Is it true what polk and infinity say

[ccapital83 10+ year member]

These companies claim it's safe to run on head unit power even though they run at 2.7 ohms how can that be I was always told it would over stress a head unit. Anyone had those speakers and had any issues?

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[Louisiana_CRX 5,000+ posts]

These companies claim it's safe to run on head unit power even though they run at 2.7 ohms how can that be I was always told it would over stress a head unit. Anyone had those speakers and had any issues?

Its all in the suspension...

 

[ccapital83 10+ year member]

What do you mean by that

 

[garychoffmann 10+ year member]

2.7 is the resting imedance. The speaker really does not stay a 2.7 ohm load. It is safe

 

[Louisiana_CRX 5,000+ posts]

2.7 is the resting imedance. The speaker really does not stay a 2.7 ohm load. It is safe

this

 

[ccapital83 10+ year member]

Ok good does that mean there is no chance they would be any louder than 4ohm speakers? I was hoping with there 2.7 ohm and 95db rating they may be more efficient and a little louder but sounds like maybe that won't be the case?

 

[trumpet 5,000+ posts]

The thought process behind this is the factory speaker wires will almost certainly be used when upgrading speakers. As the speaker wires warm up with music playing the impedance will rise, just like what happens to the wires in the speaker. Impedance also changes greatly within the speaker. It is never "sitting" at 2 ohms for very long, so there is little risk of overheating the radio.

Polk, JBL and Infinity all have speakers that are less than 4 ohms. These are companies with in-house engineering and they definitely know what they're doing. It is very possible these speakers will sound a little louder.

 

[ccapital83 10+ year member]

I really appretiate the responses my hope is that getting one of these 2 ohm and more efficient speakers will be some kind of louder than stock paper speakers.

 

[n2audio 5,000+ posts]

I don't like the idea of a 2 ohm speaker on a head unit even though JBL/Infinity etc say it's ok.

The fact of the matter is a HU's internal amp is already at its limit driving a 4 ohm speaker.

If you've ever felt the face (or even worse, the back - heat sink area) of a head unit that's powering 4 speakers directly it gets VERY hot.

If the resting resistance of a speaker is less than the typical 4 ohm speaker it's not exactly a stretch to assume its operating impedance is lower as well.

Lower impedance means more current demand. More current demand means even more stress on an already over-worked internal amp.

Since the amp is not able to produce more power (already being at its limit) with the reduced impedance there is no chance for louder speaker performance.

I think the selling point for these speakers is that they get more power out of an EXTERNAL amp, but in an effort not to turn away a possible sale to someone using head unit power, naturally, they're going to tell you they are perfectly compatible with a head unit.