I ordered Marshall DSL1HR valve guitar amplifier head.

As you can see in specs it has built-in "Emulated line output". I know that a valve amplifier must be running with a speaker cabinet attached.

Is there any problem if I run my valve guitar amplifier without speaker cabinet attached, but with headphones plugged in the upper mentioned "Emulated line output"?


You're right about the danger of running the tube amps without a load.

During "Silent Practicing" you can disconnect the load. Don't worry, your amp has a built-in dummy load. And when you plug a speaker cable in the output jack the amp output switches to the actual load (speaker) from dummy load.

But never leave the speaker cable having one end plugged in the output jack and the other end unconnected to cabinet.

  • \$\begingroup\$ But why this guy has different opinion: youtube.com/watch?v=FY3C2hWKE9U \$\endgroup\$ Mar 6 '19 at 13:56
  • 2
    \$\begingroup\$ The guy in the video talks about the danger of running the valve amps un-loaded. He doesn't say anything extra. As I stated in my answer, your amp has a built-in dummy load to prevent the amp running without a real speaker attached. The mechanism inside the output jack automatically switches to the real load when you insert a speaker cable. As a conclusion, during silent practicing (i.e. headphones plugged in) you can safely run the amplifier without a speaker attached. \$\endgroup\$ Mar 6 '19 at 14:21

Not the answer you're looking for? Browse other questions tagged or ask your own question.