Amplifiers

[JimPullan]

Dear BStecke,

If you have opportunity, plan a visit to my website, and go into 'Products' and take a look at the various offerings there. For Amps only, check our Sherbourn, they make some very fine, economically priced amps. Also, B&K makes some good amp. All the products on my site link to the manufacturer specifications. If you need additional assistance, just send a 'Private Message' above.

Jim Pullan
Audio Excellence

http://www.AudioExcellenceOcala.com (My website)

Originally Posted by BStecke

The next logical step in my home theater would be to add an amplifier, which I really know nothing about, as far as the home theater environment goes. Car audio, yes.

In looking at some of the major brands (Yamaha, Denon, Pioneer) I'm seeing that most amplifiers are mono or two channel. In my mind, I would need a 5 channel amp, one channel each for F, L, Center, and Surround. I really don't know why they even make a mono amp for a home theater application, unless it would be for an unamplified subwoofer. Maybe I'm incorrect, which, from what I'm seeing in amp selection, I would believe.

Anyway . . . school me on amplifiers! I'm familiar with RMS, Dynamic, etc, etc, so I don't need much info on that. I'm sure there are brands for amps I've never even heard of, which I'm hoping to gain more familiarity with as well.

[JimPullan]

Originally Posted by BStecke

I'll have all Reference series in a week or so: RC62 center, RF82 fronts, RB61 rears, RW12d sub.


My Pioneer receiver does not have the balanced outputs, at least that I am aware of. I'm assuming both ends of the connector look the same. Is this mainly a feature of standalone processors/preamps, or do "all-in-one" AVR's ever include these?

If you are retaining your existing Receiver, to act as your Pre-Amp, and you will use the Pre-Outs to power from external amps, it won't matter if the amp is balanced or unbalanced, there are always gender changers in order to make the handshake of the components. [Jim]

[cam555]

I have also been wondering what kinda amp i should get to power my speakers.

[MatrixS2000]

^ this is a pretty good list of manufacturers to start with. I use Parasound and am very happy with them.

Originally Posted by jdc115

Rotel
NAD
Adcom
B&K
Parasound
Outlaw

[cam555]

would they work good with my speakers???

[btf1980]

Originally Posted by cam555

would they work good with my speakers???

Before you buy a separate amp, first make sure your receiver has pre-outs.

[richteer]

Originally Posted by MatrixS2000

How is this any different that what I posted (other than you adding points on interference which wasn't in the discussion)?

And where was I inaccurate?

I was being pedantic about the high level bit in your post. But otherwise, your description was pretty good.

[richteer]

Originally Posted by MatrixS2000

Clipping is distortion of the amplified signal when you ask your amplifier to amplify a signal beyond what the power supply can handle. Imagine a nice clean sine wave, when an amplifier is pushed to clipping, the top and bottom of that sine wave are clipped off. The signal is clipped because the power supply section of the amplifier (or receiver) can no longer provide enough power to the amplifier section to cleanly amplify the signal.

That clipped off portion basically represents a dc current (like a battery) to the speaker and creates heat in the voice coil of the speaker. Too much clipping and the voice coil overheats and you damage your speaker.

A good rule of thumb to stick by to somewhat protect yourself from clipping is to never exceed 70% on your volume control.

Just adding to Matrix's excellent post: it is nearly always safer to use a more powerful amplifier with speakers than a less powerful one. A more powerful amplifier will play louder before clipping, which means there's less chance of damage to your speakers. Of course, if you crank a powerful amp all the way up, you're gonna fry your speakers n omatter what. :-)

[scarpi]

I have a five channel Sherbourn amp and B&K Reference 30 preamp in my system. I highly recommend them. If you get a powerful amp like the Sherbourn, make sure that your speakers can take that much power (200watts/channel into 8ohms and 300 into 4 ohms). The more power you have, the cleaner the sound is for movies and music. It gives you more dynamic headroom so that you can play it louder before it clips and you run out of power and get distortion. Usually speakers are damaged by an amp running out of power and clipping, not by too much power.
Don

[TENSE]

Originally Posted by MatrixS2000

Ok couple of things:

1 - speakers do not output anything other than sound. So when you read a wattage spec on speakers, they relate to input wattage (the maximum power they can handle) not output.

2 - To answer your question - no you don't need an amplifier if your receiver puts out less power than your speaker maximum. However, if you run your receiver hard (as in close to maximum volume), it could damage your speakers as the amplifier section in the receiver is most likely be clipping. Clipping is what leads to speaker damage.

