What does MOSFET mean

 

New member
Username: Hbguy

Post Number: 6
Registered: Nov-04
I am curious to what MOSFET means. Such as a digital amp with a MOSFET power supply. Would these be considered a b/d amp?
 

New member
Username: Terminatermule

Australia

Post Number: 1
Registered: Nov-04
not sure what class it would make them but the MOSFET part of the description is the type of power supply the amp uses. It stands for Metal Oxide Semiconductor Field-Effect Transistor, they are common now as the most efficient of the cheap power supply systems, true digital amps use a different type of pwer supply and are alot more efficient, i think these are class D amps but i may be wrong

Cheers
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 5664
Registered: Dec-03
MOSFET just refers to the circuit topography for the amplifier's power supply. This can be in reference to both class D and AB amplifiers.
There is no truely digital amplifier, just for reference. A class D amplifier samples the input signal at a high sample rate, then reconstructs the signal at a higher power/amplitude at the output stage, but technically, the amplifier is still an analog device as the output stage is still analog as are the speakers connected to the amplifier.
 

Anonymous
 
Why does an amp need to sample the signal? Can't it use the whole signal? And no I don't really know what I am talking about here.
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 5714
Registered: Dec-03
hehe I can tell :-)
think of it like this..
the original signal is analog (RCA lines) much like a singer with a mic.

for the signal to enter the digital realm, it has to be sampled at a high rate and converted into 1s and 0s so the signal can be manipulated digitally.
after it's been processed, amplified, etc, the signal needs to be converted back into an analog waveform so it sounds normal when the signal is pumped into the speakers as an AC sinewave via the voltage coming out of the amplifier's speaker wires.

look at any music CD, and you'll see another example of an originally analog recording (most times, when they're marked ADD or AAD) that's been sampled and converted into a digital format.
In order to convert it back to analog, your CD player has "DACs" which are digital to analog converters. This will get you more into learning about oversampling, 1 bit linear or multi-bit DACs, etc.. but in short, the only way to make an analog signal digital, is to sample the original signal, and convert it into the closest approximation in a digital means.
you'll always lose just a little bit of the original quality by converting to digital, which is one reason some of the old school folks still prefer vinyl to CDs.
meh.. I could babble about digital vs analog for hours, but I'll quit boring you.
 

New member
Username: Hbguy

Post Number: 7
Registered: Nov-04
Thank you for all the replys. I am new to the car audio world, wanting to know how all this works. You have been a good help. Thanks agian
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 5813
Registered: Dec-03
www.bcae1.com
an amazing resource for the new car audio fan.
www.the12volt.com is good as well.
teamrocs.com (I think) and jlaudio.com both have terrific FAQ sections too
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 2622
Registered: May-04
Vinyls do sound nice :-) Most vinyl recordings were recorded with tube electronics, which IMO sound better. I think that makes a big difference when you get a tube overload compared to a transistor overload
 

Gold Member
Username: Glasswolf

NorthWest, Michigan USA

Post Number: 5858
Registered: Dec-03
I wrote a whole thing about tube vs SSA.. I think it's in the amp specs faq on my site lol
yeah odd ordered harmonics versus even ordered and such makes a big difference, but again, it depends what you're after.. warmth, accuracy, etc.

I like the accuracy of a class A amp and it's ability to handle the harsh demands of larger speakers like the ESLs, but for smaller speakers or guitar amps, tubes sound great.
 

Gold Member
Username: Jonathan_f

GA USA

Post Number: 2629
Registered: May-04
Yeah, I mainly prefer tubes when signals are likely to be overdriven, such as hard guitar, huge cymbal crashes and drums etc. Their clipping is just much softer. Tube preamps and SSA amplifiers seem to work really well together IMO.
« Previous Thread Next Thread »



Main Forums

Today's Posts

Forum Help

Follow Us