Powerline Four power amp
I was lucky enough to inherit a Powerline Four amp along with the SL2 preamp. The amp went into protection mode several years ago and has sat unused . When that amp went out I purchased a Peachtree Audio amp. The Crown amp was recapped recently but the amp sounds so dull and lifeless. Is it t possible the recapping has caused the amp to sound dull and lifeless or is it that the Peachtree Audio technology is so much better that the Crown just cannot compete? I am using the same turntable preamp and speakers with both amps and the difference in sound quality is incredible. The Peachtree amp does have 55 watts per channel more than the Crown so that could be an issue but when I have them both at the same listening level the Crown sounds like a blanket has been thrown over the speakers.
How 'recapped' has the amp had? This blanketing issue seems like filter caps are not handling transients correctly.
Have you also refurbished output devices: cleaning and replacing the thermal compound.
Also, check input bypass capacitors: they may have changed values and act like a low-pass filter.
May be low power supply issue: regulation is lacking? Check the filtering caps.