Paul Klipsch was right - What the world needs is a good 5 watt amplifier


For those who are questioning whether a low power high quality amp would be able to properly drive any speakers I've recorded a short video demonstrating very high SPL level from a speakers with average sensitivity. The video is of very low audio and video quality as its recorded from my smartphone. However, the microphone used for measuring the sound pressure is MiniDSP UMIK-1 and the software used is REW (Room EQ Wizard). During the tests the amplifier didn't show any hint of stress of distortion

The speakers used in this video are Sonus Faber Olympica II and the integrated amplifier is Pass Labs INT-25. According to some third party reviews the Olympica's are thought load for the partnering amplifier as their sensitivity is averagely rated (88db) and the impedance curve drops down to 3 ohms in the bass region with a estimated EPDR (the point where the impedance curve is intersecting with the phase angle) of 1.6 ohms. The pass labs is rated at 25wpc @ 8omh and is said to be stable down to 1 ohm doubling its power at 4 and 2 ohms. According to the manual it can deliver 200wpc @ 1ohm before the protection circuit is activated. 

So, the point of the video is to show that the Pass with its poorly rated power (25wpc) can drive even demanding speakers to insanely loud levels without any sound degradation. 

  

 

celestial__sound

Showing 4 responses by phantom_av

Funny thing which i can't seem to explain is why this phenomenon occurs on the Atma-Sphere amplifiers and pre-amps. Iv not really experienced this on other audio gear iv tried tested personally or at friends.

If I Measure the room SPL Level at a friend's house 95db to 100db on peaks, It gets rather uncomfortable. This applies to SET and SS.

However on the Atma Sphere gear, 90db in-room spl measurements don't actually feel loud at all, even 95db don't really feel uncomfortable. If anything you kinda get the urge to keep cranking the volume up.

105db or higher for 5 watt to sound sufficently good enough at decent volume level and even then it depends on the room and seating distance. These amps struggle with bass.

 

Personally i would not touch flea watt amps unless my speaker is 110db or higher in sensitivity and room is optimised whilst at the same time im not sitting to far away.

i prob hit about 90db splt levels in my room which is heavily treated. I was talking about speaker sensitivity and small amps, you need very sensitive speakers if you using anything under a few watts.