Burn in after repair?


I had an amplification unit repaired with output and driver transistors replaced in one channel.  In starting to listen to the unit after repair, I find the sound somewhat thin and bass shy.  How normal is this?  Thanks for your thoughts/experience. 

 

jusam
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     If it doesn’t start sounding better, after a reasonable time powered up/in service: have the builder/Tech check the Bias.

I trust and have had quite a friendly, supportive relationship with this and other manufactures, and have personal thoughts and feelings about others.  I have also 

owned 5 of their products over the years and respect their additions to our wonderful hobby/interest/passion.  We all, likely, have our values and norms 

we have established over our life's experience.