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F205: Den lille høyttaleren som setter ny standard for lyd


Ongoing work on a new version F205H with improved radiation pattern control is very promising. While the speaker will indeed look quite strange, the benefits far outweigh any visual appearance concerns, for the serious audiophile.

Significantly improved Slam!, improved tonality, improved realism and better 3D rendering. And now most of this experience is less depending on room acoustic properties.

Improvements are achieved by changing the baffle, so speaker presents a wavefront similar to a large horn. It is the shape of the baffle, combined with the acoustic port radiation control that makes this possible.

F205H - continued:

Analysis confirms significantly improved early reflection attenuation, necessary changes to eq has been designed, shape and size of the baffle modifications have been tested. Next step now is a working prototype, which will be tested and analyzed. Part of this testing will be listening tests comparing the new speaker - the "H" - to the original.

The voicing will be slightly changed towards a more full and warm sound, with just  a little more level in the 100Hz-300Hz range.

This modification will give the already quite spectacular F205 to even more realistic and addictive sound.

F205H - Upgrade kit for F205:

For those very few that may be interested in upgrading to the F205H, this will be possible:

  • Physical changes to the speaker consist of parts mounted on the side panels of the speaker
  • EQ changes can easily be implemented in dsp-powered systems, which includes all T6-A powered F205+T6-A systems

The parts may look simple, but they are quite complicated to make in limited numbers, so availability will be limited.

F205H - ongoing work:

Testing prototypes in the less fortunate Media Room. This is quite difficult. All aspects of the nice F205 sound must be preserved, while improving tonality, solidity of rendered objects, more realism, still sound good when seated far off-axis.

There will be further experiments with different shapes of the baffle modification, with continuous evaluation by listening and measurement analysis.

Visual appearance is also a concern, though not so important, because there is always the option to keep the original F205, which does not look strange.

Results so far have already given more knowledge about optimal radiation pattern for loudspeakers for small rooms (all domestic rooms..), and this knowledge can come of use in future speaker designs.

F205H - what may be achieved:

Using one possible version of the F205H in the media room now for several days, some impressions manifest.

Tonality and timbre of individual instruments is significantly improved in the mid-to-low-midrange, they appear even more separated and clear. There is greater contrast in the presentation overall, both tonally, timbre and spatial.

Holographic rendering is more coupled to the recording. Where the original F205 kind of smooth things over towards the extreme left-right sides, the new F205H is less forgiving and places hard-panned instruments a bit closer. This is a problem that needs to be solved.

Solidity of rendered objects are very good now, and dynamics and transients even better. Very engaging to listen to, at both very loud and very low listening volume.

Who is John Galt.

Using the new F205H in the media room, both for music, movies and general media content, I find I like it more as I listen to this. The clarity and separation of rendered objects is addictive. I have not done any further improvements to fix the issue mentioned above.

Now, further progress with this improved technology is something I will consider in the coming days - or weeks. There is a reason why I have not published any images. There will be changes in the business model of the company, and those changes will affect policies regarding publication of technological solutions.

This is not easy to get right, slowly making some progress.

The problem is that the speakers draw attention to themself, they do not disappear like the original F205 does. This prevents rendering of a truly realistic and believable scene, it sounds sort of artificial. I want the forgiveness of the original f205, combined with more solid and impactful sound. And it gets closer now.

Testing continues. Looks like the early version I rejected, will be close to the final, with some small modifications.

There is just something with this sound, so solid and real. It will not sound smooth like the original F205, it will be more precise, for better or worse, because the sound will be more depending on the qualities of the recording.

I had a question about whether this change on the speaker can be measured. Of course it can, and indeed, a lot of measurements and analysis has been performed, during development.

I can show how the radiation pattern changes, with reduced off-axis radiation starting quite early in the 400hz-1KHz range, and then there is a significant attenuation at lower frequencies 100-200Hz, for sound radiated backwards.

This is from an early prototype version, measured in-room, quite close to the speaker, valid only below around 2KHz:

F205H - results so far:

Living with the H for a while now, and testing comparing to original F205, and also to F105, I have come to the conclusion that this was not a good idea. The overall impact on sound is negative, due to some issues that seems to be difficult to overcome.

Tonality is not improved, rather it is compromised, and this is not possible to fix with eq. The original F205 sound softer, and this slight softening is also perceived as more pleasant and realistic, the H is too sharp and hard.

Rendering is compromised, it is too sharp and accurate, causing images to tend to appear at the L and R speakers, or dead center. Hard-panned objects moves forward, as for the original F205, those objects tend to appear behind the speaker, with a much more realistic image rendering. Overall soundstage rendering is better with the original F205.

The effect of the acoustic ports were tested, and it seems the radiation control is sufficient to provide this sense of realism to transients and dynamics: