Suggestions??

[Ultra21]

I'm getting ready to take the dive and had some questions about components and hookups. I was looking at the Kenwood mono Excelon X812D amp to push a set of Infinity 1250W subs. The amp puts out 533 watts rms at 4 Ohms and 919 W at 2 Ohms. My question is, if I'm using a single 300 W, 12" sub at 4 Ohms, can I later add another 300 W sub connected in parallel. My thinking is that the amp will have 533 watts for a single 4 Ohm sub and 919 W for a set of 300 watt subs at 2 Ohms. Will the amp operate OK like this or is 2 Ohms continuouse too much for it? What I like about the Kenwood is it's a class D and has a 2 speed cooling fan.
Second question; I'm looking at the Infinity 7541a, 4 channel amp for some Polk DB650's. I couldn't find what resistance the 6.5" speakers operate at. Since the amps advertise operation at 2 and 4 Ohms, are the speakers 4 Ohms. I seem to recall speakers at 8 Ohms. I was hoping I could connect 8 speakers by connecting 2 in parallel to each channel. Would this drive each channel into 2 Ohms? and at 2 Ohms the amp puts out 139 Watts rms, will this drive the 60 watt DB650's OK? or will I have to add another 4 channel amp?
Thanks!!

[Kim Hanson]

I'm getting ready to take the dive and had some questions about components and hookups. I was looking at the Kenwood mono Excelon X812D amp to push a set of Infinity 1250W subs. The amp puts out 533 watts rms at 4 Ohms and 919 W at 2 Ohms. My question is, if I'm using a single 300 W, 12" sub at 4 Ohms, can I later add another 300 W sub connected in parallel. My thinking is that the amp will have 533 watts for a single 4 Ohm sub and 919 W for a set of 300 watt subs at 2 Ohms. Will the amp operate OK like this or is 2 Ohms continuouse too much for it? What I like about the Kenwood is it's a class D and has a 2 speed cooling fan.
Second question; I'm looking at the Infinity 7541a, 4 channel amp for some Polk DB650's. I couldn't find what resistance the 6.5" speakers operate at. Since the amps advertise operation at 2 and 4 Ohms, are the speakers 4 Ohms. I seem to recall speakers at 8 Ohms. I was hoping I could connect 8 speakers by connecting 2 in parallel to each channel. Would this drive each channel into 2 Ohms? and at 2 Ohms the amp puts out 139 Watts rms, will this drive the 60 watt DB650's OK? or will I have to add another 4 channel amp?
Thanks!!
Just get 1 big amp to power everything...........( . )( . )..........:idea:

[Dub C]

I'm getting ready to take the dive and had some questions about components and hookups. I was looking at the Kenwood mono Excelon X812D amp to push a set of Infinity 1250W subs. The amp puts out 533 watts rms at 4 Ohms and 919 W at 2 Ohms. My question is, if I'm using a single 300 W, 12" sub at 4 Ohms, can I later add another 300 W sub connected in parallel. My thinking is that the amp will have 533 watts for a single 4 Ohm sub and 919 W for a set of 300 watt subs at 2 Ohms. Will the amp operate OK like this or is 2 Ohms continuouse too much for it? What I like about the Kenwood is it's a class D and has a 2 speed cooling fan.
Second question; I'm looking at the Infinity 7541a, 4 channel amp for some Polk DB650's. I couldn't find what resistance the 6.5" speakers operate at. Since the amps advertise operation at 2 and 4 Ohms, are the speakers 4 Ohms. I seem to recall speakers at 8 Ohms. I was hoping I could connect 8 speakers by connecting 2 in parallel to each channel. Would this drive each channel into 2 Ohms? and at 2 Ohms the amp puts out 139 Watts rms, will this drive the 60 watt DB650's OK? or will I have to add another 4 channel amp?
Thanks!!
for continuous use, run them a little on the high side, if it's rated to operate down to 2 ohms, this is assuming ideal voltage (14.4) and not being played a a very loud volume, you have to figure in a car you would maybe listen to music loud for what, a half hour maybe? Home amps tend to be more robust for this and having 110 volts to start from isn't bad either. what causes heat/damage in amps is current, the lower the voltage the more current is needed to produce power, lowering resistance causes current to increase, a combination of these can make an amp really stress. a simple formula is voltage = ampsXresistance so a 4ohm light bulb connected to 12volts= 3amps of current (4x3=12) if you connect the bulb to 14v, 4x3.5amps= 1/2 amp more current but the forumla for power, at least the simplest is volts X amps = watts so at 12volts-- 3A X 12v= 36watts but 14v-- 3.5A X 14v=49watts. In a nutshell by adding 2 volts with the same resistance (components like amps and speakers) we have 36w vs. 49w with the same equipment! run them at 2 amps if you are not going to play the system for very long periods of time and/or have plenty of battery power.

