Do I need an amp?

[randy98ss]

I am currently a 7.2 system with a rx-v3800 through Klipsch Reference RF-5. The reciever has 140 watts per channel and I believe the RF-5's are the next to the biggest Klipsch made at the time. I am using that series speaker for all my speakers.

Would using the Emotiva XPA-3 or 5 make a huge difference in the sound? From what I have read the advertised 140 watts per channel that my yammie as making is not really what is being output, sorta like a car with horsepower. After the power reaches the rear wheels, its no longer the advertised horsepower.

I have never used a seperate amp before, and not sure what I am missing. I see alot of people opt for a smaller reciever like the rx-v663 and use the extra money for an amp. Is it need in my system?

 

[rnatalli]

I don't think you need an external amp for your setup. Your 3800 should do just fine. I doubt you'd notice any difference in SQ given a controlled environment. But if you have money to burn, go for it!

 

[Midcow2]

Separate amp not needed!

I am currently a 7.2 system with a rx-v3800 through Klipsch Reference RF-5. The reciever has 140 watts per channel and I believe the RF-5's are the next to the biggest Klipsch made at the time. I am using that series speaker for all my speakers.

Would using the Emotiva XPA-3 or 5 make a huge difference in the sound? From what I have read the advertised 140 watts per channel that my yammie as making is not really what is being output, sorta like a car with horsepower. After the power reaches the rear wheels, its no longer the advertised horsepower.

I have never used a seperate amp before, and not sure what I am missing. I see alot of people opt for a smaller reciever like the rx-v663 and use the extra money for an amp. Is it need in my system?

Your speakers 8 ohms and are very efficient 99dB (meaning they will play loud without much power) and have your speakers have a maximum watt rating of 150. NO, you do not need a separate amplfier.

You would notice very little difference in sound using a separate amplifier such a a Emotiva or a Behringer.

 

[jamie2112]

No you wont notice a difference. As Midcow stated your speakers are very efficient so your 140 watt a channel AVR is fine. Your speakers are rated for 150 watts so you For SURE don't need an amp. I would keep your receiver...

 

[GlocksRock]

I too will echo what the others have said, and that is with speakers that efficient, and an amp that strong in your receiver, you wouldn't get any benefit from getting an amp.

 

[Ron Temple]

Do you need an amp, no. A friend of mine just added an XPA 5 to his Marantz 8xxx running Heresys and LaScalas. He hasn't stopped PMing me about how much of an improvement, how much more powerful, more dynamic, yada, yada, it sounds. It's all about what makes you tick. There are those that can/can't or will/won't hear a difference. IMO headroom always is positive, objectively and subjectively.

 

[jostenmeat]

Ampity ampity stampity wampity

well. I guess there are other things besides sensitivity. Minimal impedance (Klipsch often goes down to 3 ohms like so many speakers), and current/phase angle stuff.

Then there's the SPL desired and the seated distance, but yeah those speakers have high sensitivity.

Who knows. You can put an end to the speculation, and try emotiva or outlaw, and return it if there is either zero improvement, or just so small that its still not worth the money. You will lose out only on shipping charges. Or, if you are lucky you can find a local dealer willing to let you try something for a day or two.

I've seen people return the amp and keep the amp, even just in the last month.

FWIW.

 

[gus6464]

There are some Klipsch speakers that benefit from an amp. The RF-x3 series speakers dip to below 3 ohms and can strain a receiver if played at high SPL for long periods of time. By long periods of time I mean watching a two hour movie. Just because a speaker has a sensitivity of over 90dB doesn´t mean they will never need an amp.

 

[jostenmeat]

Just because a speaker has a sensitivity of over 90dB doesn´t mean they will never need an amp.

Precisely.

My stereo speakers have a sensitivity of 92 db.

OTOH, the minimal impedance is 0.7 ohm.

 

[Seth=L]

The Yamaha RX-V3800 is more than capable of handling Klipsch reference series speakers momentary 3 impedance dips. And to reiterate what others have said, they are very efficient and they will spend most of their time out of 3 ohms if you don't run them full range, and even then I wouldn't worry.

If you have a subwoofer make sure you are using the receiver's bass management to keep the lowest of lows out of your speakers. If you don't have a subwoofer you should be fine running them full range, but a subwoofer always helps fill in that low end. Getting a bigger more powerful amplifier won't improve your bass, at least not as notably as a good subwoofer can.

 

[Seth=L]

Precisely.

My stereo speakers have a sensitivity of 92 db.

OTOH, the minimal impedance is 0.7 ohm.

It's possible many speakers do this, you may never aware. Just avoid those 20hz test tones, and Resident Evil: Apocolypse if you can.

