. It seems that we have some people that are much more knowledgeable about amps etc than I am so I thought I would throw out this link to what seems to be a decent amp. Perhaps those that know about these things could chime in...

http://www.techronics.com/caraudio_11310_JBL-Marine-MA6004-320W-RMS-4-Channel-Marine-Amplifier.html?aff=72182

Just to let you know my intention is to add volume without distorting the sound at cruising speeds. I am by no means looking to compete in "loudest and most obnoxious boat" contests but simply a little louder radio...

[ss3964spd]

Joe,

Did you check out your existing unit as I suggested above? IMO you need to know what you have first.....

But to answer you question the amp you linked to seems fine. You will need to know what your current speaker specs are though.

Dan

[jrings]

Joe,

Did you check out your existing unit as I suggested above? IMO you need to know what you have first.....

But to answer you question the amp you linked to seems fine. You will need to know what your current speaker specs are though.

Dan

SOrry, I did check and it has the rca plugs but only 2. should it have 4? My current head unit is a Clarion M275...

[oneradride]

Two is fine if you are going to run a 2 channel AMP.. The one in your link is a 4 channel....
They make affordable "y" splitters that will allow you to utilize all 4 channels of the amp HOWEVER if you use them you will only have front to rear fade OR side to side depending on how you plug them in.

http://www.cablestogo.com/product_list.asp?cat_id=2009

By the way.. I love this stuff.. if you have questions please ask away :)
No one is posting because its cold almost everywhere..... Glad you are!

[jrings]

Okay, few more for you...
I would like to amplify 4 channels. Is my only option with my current unit to do as you suggested above with the y splitter? If I go that route will I be able to utilize all 4 channels of the amp, or would it only be using 2 channels? If I got a new head unit would it come with 4 rca jacks? My current head units specs says the peak output is 50w x 4 channels. Am I correct that adding the amp I have linked (rated for 60w x 4) would boost the per speaker output to 110w per speaker? Basically adding the wattage from the head unit and the amp together? Or... am i an idiot?

[oneradride]

You are not an idiot at all, these are often misconceptions.

There are 2 different outputs on the head unit. The RCA's are considered LINE LEVEL and this is what you want to go to the amp.... This allows the amp to do the work it was intended for. Line level signal is CLEAN (low power) and that's what you want. The other high powered wires are for the head units internal amps and they are usually overrated, inaccurate garbage. These are typically not used at all when an external amp is introduced.

(Unless you are using a line output converter) which essentially strips all the head unit power away and you are left with line level signal anyway.

So to answer your questions:
1. I would like to amplify 4 channels. Is my only option with my current unit to do as you suggested above with the y splitter? If I go that route will I be able to utilize all 4 channels of the amp, or would it only be using 2 channels?
Answer: Yes you will have to split the signal to use all 4 channels to/from the amp. If you desperately want fade AND balance you can use a line output converter on 2 of the head unit powered channels to accomplish this.

2. If I got a new head unit would it come with 4 rca jacks?
Answer: Some do, some don't... it should say in the specifications.

3. Am I correct that adding the amp I have linked (rated for 60w x 4) would boost the per speaker output to 110w per speaker? Basically adding the wattage from the head unit and the amp together? Or... am i an idiot?

Answer: No.. please see above :) 2 completely different signals.


You also have more options... but I'm not sure you want to go there.. I'm talking about running your speakers in series or parallel. Often used for running multiple speakers on one channel. Then you introduce the challenge of ohms and not dropping them too low in parallel.
Let me know what you buy and I'll send you a wiring diagram on exactly how to hook it up. I'm that bored :)

[mcoffey]

Nope, sorry but it does not work that way. Your stereo has a built in amp that can deliver 50wx4 (though many overstate these numbers considerably). if using an external AMP, you must provide line level to it, that is what the RCA outputs are for. They are called pre-amp outputs. Your head unit only supports 2 channel pre-amp out so you will have to replace it with a unit that supports 4 channel pre-amp out or use splitters as already suggested. There are no issues with the splitter method, you will just have left and right only (or front and back) with 2 speakers on each channel. This is not Dolby Surround Sound here so I doubt you will notice any difference at all with 4 channel or split 2 channel.

Now there are some affordable head units that do support 4 channel pre-amp out. I just installed one in mine last summer so can't attest to reliability yet but it seems like a decent unit (I am not using an AMP though). It has 4 RCA out on it and it is configurable to be Front and Sub or Front and Rear (I think that is how it works).

It is the Sony CDX-M30 and states this on Crutchfield:
•outputs: two sets of preamp outputs with selectable rear/subwoofer output

There is a Clarion that claims to be 4 channel but it seems 1 is only for a sub so that is no good for you.
That is the M109 and states this:
•outputs: 4-channel preamp outputs ( 2-volt front, sub nonfading)

You will definitely get better sound out of an external 50W amp as opposed to a head unit that claims to be 50Wx4.
You do need to check your speakers though and make sure they can handle wjhat you will be pushing to them (Watts and Ohms).

