amp question (1 Viewer)

[Matt Weldy]

was is the difference in pre amp and a seperate amp. I know this is basic. But I have always used what was in my receiver to drive speakers. And now I am thinking about a higher end receiver and some need amps to run the extra speaker channels and I am a little fuzzy on this whole seperate deal.

 

[RobertCharlotte]

See if this link (which I found by looking for "preamp" in the Home Theater Primer) helps:
http://www.hometheaterforum.com/htfo...282#post512282

 

[Bill_Weinreich]

Hey Matt.

A preamp is basically a low power amp use to bump a signal from a different source so that it can be used by the processor. It isnt in itself powerfull enough to drive loudspeakers. Thats where the power amp comes in. Its higher power is what is needed to push those cones.

If you are looking for a newer reciever, most wont require you to add amps to run the 5.1,6.1 etc. Unless of course thats what your looking for. Then you might lean towards the pre/pro set up. There you have your sources run into the preamp/processor than those output run to the seperate amps. A bit more $$$$ though.

Bill

 

[Wayne A. Pflughaupt]

Matt,

Bill is on the right track with his description of a pre amp, but there is much more.

Any system has a pre amp and amplifiers. In a receiver both are housed in the same chassis. With separates, the pre amp is in one chassis and the amplifiers in another.

The pre amp is the control center of any system. Connections for all components are made to the pre amp (or pre amp section of a receiver). It is the pre amp that selects what signals go to the video monitor and power amplifiers. Although it theoretically can be handled outboard, Dolby Digital processing and D/A conversions are typically handled by the pre amp. The pre amp also includes any basic equalization functions, like bass and treble controls. The L/R balance is controlled by the pre amp, as are the other respective speaker levels.

The last thing “in line” in the pre-amp is the volume control, which sends whatever selections, processing, EQ etc. that has been performed upstream on to the amplifiers

Regards,

Wayne A. Pflughaupt

 

[Vince Maskeeper]

Matt,
The explanations above are excellent. You might want to also read other recent topics on amplifiers and preamplifiers:
http://www.hometheaterforum.com/htfo...threadid=52766
http://www.hometheaterforum.com/htfo...threadid=47952
http://www.hometheaterforum.com/htfo...threadid=41187
http://www.hometheaterforum.com/htfo...threadid=39558
http://www.hometheaterforum.com/htfo...threadid=44227
http://www.hometheaterforum.com/htfo...threadid=41917
http://www.hometheaterforum.com/htfo...threadid=48707
http://www.hometheaterforum.com/htfo...threadid=53195
-V

 

[Ted Lee]

i always thought the pre-amp was "passive" with no amplification of any sort???

 

[Vince Maskeeper]

i always thought the pre-amp was "passive" with no amplification of any sort???

Close call- technically, the preamp stage can attenuate the signal slightly upward or downward if it includes the volume stage (which most so). So it's not technically an "amplifier" in the strictest sense, it can boost the signal slightly, so what is above is technically correct.

-Vince

 

[Ted Lee]

thanks vince! never really thought of a pre-amp in that way, but i suppose it makes sense.