 

[jostenmeat]

Seth, do you know at which frequncy(ies) the minimal impedance is reached with the OP's speakers? I don't even know what the minimal is.

From what I have gathered, a sub does not always help so much with minimal impedances in today's speakers, because it often resides in the mid-bass.

Which would mean that even with a solo guitar, its basically "always being hit". Meh. I think some important factors are still missing, especially the most important one IMO: the SPL levels the OP wants to hit?

IOW, if it was just modest volumes, I'd think anything will work.

I will make sure to avoid 20khz test tones and Resident Evil, lol.

 

[wire]

Do you need an amp, no. A friend of mine just added an XPA 5 to his Marantz 8xxx running Heresys and LaScalas. He hasn't stopped PMing me about how much of an improvement, how much more powerful, more dynamic, yada, yada, it sounds. It's all about what makes you tick. There are those that can/can't or will/won't hear a difference. IMO headroom always is positive, objectively and subjectively.

I agree
Just let someone try it out and see if he or she likes it . To much turmoil in this forum over next to nothing .

 

[Seth=L]

Seth, do you know at which frequncy(ies) the minimal impedance is reached with the OP's speakers? I don't even know what the minimal is.

From what I have gathered, a sub does not always help so much with minimal impedances in today's speakers, because it often resides in the mid-bass.

Which would mean that even with a solo guitar, its basically "always being hit". Meh. I think some important factors are still missing, especially the most important one IMO: the SPL levels the OP wants to hit?

IOW, if it was just modest volumes, I'd think anything will work.

I will make sure to avoid 20khz test tones and Resident Evil, lol.

Nothing wrong with 20khz.

My limited understanding, very limited, of speakers is that lower frequencies typically impose a more difficult load as well as higher power demands.

Resident Evil: Apocalypse killed my M&K MX-100 subwooferand shut down the Carver AV-505 amplifier I had at the time. The load took a devastating toll on the output section on the M&K. The amplifier saw fit to go into protect mode while driving the inefficient 6 ohm nominal PSb Centuri 600i floorstanding speakers I had at the time.

 

[PENG]

Precisely.

My stereo speakers have a sensitivity of 92 db.

OTOH, the minimal impedance is 0.7 ohm.

0.7 ohm? I hope it is a typo, or your amp is as big/heavy as a welding machine.

 

[PENG]

Ampity ampity stampity wampity

well. I guess there are other things besides sensitivity. Minimal impedance (Klipsch often goes down to 3 ohms like so many speakers), and current/phase angle stuff.

Then there's the SPL desired and the seated distance, but yeah those speakers have high sensitivity.

I would have agreed with you in other situations but not in this case. The specs of the OP's RF-5 can be found here:

http://www.klipsch.com/products/details/rf-5.aspx#specifications

99 dB 2.83V/1m
Nominal impedance=8 ohms

My 87 dB 8 ohms nominal 4 ohms minimum speakers would need 16 times more power to produce the same SPL (in an anechoic chamber). Yet my old 3805 used to drive those speakers with no issues at all. Granted, as you said we are missing some vital information such as the impedance vs frequency and phase angle vs freq curves, but who cares, when you are talking about 99 dB sensitivity. Even an unusually large phase angle of 60 degree would only offset 3 dB (Cos60=0.5) of sensivity.

Incidentally, last week I have had a chance to listen to a pair of KEF 105.3 rated 4 ohms. We drove them first with a Yamaha RX-V2400, then added a Bryston 4B. The RX-V2400 on its own had no trouble driving those 4 ohm speakers to very high SPL in the approx. 16X28X8 room.

Don't get me wrong I do think separate amps (or a big welding machine for your 0.7 ohm speakers) are the way to go for low impedance loads but I just would not worry about the RF-5 based on its published specs. Of course the specified 8 ohm impedance is nominal not minimum, but as Seth=L pointed out, any low dips would not be long lasting. If the dips happen in a wide enough spectrum including the mid bass area, a reputable company such as Klipsch would not have rated it 8 ohms nominal. Driving such highly sensitive speakers with a receiver is like driving speakers of more typical sensivities (say 89 to 91 dB) with separate high power amps.

 

[wire]

0.7 ohm? I hope it is a typo, or your amp is as big/heavy as a welding machine.

My Bryston is very close .

 

[randy98ss]

Thanks for all the advice guys! It seems the general consenses is that I do not need an amp with my current setup. It saves me some money that I could use for bills, lol.

 

[ParadigmDawg]

****NOTE TO SELF****

Go get -Resident Evil: Apocalypse and see how loud you can blast it......

 

[mtrycrafts]

I agree
... To much turmoil in this forum over next to nothing .

If that is the case, adding an external amp is next to nothing, why do it?