A salesguy told me that all OEM head units are custom EQed for OEM speakers, which is how they get away with using the cheapest possible OEM speakers and also why changing out the OEM speakers without changing out the OEM head unit will never give you really good SQ.
I thought he was just trying to weasel his way into a bigger sale, until a few days ago when I had the OEM coaxials on my 04 Camry replaced and saw that they were in fact full-range speakers, no tweeter. Now I am wondering if maybe he wasn't pulling my leg, because if run an unfiltered full-range signal into an obviously cheap one-way speaker wouldn't it sound REALLY bad?
On the other hand if most carmakers' OEM stereos and speakers are chosen with lowest possible bottom line in mind, wouldn't putting an EQ in the OEM head unit increase costs?
Just curious what you guys think.
I put in a PPI PCX-480 so plenty of power now and definitely sounds much better than before.
An EQ is adjustable...so I wouldn't necessarily call it that. But they do, however, adjust the output for better sound in combination with OEM speakers.
So...the guy wasn't telling the truth. The reason the OEM headunits sound awful with aftermarket speakers is because they have extremely low RMS power output. I believe it's around 7-15w RMS on most.
many factory stereo systems have a preset EQ curve to compensate for the car environment and the speakers that go with the system, yes. That's one thing the JL Audio CleanSweep does. It de-compensates those curve settings to give a flat signal output without any factory curve settings to mess with the SQ when using a factory deck with an aftermarket stereo system.
Many OEM radios are also designed to work with only the factory speakers byu using very strange impedance ratings, such as 10 ohm speakers. you switch to a normal 4 ohm speaker, and you end up blowing the amplifier circuit in the factory radio or you jsut get a horridly distorted sound due to the internal amp being driven to clipping at barely audible volumes.
> The reason the OEM headunits sound awful with aftermarket speakers is because they have extremely low RMS power output. I believe it's around 7-15w RMS on most.
I agree that 7wpc would be horrible but 15wpc is not that bad considering that most aftermarket HUs don't have more than 18-25wpc anyways...and a 10wpc difference is really less than 2db in real life. I'm sure there are a lot of other reasons the OEM HUs don't sound so great though.
> Many OEM radios are also designed to work with only the factory speakers byu using very strange impedance ratings, such as 10 ohm speakers.
Weird thing is, I noticed that the rear deck speakers said "5 ohms" yet the front speakers said "4 ohms."
Would it be safe to say that when using a line output converter to connect the OEM HU to a 2-ohm stable amp that has its own adjustable crossovers, that I am able to mostly neutralize those OEM handicaps?
I have been noticing after the amp and speakers were installed that when I step on the gas pedal to accelerate, there is a very faint humming sound (haven't pinpointed the exact source yet) that reminds me of a jet engine.
Did look at the JL Clean Sweep, $400 holy cow...I could get a very nice aftermarket HU with installation for that kind of money!