Toccata Grande, Part 2

By Lars Mytting
20 Jan 1998

And now... on stage!

I find the Toccata a quite exciting performer. The soundstage is big and quite precisely defined, maybe with a sense of "artificial" focus. The goal of good transient response was fulfilled -- there is always a great sense of attack and agility, while the sound remains well controlled and undistorted. Voices do not have the homogeneity of a simple two-way, but the clarity is better than expected. The speaker is best at home with rock and jazz, but it has surprised me with quite honest reproduction of classical music. It is not the most detailed of speakers, but brings the drama and nerve of music alive.

There are some irregularities in the soundstage when listening off axis. Some of this (especially the dip centred at 200 Hz) can be allocated to floor reflections and wavelength-related cancellations due to the many drivers, and some of to the MTM configurations.

Probably the biggest disappointment is the response in the lowest octave. Bass is quite tight, loud and "fast", but I had hoped to get more output to 35 Hz. When playing very loud, the bass may sound more or less choked, maybe due to the narrow t-line. If you are mad enough to build a Toccata, I suggest you make the t-line wider, with a ratio for two drivers of maybe 1.5. I have also tried other 10" drivers with higher Qts, but with no significant change in the lower octaves.

The bass response is not fully investigated, because I have had few well suited amplifiers connected. I have mostly used a Hiraga Le Monstre of 8 watt, but this amp meets its limits quite early due to the difficult impedance of the Toccata. A sturdy class A design of 20-30 watt would probably be optimum Fig. 13. Son of Zen. Tests showed that even a small, 20 year old Sony amplifier could provide dramatic SPL!

Afterwards: Older and wiser (maybe)
The biggest technical achievement was probably the method of sand-damping with a thin outer wall. This is definitely a method I will recommend. Supporting the magnets also proved a must. The effect of the soft baffle is not documented, but the technique can only be an improvement.

Impedance turned out lower than expected, with some difficult areas. The major flaw is probably the low end bass response. Some listeners may be disappointed due to the promises such a large cabinet gives. A bass reflex system with lower sensitivity is maybe what most will prefer.

But all in all, I am satisfied with the project. The Toccata may not have the detail and neutrality of a smaller two-way with top components. It likes to show off; behaving as a Anna Nicole Smith-like, full-breasted blonde, needing little to get turned on, and always great fun, but maybe overall too much for some tastes -- especially compared to the grace and refinement of a slender, Nobel-prize intelligent woman like, say Arundhati Roy, author of God of Small Things. Both are catches of the century, but you can't get it all, and in emotional fields like music it would perhaps be hard to trade the intellectual depths of Arundhati for the mad fun of Anna Nicole.

Lars Mytting

About the
author

Print this
article

Email this
article