2 ohm vs. 4 ohm and Infinity

[fliptwister 10+ year member]

I'm setting up the car with a new system and I ordered Infinity Kappa 652.9i for the rear speakers and a MB Quart DSC 480 amp. The speakers have power handling of 75 watts RMS and have 2 ohm impedance. The amp is rated 80 watts x 4 at 4 ohm and 160 watts at 2 ohm.

I'm now second guessing my decision to have 2 ohm speakers. I have been reading that SQ is better with 4 ohm. How big of a difference is there? Sound quality is more important to me than loudness.

I have not bought the 6.5" components for the front yet (I was planning on using my old set until I get new ones). Should I stick with Infinity (Kappa 60.9cs) or will I be better with another brand (and at 4 ohm)? My budget on both front and rear speakers is $250.

Thanks!

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[gunz4me2 10+ year member]

Don't worry about it because Infinity LIES about the 2 ohm rating. Ever wondered why they are still 4 ohm compatible if they are true 2 ohm drivers?

Look at the DC resistance on a 682.7cf that was rated to be 2 ohms. IMHO, the DCR should be more like 1.6 ohms if this were a true 2 ohm driver!

ETA: I do want to warn you that the tweeters on most Infinity Kappa speakers are HARSH! Because of that reason alone I would recommend another component set for the front..... Something like **THIS**

 

[fliptwister 10+ year member]

gunz4me2,

So what ohm would you guess the Infinity speakers are running at?

I did a search and there was a lot of people talking about the harsh highs with the Infinity speakers. I wish I did search here before ordering...I wonder what Sonic Electonix return policy is...

That Precision Power looks like a good choice. I have seen other threads recommend Alpines at that price as well. The type S is rated 80 watts RMS (4 ohm) and the type R is rated 110 watts RMS (4 ohm). The amp I bought is only 80 watts RMS at 4 ohm. If I go the Precision Power or Alpine route will the amp I ordered be adequate?

Thanks!

 

[gunz4me2 10+ year member]

If I had to guess, I would say the Infinity drivers are 3 ohms nominal and by the time you factor in resistance from 16 to 18 guage speaker wire, you are right at 4 ohms.

As for power, you would be hard pressed to tell the difference between 80 watts RMS and 110 watts RMS. If you are looking to go the Alpine comp route, I would highly recommend you go with the Type R comps over the Type S. IMHO the Type R components have a much smoother midrange response whereas the Type S comps are a wee bit dirty. If it wouldn't be for yet another harsh tweeter, I would recommend the Phoenix Gold RSd 6.5" components. Don't get me wrong, the woofer is great, but, I don't care for the PG tweeter that comes with that component set.

 

[fliptwister 10+ year member]

gunz4me2,

I have no problem going with the R, I just thought the amp I ordered will not be optimum with those speakers. I thought the rule of thumb was to have the amp twice as powerful as the speaker. Will the amp I ordered be able to power the R's well?

thanks!

 

[gunz4me2 10+ year member]

gunz4me2,
I have no problem going with the R, I just thought the amp I ordered will not be optimum with those speakers. I thought the rule of thumb was to have the amp twice as powerful as the speaker. Will the amp I ordered be able to power the R's well?

thanks!

That MB Quart amplifier should power a set of Type Rs just fine.

 

[hockeytoker 10+ year member]

i heard comps that are 2ohms sound like sh!t

 

[blazeplacid 10+ year member]

resistance has nothing to do with sound quality

a 2 ohm driver sounds the same as a 8 ohm

its the signal source that changes the way it sounds

8ohm usually sounds "better" because they are used in home applications and have a much better power source.

 

[hockeytoker 10+ year member]

gotya. i had no clue if that was true or not i just read it on a dif thread.

 

[ironchef b 10+ year member]

I sure hope u can return the infinity. As someone previously stated, it's very bright and midbass is practically non-existant. Kappa's was my first set and have moved on to Rainbow Germs and i'm glad i did.

 

[RJesus 10+ year member]

resistance has nothing to do with sound quality
a 2 ohm driver sounds the same as a 8 ohm

its the signal source that changes the way it sounds

8ohm usually sounds "better" because they are used in home applications and have a much better power source.

Lower ohms have a higher rate of distortion.

Or at least thats what Morels multimillion dollar research team concluded.

Maybe they're just saying that so they can sell more 8 ohm tweeters, who knows.

 

[kkreit01 10+ year member]

I have Kappas in my truck. I bought them on clearance. I can't wait to get rid of them. Your ears will be bleeding after 10 minutes. I typically like bright highs, but "harsh" is an understatement. I much prefer the sound of Polk DBs vs. Kappas. I much prefer the sound of the PG Rsd coaxials in my other ride (at about 1/4 the price of Kappas).

 

[fliptwister 10+ year member]

I got the stuff today including the Kappas. I will return tomorrow. I'm leaning towards replacing with the type R. I'm also considering the Hertz ESK 165 (for front) and ECX 165 (for rear) as well but it is a bit more money...

 

[hockeytoker 10+ year member]

I got the stuff today including the Kappas. I will return tomorrow. I'm leaning towards replacing with the type R. I'm also considering the Hertz ESK 165 (for front) and ECX 165 (for rear) as well but it is a bit more money...

dont waist ur money on a rear stage. just buy a front stage an amp em. the type r's get loud but i would recommend these.

http://www.woofersetc.com/p6201/CTX65CS--Image-Dynamics-65%22-Component-Speaker-System.htm

i no ppl that are givin these 400 watts each an there takin it like a champ

 

[fliptwister 10+ year member]

dont waist ur money on a rear stage. just buy a front stage an amp em. the type r's get loud but i would recommend these.
http://www.woofersetc.com/p6201/CTX65CS--Image-Dynamics-65%22-Component-Speaker-System.htm

i no ppl that are givin these 400 watts each an there takin it like a champ

I need to do my rear stage. This is a family car (Subaru Forester) with my kids or friends sitting in the rear seats. I'm also only going to have a small sub, I can't take up a lot of space. Those CTX65CS speakers do look like a good option. I wonder how those would sound in front with Alpine coaxial 6.5 type R in the rear...