pre-amps

[shawtyjmp]

what is the difference in a pre-amp or buying a regular amp for home speakers? and what is the pre-amp out on the back of my receiver for??

 

[anamorphic96]

The pre outs on the back of your receiver are for upgrading the amplifier section in your receiver to a larger or better amplifier. Or it can be used to hook up a subwoofer.

A pre amps main purpose is to take the low level signals coming from your cd player, tape deck or DVD player and boosts them to an acceptable level that the amplifier can drive. This is why a pre amp has outputs. So an amplifier can be hooked up. It also serves as a switching device so you can use multiple sources. It also controls the volume of the system.

Hope this helps.

Glenn

 

[Az B]

A pre amp, as the name implies, occurs in line before the amplifier. In the case of modern electronics, it's where signal processing and switching occurs. The amp does nothing more than amplify the signal.

The preamp out on your reciever is the line level unamplified signal from the pre amp section of your reciever. Even a reciever has a pre amp stage and an amplifier stage.

Why choose a reciever over a seperate pre amp and amp, or visa versa? It all comes down to economics. It's generally cheaper to house the pre amp and amp sections in one chassis. The drawbacks of a receiver are mostly based on the compromises of the design. Seperate pre amps tend to put performance first.

 

[Rip Van Woofer]

All audio "power" amplifiers (the ones that actually drive your speakers) need a pre-amp to boost the very low voltage "line level" signal from your sources (like tuners and CD players) to a level where it is usable by the power amplifier. The preamp includes the volume controls, balance and tone controls, etc. Exactly why this is necessary is beyond me even though I've read "simple" explanations; ask an electrical engineer!

The preamp out jacks on the back of a receiver allow you to bypass the receiver's built in amp if you wish to use a more powerful amplifier, while retaining the control and processing functions of the receiver's preamp, tuner, and digital processors.

Some audiophiles prefer separate preamps and power amps - this tends to be more expensive. In the Olden Days there was a case to be made for the inherent electrical and sonic superiority of this arrangement but no longer, IMO. Flexibility, the ability to use monstrously powerful amplifiers beyond what is available in even "flagship" receivers, or do use biamped speakers with active crossovers and, frankly, a bit of snob appeal are the main advantages nowadays (again, IMO).

So it comes down to: do ya want 'em in one box, or in separate boxes?

EDIT: Holy cow - three of us answered almost simultaneously!

 

[av_phile]

Most DVD and CD players have voltage output levels of 2V RMS - enough to drive a power amplifier directly, assuming the player has an output level control that can go to minus infinity or total silence. A lot of purist audiophiles who only have only ONE source with variable output go this route.

Some preamps are UNITY gain pre-amps that do nothing to increase the signal strength of the line level signals from sources, except to attentuate, provide for multi-source selection and compensate for insertion losses. Some don't even compensate for insertion losses. Again, many purist audiophiles use UNITY gain pre-amps that only does signal attenuation and source selection.

If I recall tight, there's a power amplifer (could be an Aragon) with a built-in input level control that is advertised as not needing a preamp. I could have sworn it looked like an integrated, but the brochure said it isn't.

 

[Yamahaluver]

The Yamaha B/M/MX series amps have always had built-in input level controls to regulate volume without a pre if neccesary, Yamaha, Accuphase and other CD players have had very good analog volume controls on them negating the need for a pre if CD is your only source.