When favouring smaller single end tube amplifiers, running in class A, the need for high efficiency speakers become very acute. And maybe the best way to achieve high sound pressure from low power is to use horn speakers.
After been in touch with the Sonido people in Budapest I obtained the smallest of the fullrange drivers and built the proposed horn for the driver. I am happy that I picked the 5" driver as, comparing to the bigger 6,5" and 8", I may not get earthquakes, mid and highs sound very good, whereas the bigger horns may sound a bit murky. On the other hand I don't miss the low notes either.
There were no bigger propblems assembling the horn. Got the pieces of 19mm MDF precut from a lumberyard and had access to a workshop where I could glue the pieces together. A good friend of mine did the painjob, though I have managed to scratch the speakers as they have been to various DIY meetings and carrying them up and down our spiralstairs at home is not healthy for BIG speakers.
I must say that I am very happy with my speakers.