More power to a receiver.

[bbaisw]

I have a Yamaha RX-V1400 receiver hooked up to my Klipsch speakers. In the manual it talks connecting to an external amplifier. I thought you had to have a separate amp/tuner to do that.

My question is can I add more power to my receiver by using these pre-out jacks on the back of my receiver, and if so do you have any opinions on what kind of external amplifier to buy.

Thanks a lot,

C.S.

[Daddy Dee]

Hi Clark,

Welcome to the forum. Yep, your receiver would have the capability to use the preamp section to drive another power amp and it would work with any power amplifier or even another receiver with power amp inputs.

I've read a review of this receiver, which was favorable and notice that it is rated at 110 wpc. This would be ample power to drive the Klipsch speakers I have heard. My experience is not exhaustive, and there may be some amp/speaker combinations at are more complementary than others. However, I'd think it is safe to say that driving an alternate power amp in your system would be quite unlikely to be an improvement.

Just a couple of questions which would provide helpful info for forum members to consider in the light of your question. Which speakers are you currently using? What source, CD or other are you using? And, what does the setup sound like to you right now. If your question comes from some dissatisfaction with the sound result, there may well be some things you could do to have results more to your liking. This is a great place to get some help in that order, if needed.

[bbaisw]

I have RF-5's for the front, 4 RF-35's for the back and rear, KSW-12, and a RC-35 which I might upgrade to a RF-7.

I have a progressive scan DVD/CD player, and listen to some stereo and digital cable radio.

The home theater sounds really good. However, the 2 channel stereo from the RF-5's don't seem to really have the power I thought they would.

Thanks again,

Clark

[Tomski]

In addition to what DD said,remember that a 100watt amp compared to a 200watt,the 200watt will not be twice as loud but only 3db louder,it will be noticable but every doubling of power only adds 3db.

You will have to decide what amp is best based on your speakers,your volume preference,and your amount willing to be spent.

Look for a amp that is at the least rated full power at 20hz-20khz

into 8ohms,the prefect amp spec will double its power into 4ohms and then double again into 2 ohms,

If you cant afford that type of amp look at the point at which a amp brand breaks away from the ideal amp model.

Hope this helps!

Tomski

[ben.]

----------------

On 12/5/2004 3:48:33 PM tomski wrote:

In addition to what DD said,remember that a 100watt amp compared to a 200watt,the 200watt will not be twice as loud but only 3db louder,it will be noticable but every doubling of power only adds 3db.

A 3dB increase is twice as loud. It's just not what most people might expect from a doubling of SPL.

[theryugobuddy]

A few years ago, I used the pre-outs on my Yamaha 85 watt receiver with an Adcom 100 watt amplifier, and the difference was dramatic. Much more depth to all music, especially rock. Thing is, my curiosity about separates was aroused, so I got a B&K preamp off eBay, and that really improved the sound---the Yamaha went in to my small office at home.

I eventually replaced even the Yamaha in my office with separates because the sound quality is so much more musical -- And I sold the Yamaha for the cost of the new ( to me) amplifier!

Separates are the way to go, and the cost of used components on eBay/Audiogon make it a no-brainer.

That said, the Yamaha works rather well as a preamp to an amplifier, its like having the convenience of the receiver with improved sound. Spend some money on good interconnects between them--its worth it--

[DrWho]

----------------

On 12/5/2004 3:28:40 PM bbaisw wrote:

The home theater sounds really good. However, the 2 channel stereo from the RF-5's don't seem to really have the power I thought they would.

----------------

If this is the case, then I might suggest tweaking your speaker location. I know aesthetics are a factor, but ignore that for now and see if you can't get the "power" you think they should have simply by moving your speakers around. Because our rooms are small and closed, there is a lot of cancellation happening as the reflections off the walls interact with the main source. Moving our speakers around changes the sets of cancellations we hear (hopefully resulting in a flatter frequency response). Increasing amp power is only going to increase the magnitude of the cancellations...effectively resulting in no improvement. Increasing amp quality is another issue (not all watts are equal). One other fun thing to do is play some music and walk around the room...notice how different everything sounds (especially in the corners).

[Tomski]

A 3dB increase is twice as loud. It's just not what most people might expect from a doubling of SPL

I probably chose the wrong way to state that,but I wanted to make the point that the difference between say a 100wpc verses a 110wpc would probably not be a huge difference

Thanks for clarifiying that

[Tomski]

This is what I wanted to say but some people have probably had their fill of all things Harman.

http://www.harmanaudio.com/all_about_audio/powerratings.asp

Tomski

[dougdrake]

I believe an increase of 10db is generally perceived as being twice as loud. It takes roughly twice the amplifier power to yield an increase of 3db. Thus, to double the perceived volume takes about 10x the power.

WRT to using outboard amplification, it's not just about power. I added a 200wpc Acurus to my setup instead of letting my Denon AVR3300 (105wpc) run my mains and I (and my wife) immediately noticed strong, more controlled bass. I'm sure there were other subtleties, but that was the one that "jumped" (so to speak) out at us.

[Colin]

excellent article!

