Getting the most out of 2017 242X E-series stock stereo

[Osric]

First off, I know very little about amps and speakers, so I'm going off of what I can find on this site. I could really use confirmation of my questions, inline below in bold.

@Julian posted this diagram of the wiring problem with the wetsounds bar and the cabin speakers:

View attachment 66140​

It seems to me that if I don't want to add a new amp, another alternative is to wire the sound bar in parallel with the speakers, making a 2Ω load instead of the expected 4Ω or the silly series 8Ω load. Basic electronics would suggest to me that this could draw twice as much power out of the amp as it expects to deliver, which could kill the amp. But ... looking at the Polk D5000.5 owners manual:

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This seems to show that if we're not bridging the power (and we're not, because the RL/RR speakers run to the 8Ω load of the wired-in-series speakers shown above, and the FL/FR wires run to the bow speakers) we can go down to a 2Ω load. And since a 2Ω load will draw 4x more power, of which the sound bar gets half, simply wiring the speakers in parallel without introducing a new amp should double the wattage (and 1.25x the sound output) from the wetsounds bar ... right?

Second, notice that the subwoofer minimum resistance is 1Ω. So this WetSounds 2Ω subwoofer should have twice the bass on a power basis alone, and on top of that be better than the polk sub included because it's actually designed for open air, right? Also, is it the correct size to be a drop in replacement? But I forgot, I'm not supposed to be buying speakers ...

Thanks for all responses/education,

Osric

 

[Osric]

Really hoping for any response! Tell me I'm an idiot, I like it

Osric

 

[BigAbe75]

I think @jcyamaharider may be your guy. I heard he just discovered additional unused wattage somehow. Can’t wait to hear it.

 

[Osric]

So today I did step one which was to set the gain correctly.

On my boat the 4000.4 is wired to the tower speakers and the rear swim platform and the 5000.5 is wired to the main cabin and sound bar in series and the bow speakers. Fading to rear fades to the tower cans and swim platform.

For the system to play correctly as wired both amps have to be set to stereo mode. The gain setting that is correct for stereo is higher than for 4ch so set that switch first.

Then I hooked up my oscilloscope directly to each amp and adjusted the volume to 100% to verify that the head unit never clips and it is good.

Then I adjusted the gain on each speaker to maximum without clipping the signal. Adding the HPF and setting it so that 40hz was unaffected cleared up a tiny bit of noise at the peaks of the 40hz test tone.

Now there is a small problem. Even wired to the exact same input rca plug, the 4000.4 amp is out of phase with the input signal. With the hpf on the signal shifts slightly so it isn’t exactly out of phase. The 5000.5 doesn’t exhibit either of these symptoms. I’d love to hear from someone who knows audio how big a problem this is in practice.

Next step will be to wire the sound bar in parallel with the tower measuring dB of output before and after. I’d like to head out boarding as is first to see how big a difference just getting the gain and filtering right made since subjectively it seems much louder.

Osric

 

[Osric]

A quick outing on the wakeboard confirms that the music is now much easier to hear, but my wife finds the cabin volume way too high when driving. Set to 95%, I can hear it on the board but she'd want it quieter ... so wiring the tower+wetsounds in parallel and putting them both on the 4000.4 seems like the next step for sure.

 

[jcyamaharider]

Add a wetsounds 420. It will be one of the best moves you ever did.

 

[Rod5]

I think @jcyamaharider may be your guy. I heard he just discovered additional unused wattage somehow. Can’t wait to hear it.

The unused wattage is on the sub output of the 5005.1. Stock configuration is a 4 ohm sub pulling 200 watts on the sub channel, however the amp is rated to output 400 watt at a 2 ohm load and 500 watts at a 1 ohm load. So adding another 4 ohm sub in parallel gives you a 2 ohm load and an additional 200 watts for the cost of a sub. When I did mine the ear perception was more than double the Bass just by adding a 2nd sub.

