Pass labs X250.5 cracking noise
If it were an XA- model then yes having far more class-A bias on them you would expect a certain amount of expansion and contraction with warm up and cool down noises. But your’s is an X which is lower in bias than the XA, and should be getting that warm, unless you are driving it hard into difficult to drive low impedance/high -phase angle speakers. What are your speakers and do you push the amp loud? Also are the heatsink/s hot to touch after a couple of hours? Be good if you could measure the surface temp in the middle of the heatsink on both sides as they should be equal. Cheers George |
George, I dont drive them hard - I dont think i ever exceed low 80db spl. I also notice that the bias meter doesnt ever leave class A for my listening level. I drive a pair of wilson sophia 3s. I dont think the sophias swing wildly in impedance either (per wilson). I've gota be honest - dont know what a high phase angle speaker is! I'll give the temperature measurements a shot - thanks for the suggestion! Ragav |
Between 60hz and 180hz the Sophia 3’s are a hard load 3ohm with up to 50 degrees of negative phase angle (the dotted line is the -phase angel), it could make the 3ohms look like 1.5ohms to the amp. . https://www.stereophile.com/images/211Wilfig01.jpg Measure both heat sinks after a couple of hours playing normal level bass’y music. The heatsinks should never go over 60C. and that’s on the XA., the X I would expect to be less. Cheers George |