[Concept1]

Just my .02 I have JL audio in my new boat and its awesome. I have two JL 13w1, and 8 6 1/2 components and I run it off a JL 500/5, it ROCKS. JL is boat friendly because it doesnt draw alot of current. Those big power handling subs are usually heavier as well. Check into JL stuff. I have another brand new 500/5 for pretty cheap that will run your whole system as well if you want to get it.

[WET HULL]

Dub C is right on the money. I would run two amplifiers for the speakers, and one for the subs. With two amps you can turn your gain down to 3/4 and keep the speakers at 4ohm. Plus if you blow a speaker you can kill just that one rather then the whole side of your boat. You will still end up using about the same amount of power off the batteries, but you will be running cooler and the amps wont be working so hard. Boats are a whole different world compared to cars, and the 115 degree weather does not help either. As far as the JL Audio goes, thats all I run. The amps however are very power hungry. You might want to check out the Alpine PDX series, they are very conservative when it comes to power use. If power is not a issue, go big or go home.:D Put external fans running across the amps. The Kenwood gets the heat out but you still need to move it away from the amps. I use bilge blower fans. Good luck. If you need pricing on stuff let me know.

[Concept1]

Dub C is right on the money. I would run two amplifiers for the speakers, and one for the subs. With two amps you can turn your gain down to 3/4 and keep the speakers at 4ohm. Plus if you blow a speaker you can kill just that one rather then the whole side of your boat. You will still end up using about the same amount of power off the batteries, but you will be running cooler and the amps wont be working so hard. Boats are a whole different world compared to cars, and the 115 degree weather does not help either. As far as the JL Audio goes, thats all I run. The amps however are very power hungry. You might want to check out the Alpine PDX series, they are very conservative when it comes to power use. If power is not a issue, go big or go home.:D Put external fans running across the amps. The Kenwood gets the heat out but you still need to move it away from the amps. I use bilge blower fans. Good luck. If you need pricing on stuff let me know.
Wet Hull, do you think that JL really is power hungry? I havent used the Alpine amps but i know ive used alot of other ones and the JL always runs the best. I guess im comparing to Fosgate amps, I took those out of my old truck when the JL ones came out and hte lights never even dimmed at full volume. The fosgate ones looked like they would almost shut the truck off.

[thmper321]

The trick with amps in boats is regulated power supplies. JL and the Alpine PDX amps are regulated. Rockford amps are not regulated thus the lack of efficiency. Rockford amps are probably the worst of all the popular amps in regards to efficiency. JL and Alpine seem to be the most popular in boat systems.

[WET HULL]

Whats up Concept One. Your boat is sick. To answer your question the JL amps are very power hungry. They are a little less then the Rockford though. The JL are some of the best in my opinion, and I will not use anything else. I currently have 5 of the JL slash series amps in my boat, but I am also using the generator set up. They will drain your batteries a whole lot faster then the new Alpine PDX series, but its all relevant to how you play the stereo. Do you park on the beach all day and crank it as loud as possible or just for an hour at a time and then cruise around? You have the room to add more batteries if needed or go the generator route so don't stress. Plus you only have the one amp. For the smaller boats with little room to add more batteries it might be better to go the Alpine route if you plan to crank it at high volumes for a long period of time.

