from the owners manual....
IMPORTANT NOTE: Do NOT use your VT-300B without a speaker
load. Doing so will cause damage. Running this amp without a speaker
load is a VERY BAD THING. Don’t do it. Ever. Remember, this is a
vacuum tube amplifier, not a solid state amplifier.
REPEAT IMPORTANT NOTE: Do NOT use your VT-300B without a
speaker load. Doing so will cause damage. Running this amp without a
speaker load is a VERY BAD THING. Don’t do it. Ever.
Using the WTB-300 Without Speakers -This amplifier is NOT designed to
be used safely without the loud speaker plugged in. Doing so will cause
serious damage to your amplifier. We keep saying this because it is so
important.
here is the link
http://www.eden-electronics.com/info...011/WTB300.pdf