Preamp and receivers are they same?

Wharfedale Evo 4.2

madhurshankar

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Buddy,
Are preamps and receivers same with respect to sound processing? Can any one please help in knowing them. I also have some other doubts and they r listed below.

Difference between Integrated Amps and receivers. Can anyone let me know what will be the minimum cost of matching 5 channel Preamp + 5 channel Power amp for quad 22l2 and Dynaudio. Pal, thanks for considering.

Does Integrated Amp sounds the same as Preamp + Power Amp combo.
 
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venkatcr

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Are preamps and receivers same with respect to sound processing? Can any one please help in knowing them. I also have some other doubts and they r listed below.

There are three stages to sound processing. One is the play of the media whether you use a turntable, a tape drive, a CD, or other devices. The playing devices send the audio signals at very low voltage usually measured in milli or micro volts. This sound signal is taken and enhanced by the next device, the pre-amplifier. The pre-amplifier inputs the sound signal from the playing device, amplifies it to roughly 2 volts, and sends the pre-amplified signal to the next device - the power amplifier. The power amplifier again amplifies the signal by supplying a large current gain and takes it to a level that can drive the speakers attached. This is measured is Watts.

What I have mentioned above refers to a single channel of sound. There is also an additional step of digital to analogue conversion (DAC) that can be done by the playing device, or the pre-amplifier.

In a stereo systems, a pre amp and a power amp operate on two channels at the same time.

In a multichannel systems that is used in movies, the pre-amplifier operates on 6, 7, or 8 (sometimes 12) channels at the same time, In additional the pre-amplifier decodes audio codes held in the DVD Media, and also decodes video signals. To void confusion, the pre-amplifiers used in multi channel systems are called sound processors.

The multi channel sound processor, then sends 6, 7, or 8 analogue pre-amplified signals to the multi channel power amplifier that amplifies each channel separately and sends them to the respective speaker.

A box that contains both the pre-amplifier and the power amplifier in one unit is called an Integrated Amplifier.

An integrated amp that has a pre-amp, a power amp, and a radio receiver is called a receiver. A receiver could be a two channel receiver, or a multi channel receiver. A Multi channel receiver is usually referred to as Audi-Video Receiver or AVR.

Does Integrated Amp sounds the same as Preamp + Power Amp combo.

In the olden days, it was generally believed that combining pre and power amplifiers would lead to cross talk and interference. Audiophiles preferred to keep the pre and power amps separate and connect them through external interconnect cables.

Modern receivers are very advanced units with high levels of protection from all interference. For most budget and mid range systems, it will be difficult to differentiate between separate pre and power amps, and a integrated unit. In the high end, pre-amplifiers and power amplifiers are yet available as independent units. The cost generally doubles or triples when you configure your systems this way.

Cheers
 
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ash147

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Very nicely explained.Pls tell me why a signal is amplified twice,once by a pre-amp and then by a power amp ? why not this job can be done by either a pre-amp or a power amp

There are three stages to sound processing. One is the play of the media whether you use a turntable, a tape drive, a CD, or other devices. The playing devices send the audio signals at very low voltage usually measured in milli or micro volts. This sound signal is taken and enhanced by the next device, the pre-amplifier. The pre-amplifier inputs the sound signal from the playing device, amplifies it to roughly 2 volts, and sends the pre-amplified signal to the next device - the power amplifier. The power amplifier again amplifies the signal to a level that can drive the speakers attached. This is measured is Watts.

What I have mentioned above refers to a single channel of sound. There is also an additional step of digital to analogue conversion (DAC) that can be done by the playing device, or the pre-amplifier.

In a stereo systems, a pre amp and a power amp operate on two channels at the same time.

In a multichannel systems that is used in movies, the pre-amplifier operates on 6, 7, or 8 (sometimes 12) channels at the same time, In additional the pre-amplifier decodes audio codes held in the DVD Media, and also decodes video signals. To void confusion, the pre-amplifiers used in multi channel systems are called sound processors.

The multi channel sound processor, then sends 6, 7, or 8 analogue pre-amplified signals to the multi channel power amplifier that amplifies each channel separately and sends them to the respective speaker.

A box that contains both the pre-amplifier and the power amplifier in one unit is called an Integrated Amplifier.

An integrated amp that has a pre-amp, a power amp, and a radio receiver is called a receiver. A receiver could be a two channel receiver, or a multi channel receiver. A Multi channel receiver is usually referred to as Audi-Video Receiver or AVR.



In the olden days, it was generally believed that combining pre and power amplifiers would lead to cross talk and interference. Audiophiles preferred to keep the pre and power amps separate and connect them through external interconnect cables.

Modern receivers are very advanced units with high levels of protection from all interference. For most budget and mid range systems, it will be difficult to differentiate between separate pre and power amps, and a integrated unit. In the high end, pre-amplifiers and power amplifiers are yet available as independent units. The cost generally doubles or triples when you configure your systems this way.

Cheers
 

venkatcr

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Very nicely explained.Pls tell me why a signal is amplified twice,once by a pre-amp and then by a power amp ? why not this job can be done by either a pre-amp or a power amp

The functions and output of the two are completely different.

A pre-amplifer supplies only a voltage gain of a small amount that is needed to act as an input to the power amplifier. A pre-amplifier does not 'amplify' in the sense we all understand.

A pre-amplifier does a number of things. It accepts signals from multiple sources, switches the input, recognises the signal strength, add a small voltage gain to take the signal to a specified voltage level that a power amplifier can understand. It also, if necessary, decodes the audio signals. Some pre-amplifiers also have a digital input wherein they can accept digital signals from a CD/DVD player. A pre-amplifier is more like a sound processor.

You need high power and a large current gain to drive speakers. A power amplifier does this and nothing else. It takes a single input from the pre-amplifier that is usually 1 to 2 volts. A large current gain is given to the signal (measured in watts) that is required by your speakers.

Cheers
 
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samirarora

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Rough differences between owning a receiver and having separates.

RECEIVER

-Same power supply for the power and pre sections, ie it is shared.
-Since more is put into a single package, manufacturers will use lesser quality of components as compared to dedicated components.
- Receiver also has video processing and a radio tuner, circuits of which are known to interfere with the output signal enough to make a difference
- Is cheaper and requires one shelf on your rack.
- Most receivers if not all, are rated to be used with speakers of minimum 6 ohm impedance, but in the real world , more and more manufactureres are offering speakers of only 4 ohms.. this is no issue , but could be one, if you listen real loud consistently.
- Cheap solution, works well for most if not all, other than of coarse those who want nothing but the best and have the cash to fuel their hobby.

Dedicate pre and dedicated power amp.

-Both will end up having separate power supplies, no cross talk, no power shortage issues.
-No cross talk between pre and power circuits
-Price goes up quite a bit, also extra interconnects are required to be purchased.
-Requires two shelves on your rack.
-A dedicated power amp, will be mostly rated to use speakers of 4 ohms or under, which works well in the real world, as most speakers are rated 4 ohms nowadays.
-This duo combination turns out quite expensive though, with cheaper pre amps being more expensive than the most expensive receivers.


Better receivers on the whole can be used as pre amps, most if not all, have switches to supply pure direct signal from source, which basicaly switches off video circuitry and all other processing by the receiver itself and signal from source goes direct to amplification stage.

best wishes,
samir.
 
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