 

[Rod5]

Here is my old thread on this...

https://jetboaters.net/threads/242x-stereo-how-to-exploit-free-unused-watts.13256/

 

[jcyamaharider]

No

the unused wattage is switching the amps from stereo to 4 channel. I was running my tower and transom speakers on one 4000.4 and running it in stero for one rca cable set. I switched to a y cable and another set of rca cables and the volume increased massively with no clipping.

 

[Osric]

the unused wattage is switching the amps from stereo to 4 channel. I was running my tower and transom speakers on one 4000.4 and running it in stero for one rca cable set. I switched to a y cable and another set of rca cables and the volume increased massively with no clipping.

So I had this same thought, because I noticed that the volume had a big jump when switching to 4 channel, but I thought it was just the gain setting changing. I'll have to try the y cables after all, and see if I can get more power out that way.

The wetsounds equalizer looks good but for the moment I am trying to come up with the simplest reconfiguration of what's there that gets max performance.

I want to rewire the speakers and see how that goes, but we decided to do it by building an adapter to do the relevant changes rather than cutting existing wires. I now need to source the connector to build the adapter...

Meanwhile, I just shorted out the cabin speakers. This makes the sound bar loud enough to be heard easily from the wakeboard.

Osric

 

[Rod5]

No

the unused wattage is switching the amps from stereo to 4 channel. I was running my tower and transom speakers on one 4000.4 and running it in stero for one rca cable set. I switched to a y cable and another set of rca cables and the volume increased massively with no clipping.

Hum I kind of remember stumbling on to that too when I reworked my system but figured it was more of gain control adjustment. Not sure switching to 4 Chan mode is really tapping unused watts but maybe so.

 

[jcyamaharider]

Hum I kind of remember stumbling on to that too when I reworked my system but figured it was more of gain control adjustment. Not sure switching to 4 Chan mode is really tapping unused watts but maybe so.

I didnt change the gain because i had that set for the clipping point and the those speakers got noticeably louder.

 

[Osric]

I didnt change the gain because i had that set for the clipping point and the those speakers got noticeably louder.

If you didn't change the gain then you may be clipping now. On my scope, when I set the gain in stereo mode then switch to 4-channel, the signal clips, because the gain dial suddenly means something different to the amp. When I adjust the gain to max that won't clip the signal in stereo mode, it's the same output signal as I get if I switch to 4 channel mode adn then have to reduce the gain to remove the clipping. This is, however, without the Y adapters connected, so I have yet to prove that it really makes no difference.

The adapters are ordered and I can post screenshots of the oscilloscope once I have them installed for testing.

 

[jcyamaharider]

If you didn't change the gain then you may be clipping now. On my scope, when I set the gain in stereo mode then switch to 4-channel, the signal clips, because the gain dial suddenly means something different to the amp. When I adjust the gain to max that won't clip the signal in stereo mode, it's the same output signal as I get if I switch to 4 channel mode adn then have to reduce the gain to remove the clipping. This is, however, without the Y adapters connected, so I have yet to prove that it really makes no difference.

The adapters are ordered and I can post screenshots of the oscilloscope once I have them installed for testing.

I will reverify with my smd dd1.

 

[Osric]

I'll post the screenshots later, but the observed behaviour on my amps is:

- when switching from stereo to 4ch, the gain is higher, and if tuned for stereo the signal is clipped
- when adding a splitter to feed both inputs, the gain behaves as though you switched to 4 channel
- tuning the gain again for 4 channel gives the same peak to peak voltage as in stereo mode

So at least for volume purposes, there's no benefit to the splitter if you are going to tune to avoid clipping.

However, since I had the splitters anyway, I put both amps into 4 channel mode and tuned all 4 levels. I've shorted the rear cabin speakers so that the sound bar is louder, and those speakers make no noise. Using the splitters, I routed all the rear channels to the soundbar and tower speakers, and the front channels to the front speakers+swim deck speakers. So now, fading to rear puts more volume out of the tower, and fading to front puts the volume in the bow and swim deck. I tuned it so that when centered there is no clipping, which means the fader can cause clipping when pushing more volume out of the tower.

This is I think the best I can get it for watersports until I build the adapter to wire up the speakers in parallel instead of series.

