Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

New complete stereo install on 2008 RLXI


Recommended Posts

Hey all! Its pretty much boating season now and I really need to get a stereo installed. I'm looking for advice on what to do and I'll try to shape up the conversation the best I can.

The boat: 2008 RLXI that had NO stereo installed from the factory. No speakers, no head unit, etc. 

What I want to install: 4 cabin speakers, an amp to power the cabin speakers, and something to feed music to the amp. At this time I do NOT want to install a sub. I don't have a tower so tower speakers aren't needed also.

I have been doing a lot of reading in the stereo section and have learned a lot of great information. It sure seems like the best speakers are either Wetsounds or Exile. Because I am not looking for the best stereo on the lake, I'm hoping to save some money and not go with the top of the line for all components. Here are two speaker sets I have been looking at. I'm leaning towards the Polk's as I have heard them talked about on here a few times and most people seem to think they are pretty good speakers. Are there others that I should look at in a similar price point that may offer better sound quality??

Polk MM651UM in a 4 pack:


Kicker BKM604B in a 4 pack:


The next question that I have very minimal experience is: What amplifier would be recommended to power only the 4 cabin speakers?? Again, not looking for the best possible most expensive setup. Something middle of the road to upper middle of the road. Really looking for specific recommended models here as I don't know squat about amps. 

Also, what to use to feed music to the amp? I have looked into the ZLD from Exile, but think it may be overkill when I only have cabin speakers. I have been leaning towards the Digital Media Center from Exile as of lately, as it seems ultra simple and quite cheap. It also seems like I should be able to mount it relatively easy in the area in front of the throttle lever or possibly above the throttle lever. I think there is enough depth there for the DMC. Are there other good options? Mounting is my main concern with most things I have looked at. I'm open to ideas here and would love to see pictures of how you have done this! Here is a link to the DMC: http://exileaudio.com/store/index.php/install-accessories/bluetooth/exmc1.html

Lastly, is speaker location. Because my boat didn't come from the factory with speakers, the 4 holes for speakers are upholstered over. No bid deal to cut through and install the speakers in the stock locations. My question is, is the dash area the best place for front speakers? I thought in a few years newer of RLIX, they mounted the front speakers in the cubby holes of the walkthrough area. Is this a better location than the dash?? I assume to do this I would need to buy the cubby hole plastic that was meant to have a speaker in it? For the rear speakers, it seems like a no brainer to put them where factory did.

What else am I missing here?? I have read a lot about how to power the HU and Amp, all directly from the battery. Is it necessary to have a second battery? It doesn't seem like it would be for my setup.

Thanks in advance for all of your knowledge and expertise!!!! It is greatly appreciated!!!


Link to comment

Hey Kevin,

Surprised you haven't gotten a million suggestions yet...

I have the Polk MM651UM speakers and love them!  That is a good price.  Mounting the side seat back speakers should be easy (use a fine tooth saw so as to not crack the plastic), but you'll have to take the windshield off for the dash speakers.  Watch the vertical clearance.  The better 6.5 speakers are deeper than the cheap ones.  Some of the gurus will likely chime in but I think the dash location is better than the cubby because they're at ear level and separated a bit.  The walkway cubbies are close together and the speakers would be pointed at each other.

As far as amps, the Rockford and Kicker class D amps are good values, true to their specs, and energy efficient (less battery drain).  I have two of the RF R600-4D amps and the 651UMs can handle the power.  One amp for 4 in boats and one amp for the rear speakers and sub (bridged).

Those DMCs look really nice.  I would have one if I did not already have the armrest head unit.  I still play an occasional CD and do not want Blue Tooth.  Everyone wants too sync up and that gets to be a cluster...  If you go the DMC route leave room on your dash for 3 zone controllers.  You'll want them when you add a sub and tower or rear speakers!

You'll need a second battery if you do much floating with the tunes on.  Many ways to set this up but I like the simplicity of an ACR.  Set it up and forget about it.  No Perko switches. 

