Luxman..It doesn’t go to 11??
 

Most likely this question stems from my lack of engineering and electrical education.
I own a Luxman 507u rated at 200 watts into my 4ohm SF Cremona M speakers.
Lets say the lowest setting on my volume knob is equal to 1 (far left), the arrow pointing straight up is 6 (50%) and full volume is 10 (far right).
The Luxman delivers full, rich and crystal clear sound up to number 4. After that, the mid range begins to distort and the sounds becomes intolerable.
The decibel level at #4 is quite loud but with certain types of rock music, I would like to have a bit more “oomph”
I am baffled as to why a new $7000 integrated amplifier would not be able to deliver stable power to at least the 50% mark of my total volume range.
I also notice that as I increase the volume during a song, a “crackling” sound is heard.
Am I missing something:scratch2:

Sounds like a bad unit, or some kind of clipping.

I agree with Masterlu: you're clipping the amplifier. I wouldn't push it, or you might damage your speakers.

How far one can turn the volume knob depends on many different variables (the load presented by the speakers, the sensitivity of the speakers, the source's output characteristics, the music being played, etc.).

I bet you can turn it up higher than 6 on classical albums that are recorded to be dynamic; not compressed with levels almost always maxed-out like a lot of rock music.

I doubt there is anything wrong with your amplifier, you simply need more power for your system: moderately powered integrated amplifiers might not be for you.

Time for separates for you, I'm afraid.

have you got the SF's hooked up to the 4 ohm taps on the Lux?

bodiezaffa.......Your volume knob is not a zero to 100% output level control, and 12 o'clock is rarely 50% of output. In fact it is usually well past 50% output, especially the peaks. Your maximum clean volume is not necessarily based on the volume position as much as it is based on the dynamic range of your source material.

You must remember that every 3 decibel increase in output (volume level) requires a doubling of output power. If you are listening to music with an average volume level of 15 watts, your peaks are likely 10 to 12 decibels higher. Doing the math, that equates to 150 to 240 watts of output power required to faithfully reproduce the music without clipping the peaks. Lets assume this is happening at the the 11 o'clock position on your volume knob with a given piece of music. You are essentially using every single watt your integrated amplifier is capable of delivering within its distortion rating. Turning the volume knob to 12 o'clock will push the amplifier into clipping on the peaks because you are now trying to get 300+ watts on peaks from an amplifier only capable of delivering 200 watts.

Another thing to keep in mind is the amplifier's power supply and its ability to deliver a continuous voltage supply to the output stages at maximum rated output. Many amplifier designs can achieve maximum rated output, yet the power supplies are not sufficiently stout enough to maintain the amplifier's maximum output for any length of time. This is often the case with many integrated amplifier designs, as space and weight considerations during the design take precedence over what might otherwise be necessary for a premium grade power supply section. I am not saying this is the case with your Luxman 507u, but it could be part of the equation that is adding to your integrated amp's dilemma. You may be expecting more performance than the Luxman integrated is capable of delivering, even into the 91 dB efficient Sonus faber Cremona M's.

No way!! Dont tell me there are 4ohm taps!! Are you sure? I see you have a Lux as well but I dont remember reading about 8ohm and 4ohm taps:eek2:

I think you might be right J.

Yes my amp has 4 and 8 ohm taps - not sure about your 507u. Lovely speakers by the way.

The tube lux has separate taps. The ss doesn't. Whew.

bodiezaffa.......It might be time to consider a McIntosh MA7000. :)


http://www.sonicflare.com/McIntosh%2...mb-600x400.jpg