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View Full Version : The NOT ANOTHER AMPLIFIER THREAD, thread


Ric
04-28-2006, 07:01 PM
I believe I've made a slight error in judgement....

many of you may know my 190 had LTS ballast
I had 3 amps in that boat (1 atop the LTS tank, one mounted to the under side of the deck foreward of the drivers pod and one on the drivers side front of the divider wall in the bow storage in front. )
You could not see any of them. It was nice.

NOW
I installed all three in the 197 all in the obs side storage
(1 on back of the bow seat wall, 2 on the wall adjacent to the walkthru)

I don't get loud often but we were hanging out at the lake easter weekend and I cranked some buffet for awhile (5 or 6 songs)
allofasudden, the radio cut out and I jumped in the boat and shut off the key... thinking I'd killed the battery
I opened the obs seat to see how hot the amps were (dont ask me why......)
and the sony and one of the alpines were so damn hot, they burned my hand!!! :eek:
had we any plastic bags, life jackets etc in there, they may have either melted or caught fire :eek:

Deisel and others, have I reached a point were I need to break down and get one amp to drive 2 fronts, 2 rears and one JL 10" seperately (5 channel?) and mount it in a more obscure location??

east tx skier
04-28-2006, 07:06 PM
Wow, that's scary. My stereo is too Mickey Mouse to burn anything. Just a tuner and four 13 year old speakers. The tuner has a wireless remote and plays mp3s. That's not enough to cause a fire though.

tex
04-28-2006, 07:35 PM
I just have 2 turntables and a microphone...

RackAtak
04-28-2006, 07:37 PM
...Deisel and others, have I reached a point were I need to break down and get one amp to drive 2 fronts, 2 rears and one JL 10" seperately (5 channel?) and mount it in a more obscure location??
I have a 4 channel amp that is 2 ohm stable. If your amp is 2 ohm stable you can run 4 speakers and a sub off of a 4 channel amp.

I ran my 2 fronts wired in parallel for 2ohms and 2 rears also wired in parallel for 2 ohms off of the right and left front channel of the amp. I ran my dual voice coil sub off of the rear channels. If I had a single voice coil sub I would have bridged the rear channel of the amp.

RackAtak
04-28-2006, 07:43 PM
Here are a couple good wiring examples

http://colomar.com/Shavano/spkr_wiring.html

http://www.bcae1.com/spkrmlti.htm

east tx skier
04-28-2006, 08:05 PM
I just have 2 turntables and a microphone...

... That was a good thread jack ...

/what about ...ac/dc?

JimN
04-28-2006, 08:06 PM
One thing to know about wiring a whole bunch of speakers to one amp channel- as the # of speakers increases, so does the inductance and some amps don't deal with that very well at all. Not all amps will handle 2 ohms well. Don't wire them this way unless they specifically state that they will. In theory, power increases with a decrease in impedance but in practice, it just doesn't work well unless the amp is designed to be wired that way. Any time an amp is wired to a lower impedance load, it will draw more current and needs heavier power wire.

Ric- You need to make sure the amps aren't mounted flat to any kind of panel or upside-down. They can't throw off enough heat that way and heat is the killer of all things electronic and mechanical. Also, if the wire gauge to the amps is too small, the amps will overheat and puke. This is an absolute. Small wire can't conduct enough current to drive the amps and when the battery voltage drops, in order to put out the power you are trying to, they will draw more current. Period. Also, any conductor that gets hot will resist current flow more than at a lower temperature.

If you want to hide the amps (and who doesn't), add a fan to cool them, making sure the air can flow to and from them, freely. Parts Express sells long squirrel cage fans for this and you can get thermal switches to turn them on/off when the temperature dictates.

Look at the power terminals on the amps- if they're melted, you should be able to replace just the terminals but check the amps to see if they still work first.

JimN
04-28-2006, 08:09 PM
RackAtak- "If your amp is 2 ohm stable you can run 4 speakers and an amp off of a 4 channel amp." Huh? You mean use the speaker output to feed signal to another amp? Why would you do this when you could just use a Y cable?

Footin
04-28-2006, 08:16 PM
How about a four channel Sparkomatic.

RackAtak
04-28-2006, 08:17 PM
RackAtak- "If your amp is 2 ohm stable you can run 4 speakers and an amp off of a 4 channel amp." Huh? You mean use the speaker output to feed signal to another amp? Why would you do this when you could just use a Y cable?
You were supposed to understand that I meant 4 speakers and a "SUB" :D

I edited my post. :o

JimN
04-28-2006, 08:22 PM
Amp, sub. Three letters, same alphabet, hard to know the code. The an threw me off since an sub ain't proper grammar, ain'a?

Or, it could be wired in "tri-mode", where you bridge the amp, wire the smaller speakers in parallel with a cap for high pass and a woofer with a coil for low-pass on each channel. You get LOTS of sound that way.

