subwoofer does not sound good

[jt1989]

Hello again,
I recently installed a mtx thunder tm1004 10" subwoofer in my boat. I bridged my amplifier so the sub is receiving 160w at 4 ohms. The sub sounds ok at low volume, with the bass boost turned up about 2/3 of the way...at higher volume it begins to sound really cheap...is it just that it is a cheap sub? is there a certain way to set up the amp to clear it up? also the speaker wire to the sub is pretty long, could that make a differece? Any advice helps. I tried messing with the amp some today, but ran out of time...
Thanks

 

[Ryanlewis2010]

Re: subwoofer does not sound good

sorry to be a downer but when it comes to Audio any 60 dollar amp is gonna stink at high volume then you add a marine in fornt of that it becomes even worse lol good car sub=150 kicker audio good marine sub = 230 ______ audio.

just my .02 but i will say jl audio has some good low end price ones that should work fine with the water as long as your electrical is all sealed

 

[jt1989]

Re: subwoofer does not sound good

I got the amp for free, which is a total mobile audio, a throwoff of jl or whatever you wanna call it. Its a t320.4 model. I spent about a month's salary on the rest of the sound system, and just figured if I could get a little bass in there that would be fine. Ill upgrade later as I have put more money into this sound system than I probably should have. So maybe for now just turn down the input sensitivity on the bridged channel until it takes away the distortion? Is that the best route to go?

 

[Ciera2450]

Re: subwoofer does not sound good

I'd try adjusting things to minimize the distortion at higher volumes. First, turn the bass boost down on the amp and try tweaking the gain a bit to get the right sound at the volume you want. MTX makes decent(ish) speakers but if the amp pushing it isn't up to snuff it will sound bad. What is the THD rating for the amp?

 

[Ciera2450]

Re: subwoofer does not sound good

Also, is the subwoofer in the proper size enclosure? This can make a huge difference in the sound.

 

[riptorn]

Re: subwoofer does not sound good

Do have a picture or an identification were you put the sub setup? A subwoofer is pretty basic. Did you bench test the system?
The longer of the wire the lower gauge you go. How long? 40ft?

 

[H20Rat]

Re: subwoofer does not sound good

how big is your power and ground wires going to the amp? What size fuse on the amp? I just got done building a fairly massive stereo system in a friends boat, 3000 watts going to the subs, 4 kicker subs mounted in isobaric pairs. The thing is painfully loud!

 

[jt1989]

Re: subwoofer does not sound good

The power and ground wire are both 8 guage wire...is that too small? I believe its a 60 amp fuse but im not for sure. I'll have to get back to ya on that. The speaker wire is about 20 ft....what guage wire speaker wire would be ideal for that length? The enclosure I used was designed for a 2012 f150, but I decided to ditch the money on installing a sub in my truck for a set of kicker ktm6's for the tower So I used that 10 inch box. Seems like it might be a little small, could be the problem. I am away from the boat but I can get a picture tomorrow if that will help. The ktm6's installed on channel 1 & 2 on the amp sound AWESOME at high volume. But im a newbie at this amplifier setup thing.
Thanks for the help

 

[Mischief Managed]

Re: subwoofer does not sound good

160 watts is not a whole lot of power to work with. You are probably just over-driving the amp and making it clip. Clipping occurs when the output waveform attempts to exceed the bias voltage on the output transistors, it turns a smoothly rounded wave peak into a flat wave peak and that sounds awful when you feed it into a speaker. You can lower the input level to the amp or reduce the gain of the amp to stop the clipping.

Bigger speaker wires won't make any difference. You can run 160 watts into a 4 ohms load through very small wire. There's less than 7 amps of current and low frequency signals are not at all challenging to transport 20 feet. 8 Gauge power and ground wires are more than adequate.

That mtx thunder tm1004 has only 86.4 dB of advertised sensitivity. If you replaced it with a speaker that has 92.4 dB of sensitivity, it would have the same effect on the sound as having a 640 watt amplifier and might solve your problem. This one is rated for 93 dB: http://www.hookedontronics.com/sales/D628399f7d1728_P117_Dti_DW100MR.htm I have no idea if that's accurate though, I doubt marine subwoofer specs are strictly governed...

 

[mark1905]

Re: subwoofer does not sound good

You have two issues here:

First, you need a much more powerful amp to drive a subwoofer.. something that's pushing at least a few hundred watts RMS. Amps are dirt cheap these days and for less than $100 you could get something that would work.. and for $150-$200 you could get something that would melt your ear drums. My HiFonics 1700w class D amp was $200 and I'm driving 2 x 3500w Pioneer competition subs with it @ 1ohm.. and my teeth rattle together if I turn it up. Literally. It's way, way more than I need.

