April 18, 2014

PSE-144 up and running

People have been asking for photos of PSE-144 set up in a room, sitting on its bass module. Here it is - sitting on top of a 60L bass box with an 18" Eminence Magnum woofer, with a bass trap behind. The box is 600mm (24" wide) and the horn itself is 900mm wide x 600mm high.

April 7, 2014

HE3 form factor

Which bass module would you prefer?

The speaker on top has a familiar form factor, with a dome tweeter and 6.5" midrange driver, but with a twist. It features 93 dB sensitivity, high enough to be driven by most valve amps. The bass module will feature a ported DSP powered 10" woofer, except version B which fits a larger 12" driver. 

A - a simple box where the front is angled to match the front baffle of the speaker on top

B - side walls angle out to fit a 12" woofer

C - both front and back angled out

D - a simple rectangular box

April 6, 2014

PSE-144 dispersion

PSE-144 almost maintains its horizontal pattern control down to 250 Hz, with modest midrange narrowing. At very high frequencies the pattern narrows. Around 5 - 7k one can see that there is a difference in the axial and off axis response from around 15 - 40 degrees. This is very useful data to consider in making choices about what to correct in the crossover and how this speaker should be set up in a room.

The horizontal design beamwidth is 80 degrees.

The directivity waterfall plot shows the same data in a different way. The data is shown with the minimum smoothing the software allows (1/12 octave) and here we can see the effectiveness of the dispersion control employed in this horn. The crossover point is not evident in any way.

PSE-144 launch update

PSE-144 is nearing the launch of the first run, which is now closed. Orders will ship in around four weeks. New orders will begin around May.

Here you can see one of the prototypes being tested:

The prototype is being tested here at a height of 3m into the air. At this height, it does prove a challenge to get the mic high enough. These measurements are used for the crossover and the additional height provides greater resolution due to a longer measurement window.

In these photos you can see one of a number of prototypes made in the process of perfecting the manufacturing process. It's not obvious in these photos, but there are some imperfections that are being corrected, as a very high standard of finish is expected here. These are being made by a very well established Australian fibreglass manufacturer.

PSE-144 has midrange extension to 200 Hz and horizontal pattern control that approaches the Schroeder frequency in domestic listening rooms.Although it's difficult to evaluate a speaker with no bass extension, when listening to a live acoustic recording at the end of a weekend of testing there was an impression of live dynamic realism - a very clear, articulate and uncoloured sound.

Coming soon:

  • There will soon be opportunities to hear this speaker in Melbourne
  • New orders due to begin around May
  • Contact Red Spade Audio regarding pricing, lead time or other questions

April 5, 2014

AV8 directivity sonogram

Here we can't provide the normal 6 dB down line due to sharp diffraction dip that occurs on axis around 2.7k. This quickly disappears off axis and so in this normalised sonogram it does skew the perspective a little. In practical terms, although the audibility is not likely a real issue, listening a few degrees off axis removes the dip.

If more smoothing is used, or a shorter time window with the measured (caused by gating where the speaker is not elevated high outdoors), then this issue becomes spread out over a broader range.

Overall we see good directivity performance with a gradual narrowing trend towards 3k above which the directivity is fairly constant before narrowing at the top end.

PSE-144 testing

Although PSE-144 is light due to fibreglass, it did prove a challenge to test on my turntable given the height of the platform and the depth of the horn. The mouth is placed at the pivot point of the turntable.

PSE-144 is nearing release of the kit version. Shown here is one of a number of fibreglass prototypes being tested.