...it's quite unusual that just only one speaker produces hum.
Try to switch all of the sources off or switch between each other and hear if there will be the noise
If the noise is being produced from any of the source you can contact your dealer and explain the situation
Less likely it will be a "tube break-in" in your tuner nor break-in of your SCD-1
The hum could be 60Hz from the power line and it's audiable from base-midrange driver. The tweeter can produce a 60hz claps that sound like a motorcycle if you will put your ear firmly to the tweeter. In this situation only both speakers can be affected. So if you place an ear firmly to the other speaker's tweeter -- you'll know for sure.
Sometimes the digital source components have very high output signal that can overload the input of the preamp (escpcially tube) and cause an offset violation of the input circuit of it. In this case you should try to use tape input instead of dedicated CD.
Try to switch all of the sources off or switch between each other and hear if there will be the noise
If the noise is being produced from any of the source you can contact your dealer and explain the situation
Less likely it will be a "tube break-in" in your tuner nor break-in of your SCD-1
The hum could be 60Hz from the power line and it's audiable from base-midrange driver. The tweeter can produce a 60hz claps that sound like a motorcycle if you will put your ear firmly to the tweeter. In this situation only both speakers can be affected. So if you place an ear firmly to the other speaker's tweeter -- you'll know for sure.
Sometimes the digital source components have very high output signal that can overload the input of the preamp (escpcially tube) and cause an offset violation of the input circuit of it. In this case you should try to use tape input instead of dedicated CD.