Newbie looking for amp. suggestions

[Tyler]

Hello all, first post here. I am looking to get a set of RF-7s in the near future and have a question regarding my receiver. I have a Yamaha HTR-5250 5.1 receiver that supplies 110w x 5. I understand the RF-7s are pretty efficient but an e-mail from Klipsch suggested 200watts per channel for optimum performance. I am not too concerned with getting the most out of these at their maximum output, but more concerned with sound quality at moderate volume levels. I will be using them primarily for 2 channel audio. Would I benefit from a pre-amp or entirely different receiver in general? My receiver does have pre-amp outputs. I am not familiar with any of the pre-amp solutions or brands so please be specific if you care to make a suggestion for me. Thanks in advance.

I will be using the other channels occasionally for SACD listening and of course DVD playback. I will be mating the RF-7s with an SVS subwoofer.

[Cal Blacksmith]

A little more info is needed to answer your questions.

What kind of music will you be listening to?

How loud will it be?

What is the size of the room?

Carpets?

Furniture?

What have you had in the past for equipment?

Have you considered separate components? (A receiver is a combined unit of at least a pre-amp, amp and tuner)

How much money do you intend to spend?

Solid State or Tube?

Are you happy with the sound you have now, looking for a DIFFERENT sound?

Have you heard a good tube pre and amp?

You will get the highest quality from separate components.

Are you ready to start the journey down the "upgrade road?" You might well spend a pot load of money in your search to better sound. Most of us have!.... AGAIN AND AGAIN[][]

[leok]

I listen to classical chamber music on RF-7s. My amps are 3.5W SET

using the 2A3 output tube. The levels I listen at might be considered

"moderate." For more power I use an 8W no-feedback pp amp or a Tripath

design. For even more power I use the 25W Crown D-45.

All of these amps produce very low distortion at low (below a Watt)

power. If you want the RF-7, or any efficient speaker to sound natural

at moderate volume, the amp has to produce low distortion at low power.

Tube amps should use their 4 Ohm outputs.

Many tube amps are good. SS class-A amps tend to be good. A few more exotic ss designs, like the Crown D-45, are also excellent.

Get a good power line filter. Belkin F5C980-TEL, avail. at Staples, is good.

Good luck,

Leo

[Audio Flynn]

I have heard RF-7 sound good with a "home designed" 300B tube amp.

Style of music room budget interesting tubes and the other details are very pertinant in making a recommendation.

200 watt per channel sounds unnecessary, odd, and incorrect.

[leok]

I recently heard the group "Tortois" in concert. The hall was small and

sound HUGE. I suspect, with 200W, one could re-create, with RF-7s, the

sound and impact I experienced in that small Somerville, MA venue. I

used earplugs in that concert. At home, I listen to the Tortois CDs,

without earplugs, on the various amps and speakrs listed below.

Leo

[MrMcGoo]

200 watt per channel sounds unnecessary, odd, and incorrect.

I agree with Klipsch tech support on the 200 watts in a solid state amp for best results. The RF-7s dip down to 2.8 ohms. The phase angle is greater than 60 degrees at 74 Hz. A difficult phase angle heats up output transistors and requires more power output due to the wasted power going to heat up your output transistors.

http://www.sound.westhost.com/patd.htm

Low wattage solid state amps have one or two pairs of output devices per channel. A 200 wpc solid state amp may have five or more pairs of output transistors per channel. It is easier to stay in the safe area of operation with a high power solid state amp with more output devices.

There is also a preconcieved idea that higher powered amps have more noise and distortion. On many amps this isn't true. Most amp manufacturers realize that the first watt is critical. Some are better than others on the first watt, but that is true in tube amps as well.

Tube amps need less power due to 4 ohm taps being available. Also, tube amps clipp softly; solid state amps may blow a tweeter when they clip.

Bill

[michael hurd]

I have to agree with Mr.Mcgoo, 200 watts per channel affords one some headroom and most amplifiers in this power range have sufficient output devices. If we say that for "normal" listening the amplifier is putting out 20 watts per channel, there is 10 db headroom available for transients.

For those thinking that 20 watts is a lot of power, you have to first know the distance from the speaker to the listening position.

Using an internet calculator, the spl at the listening postion can be calculated here:

http://www.myhometheater.homestead.com/splcalculator.html

Using 12 feet as an example, and placement #2 ( 2-4 feet from walls ), 20 watts gives us 109.8 db at the listening position.

15 feet of distance would drop the sound pressure level to 107.8 db at 20 watts.

[pauln]

The figures for SPL are probably true physical peak levels rather than SLP meter reading levels, right? You should not expect that an SPL meter will show true physical peaks... when the SPL meter is set on "Peak" it reads 13dB lower than the true physical peak (per PWK).

This is because the weighted motion time base of the meter indicator was normalized to work best on human "anouncer" voice, not music. Music is more dynamic and packs more punch before the voice based meter speed can respond.

Just trying to help,

Paul

Oh, and Tyler, welcome to the forum.

[tillmbil]

I all too often hear that with SS and efficient Klipsch speakers you do not need a lot of power. I say for rock-n- Roll those people need to try both. Every Klipsch speaker I have added more SS watts to have sounded better in the 90db range and up.

They usually sound better in the lower levels too. Tubes are a different beast, and can sound great at both high and low volumes without a lot of watts depending on the quality of the amp. As for SS strictly class A amps. I have not heard one yet. My M80 does stay in Class A by pushing a button up to 20 watts. Never really noticed a difference becasue it is for HT, but it sure does run hotter.

[BiggerIsBetter]

I'm not sure that I agree that you need more watts, but i do think you need BETTER watts. Unless you want to go with separates (which you should) the next best first step would be to use your pre-outs and get a decent amp.

[Jay L]

acurus

aragon

adcom

crown

hafler

mcintosh

all of these have worked good for me, really an amp shouldn't sound at all.