How powerful is a Wavac MD-300B

Pani, a potentially very important point that nobody seems to have noticed yet is that the frequency response spec on the MD-300B has a lower limit of 40 Hz!!!

Assuming that spec is not in error, that would make the MD-300B a non-starter as a candidate, in my book. Besides that being an indication that the bottom octave will be severely rolled off, it is most likely also an indication that there will be adverse sonic effects at somewhat higher bass frequencies, due to phase shift issues.

In contrast, the EC-300B is spec'd to 20 Hz, and also has twice the bandwidth of the MD-300B at its upper limit (100 kHz vs. 50 kHz).

Also, I note that the EC-300B weighs nearly 60% more than the MD-300B, and appears to use completely different tube types in the input and driver stages.

All of which would seem to indicate that the sonics of the two amplifiers are likely to be considerably different.

Regards,
-- Al

Sensitivity of a given speaker is inly one information, even more important is, what kind of X-over is inside? Some can be a black hole for tube amps, even when speaker sensitivity gives the impression, that low powered amps can be used (Wilson is among such examples). Some tube amps are quite robust and have the ability to drive a wider range of speakers than others (Lamm ML2.1 is such an example but between ok and great there is also a difference) but I never heard a 300B amp in its full glory below 98dB speakers...

Good points Al,two 300b SET amps from the same manufacturer with significant differences in price,weight(likely bigger and better transformers) and front end tubes in the circuit.It`d be no way to extrapolate the sound of one amplifier based on hearing the other. Pani you could still really like the WAVAC MD 300b version but you need to hear it on your speakers.
Regards,

You may like the MD but you do like the EC. Depending on the speaker (and your ears), the differences could be small or huge.

From reading your posts, I think the EC is the one for you. Yes, it's more expensive but there is an old saying: "Sometimes the cheap comes out expensive".

I have and love 300b amps. They all had that glorious midrange but the better ones have extension in both directions.

My only worry is whether the MD can drive the Tannoys. I dont want the deepest bass at this point, but mid bass required to enjoy stuffs like Dire Straits, Guns n Roses etc should be there and adequate.