Passive Bookshelf Speaker (A3SP2)

Absoutely. These speakers were originally designed for audiology speech tests and are used for hearing diagnostics so they must and do provide excellent near-field response. If they fit on your desk, and you can position yourself properly which may include tilting them up (with the adjustable feet) so your ears are on-axis, they will be perfect for a home studio—but don’t turn it up too loud and take ‘quiet coffee breaks’ so you can have years of great production ahead of you.

Our speakers cross over at 3300-3400 Hz with a smooth roll-off filters. The advantage of this is that there are less components between the music and you. As a consequence of using less components, there is also less phase disturbance. The drawback is that it does mean that that both the woofer and tweeter are contributing to the sound together, expecially near the crossover frequency, and this can (and does) cause vertical off-axis problems. We addressed this by using a large 80mm vertical tweeter which acts more like a ‘line-source’ than a ‘point-source’ given better veritical dispersion and also by putting the tweeter as close as we dared to the woofer while maintaining the rigidity of the front facia. We have made our best compromise. In addition, these small bookshelf speakers are designed for smaller rooms where the direct-to-reverberant transition happens near the speakers (due to early wall reflections) which also helps reduce the area where this problem exists. Still, if you are planning to sit very near the speakers (e.g. in a home studio environment) it is best to sit with you ears at the same level as the speakers. We considered but didn’t use a ‘coaxial driver’ because the sound of the tweeter and woofer combination was, for us, a more important factor so we minimized the problem as best as we could.

For our A3HF1 the cables are optimized for the system. This means that we can provide small light and flexible cables that you can hide. One system engineering trick we use is to not to use low impedance bass drivers. Since the majority of current goes to the woofer, using a higher impedance wooder reduces the current. In this case the power is delivered more by voltage, which is less sensitive to wire guage. It will still be loud enough, don’t worry.

We tried several versions of internal bracing during development but each time it reduced the internal volume and we lost bass response. In a small system this was not acceptable. After much trial (and error) we moved to a sandwhich design using stiffer high density fiber board (HDF) replaceing the medium density (MDF) from the original design, increased the wall thickness to a full 18mm, and added a rubberized layer on the inside of cabinet. This was able to damp the cabinet while only increasing the outer dimensions by 3mm. So we just solved that problem another way and the bass response thanked us for it.

We use a 48 kHz internal sampling rate. We made this decision for two reasons: (1) almost all mastered recordings are made in 48 kHz, so while upsampling these doesn’t hurt the original signal at all nothing is really gained by artificially doing this, (2) 48kHz allows the modern DSP processing (e.g. frequency filtering, bass enhancement, speaker current mointoring) we used in our designs. The argument for using a higher sampling rate like 96 kHz is that it is easier to make the final DAC output filters (which must be analogue) at because they can have shallower slopes. We believe we have made superb output filters for the 48 kHz signals so in the end using 48 kHz was a better choice for us.