If you search this site there are many issues and solutions and ways to tune your system.  Plan the wiring so you do it all at one time: Dedicated hot and ground from battery to every audio component (not through main buss); At least 3 RCA sets from the control area (helm) to where the amps are located; big enough wire from batteries to amps; etc.


Link to comment

That is a good price on the polks and I've run them too and really liked them, BUT with a sub.  With no sub they really put out minimal bass tones.  

If you could fit 8s (kicker, rockford, JL, and wetsounds all have 8" coaxials) you'd be much happier if you are for sure never-ever on the sub.

I ran the polks on a JL XD 400/4 and was very happy with it.  I think you could even get away with 2 full range channels for the polks, running them in parallel (so 2 speakers per channel) which would let you go with an XD 200/2 or XD 500/3.  The 500/3 is basically the 200/2 plus a 300/1 sub amp built into a very small chassis (same as xd 400/4).  For a modest system with four full range speakers and a small sub, the XD500/3 would be fabulous. (link to refub here: http://creativeaudio.net/jl-audio-refurbished-xd500-3-3-ch-class-d-full-range-amplifier-500-w/)

Link to comment

I see that there are no holes, so no, the dash is not the best spot and I would skip it in favor of a better location thats close to the helm area. In this case, a 2chnl amp could be used, or a 4 chnl amp, leaving room for a small woofer later. 

Im all for dual battery banks in a boat and I like the Blue Sea ACR, however, I would consider using in conjunction with the proper switch, which is not a perko. So yes, ACR and no perko, but rather ACR and Blue Sea Duel Circuit Plus switch. Advantages are:

Able to use the house bank for emergency start

Combine the banks to override ACR if the house bank is deeply depleted.

Allow for all loads to be disconnected from the batteries when the boat is in layup. Even when amps are off, they would still have voltage into the power supply. 

The Kicker BKM604 is an OEM only speaker version of the KM604. I would up your budget and consider the KM654. .75" dome tweeter on the 654 over the 604's .5". Size typically matters, even with tweeters. These would a more fair comparison to the Polk UM than the Kicker 604

Link to comment

Hey Guys!

Thanks for all of the great responses and feedback. I'll try to add a little more direction and what I'm thinking at this point, as well as more questions.

For now, because its already ski season and I put my slalom course in last night, I'm going to rule out adding a second battery for the time being. 90% of my boat use to to ski so there isn't a ton of float time listening to loud music.

I'm not opposed to adding a sub, but I think that will be a future stage of this project. I looked through some of the discussions where people made a new kickpanel and put a sub in it and really like that idea, I'm just concerned that it will eat up a ton of time when I should be skiing. It could easily become a winter project.

In terms of speaker locations, I need to clarify another thing. The boat didn't come with speakers from the factory, as I mentioned. The plastic structure of the dash, glovebox, and rear side panels all have holes in them, but they upholstered over the holes so they are not visible. So to install speakers into the factory holes would be very easy, just cut out the upholstery covering them and pop the speaker in place. I realize that the windshield would need to come off to install front speakers, but that's okay because my windshield needs to come off anyway to re-seal it to the boat. Much of the foam adhesive tape that holds the windshield to the deck has come loose over its 1120 hours of use. I'm assuming that you can't easily fit 8 inch speakers into the factory dash locations??

If I don't put front speakers in the dash, and don't buy the cubby hole walkway mounts for speakers, where else have people place the front speakers?? At first glance, this feels like it would add a fair amount of work, but I'm always open to ideas. Pictures are always great!!!

For the factory rear locations, is there enough depth to mount 8 inch speakers there?? On Amazon, Kicker 8" coaxial speaker pair, with LED lights, for $145. http://www.amazon.com/Kicker-41KM84LCW-Coaxial-Marine-Speakers/dp/B00L2SO87U/ref=pd_sim_107_3?ie=UTF8&dpID=511dnDeR2AL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=1T4P85KTE36TT5EAR6BM

The KM654 that MLA suggested as a comparable to the Polks are also right at $150 per pair.http://www.amazon.com/Kicker-KM654LCW-41KM654LCW-Speaker-Lighting/dp/B00KGBQ14W?ie=UTF8&keywords=KM654&qid=1462368324&ref_=sr_1_1&sr=8-1

So here is what I'm thinking, please poke holes.

