? 0°/180° Phase Switch ? Amp Classes?

[SubSonic]

Ok well i have a couple questions, first

on Amps, there is a phase switch, from 0°/180° , what does this do, reverse current? or what,

also i know class D are monoblock amps,

but whats the main purpose of the different class's like A Ab Bc De D and etc, and can u really go in detail when explaining..

along with that, when u get a amp with like 3-4 channels, like a 600W4 channel, does it mean u get 600W Rms to every channel, and u can brige all 4 to get 2400W Rms? or what>? please help me out, will very very appreciated, THANKS

and, what does a Low Pass or High Pass do, allow a cut out if it reaches a higher /lower freq? lmk thanks

Edited February 1, 2009 by SubSonic

[SubSonic]

Anybody ??

[capalass23]

Ok well i have a couple questions, first

on Amps, there is a phase switch, from 0°/180° , what does this do, reverse current? or what,

also i know class D are monoblock amps,

but whats the main purpose of the different class's like A Ab Bc De D and etc, and can u really go in detail when explaining..

along with that, when u get a amp with like 3-4 channels, like a 600W4 channel, does it mean u get 600W Rms to every channel, and u can brige all 4 to get 2400W Rms? or what>? please help me out, will very very appreciated, THANKS

and, what does a Low Pass or High Pass do, allow a cut out if it reaches a higher /lower freq? lmk thanks

its changes the frequencys for where ur speakers are like if there on the sides of u put it at 180

[SubSonic]

What?

[Decaf]

Ok well i have a couple questions, first

on Amps, there is a phase switch, from 0°/180° , what does this do, reverse current? or what,

also i know class D are monoblock amps,

but whats the main purpose of the different class's like A Ab Bc De D and etc, and can u really go in detail when explaining..

along with that, when u get a amp with like 3-4 channels, like a 600W4 channel, does it mean u get 600W Rms to every channel, and u can brige all 4 to get 2400W Rms? or what>? please help me out, will very very appreciated, THANKS

and, what does a Low Pass or High Pass do, allow a cut out if it reaches a higher /lower freq? lmk thanks

phase reverses polarity... so it makes the positive negative and negative positive... this can be useful when mounting a sub outside of the box, or inverting it.... it is sometimes use also to correct timing so the substage mixes well with the front stage

just google or wiki class a, b, ab, d... not worth typing it all out

ab is most common 4 channel mid/high amp

class d most common for subs

most companies market max/peak power x 4.... but in cases like a sundown100.4... it does 100w+ on each 4 channels @ 4ohms

rms is what matters, thats the continuout power the amp can create

you can bridge a 4channel into a 2channel, so in the sundown example... it becomes ~320w+ x 2 channels @ 4 ohms

so a sundown125.2 2channel does 125x2 @ 4 ohms, but can also be bridged producing ~400w+@ 4ohms in 1 channel

a low pass filter will only allow the frequencies below the point you set the dial at... so if its at 100hz, the amp will play 100hz and below unfiltered, and depending on the slope(usually 12-24db) will drop off as you go up an octave (if 12db slope and 100hz setting, at 200hz it would be filtered 12db, and at 400hz it would be down 24db)

high pass does the same, but allows only the frequencies above that setting to go unfiltered

[eliassami5]

whats the main purpose of the different class's like A Ab Bc De D and etc, and can u really go in detail when explaining..

when u get a amp with like 3-4 channels, like a 600W4 channel, does it mean u get 600W Rms to every channel, and u can brige all 4 to get 2400W Rms?

I wont get into detail about how all the different classes of amps work but it has to do with efficiency and the number for speakers the amp will be driving.

when you get a 4 channel amp and it says it can do 600W Max, you divide the 600W by 4, so the amp can produce 150W RMS to each channel. On most amps you can only bridge channel 1+2 or 3+4, you cant do like 1+4, so if you bridge the amp at channel 1+2 you get 300 watts rms (each channel is 150w rms so 150+150=300)

[SubSonic]

Ok cool, thanks alot!!!

[Boon]

Classes in a nutshell....

With class A half the output transistors are always turned on (usually biased into being on by being connected to one of the power rails) so the transistor has to work a lot harder to pull down the voltage to create the negative half of the wave (usually they bias the NPN transistors I think)

Results in low efficiency and a lot of heat but a very clean amp.

Class AB is the standard thing for full range amplifiers and cheap sub amps. It uses a combination of NPN and PNP transistors to each push the voltage for half the wave.

Class D uses a pulse width modulated carrier signal in the output section. A very complicated driver circuit modifies the width of the pulses in this carrier signal depending on how much voltage is supposed to be at the outputs. This is because Class D amps use MOSFETs in the output which only have 2 states, on or off. They can't only let some voltage through like a normal transistor.

A series of inductors combines and then low-pass filters the output of these transistors to remove the carrier signal, leaving only the audio signal.

Class D amps are much more efficient (they spend a lot of time in an 'off' state) and can drive lower ohm loads than most other amps. They are also more expensive due to the increased complexity, they tend to be quite noisy amps and they're very tricky to make in full-range so mostly restricted to running subwoofers only.

[MickyMcD]

In addition to Boon,

Class C is a high voltage rectified amplifier that passes the signal down a single wire for broadcast purposes. Class G or H (relatively the same thing) can have any class output stage, but has a multitapped power supply (usually two or three taps) that are used according to demand, and also has transistor 'banks' if the output stage is analogue. The lower the output signal, the less 'banks' are used and a lower amperage transformer tap is used. Higher effeciency than standard supplies and output stages, switching taps can be noisy.

SMP or SMPS amplifiers with a class A, AB, B, C, G, or H output stage use a switching power supply instead of heavy transformers. SMP power supplies are very effiecient and, when coupled with large capacitor banks, allows amplifiers to deliver power in bursts above what the suuply power is.

Class TD from Lab.Gruppen is some funky motherfucking shit that makes most engineers trip balls. A 13,000w dual channel amp from a 2400w power point? You know it.

Cheers,

Mick