Whatever you do, do NOT connect more than 1 speaker to each channel on the AMP. That cuts your ohms in half which will cause something to fail (either speakers or amp) and the sound will not be as good).
So 1 speaker only to each speaker out on amp and eitehr drive the amp with the 2 RCA and a splitter or replace head unit with 4 channel model.

Hope this helps :)

[mcoffey]

Arrrggghhh, too slow again :(

[jrings]

http://www.crutchfield.com/p_105KDBTP50/JVC-CD-Receiver-Bluetooth-Adapter-Package.html

I know this isn't marine grade but price and options seem nice. What do you guys think? It also says it comes with free installation package but since I am putting it in a boat I assume there will be no wiring harness? Should I just pick some specific make and model of a car instead?

[oneradride]

mcoffey, it's all good!! 2 responses that basically same the same thing adds validity and confidence.

[jrings]

Is there a head unit that puts out enough watts to not require an amp?

[oneradride]

jrings... you might want to start your own thread just not to confuse the two subjects....

In my humble opinion and I know others feel differently... Marine grade is for hard core shrimpers and the like... chances are your stereo is NEVER going to see water or even mist for that matter......I've been building boat audio systems for over 20 years and NEVER have had a normal car stereo fail, not even once.

All new stereos come with an included specific harness. You may have to make it work with your boat, but it will have one. The installation package is typically a kit to make it fit in various vehicles. Assuming you don't have a shafted radio... then you have a DIN, 7 by 2 inches. they will all work and you should need no "kit" because the sleeve that is included will accommodate the new unit.

[jrings]

Started new thread in electronics for the head unit questions...
As far as the amp goes. Since my existing radio has easy access to the back of it and I could easily mount an amp in close proximity to it can I not use the 2 rca jacks and just run the speaker out wires from the radio thru the amp and back to the speakers? this would use all four channels of the amp and I would still have fade and balance right?

By the way, I am not set on the amp that i posted as my only option. If either of you guys has other suggestions that might be a better fit please chime in...

[oneradride]

With the use of 2 line output converters on powered wires, yes. You cannot run powered head unit wires to an amp.
Or use the 2 RCA's and 2 powered wires with one converter for both fade and balance.

[jrings]

With the use of 2 line output converters on powered wires, yes. You cannot run powered head unit wires to an amp.
Or use the 2 RCA's and 2 powered wires with one converter for both fade and balance.

Thanks, that is good to know... As far as specs when looking for a good amp what do I need to pay particular attention to? For example, in my previous posts I included a link for a JBL MA6004. It was rated to 4 x 60watts. I found a PowerAcoustik D4-1000B this morning that is rated for 4 x 80watts. I know there is a lot more I should be looking at other than just wattage right? Below are 2 examples. If you wouldn't mind pointing out the goods and the bads that would be helpful. Thanks again!

http://www.techronics.com/caraudio_15069_PowerAcoustik-D4-1000B-1000W-Max-4-Channel-Class-A-B-Demon-Series.html

http://www.techronics.com/caraudio_11310_JBL-Marine-MA6004-320W-RMS-4-Channel-Marine-Amplifier.html

[ss3964spd]

Actually, in a boat application, wattage is what you're looking for. Let's face it, you won't be doing any critical listening. All you want is good, reasonably clean, sound and pleanty of it.

IMO, to make this a painless as possible, I would change the existing stereo to a "head unit" (head units contain all the electronics but do not contain built in amplifiers like your current unit does). Head units almost always have 2 sets of RCA (line level) jacks. Then pick a 4 channel amp from the same manufacturer to ease the wiring.

You can do Y splitters but you will lose a little signal and therefore may not be able to drive the amp to it's rated output.

Where are the existing speakers located? Location plays an enormous role.

[oneradride]

Get as much amp as you can afford (within reason of course).... if it's too much you can always back off the gain controls. You may want to upgrade your speakers down the road, then you can readjust the gain controls accordingly without having to redo the entire system.

[jrings]

I have 2 more that i am considering. Please give me an opinion on which of the 4 links (2 of the links in the post above) looks like the best bang for my buck...

http://www.amazon.com/MB-Quart-NAU460-4-Channel-Amplifier/dp/B001T9N4WC/ref=sr_1_10?s=car&ie=UTF8&qid=1330617020&sr=1-10

http://www.amazon.com/Kenwood-Kac-8405-Channel-Class-Amplifier/dp/B004XDL21Q/ref=sr_1_1?s=car&ie=UTF8&qid=1330617166&sr=1-1

[GlennW]

Both are quality products and as mentioned you will need more wattage than say in a car cabin. My rule of thumb is to spend more than you want to, in my case double.
You don't want that empty feeling 2 months down the road saying "I wish I had spent more money", been there.
Go a little bit overboard, I have the capabilities of pushing almost 1400 true watts with my system, will I ever use it...most likely not.
If you underpower you will always over heat and have to shut down to reset.
Pay attention to what you buy, class A/B amps are rated at 14.v volts, this is only achieved while the alternator is running or you have caps for reserve installed.
Class D are rated closer to the 12v's that our batteries push out without the electricle support of engines running etc.
Some of the ratings you will see are maxed @ lower ohms such as 2 or 1, which is not a bad thing especially when setting up subs if you choose to bo that route. But make sure the amp is stable for this.
Summer is not quite here yet so sit back, read up a little, set back a few more pennies over the next month or so and you will be much more happy with what you achieve, and who knows I might end up on your Christmas card list :)

