Stereo tuning

[Cibolasam]

I have a 97 Sport. The stereo sounds good, but I think it could be better. It has an Alpine deck, a JL 300/4 pushing 4 Infinity Kappas 1 set up in front componet using 2 channels of the amp, the other 2 channels are pushing 2, 5 1/4 T series fusion speakers. I have a JL 500/1 pushing a 10W6 in a box I believe is too small. Any ideas on how to make this system sound better? Maybe a preamp? Also does any have pictures of a sub setup for this boat. Any help would be greatly appreciated.

[Mikeski]

RE: Stereo tuning

Here is a post I made on another site:

I would guess that you have some installation issues. Your speakers are pretty good, your amps could be stronger but they should do OK. A very significant aspect to any installation is the final tuning. A well tuned system using low end gear can often sound better than a poorly tuned system using high end gear.

Starting with the tower. This should be the most influential component in your system. Get those 6100's in check and they should just about drown out the boat. You should not get any feedback unless you are talking into the mic when you are in front of the speakers. This happens with all PA systems. If your tower amplifier has a crossover set it in high-pass mode at 150hz. This will allow the tower speakers to get the most out of the power not wasting power on lower frequencies that they cannot produce. The lower frequencies don't make it to the rider anyway.

Next work on the boat. Just like the tower, set the amplifier for the boat speakers in high-pass mode but lower the XO point to 100hz. The more speakers you introduce into the mix the more complex speaker phasing becomes possibly causing sound cancellation. Run the towers and one set of boat speakers, reverse the +/- wires on the boat speakers and see if they get louder or if they get quieter. You should leave them wherever they are loudest. Disconnect those then try it with the next pair of boat speakers. Hopefully you will find that all of the boat speakers can be wired the same way.

Now for the sub, your sub amp's crossover should be set at 150hz in low pass mode. Because it is crossed at the same frequency as the tower you should not have any issues with phasing with the tower. But because you will have an overlap with the boat you will need to make sure your sub is in phase with your boat speakers. Test the boat and sub then reverse the wires on the sub to see if the bass becomes stronger or weaker. Leave it where it is strongest.

It appears that you have three amplifiers, but have disconnected the Infinity amp? If your wiring is done correctly it should sound better using the Infinity amp. You may want to try to get that amp back into the mix.

One final note. It is very important to use large gauge power wire in boats for both the (+) and (-) wires to the amps as well as using high quality RCA cables.

Good Luck

[zax185]

Mikeski, good post. I was going to ask if there were phase [problems in boats like there are in cars and now I know. Almost every car I had in the past needed the front kick panel’s phase revered to increase the mid bass as well as sealing the doors.

[jbno1qb]

I second the compliment to Mikeski, but 150 Hz is too high of a crossover point for the sub. Bass frequencies that high are too easily identifiable, making the sub easy to "place" or "identify." I don't see a reasonable application that would require him to have the crossover any higher than 120 Hz, and I would much prefer something around 90 Hz. If you set the 300/4 at a 12db rolloff you should be just fine with no audible valley in frequency response.

Make sure you have the infrasonic filter on on your 500/1. Set it at about 30 Hz and move up.

What would really be helpful is if you would describe what you want to sound better. What aspects of the stereo are not to your liking?

[Cibolasam]

I would like the bass to sound cleaner. It seems to have too much mid bass. I would like to add another sub, but space is a problem. Also forgot to mention the deck has x/overs in it also, do I just set those to flat and use the amps for all that stuff? What got me thinking about all this was reading about speaker phasing problems, thats what I'm wondering if I have a problem with. Thanks for all your imput. Sam

[Mikeski]

Just looked at my settings last weekend, looks like I thought 150hz on the sub was too high too. Noticed that it was down around 100hz.

I also recently installed a ported sub in my truck. The ported sub makes way more mid-bass than the sealed sub in my car. The car is running at 150hz, the truck is running at 100hz, the boat has both a ported and sealed sub...

I think I will rebuild the seat sub with two 10's it's just a matter of time before I smoke the little 6.5's. gotta stop hanging around Grant...

[zax185]

new Alpine PDX amps vs JL Audio marine amps. Do you think the non marine amp will last? What I was going to do is take a pair of 12W3 I have and make a part MDF part Fiberglass sealed box to go on the left side of the cooler. I was going to uses the PDX 600.1 to run the pair or go with one 13W3V3. This speaker is less than twenty pounds and requires less space then the 13W6V2 or the 13W7. I am not looking to get 155db just a nice clean tight speaker. I listen to heavy music so I run my crossover down in the 50’s to only pick up the kick drum and not the bass guitar. Thanks

[WakeSlayer]

I have an Alpine PDX in mine, it is awesome. Not too worried about it being non marine, it is in a safe dry place.....

[phantom268]

I would certainly lower the sub crossover setting to 80-100hz...150hz will probably make it sound way too boomy and have too much midbass. That should clean up the sub sound quite a bit. I would think a 10W6 would be plenty of sub for you, don't know if adding another will be that beneficial. That's one of the best subs you can get IMO.

Do you know the airspace in the box you're using? And is it sealed or ported? That could definitely have an impact on your sound if its not in an appropriate box.

Also how are your gains set on your amps? What does the volume go up to on your head unit? My last Alpine went up to 35. When does it start getting loud enough for you? If its getting loud at like volume 10, your gains are set too high and it will hurt your sound quality. You want to tweak them out and balance the sound to where you turn the volume up to at about 75% of max volume. Trust me...it made a night & day difference on all my systems I couldn't believe how much my sound improved and how much more dynamic range there was. no point in going from barely audible to blasting with just a minor volume adjustment. So if your Alpine goes up to 35, I'd recommend tweaking it so the volume is appropriate at about 25-30 on the head unit.

Finally the dealer I use typically can setup something like a preamp with multiple volume controls that lets you adjust the volume of cabin speakers, tower speakers, and sub independently so when riding you can pump the tower speakers but turn the cabin speakers down so its not blasting you outta the boat haha. Something to consider anyway.

[Cibolasam]

Thanks

I took your advice on the gains. Stereo never sounded so good. Also just did th 100 amp alt upgrade. All is well. Sam

[phantom268]

RE: Thanks

Good to hear glad that worked out for you!