Clipping is distortion of the amplified signal when you ask your amplifier to amplify a signal beyond what the power supply can handle. Imagine a nice clean sine wave, when an amplifier is pushed to clipping, the top and bottom of that sine wave are clipped off. The signal is clipped because the power supply section of the amplifier (or receiver) can no longer provide enough power to the amplifier section to cleanly amplify the signal.

That clipped off portion basically represents a dc current (like a battery) to the speaker and creates heat in the voice coil of the speaker. Too much clipping and the voice coil overheats and you damage your speaker.

A good rule of thumb to stick by to somewhat protect yourself from clipping is to never exceed 70% on your volume control.

OK BUT YOU KNOW WAT I MEANT ABOUT MY SPEAKERS.!
WELL ANY WAY SO IF MY RECEIVER CAN OUTPUT MORE WATTAGE THAN MY SPEAKERS TOTALL WATTAGE
DOES THAT MEAN I CAN TURN UP THE VOLUME ABOVE 70% RIGHT?

[gearyt]

Originally Posted by TENSE

OK BUT YOU KNOW WAT I MEANT ABOUT MY SPEAKERS.!
WELL ANY WAY SO IF MY RECEIVER CAN OUTPUT MORE WATTAGE THAN MY SPEAKERS TOTALL WATTAGE
DOES THAT MEAN I CAN TURN UP THE VOLUME ABOVE 70% RIGHT?

no

[HDJK]

Originally Posted by gearyt

yes

Really?

Do receivers limit their output so you never run danger of clipping the amp? If not, I would not recommend going much higher than 70% of total power output.

[gearyt]

Originally Posted by HDJK

Really?

Do receivers limit their output so you never run danger of clipping the amp? If not, I would not recommend going much higher than 70% of total power output.

whoops, answered the question backwards...
corrected

Must keep BELOW 70%

thanks for the catch !!

[RUR]

Originally Posted by gearyt

whoops, answered the question backwards...
corrected

Must keep BELOW 70%

thanks for the catch !!

Too late! I just fried my WATT Puppies, based on your advice. My lawyer will be in touch......

[MatrixS2000]

Originally Posted by TENSE

OK BUT YOU KNOW WAT I MEANT ABOUT MY SPEAKERS.!
WELL ANY WAY SO IF MY RECEIVER CAN OUTPUT MORE WATTAGE THAN MY SPEAKERS TOTALL WATTAGE
DOES THAT MEAN I CAN TURN UP THE VOLUME ABOVE 70% RIGHT?

WHY ARE YOU YELLING AT ME?

As others have said...always keep your max volume at around 70%.

[BStecke]

Here's what may be another stupid question . . . the analog outputs that would be used for SACD/PCM/etc. would go to the amp, correct?

[MatrixS2000]

Originally Posted by BStecke

Here's what may be another stupid question . . . the analog outputs that would be used for SACD/PCM/etc. would go to the amp, correct?

Depends on which component you are talking about. It basically connects like this:

SACD player<---analog out--->receiver/processor<---analog out--->amplifier.

Obvious if you are using a receiver you won't have the connection to the amp unless your are using the receiver as a pre-amp only.

[beakergeek]

There are many 5 channel amps but the good ones are not made by any of the brands you mentioned. Rotel, Parasound, Krell are just a few but the best value is Emotiva which is a newer company that boasts audiophile grade at lower prices. Their website has details on their newest 5 channel. Things to look for in an amp are many but a few important ones include: toroidal transformer, power into both 8 ohms and 4 ohms, separate amp sections for each channel, etc. The new 5 channel emotiva is $899 which is the best value you will find in an amp.

[BStecke]

My apologies, I went stupid there for a minute. I was thinking about the analog inputs on the receiver. I'm assuming the analog outs from the receiver that would go to the amp would be similar to the analog ins.

Even better, does anybody know offhand if the Pioneer VSX-91TXH has the proper outputs? I won't be home to check for awhile and Pioneer's website isn't easy to navigate on the iPhone.

Originally Posted by MatrixS2000

Depends on which component you are talking about. It basically connects like this:

SACD player<---analog out--->receiver/processor<---analog out--->amplifier.

Obvious if you are using a receiver you won't have the connection to the amp unless your are using the receiver as a pre-amp only.

[RUR]

Originally Posted by BStecke

Even better, does anybody know offhand if the Pioneer VSX-91TXH has the proper outputs? I won't be home to check for awhile and Pioneer's website isn't easy to navigate on the iPhone.

The spec page and the rear view of the AVR show 7.1 Pre-outs (RCA), so you should be fine.