WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
Building, troubleshooting and testing of these amplifiers should only be
performed by someone who is thoroughly familiar with
the safety precautions around high voltages.
From looking at the spec. sheet of the amp. it looks like you should be OK. Not knowing just what speakers you have make it a guess however. 86dB for 1w @1 m is kind of low so it may not play real loud without clipping the amp a little bit. But that's one of the good things about a tube amp. "soft clipping"
Don't toss out your old amp, your 86db speaks could end up as your back channels for HT. Give it a try and if it doesn't work for you then your are in the right place to get info for building some higher efficiency speakers. If this is your first tube amp you are also in for some great fun, as there is a great sport called tube rolling! Something that you can't do with SS is easily change out your transisters, but you can with tubes and yes there are usually small differences but sooner or later you find what works best with your system. Then you will know why we like this so much.
You will find most small bookshelf speakers have a sensitivity of 86db per watt at 1 meter. With a 30 watt amp you should be able to play reasonably loud. To get this system to play even louder you should cross over the speakers at about 100 Hz ( varies with the type of system ) and feed the frequencies below (100Hz) to a powered sub-woofer. My Rogers GS-1 with a 5 inch bass driver and 86db sensitivity goes very loud with a 40 watt amp. Bass is rolled off at 90 Hz.The audible difference between a 30 watt and 40 watt amp is hardly noticeable.