Osric

 

[Osric]

I should have done a better job recording what my screenshots were. In any event, the top one of these is after connecting the splitter so that both inputs were wired up to an input signal. The gain immediately jumped and the clipping is clearly visible at the top and bottom of the output signal in cyan (input signal in yellow). I couldn't help but notice that the head unit outputs as much or more voltage than the amp, but knowing nothing about stereos I assume it's not capable of delivering enough power to the speakers even if the voltage looks the same.

The second image is after switching to 4 channel mode, but before tuning is done. After tuning up the signal, you wind up with intput/output like this:



And this looks and sounds pretty good. I am now into a pattern of tuning against a series of -3db videos from youtube, and then playing "my name is jonas" and watching for clipping (it's among the highest record level/loudest tracks on one of our main playlists).

So I believe my current configuration is as good as the stereo can sound for a rider without adding an amp or rewiring the speakers; next step is rewiring the speakers. A recap of what's working so far is:

1- short the rear cabin speakers to give full power to the sound bar
2- tune all the gains to avoid clipping at 100% volume, center fader; turn on the HPF and set the dial as low as it goes (which is different on the two different amps; in both cases choosing the bottom)
3- added splitters to route signal such that "rear" to the head unit is the soundbar+tower speakers, and front is swim deck+bow speakers

This is easily audible from the tube or wakeboard, a little tinny perhaps, but audible.

 

[Osric]

OK so I finally received the connector I was ordering from Amazon to change the wiring on the boat. Here it is on the seat of my boat, and partly connected just to be sure it fits, and it does of course.



The female end goes to the amps (we labelled it "boat") and the male end goes to the tower. The wiring matches up like this on the boat side:

green boat wire labeled LRS+ --> brown boat side wire
green black boat wire labeled LRS series --> orange
red - RRS+ --> pink
red black - RRS Series --> white
blank --> grey
blank --> purple

red - solar panel + --> yellow
black - solar panel - --> black
green - left tower + --> white
green black - left tower - --> green
blue - right tower + --> blue
blue black - right tower - --> red

So on the boat side, shorting brown+orange in the connector and pink+white will isolate the cabin speakers from the sound bar that they are normally in series with. On the tower side, the brown wire connects to the white wire that leads back to left tower +; and the orange wire connects to the green wire that leads to left tower -, putting the left tower speaker in parallel with the left tower sound bar. Similarly, the pink wire goes to the blue wire, and the white wire goes to the red wire, where the blue and red wires lead to right tower + and white tower - respectively. Here are some photos of putting that together:



Finally inserting the adapter into the boat, victory! The sound bar and tower speakers get full power, as do the cabin speakers.

It was almost midnight by the time we installed it in the boat so we couldn't do a sound system test at any high volume, but tomorrow we'll take it out wakeboarding and surfing and see if we can hear the difference.

 

[Rod5]

Wow that’s awesome! Thanks for putting in the link to the exact plug too!!

 

[Osric]

I got a chance to take this out tubing this morning and OMG THE SOUND BAR IS LOUD. Fade to rear powers the tower speakers, sound bar, and swim deck; and fade to front powers the cabin speakers and the bow speakers. So this is just how I wanted it; people who don't want to be blown away by the music can sit in the bow, and the sound is super loud in the back and for the riders. In fact several times when I was driving I turned it down from max because it was too loud, even for me.

Pretty happy with that!

Also, for those who are frustrated with Yamaha's volume control, set it to 100% and use the bluetooth volume to get finer grained control of the high end volume. If you're playing music quietly this isn't great because you can hear the buzz of the noise in the system, but at speed it works well. When stopped, 80% or so is probably more than loud enough.

This I believe is probably the optimal setup for the stock speakers on the 242X E-Series boats (mine is a 2017) with polk amps in the underseat compartment with the batteries and polk speakers + wetsounds sound bar. Building the connector is straightforward if you've done some soldering and removing it takes you back to the stock setup.

 

[Dave burke]

Very helpful @Osric. What kind of oscilloscope are you using?