It looks like you have this amp here: http://www.onlinecarstereo.com/CarAudio/p_18634_Total_Mobile_Audio_T3204.aspx - which is only rated for 60w x 4.. AND this is an off brand.. meaning.. I bet you're putting out like 30w per channel.. you're not driving a sub with that.

Second and actually foremost.. when you're trying to add bass on a boat, it becomes extremely difficult due to the acoustics in open air. Bass frequencies are literally very long waves of sound and they like to resonate in things. When you have subwoofers in the back of your car, the bass waves are bouncing all over the inside of your vehicle and actually amplifying the sound. When you put that same speaker in the open air (ie - on a boat), the waves have nothing to bounce off of and literally just get sucked up into the open air leaving you with no volume. Meaning.. you're going to have to either drive the hell out your subs with a monster amp, or build/place the subs correctly in order to amplify.. (or in my case.. both )

For a boat, I would highly recommend looking at a Bazooka enclosure for many reasons. They're a weatherproof enclosure that's tuned right to maximize sound through porting and you can mount them anywhere while "corner loading" the sound. In a runabout, they fit nicely up under the dash. Check these pictures out:



Here you can see the 12" enclosures fitting perfectly under either dash of my 18' bow rider. They fire directly into the corners of the boat and amplify like CRAZY.



Here is a closeup of how they fire. This isn't a case of your speaker or power wire or subwoofer sensitivity levels, this is just simple audio system building in a boat.

For off-brand amps, people really seem to have good luck with SSL products: http://www.amazon.com/Sound-Storm-L...79C6/ref=sr_1_4?ie=UTF8&qid=1335536557&sr=8-4

If you want quality + marine durability, go MB Quart. Best bang for your buck by far for a marine amp. The listing is wrong, BTW.. it's a 240w amp.. not 180w. Not the biggest amp in the world, but your choices are very limited in marine when it comes to anything more than 60w per channel: http://www.amazon.com/MB-Quart-NAU4...1?s=electronics&ie=UTF8&qid=1335536678&sr=1-1

 

[NSBCraig]

Re: subwoofer does not sound good

Yeah your running way to little power for a sub

 

[jt1989]

Re: subwoofer does not sound good

So that MB quart 4 channel will be enough to drive 2 subs (bridged) for decent sound quality? Should I look at different subs as well? What would ya'll recommend?

 

[halfmoa]

Re: subwoofer does not sound good

is it just that it is a cheap sub?

I've had that same sub and yes, it's a entry level. Mine lasted maybe 6 months. Also I've found that LOWERING the bass on the head unit and cranking the amp output can be helpful in most applications. I'm surprised no one asked, but do you have this running off a crossover or is this sub getting full range? That'd make a lot of difference too. Being a new setup I'd play with all the settings before I wrote it off as junk entirely.

Keep in mind that a 10" sub running off a no name 160w amp isn't gonna rattle your teeth, just fill a void in the sound.

 

[mark1905]

Re: subwoofer does not sound good

So that MB quart 4 channel will be enough to drive 2 subs (bridged) for decent sound quality? Should I look at different subs as well? What would ya'll recommend?

It depends. If you can mount the amp in a place that isn't exposed to the elements, you want some strength behind that sub you don't mind the risk of moisture on a non-marine amp and you don't want to spend a ton of money.. then go for a non-marine amp like I posted. For under $70, you'll be driving the heck out of that subwoofer and may even blow it if you're not careful. If you want quality and long lasting but don't mind not having tons and tons of power on the sub, that MB Quart will do just fine. Bridge channels 1+2 and 3 + 4 together for each sub. But.. it's still not going to be anything more than just fill. If you want bump, you're going to need a higher powered non-marine amp.

For subs, those are also pretty cheap these days. You can get a good quality subwoofer from many different reputable brands for around $60-$80 that will do the job fine in your application. HiFonics Brutus series, Kicker Comp, Infinity, etc etc. Amazon has by far and wide the best prices and free 2 day shipping if you sign up for their free "Prime" trial membership. Just make sure to turn off auto-renewal so you don't get charged at the end of the month.

It really all comes down to how much money you want to spend. Stereo equipment is SO CHEAP compared to what it was 10-15 years ago, that now the difference between off brand, quality and power levels is literally like $100-$150 for each component.

Case in point: I paid $135 for my almost top of the line Pioneer 3500w competition subwoofers. I paid $200 for my HiFonics class D, 1 ohm stable beast of a 1700w amp. The difference in each of those between super high quality, POWERFUL equipment and off brand, lower power is about $70-$100 per component. Years ago.. it would have been about $700-$800.

Figure out your max budget for each piece of equipment, and choose accordingly by doing your research. I'm glad to help.