I think he wants more punch, most young guys do, maybe a sub woofer?

[minn_male42]

One other factor that many people overlook in this discussion is that most receivers can handle efficient speakers without a problem if the impedance stays pretty close to 8 ohms throughout the frequency range.....

i know that my KLF-30's for example have a very low impedance dip in the lower frequency range (it drops to about 3 ohms or so).....

receivers cannot do justice to a speaker with that type of variable impedance plot.....

my KLF-30's sound much, much better with my carver professinal ZR1000 digital amplifier (225 watts per channel) compared to the internal amps of my pioneer elite 55txi receiver.....

[michael hurd]

Here's how you add more power to your receiver....

[dodger]

In logarithym as applied to audio physics, a 3 db increase is what the average person will notice as a volume change. So to get a noticed volume change one has to double the power:

in watts: 1,2,4,8,16,32,64,128,256, etc., it is not a doubling of volume or sound pressure level, SPL.

Some with excellent hearing may perceive an increase in sound at 2 decibels. The average is 3 db.

Thus a 128 watt amplifier is not twice as loud than a 64 watt, it will have more headroom but only a a small perception louder.

By adding more power without doubling the amplifier wattage, you gain headroom before clipping.

To double the volume or SPL usually a minimum 9 - 12 db change is needed. That would be dependent at what SPL you have started with.

It is confusing, but is worth checking my explanation.

There is a point to make in changing speaker placement, some of the sound may be absorbed by furnishings near them, standing waves, proximity to your ears.

Keep in mind that if your speakers are not the same impedance (or close) you will not attain proper volume. A speakers varies impedance at different frequencies. If the impedance comes to zero, you will be feeding a straight current and will fry the speaker.

dodger

[DrWho]

----------------

On 12/6/2004 4:11:57 PM dodger wrote:

In logarithym as applied to audio physics, a 3 db increase is what the average person will notice as a volume change. So to get a noticed volume change one has to double the power:

in watts: 1,2,4,8,16,32,64,128,256, etc., it is not a doubling of volume or sound pressure level, SPL.

Some with excellent hearing may perceive an increase in sound at 2 decibels. The average is 3 db.

Thus a 128 watt amplifier is not twice as loud than a 64 watt, it will have more headroom but only a a small perception louder.

By adding more power without doubling the amplifier wattage, you gain headroom before clipping.

To double the volume or SPL usually a minimum 9 - 12 db change is needed. That would be dependent at what SPL you have started with.

It is confusing, but is worth checking my explanation.

There is a point to make in changing speaker placement, some of the sound may be absorbed by furnishings near them, standing waves, proximity to your ears.

Keep in mind that if your speakers are not the same impedance (or close) you will not attain proper volume. A speakers varies impedance at different frequencies. If the impedance comes to zero, you will be feeding a straight current and will fry the speaker.

dodger

----------------

According to my text book "Modern Recording Techniques" by David Miles Huber and Robert E. Runstein, the dB system was designed such that a 1dB change was the smallest change the average "hearing youth" could detect within a frequency range of 1000-4000 Hz (aka, the midrange where we are most sensitive to change).

A 3dB change in SPL equals a doubling of power. However, the percieved change in "loudness" (not SPL) doesn't seem to be "twice as loud." The reason for this is very frequency dependent, but generally it's accepted that a doubling of loudness requires a difference between 6dB and 10dB. Note that a change of 10dB requires 10 times the power and 20dB requires 100 times the power! Power is measured in watts...so the difference between a 100 watt amplifier and a 200 watt amplifier is only 3dB. You'll need at least 400 watts though to percieve an actual doubling of volume from the 100 watt amp.

While reading my book, I came across a most interesting thing. Apparently our ears also produce harmonic distortion. A loud enough 1kHz sine wave is generally heard as a combination of 1kHz, 2kHz, and 3kHz. I think most of us here are already familiar with the Fletcher-Munson equal loudness contours, but for the sake of stating it, as a frequency moves away from 1kHz (about the middle of human hearing), it needs to be louder to be percieved as the same volume. The amount louder it needs to be goes down as the SPL at 1kHz increases. For example, a 20Hz tone needs to be almost 30dB louder than 1kHz to be heard as the same volume. In addition to these two things, the volume of a tone also affects the pitch. "For example, if the intensity of a 100 Hz tone is increased from 40 to 100 dB SPL, the ear will hear a pitch decrease of about 10 percent. At 500 Hz, the pitch will change about 2 percent for the same increase in SPL." (page 46). Our ears also create "combination tones when differ by more than 50 Hz." The two tones created are the sum and difference of the two tones (2000 and 2500 Hz create 500 and 4500 Hz tones).

Anyways, all of this is more or less interesting trivia. Just becaues our ears create harmonic distortion doesn't mean it's an irrelevant variable in speaker or amp design. I just find it interesting how much crap our ears add to the sounds we hear.

[3dzapper]

C.S.

Do you have the RF-5's set to large or small in the Yami? For 2 channel, set them to large with the LFE to both sub and fronts. That will get you more SLAM.

Rick