2 ohms speakers

You are right. I got my wires crossed. (no pun intended). It's been a while. Ohms law is I = V/R. Combining ohms law with the equation for power P=VI (or P=EI) gives is P=I^2 * R. It's coming back to me now.

Ok that makes sense. You can run a headunit into a 2ohm load. Just don't turn it up very loud. I think Infinity is one of the few companies to make a 2 ohm door speaker.

I would get some 4ohm speakers and with sensitivity of 90db+. I've had good luck with boston acoustic with lower power amps.

 

I appreciate all of the responses and I feel like I am back in electronics class. As I suspected, I shouldn't get these Infinity speakers that I have been eyeballing. They are listed as 2 ohm.

I attended some Rockford Fosgate classes back in the early 90's and amazingly, some of this stuff has still stuck with me. I didn't know if things have changed since then.

I also want to say that hooking up a properly crossed-over 4 ohm tweeter and 4 ohm midrange in parrallel will still give a 4 ohm load because they are at different frequecies.

 

This is right off of the Infinity website. What do you audio addicts think?

[FONT=Arial, Helvetica, sans-serif]Plus One® woofer cones - This patent pending technology deliver a cone with more surface area than competing models of the same size. The result is increased bass output and higher efficiency.[/FONT]

[FONT=Arial, Helvetica, sans-serif]• [/FONT][FONT=Arial, Helvetica, sans-serif]True Four Ohms— All Reference speakers feature two ohm voice coils. Original factory-installed speaker wiring in many cars is 18-22 gauge. This wire, and heating in the voice coil when power is applied, increase the impedance “seen” by the amplifier or head unit. The impedance of Reference Speakers has been adjusted to compensate for this increase and can be safely driven by any head unit.[/FONT]

[FONT=Arial, Helvetica, sans-serif]• [/FONT][FONT=Arial, Helvetica, sans-serif]Edge-driven textile dome tweeters - These are not commonly used w-domes, but fully-edge-driven domes like those found in better home audio speakers. The benefit is increased power handling and reduced distortion at high output levels. This technology also allows for better integration with the mid/woofer.[/FONT]

[FONT=Arial, Helvetica, sans-serif]• [/FONT][FONT=Arial, Helvetica, sans-serif]Each Infinity Reference component system includes a pair of laboratory optimized passive crossover netorks that include tweeter adjustment. If the tweeters are located low in the doors or if you are looking for a brighter sound, set the tweeter at +3dB. [/FONT]

[FONT=Arial, Helvetica, sans-serif]• [/FONT][FONT=Arial, Helvetica, sans-serif]To facilitate proper installation and location of the tweeter, each Reference component system includes Infinity's patented I-Mount™ (patent no. 5,859,917) tweeter mounting kit including the Starfish™ OEM adapter. [/FONT]

Ref: http://www.infinitysystems.com/car/...EF&ser=REF&Language=ENG&Country=US&Region=USA

 

I read into this as "impedence rise", this is what the SPL competitors try to overcome in competition. I normally dont knock other products but have you actually heard a set of Infinity speakers?

 

I bought Kappa's front and rear for my Camry about five years ago and I have been very happy with them. I prefere soft dome tweeters to hard materials like titanium. I also have some Polks in my "old" truck that I have had for at lest 20 years that have been really good.

Do you have any speaker sugggestions for me to check out? I have heard good things about CDT.

 

Ok, there has been a lot of information about ohm loads in here but I figured I'd add a few things.

1) Ohm is a measure of impedance. By definition, this is the same thing as resistance. (we cleared that up I'm just reinforcing)
2) The majority of stock amplifiers are NOT 2ohm stable. However, some upgraded stock systems like Bose will run 2ohm speakers. My suggestion is that if the system didn't come with a 2ohm speaker DON'T RUN ONE!

