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Little confused here. I hear people say you needs lots of power to drive Magnepan LRS speakers properly. Ok, to I upgraded my amp to an Musical Fidelity A3 dual mono integrated amp. Supposedly it does 180 watts into 4 ohms and that amp is high current design. Well with cd, I can get it pretty darn loud with no audible distortion. But to get the same volume, with vinyl I have to go up louder with the volume knob. I notice that sometimes once volume know goes up past lets say 1:00 o clock, sometimes I will hear distortion / breakup. What gives. What is happening, are the speakers reaching their "limits". Small surface area? Normal? Crazy thing is that the volume knob goes all the way to 6:00 o clock in terms of loudness. I would imagine that if I even attempted to increase to volume to that level, speakers would blow up. Ger.
Edits: 08/10/22Follow Ups:
First, overall phono gain is typically less than the 2V standard CD output, so it is completely normal to have to advance the volume knob further on phono to achieve the same loudness as the CD. This is independent of the speakers used, so changing speakers will not change this.
Second, since the distortion is on vinyl replay and not CD, it is safe to say that it is a problem that is isolated to your turntable. There are a lot of possibilities here. Worn cartridge, incorrect cartridge alignment. Binding tonearm bearings, acoustic feedback.
I would suggest that you check your alignment thoroughly, also there is a very simple test for acoustic feedback. With the turntable off, as in not spinning, lower the stylus onto the surface of the record. Advance the volume control to where it is when you hear distortion while actually playing records and gently tap the plinth. Do not let go of the volume control. If you have acoustic feedback you will hear a low roar that will begin increasing in loudness,, even though you are no longer advancing the volume control. If this starts to happen, quickly turn the volume down so as not to cause any damage. You will have at least identified part of the problem. Good luck.
It doesn't take all that much power to drive the transducers into contact with the magnets at low frequencies. I suspect that's what you're experiencing.
I suggest to limit low frequencies and/or turn it down.
Dave.
Exactly right!
Yes,
All single ended (not push-pull ie 20x) Maggies have unsymetrical magnetic field . As you go down in frequency the displacement goes up with the Square of the signal. That is going from 100Hz to %0 Hz at the same dB level requires 4 times the displacement!
Best way to help these Maggie's is use a high pass and supplement with subwoofers.
Just because the volume knob goes to 6 o'clock doesn't mean everything is going to sound good all the way there. The amp is not just amplifiering the good stuff, it's also amplifiering the distortions, and vinyl has a lot more than CDs.
Check the output of the amplifier when playing vinyl with an oscilloscope and look for low frequency / subsonic garbage from record warp / feedback or rumble. You can buy a suitable 'scope from Amazon (for example) for less than $30. https://www.amazon.com/Oscilloscope-Handheld-Portable-Ultra-Small-Bandwidth/dp/B07Z57BGBZ
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Science doesn't care what you believe.
This is exactly what I was thinking. Subsonic noise. If you can substitute in a pair of normal speakers, check to see if the cones are moving excessively. If yes then it is subsonic.
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