I agree with Flex and Detlef. The required use of MIT cable with Spectral only applies to their power amplifiers. However, I believe it is essential that you use Spectral preamplifiers like my DMC-20 with Spectral amplifiers. I too have used other than MIT cables without any detrimental effects with older DMA-50 amps. I recently have been using Virtual Dynamics cables with my Spectral DMA-50 amps and discovered something quite interesting. Prior to using these cables, I had been using MIT 750-plus speaker and MIT 330 interconnect cables. When using these MIT cables, the amps always ran fairly hot. After inserting the Virtual Dynamics Cryoed Audition power, speaker, and interconnects cables, I was surprised to find that the amps now ran cool to slightly warm. Rick Schultz had told me that this would happen, but I honestly didn't believe him until I ran his cables for a couple of days and touched the amps. It is quite remarkable, really, and they sound far better in every respect than the MIT cables I had been using.