Originally Posted by TuteTibiImperes
Interesting, thanks for the link. They both look to have excellent build quality, and I see that the Storm Audio has the fancy web-based configuration tool that looks like it could be useful in setting things up.
I'm still not sure what the additional channels are for. Say you have a 9.1.6 setup, do the other 4 channels on the 20 channel unit go towards independently EQing multiple subwoofers sharing the same LFE channel? What about moving to the 32 channel versions? If it can't decode Atmos at, say, 14.4.14, what are they used for? Can it just matrix speakers in between the discretely addressed 9.1.6 to create extra virtual channels?
Obviously the ISP 3D.16 ELITE
processor and ISP 3D.16.12 ELITE
receiver can accommodate 16 channels for 9.1.6 Dolby Atmos.
When you move up to the ISP 3D.20 ELITE
processor, the 4-XLR expansion module lets you accommodate 20 channels for 9.4.6 Dolby Atmos including 4 subwoofers and one extra XLR output that can be used for either Near-field Mid-Bass Modules
or Tactile Transducers
. This is the ideal setup for most people with a single moderately sized home theater:
It allows you to reach the optimum smoothing out of frequencies response and room modes (see Harmon paper by Welti & Devantier below) by using four subwoofers instead of only one or two on most processors.
It allows you to increase "chest slam" in the near-field 50 Hz range by incorporating and adjusting Mid Bass Modules right behind the main LP (see Below), and/or
It allows you to increase Tactile Response below 16 Hz by incorporating and adjusting tactile transducers on the seating to augment the ULF frequencies (see below)
The Ultimate Frequency, Pressure and Tactile Response Thread
The Ultimate Four Octave Experience. Thats what I call it. My goal is to have perfect, balanced, response of all three LF/ULF components, Frequency, Pressure, Tactile.
You can't just run Near-Field Mid-Bass Modules
and Tactile Transducers
off your other subwoofer feeds because the time delay distance is zero. Also you would want to be able to adjust the level of SPL on the Mid-Bass Modules to augment the pressure at the seating position without overwhelming the frequency response of the whole system around 50 Hz. The same is true of the tactile transducers. You would want to be able to adjust their amplitude up to where it augments the experience of ULF without calling attention to themselves. Having the extra channel(s) to independently control Mid-Bass Modules or tactile Transducers also allow you to adjust them on the fly while watching a movie. You can also have different preset levels for you (medium), your spouse (low), or the kids (highest).
An ISP 3D.20 ELITE
processor could also be used for a 7.1.4 system in your home theater, a 5.1 system in your family room, and a 2.0 Sonos whole house audio system (20 channels total). Remember that the Storm ISP processor controls are web browser based. So an iPad in the Home Theater, plus an iPad in the Den or a phone app will control all three systems even though the processor and amps are hidden in an equipment closet in one location.
Low-Frequency Optimization Using Multiple Subwoofers*
TODD WELTI AND ALLAN DEVANTIER
Harman International Industries
One of the authors  made an in-depth investigation to determine which configurations were optimal in a rect- angular room with the typical seating arrangement shown in Fig. 4. Investigations were based on numerical model- ing of the space as well as an actual measurements in the room, which were found to be in reasonable agreement. Instead of using a flat magnitude response target, as gen- erally has been used in the past, metrics based on seat-to- seat variance were used to characterize performance. A number of different room dimensions as well as two dif- ferent seating configurations were also investigated, again with the same overall results.
By analyzing over 100 000 subwoofer configurations it was shown that for configurations of one to four subwoof- ers, location at wall midpoints is optimal. Fig. 5 shows some of the configurations tested, starting with one- subwoofer configurations and ending with 18-subwoofer configurations. Four subwoofer at the wall midpoints (configuration 11) was the best practical configuration in terms of MSV. Two subwoofers at opposing wall mid- points (configuration 6) was nearly as good and also of- fered stronger low-frequency support. Configurations with more than four subwoofers were not found to be advan- tageous, especially when cost is factored in.
Mean Spatial Variance (MSV)
The variance of the sound level2 in dB as a function of the seating location (typically four to six seats) is calculated for each fre- quency, and from this the mean variance is calculated. This is a measure of seat-to-seat consistency in the ampli- dude response.
Fig. 6 shows MSV as a function of room length and width, calculated over a 3-m by 3-m grid of 16 seats centered in the room, for six subwoofer configurations. Room dimensions range from 4 to 9 m, and the ceiling height is 2.7 m. Similar results were obtained with 2.4-m and 3.0-m ceilings. It can be seen that the performance of a given subwoofer configuration depends to some degree on the specific room. While optimizing room dimensions without a knowledge of subwoofer or seating area con- figurations is next to meaningless, choosing a subwoofer configuration and room dimensions for a known seating configuration can be very useful.
Nearfield Ported MBM for Increased Mid-Bass Tactile Response
Crowson Tactile Motion Actuators
When you move up to the ISP 3D.32 ELITE
processor, the 16-XLR expansion module lets you accommodate 24 channels in your home theater for 22.214.171.124 (9 base + 4 subs + 6 Atmos + 5 Auro). This would allow you to play 9.4.6 Atmos movies and 7.4.5 Auro music (via up mixer) using speakers in their optimum locations.
The remaining channels could be used to array multiple speakers in a larger theater including Mid-bass modules and Tactile transducers, plus an additional 5.1 system in a den, family room or guest house plus a 2-channel Sonos whole house distributed audio system with local subs. You could also do a number of smaller systems in multiple rooms, all controlled by iPads with the equipment in one central location.
Anyway you look at it, this is one of the most flexible and configurable processors on the market. Start with the basic ISP 3D.16 and grow your system from there with additional outputs and enhanced features through expansion boards. It's an integrator's dream and much easier to configure (from what i've been told) than the Trinnov Optimizer.