Use a Exile DMC to hook up to phone or Ipod. Possibly use the "dual zone volume controller" to I could tune the front pair from the rear, if you think its needed.

Buy two 6.5" KM654 speakers and mount them in the front dash areas

Buy two 8" Kicker speakers, assuming they can be mounted into the factory rear locations. (Having to oversize the hole doesn't bother me if it needed, as long as depth is okay)

Buy RF Prime 600 Watt Class D 4 channel Amplifier. $210 on amazon. I should be able to put the full 100W RMS per speaker to the 8" and then dial down the 6.5's to something closer to their 65W RMS rating. I would wire one speaker to each channel, correct??

What are your thoughts on this? What am I missing? Suggestions for something different??

Thanks again guys!

Link to comment

Sorry for the long posts. I'll try to limit to a single question to see if I can get more responses.

Has anyone mounted 8" speakers to the factory rear speaker location in a RLXI?? It seems like there should be enough room, and I will measure before ordering anything, but thought I'd ask first. If I can do this, I think I'll get two 8" speakers for the rear and two 6.5" speakers for the front. Thoughts on this??

Link to comment
Just now, shawndoggy said:

I'd personally rather have the 8s feeding the captain if that's possible, but if not then your proposal seems sound.

They can't be installed in the dash can they?? I'm not worried about making the opening bigger, just wanting to know if they would hit the windshield or bottom out against the deck.

Or where are other places to mount them that look decent??

Link to comment

yeah man I'm unfamiliar with your boat.  Probably 6.5s are the only reasonable choice if factory mounting is on the dash.  

If they do go on the dash, definitely get a 4 channel amp.  The windshield reflects the sound at you and sorta makes those speakers seem louder, so you may want to "undergain" those dash channels to balance with the rear speakers.

Link to comment

Would it be okay to put 6.5" in dash and 8" in rear cabin area?? Then use a 4 channel amp so I can adjust the gain and power to each pair? That's what I'm leaning towards, although I still need to verify my measuring that 8" speakers will work in the rear factory mount location.


Link to comment
8 minutes ago, klinger said:

Would it be okay to put 6.5" in dash and 8" in rear cabin area?? Then use a 4 channel amp so I can adjust the gain and power to each pair? That's what I'm leaning towards, although I still need to verify my measuring that 8" speakers will work in the rear factory mount location.


Yep.  You'll get more bass out of the 8" speakers which will be good if you don't have a sub.  I agree with shawndoggy about setting the dash speakers at a lower gain.

Be sure to measure both diameter and depth of your openings.  You can also use speaker spacers if you need to:


Link to comment

Update: Did some measuring in the boat last night. I think it would be possible to put 8" speakers in the rear of the cabin, but I felt it would add a lot of effort/time to this project that I should have started 5 months ago. So, I'm going to stick with 6.5" speakers.

Here is what I ordered:

Exile Digital media center, Exile dual volume control knob with three sets of RCA cables, PPI P900.4 amp, 4ga NVX amp install kit, 4 Polk MM651UM 6.5" speakers, and 100ft of 14ga oxygen free speaker wire. Now the fun can begin once everything gets here!!!!

I know I'll be limited on bass with just having the four 6.5" speakers. Will most likely add a sub in the off season, although I'm concerned that will be a tough project as I have a 3 outlet heater in front of the kick panel which seems to really eat up the real estate up there. More research needed on what options I will have for a sub when the time comes.

Question: Where is the simplest place to mount a single amp in the storage compartment?? I know a lot of people build a amp board, how is that mounted to the boat itself??

Thanks again for all of your help!!!

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...