[Concept1]

Whats up Concept One. Your boat is sick. To answer your question the JL amps are very power hungry. They are a little less then the Rockford though. The JL are some of the best in my opinion, and I will not use anything else. I currently have 5 of the JL slash series amps in my boat, but I am also using the generator set up. They will drain your batteries a whole lot faster then the new Alpine PDX series, but its all relevant to how you play the stereo. Do you park on the beach all day and crank it as loud as possible or just for an hour at a time and then cruise around? You have the room to add more batteries if needed or go the generator route so don't stress. Plus you only have the one amp. For the smaller boats with little room to add more batteries it might be better to go the Alpine route if you plan to crank it at high volumes for a long period of time.
Thanks for the compliment man! O.K. that makes sense, I knew the Fosgate drew alot but since my lights didnt blink at all with the JL ones I just figured they were alot more efficient! We just got the stereo done a week ago and New Years Day was the first time out so I dont know about the duration of playing just trial and error I guess is the best way, as long as Ionly have 1 battery on at a time! :-) Well at least now I can be more consious about what i say, I hope I wasnt giving out too much bad advice!

[Dub C]

another thing to keep in mind in terms of efficiency is a huge amp playing speakers lets say 50 watts and 80 decibals, is much more efficient than a smaller amp doing the same amount of work, once an amp is pushed hard the current draw goes way up, think 8cylinder car driving at freeway speed at low RPM's vs. a 4 cylinder working hard to go 75mph.

[WET HULL]

No worries, at least you get involved in the converstion, and are learning new things which will help you in the future. A boat stereo is never right the first time. I have added more and more to mine because of trial and error. Make sure you have some fans going across the amps, you will need them in the summer. Push it to its limit and see how it does while its still under warranty.:devil: Good luck.

[Concept1]

Yep well thats why im here! To learn all I can and meet some cool people snad thats exactly whats been happening. Your boat is sick as well, I love the speaker pod ideas, I saw them a while ago and since like 50 people commented on how vad ass they were I figured it was getting repetitive but oh well, BAD ASS anyway! When you get all set up with your store do you plan on setting up with JL ?

[WET HULL]

I already am set up with them. Thanks for the compliments, they were fun to make and I have new ones under the engine hatch holding four of the JL XR-650 component speakers. If you need anything let me know. I will post pics soon. I might start offering them to people in the near future.

[Concept1]

I already am set up with them. Thanks for the compliments, they were fun to make and I have new ones under the engine hatch holding four of the JL XR-650 component speakers. If you need anything let me know. I will post pics soon. I might start offering them to people in the near future.
Sweet im in for a set. I have ARC audio speakers in the boat right now because it came with them, we just added 4 more 6 1/2's so there is 8 now. But who cares Ill do more for some of those pods, maybe a TV too???

[WET HULL]

I will get you some pics once I am around the boat again. You would need another 4 channel amp for these. They are very loud and crystal clear when powered correctly. They give you four mid base and for tweeters in the pods.

[Concept1]

I will get you some pics once I am around the boat again. You would need another 4 channel amp for these. They are very loud and crystal clear when powered correctly. They give you four mid base and for tweeters in the pods.
Only for the JL speakers? I have an extra 300/4 laying around...

[WET HULL]

I can build in any speakers that you want. I would want the speakers first that way I have all the designs correct. I can design you your own pod that will be an Amped Up original. Any special angles you would want and paint scheme, the sky is your limit. Damn I sound like a salesman.

[Concept1]

I can build in any speakers that you want. I would want the speakers first that way I have all the designs correct. I can design you your own pod that will be an Amped Up original. Any special angles you would want and paint scheme, the sky is your limit. Damn I sound like a salesman.
Sounds good thats the new business so you have to be. Try this go to www.nextcustomboats.com and click on the boat links, mine should be in the power boat photo shoot section. You might be able to see the interior better in those shots to get some ideas about angles and paint. Long as it matches the colors and looks good you will be turned loose!

[rivercrazy]

Regulated amplifer designs drain batteries faster than non-regulated designs, especially once the battery falls below 12V.