So some of you might be wondering WHY this even matters. Speaker makers use lower impedance loads to improve the amount of power from an amp. Every time you halve the impedance (cut the ohms in half) you double the power. Every time you double the power you get a 3db rise in sound output. What does this mean in practice? You can get a 3db increase by doubling the power (as we said) or by doubling the cone area. Yup, you guessed it, that means that doubling the power will provide output like there are TWO speakers

 

Infinitys dont sound bad, I love them in my house. But I prefer the POLK speakers for my truck!

 

I haven't heard a pair of infinities in a few years so I can't comment on the new stuff. However, I owned a pair of infinity reference components back when I had my prelude years ago and they were BRIGHT as hell! Tweeters that would literally rip your face off.

 

I definatly don't like tweeters that have the potential to rip my face off either. It seems to me that the soft domes have a "softer" sound to them so I am guess that they were some other material.

 

The material has a definite effect on the sound but it's not a determining factor. I had a pair of Focal 165V1 components in my IS300 and they were glorious. The kicker is that they were aluminum dome tweeters.

Go listen to speakers and choose the one you like the most!

 

Ill be running some CDT HD-62Z (Z = a upgraded crossover) got them for 200$ off ebay, if you do go CDT i hear alot of bad things about the crossover model 480 something about the filtering that you get alot of tweeter fatigue

 

Good advice.

 

"An amplifier designed to put out 100 watts into 8 ohms will put out 200 watts into 4 ohms." That depends on the internal resistance of the amplifier and the ohm resistance it was designed to drive. Optimal power transfer is when the load is equal to the amplifier internal resistance. Since most speakers are reactive loads, meaning their resistance varies constantly with frequency and volume, they look like a load that is either pushing back sometimes and pulling away sometimes. Inductance vs capacitance = impedance. Sorta like trying to push/pull a giant mound of jello that is wobbling to and fro constantly. The amplifier would like a nice consistent load like a simple resistor to impart its signal on. The potential problem with hooking up reactive speakers in series is that the amplifier is trying to push/pull the driver of each speaker precisely, while each speaker is seeing the signal thru the other speakers constantly varying resistance. Now you have two giant mounds of jello in series that the amplifier is trying to start/accelerate/decelerate/stop with precision. Some rare audiophile amplifiers have a feedback system to monitor and compensate for the load fluctuations. They sometimes work well, and sometimes just screw up the sound more. If you can imagine yourself trying to push a heavy load back and forth with someone on the other side out of sync with you and someone in the middle working against both of you. For simplicity of controlling each driver, it is probably better to not run reactive speakers in series. Ribbon tweeters may be a different story since they pretty much look like simple resistors to an amplifier. If an amplifier is rated for 4-8 ohms, then that is the ideal max power range. Too low resistance looks like a short and burns them out. Higher resistance is actually easier on the amplifier circuits, but reduces audible power. Sort of like having a 300HP engine and full throttling it all the time carrying the max load vs gently cruising the highway with your groceries.

 

This thread died 12 years ago... 12 years! But no, you had to dig up its grave to post this

 

Even crazier I subbed it a couple weeks ago so I could finish reading it and it’s been hit up twice now.

 

Yeah, as an Electrical Engineer myself I still hear people asking/talking about these same issues. So, since there are people who may be looking at this website for correct info, and are free to read or not read it, I figure 12 years is a long time to have wrong info still posted. IMO, most juvenile purchasers of sound equipment make their decisions based on what their friends buy, how loud it is, and the sex appeal of the brand logos. Does it have a LOT of thump and sizzle that my neighbors can hear from two blocks away? But, for anyone who is a discerning listener interested in fidelity beyond dynamics, understanding the interaction of speaker reactance and amplifier design may be of interest. Those who don't care to understand are free not to read or comment and can opt out of getting notices.

 

So fidelity wise its better to wire the speakers in parallel?
That's what was suggested to do earlier in the thread .

 

The problem with this thread is that it is riddled with misinformation. Also, fun fact, people that wire their equipment into lower ohm loads are not chasing fidelity.

To answer your question, it depends. What speakers are you talking about?

 

Subs . 2 10's to be specific. I'm pretty sure that there single voice coils.

 

I wire subwoofers parallel, but I always buy subs that I can wire at 4 Ohms.