[jrings]

UPDATE:
I ended up getting the JBL marine amp MA6004 4 channel amp. I have it mostly installed along with a new head unit. My question for all the audio guru's is that right now I have the amp wired to be turned on with the head unit as the wiring diagram showed (blue remote wire). My question is that I would really like the ability to control whether the amp is on or off instead of having it turn on whenever the radio is on. Reason being that If my family is anchored listening to a Reds game for example I don't necessarily need to have the amp on using up juice. However if I am anchored drinking cocktails with all my buddies and want the radio jamming I do want the amp on. I believe instead of using the remote wire from my radio or head unit I can just use one of my unused accessory toggles on my dash to turn on the amp...?? Is my thinking correct?

[ss3964spd]

Sure, you could use a toggle - assuming it has the amp capacity. Otherwise you'd have to install a relay that is triggered by the toggle.

Question though; if the head unit has no built in amp, or if it does but you're not using it, why would you want to run the head unit and not the amp?

Dan

[mcoffey]

Yeah, I'm kinda with Dan here. I am not even sure if sound will pass through an AMP that is powered off. Remember that the RCA pre-amp outs are line level so even if it does pass something, it will be really, really low. Speakers need some sort or wattage to get anything out of them.

As for the switch though, should work fine. It is all low amp too as it just energizes a relay in the amp, it does not actually power the amp.

[ss3964spd]

It is all low amp too as it just energizes a relay in the amp, it does not actually power the amp.
Good point - could use the toggle to energize the blue wire which will then switch the amp on. Only thing I don't know is if that blue remore on/off wire is 12V or not. You could use a multi meter and check what the voltage is on the blue wire coming out of the head unit when the head is turned on.

No, if you have all your speakers connected to the external amp you won't get any sound from them unless the amp is on.

Dan

[mcoffey]

Maybe a second battery with an isolator would be a better option here? You can then run it all day till she kills the second battery, then just start it up and let the alternator do it's job :)
That or carry around a jump box as a safety net.

I like the isolator route if it were me. here is one (even marine grade) for only $63.00. That plus an extra battery, batter tray and some wiring, you are all set.
http://www.iboats.com/Marine-Battery-Isolator-1-Alternator-2-Batteries-ProMariner/dm/cart_id.227994743--session_id.330337290--view_id.237463

if you are not familar with these, they allow you to connect 2 batteries to the alternator so they can be charged. It isolates them though so draw on one battery cannot pull from the other (it allows voltage to flow 1 direction only, kinda like a diode).
There are also manual battery disconnect switches too but you have to remember to "switch" them :)

[jrings]

wow, this is much more complicated than I thought... Just to clarify I already have 2 batteries and a manual switch so I already have a little safety factor so I won't strand myself by killing the batteries. Maybe one but not both... Good point about the low level stuff, all this may be a mute point if no sound passes thru the amp if it is off... Perhaps I will give it a shot this weekend.

[ss3964spd]

J,

I can tell you that no sound will pass through - not even a whisper, if you have the speakers wired to the external amp and it isn't turned on.

Dan

[jrings]

J,

I can tell you that no sound will pass through - not even a whisper, if you have the speakers wired to the external amp and it isn't turned on.

Dan

ok. sounds like I don't even need to try... Thanks. I will just leave it like it is. As the saying goes, if it ain't broke, don't fix it... Thanks again for all the expertise.

[jrings]

Finally got it installed.

[ss3964spd]

Sweet.

Pleased with the results?

[jrings]

Sweet.

Pleased with the results?

Not real sure yet but initially yes. I am still trying to figure out how you are supposed to adjust the crossover or gain screws...

[Warpa1]

Unless running a multiple speaker system those adjustments wont do a lot, They are more for fully active systems, one amp for tweeters, one for midrange, one for bass and a few for subsonic if i remember correctly from my car audio build days. The crossover scres will just cut off certain frequencied to certain speakers (stops you pumping full range inc bass thru tweeters and blowing them) The gain just increases the output soarce like the volume controll without distorting it....but with a full range speaker setup you wont benefit from any of that.
If you do have a full range setup then many appologies as i have not read the whole thread:shocked: Will read it now lol

[oneradride]

Looks like a real nice install.. only one thing I might change.. Your ground wire (at least from the picture) looks to be insufficient, especially considering the length.. probably 5 or more feet to the negative source. Typically want to use the same gauge as the power and I always use one of those star washers to make SURE it really digs in.

http://www.randyray.com/TMC/images/RFShield/StarWasher.jpg

[jrings]

Looks like a real nice install.. only one thing I might change.. Your ground wire (at least from the picture) looks to be insufficient, especially considering the length.. probably 5 or more feet to the negative source. Typically want to use the same gauge as the power and I always use one of those star washers to make SURE it really digs in.



I will change that, thanks for the tip!