Footin- I was thinking more like a Tancredi EQ/booster. Or Kraco. Morry Kraines would be happy to know that his company is still being discussed.

Footin
04-28-2006, 08:26 PM
Just remembering my car stereo in high school, Sparkomatic and Jensen.

Dam did I think I was cool.

JimN
04-28-2006, 08:27 PM
6x9 coax or tri-ax?

Footin
04-28-2006, 08:30 PM
Triaxle of course!

I can still hear Autograph, "Turn up the radio" or anything from the Firm jammin away.

mitch
04-28-2006, 09:39 PM
Jim is right, a fan would help a lot. If you're cranking for a while esp hanging outside the boat, prop open the obs seat. An unopened beer will hold it open nicely.

Ric
04-29-2006, 08:44 AM
One thing to know about wiring a whole bunch of speakers to one amp channel- as the # of speakers increases, so does the inductance and some amps don't deal with that very well at all. Not all amps will handle 2 ohms well. Don't wire them this way unless they specifically state that they will. In theory, power increases with a decrease in impedance but in practice, it just doesn't work well unless the amp is designed to be wired that way. Any time an amp is wired to a lower impedance load, it will draw more current and needs heavier power wire.

Ric- You need to make sure the amps aren't mounted flat to any kind of panel or upside-down. They can't throw off enough heat that way and heat is the killer of all things electronic and mechanical. Also, if the wire gauge to the amps is too small, the amps will overheat and puke. This is an absolute. Small wire can't conduct enough current to drive the amps and when the battery voltage drops, in order to put out the power you are trying to, they will draw more current. Period. Also, any conductor that gets hot will resist current flow more than at a lower temperature.

If you want to hide the amps (and who doesn't), add a fan to cool them, making sure the air can flow to and from them, freely. Parts Express sells long squirrel cage fans for this and you can get thermal switches to turn them on/off when the temperature dictates.

Look at the power terminals on the amps- if they're melted, you should be able to replace just the terminals but check the amps to see if they still work first.
cool
so I have 10gage power and ground to each amp seperately from fused terminals at the battery.

The system plays fine now so I'm not sure if the cutoff that day was heat or a dead battery or a combination of the two. I let it sit about 20minutes and then fired up the motor. the starter seemed to labor so I am guessing we nearly drained the battery...

they are all three mounted flat against the carpeted inner walls of the storage so maybe I should space them away from the carpet a bit and maybe get me a fan like that..

If there were an amp out there that would run all 5 of those speakers properly, I am guessing it would be huge.

Where in a 197, is there room to cleanly install a big amp to run all 5 speakers properly where it won't get wet and preferably won't be seen? hmmmmmmmmm

JimN
04-29-2006, 10:13 AM
What is the total of the fuses for each amp? 10 ga is good for about 30A at 15', less when the battery voltage drops. Another thing that is usually not great is just crimping terminals onto the ends and calling it good. Properly crimped and properly soldered is best. There is a difference.

There are amps out there that will run all 5 speakers. They aren't cheap and you already have enough channels of amplification. I would use spacers, increase the wire gauge and make sure the amps get enough air flowing past the heat sinks. I would also make sure the input sensitivity is set correctly. Too sensitive and you get major distortion, blown tweeters (sometimes woofers) and the amp will generally shut down intermittently from DC at the output.

Ric
04-29-2006, 10:24 AM
Thanks Jim, my connections are crimped on and I'm sure solder would be better
I will have to look at the fuses there is about 5-6ft runs of 10ga right now
maybe I will get a big cable set and run it to a distribution block near the amps
I don't want to have to worry each time we take the kids out to the public lake that there might be some gear laying against an amp that could cause issue... I will be re-thinking the entire setup.

JimN
04-29-2006, 10:35 AM
Why not put a cover over the amps in the storage area, with a 2" space over it and a fan (the long squirrel cage I mentioned before)? That way, you get the storage, cooling and protection.

Ric
04-29-2006, 11:19 AM
Why not put a cover over the amps in the storage area, with a 2" space over it and a fan (the long squirrel cage I mentioned before)? That way, you get the storage, cooling and protection.
I like that idea!

BrianS
05-01-2006, 08:15 AM
I think you are thinking about this the wrong way. If you go to only 1 amp to run your whole system, it is going to be loaded down more which equals more heat. When you start bridging channels together and reducing loads to 2 ohms that causes more heat.

You could use a JL e6450M which is a 6-channel amp to run the 4 mids and bridge 2 channels for the sub. That would leave the load on each channel at 4 ohms which shouldn't be too bad.

No matter what you do, when you crank the tunes your amps are going to get hot. The best bet is going to be using spacers to allow air to get all around the amp, and adding fans to keep air moving across them.