Ever so often Audio-Technica like to update their line of products. This time, it is the lower end of the Solid BASS series with the ATH-CKS50 and ATH-CKS70. The new models will be known as ATH-CKS55 and ATH-CKS77. Beside the very obvious name 'improvement', I am not quite sure what has been changed. As usual, Audio-Technica will like the buyer to find out for themselves. Hmm...