Honest answer ...

You don't.

But at least they look pretty

 

A friend of mine at Boston Acoustics did quite a few sound measurements on one of the VP's G35 Coupe and said the Bose system was excellent, although they will still probably change out the speakers. He was really interested in the Infinity's Bose system because I have been forwarding him all of the posts on the Bose system from here. It is a really nice looking system.

On a sidenote, when she pulled her car (2 days old) into the other bay at BA, she parked beside my Z (which is still there being upgraded, but is all in pieces) she said to him "DON'T do that to my car!".

 

Can you please ask your friend what aftermarket speakers are compatible with the Bose system? I was looking at Infinity63.5i for replacing my front 2, but then Circuit City told me that the Bose system is 2ohm and the Infinitys or any other aftermarket speaker is 4ohm, so they're incompatible. According to CC replacing the HU is my only option, but I don't want to do that.

 

My friend is out in California right now "tuning" up Axis Wheel's Porsche 996 for the CES show in Vegas (he "insisted" that he really needed to drive the car to make sure the sound was accurate, so he had it all day yesterday-tough job!). In any event, in a brief conversation he mentioned that the only "real" problem occurs if you DROP the OHMs, so going UP from Bose's 2 OHMs to Infinity's (or ahemmm BA's) 4 OHM would not be a problem. He did mention that the equalization out of the Bose HU unit may change the characteristics of the speaker slightly, but most Bose speakers are usually "flat" anyway so the Infinitys probably wouldn't (noticeably) suffer. Hope that helps (and I hope I got that right...).

 

If you go from a 2ohm to a 4ohm speaker and keep the same amp, you won't be able to reach the same volume levels as you did before. For example, if you usually listen at a volume level of 15 with the stock stuff, you might need to turn it to 25 to get the same loudness with the 4 ohm speakers. I'm just pulling those numbers out of nowhere, but there will be a difference.

Also, I measured the resistance of the Bose sub and it was closer to 1 ohm. I didn't measure the other speakers.

JL

 

The real problem is that you may be overdriving the amp if you don't deliver a 2ohm load to the amp. Aka, working twice as hard for half the result type of scenario.

 

No, not really. You will overdrive the amp if you use speakers (or a wiring pattern) with less resistance (measured in ohms) than the amp is rated for. More resistance will just produce less volume because the amp will not be able to supply the same wattage to the speakers.

Voltage stays the same. So as resistance goes up, amperage goes down. Watts equals volts times amps. So you put in higher resistance speakers, the amp can't push the same amount of amps with the same voltage, so wattage is reduced.

Now if you reduce the resistance, the amp is suddenly passing more amps than it was designed to, and it overheats and/or possibly fries internal components.

But the end answer is you should match the speakers to the amp to keep everything working happily together. You'll get sound, no argument there, but the system as a whole is not going to be optimized.

JL