OK, I have the non-Bose audio system and I noticed that the 6x9 rear subs are 2 Ohm . Can someone who changed out there non-bose door speaker check the speaker to see if nissan also put 2 Ohm speakers in the door? I replaced my HU and am now worried that I may blow the internal amp due to the speakers being 2 Ohm instead of 4 Ohm.

 

I wanna say the door speakers are 2 ohms. I threw them out after I changed them with polks.

 

nissan likes to use 2 ohms speakers since it'll get the most power out of those pathetic stock amps. but for now, keep your volume down until someone can verify.

 

Bose uses 2ohm speakers.

 

i don't think the ohms wll blow anything.. is just another way to hook up the speaker to get more power out the amp with less use of current.. if anything the 4 ohm speakers are getting more or the same power and using less current.

i won't be worried about it you are fine. i did some reading on this before on the internet, look it up if you are still stumped..

 

Well, if it is two ohms that would explain why the stock speakers sound so much louder, but am concerned abount blowing the HU internal amp.

SmokeMaximus, didn't you replace the 6x9 subs too? I was wondering if you kept the oem amp or replaced it with an after market.

 

Unless your headunit is 2 ohm stable, you will definately blow it evenually if you hook up 2 ohm speakers to it. It prolly wont happen right away but while you are playing music on 2 ohm speakers with a 4 ohm stable headunit, the internal parts of the headunit will start to deteriorate and melt from the intense heat that the lower resistance generates and will blow eventually. I would suggest to replace all the speakers with new aftermarket 4 ohm ones and dont even risk it unless you have a great warranty. Also, I have the bose system and the subs in the back are 6 1/2s, not 6 x 9s. Im not sure if your car is different since it has nonbose but I would double check the size as well.

 

i don't think so,

the amp is what converts the ohms to 2 not the HU. the HU gives out 4 all the way to the amp and it becomes 2 from there. you have to read a ohm write up to belive me..

remember that 2 ohms is less than 4 in current... the HU is giving 4 and the spk is taking 2, whats going to blow?

also if you hook up a 4 ohm spk to it, it will also get 2ohm from the bose amp.. its better for the spk..

you are ok..

 

No I ended up bypassing the oem amp. I ran the wires from the 6x9's directly to the amp. It can mess up your amp to have 2 amps wired together like that.

 

Im sorry but I Do not agree with you. How could 2 ohms be less than 4 ohms in current?? Ohms is the unit of resistance. The more ohms(resistance) in a circuit, the LESS current will flow through it because of the extra resistance.

The headunit has a built in amp in it. Hooking up 2 ohm speakers to ANY amp that is only stable at 4 ohms will cause it to blow. Therefore, if he hooks up his 2ohm speakers directly to his headunit that has a built in amp which can only be stable at 4 ohms, it will eventually blow. The lower the ohms (resitance) the more current is allowed to flow through the circuit, the hotter parts get and the more problems it will cause if the parts cannot handle the current.

 

^^it's true


I would recommend changing all the speakers , I doubt that it would actually damage the H.U. but it's not good to overload it.

 

I beg to disagree with you. In the case of speakers the normal ohm reading is not a measure of resistance but a measure of IMPEDANCE. It has been too many years for me to pull up from the bottom of my mind the differece between resistance and impendance -- but there is a difference. The coil of wire in a speaker has both resistance and the ability to create a magnetic field. The two combined (if my memory is right) results in a measure of speaker impedance. The idea with connecting speakers to an amp is to have the amp impedance connection come close to properly banancing the speaker impedance (measured in ohms). The difference between 2 ohms impedance and 4 ohms impedance is not that great. An internet search of "speaker impedance" should prove that this is the case. So, based on my memory of this situation, I believe that Tek-Niq's analysis is correct. Answer: Don't waste your money on new speakers, the ones you have will work OK.

