I have a Pioneer HU which has the Mosfet built into it. Printed on the HU is "MOSfet 45X4". Is this Mosfet some sort of amplifier? Would this "45X4 MOSfet power" be the same as having a 4 channel 45x4 amplifier in the car? Or would i be wasting my money to buy a new seperate amp? TIA

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Agron
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The MOSFET 45x4 is the maximum output. The RMS is probably somewhere around 15w per channel. Unless you are running POS speakers then I would recommend a high-quality amplifier.

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by ss109:
The MOSFET 45x4 is the maximum output. <HR></BLOCKQUOTE>

MOSFET is the type of output stage in the
amp - (MOS FET is a type of high power
transistor). I would imagine 45*4 , as SS109
says, is 4 channels of 45 watts peak ..

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Agron80:
I have a Pioneer HU which has the Mosfet built into it. Printed on the HU is "MOSfet 45X4". Is this Mosfet some sort of amplifier? Would this "45X4 MOSfet power" be the same as having a 4 channel 45x4 amplifier in the car? Or would i be wasting my money to buy a new seperate amp? TIA

<HR></BLOCKQUOTE>The Japanese tout MOSFET transistors in all their amplifiers because they are cheap to produce. If you had an opportunity to compare the sound of an American amplifier against a Japanese one you would understand why all American made high end home audio and better car audio use BIPOLAR transistors in their output stages. Mosfets are ok for pre driver but not the best sound as output transistors.

The MOSFET 45 in a head unit is not the same as what you will find in most quality outboard amplifiers. These head units do not have a dc-dc converter, therefore you are still working with about 12v thoughout all stages. Actual output power is around 18watts RMS (RootMean Square).

One advantage that the MOSFET 45 head units have is that they will operate at a lower impedance than a regular head unit, and they come with a built in subwoofer crossover, although I would not recommend driving a subwoofer with a head unit.

MOSFET's (Metal Oxide Semiconductor Field Effect Transistor)is a type of device that offer many advantages over Bi-Polars. Price is generally not one. They operate at a much higher speed than does a Bi-Polar, thereby enhancing the upper octaves and clarity of musical passages.

MOSFETS are not subject to thermal runaway as is a Bi-Polar, therefore require less current regulation, and are capable of much higher current delivery (vs comparable size device)
The Bi-Polar is a fine device and is used in many top qualilty amplifiers, as are MOSFETS.

I a similar pioneer cd player, nothing to fancy, but the RMS for that radio is 22Watts, I did notice a little difference from the old Clarion cd player I had with 15 watts RMS.

I not an EE, but I bet an external amp cannot be compared with the little unit in the radio.



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'86 300E
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