Speaker Sensitivity?

[bjwest9738]

I have been some research on this before I decide to buy some new components for my truck and I was just wondering about the db rating for speaker sensitivity. I understand that the higher the rating the more efficient the speaker and the less power it needs but I was wondering if there is a noticable difference between a speaker with a rating of 87 db vs a speaker with a rating of 93 db?

Thnx

[frojoe]

Yes, because the decibel scale is logarithmic, 10 decibels is equivalent ten times louder. For sensitivity this means that a 3 decibel increase in sensitivity is equivalent to doubling amplifier power. So unless your pouring power in or there is a large sq difference, go with the 93's.

Edit: not all companies will measure sensitivity using the same test, and often cheaper brands will use a test that exaggerates sensitivity. Check that both speakers you are comparing were measured with the same test.

[bjwest9738]

the 2 sets of components im comparing are the alpine type r's at 87 db vs the infinity 6020cs (i think thats it) at 93 db. which u think is better?

[frojoe]

how much power(rms) are you planing on feeding them and what are the rms rating of each?

the thing about sensitivity is that usually cheaper speakers that are designed to be played on less power will be more sensitive. these speakers will sometimes lack the sound quality or power handling of less sensitive speakers. that's certainly not a solid rule, but a guideline.

[bjwest9738]

the alpine's rms is 8-110 with a peak of 330 and the infinity's rms is 2-90 with a peak of 270. my head unit puts out 18 watts rms but i plan on eventually gettin an amp to power them

[frojoe]

well, those specks are very similar, so assuming they both sounded equally good, go for the infinities. The higher sensitivity will help get you higher volume with the limited power from the hu, and get you more bang for your buck when you get an amp. That said, read the reviews because the sound quality is probably the most important thing. I have 4 type-r's I'm very happy with, but I have an amp so the sensitivity is less important. So, go with the ones that sound best to you, and if they sound the same get the infinities.

[bjwest9738]

i read that the alpines are a real power house and meet their true potential with a amp powering them. the price difference is about $90 so ill prob go with the inifinity's. thnx for all ur help

[touringcamry]

If you have the oppotunity to listen to these speakers, do so first. Both might have good reviews, but in the end it depends on whether you like them or not because they probably won't sound the same.

I don't know what the tweeters on the above sets are made of, but if one is metallic and the other is silk, they will have very different sound.

[bjwest9738]

i did some more research and noticed that the infinitys are like 2.6 ohms and the alpines are 4 ohms, with this new info which do u think is the best?

[frojoe]

If your head unit, and the amplifier you are going to get are 2 ohm stable, then this is even better for the infinities. 2 ohm stables mean they will work down to 2 ohms, rather than 4 ohms which is more normal for car speakers. Not all amplifiers are 2 ohm stable, but many are, and you will see it in the specifications. You will also notice that the same amplifier will output more rms power at 2 ohms than 4, meaning more volume from the same amplifier. This is because of ohms law, where V=IR. V=voltage, I=current, R=resistance. As this equation shows, at a given voltage, current is inversely proportional to resistance. So since the resistance in ohms is lower in the infinitys, more current flows through them. So again, get whichever ones sound the best to you, but if they sound the same, the infinitys seem like the better choice, assuming your HU is 2 ohm stable, and when you get an amp down the road it is 2 ohm stable as well.