 

the ohm's of a speaker has a great effect on an amp. if you have an amp that say is only 4 ohm stable and you have speakers that are 2 ohm stable then you run the risk of overheating the amp. now if you were to hook the speakers up in series which would equal 4 ohms (2ohm+2ohm) then all would be fine. but if you run them by themselves at 2 ohms then the amp would overheat. this is not done instantly but over a period of time depending on the cooling efficency of the amp. all amps have a stability rating which tells you the lowest ohm that it can operate at and for how long. basically the resistance slows the current down in the circuit and allows the amp to cool itself and not flow electrons at a rapid rate. dont want to give science class here. but if you take and amp that is made for 4 ohms and run it at 2 it will overheat. if it has the circuitry to with stand that then it should either blow a fuse or kick out provided that it has a protection for the circuit. if not it will just burn out channels or the amp gets hot enough to burn up but what actually happens is the solder reaches temps to where it liquifies and runs across the breadboard and thats what causes the amps to go. hope this i can break it down further but electronics is my speciality.

 

Thank you very much, THIS is exactly what I am trying to say! I HAVE blown amps in my earlier days because I was hooking up speakers that created a 2 ohm load to amps that were only 4 ohm stable and THE AMPS BLEW EVERY TIME!!! There is a HUGE difference between 2 ohms and 4 ohms when it comes to speakers and amps! Everyone can say all they want, but no one will be able to convince me that 2 ohm speakers cannot blow an amp that is only 4 ohm stable!

 

I haven't torn mine apart, but I know they are eight speaker systems. Since there is no such thing as an eight channel HU, I'll take a stab that the woofers are wired in series with the rear door speakers and the front door speakers are wired in series with the tweeters, which would give a 4 ohm load for all four channels. It isn't a problem using 4 ohm speakers, they just have to be wired in parallel instead of series.

Putting 4 ohm speakers in place without changing the wiring won't hurt the amp, but since there is twice the resistance, there will be half the volume.

If you have any question about wiring in series vs. parallel, shoot me a message or I'm sure you could find something out on the internet somewhere.

Scott

 

I can honestly say i am at a complete loss for words... so I looked at the service manual it show the tweeter in front are wired in parallel to front door speakers and the rear door speakers are also wired in parallel to the woofers in the rear deck. This can't be good for after market HU...

 

they have to be hooked up in a weird way you prob haven't seen to achive the 2 ohm's. I say look it up on google and you will see all the different wire diagrams in a system..

 

Now here is something interesting. I had one shop tell me that the 6th gen uses 1/2ohm speakers. I haven't found any hard confirmation, but I did find this replacement setup for the Bose system in the Mazda Miata

".... The factory Bose® equipped cars utilize a specially designed amplifier which needs matching speakers. We manufacture a system to accommodate this need. The Bose® replacement system is designed to work seamlessly with the factory amplifier. The impedance of this woofer is ½ ohm, just like the factory speaker. ...." http://www.clearwateraudio.com/cwc8b.htm

 

maximum power transfer will occur when the output impedance of the amp matches the input impedance of the speaker. The 2 ohm speakers have only one half the impedance the amp is designed for, this is a very large mismatch. You will cause greater heat loss in the power transistors on the amp. Adding a 2 ohm resistor will protect the amp but you will never be able to transfer full power to the speakers.

 

I wouldn't even try that. Like I said above, if it is a 4 ohm system and you use a 2 ohm speaker a 40 watt amp just became an 80 watt amp. A resistor won't help that problem either, see the above stuff about impedence vs. resistance.

 

well here's my 2 cents...

if an amp is designed to run at 4 ohms per channel, you'll risk overheating and damaging the amp by using 2 ohm speakers. sure it'll work for awhile, but the extra stress will quickly shorten the life of the amp. if it's not stable for low impedance usage, then try to stay within the amp's stable parameters.

 

Nuts I guess the best and safest thing would be to eventually get new speakers. Not exactly what I wanted to do

 

you don't have to spend a fortune on aftermarket speakers to get decent sound. just go visit some shops and have a demo of each speaker and see which ones you like/fit your budget.

 

I do know at stores like Best Buy and Circuit City, they have a computer program in the car audio section that will tell you the proper speakers that can be installed on any make/year vehicle. I just tried their online web sites and you can also do a search for speakers that will fit your car based on Year/Make/Model.

 

EXACTLY ......

 

Just a follow up for those who maybe interested, the nonbose door speakers are 4ohm the rear deck are 2ohm.