JL Audio f110 Set-Up & Installation

Before connecting the f110s to my system, I took them outdoors and conducted 1 meter groundplane measurements. I found one of my f110s exhibited excessive cabinet noise below 40Hz at high SPL levels. When I took it inside to test on my A/V system, I found at times the sub would simply oscillate out of control with no input signal. I immediately informed JL Audio of my findings and they not only decisively replaced that defective subwoofer but they insisted upon building me up two brand new ones. I received the second set of subwoofers less than one week later both of which operated flawlessly in my testing.

Moving the f110s around my family room was a bit of a chore for me. Despite their manageable physical size, they were quite heavy as I mentioned earlier. Before placing the f110s into the most practical and useful positions in my room, I referenced their user manual and was pleasantly surprised to find some very solid recommendations not only for placing one sub but multiple ones as well. They show you a chart for placing a single sub in a corner and how moving it slightly away from corner placement will yield smoother sound. They also show that the ideal listening position is around 1/3^rd of the total room length away from the back wall. JL Audio proceeds to expend a full two pages with illustrations on the most ideal locations for placing up to four subwoofers in a room. Their preference for placing two subs favors the front of the room near the main speakers which I can certainly understand as it does have its advantages especially when running stereo subs. This allows you to set a higher crossover point without being concerned about localization issues and thus achieving a more seamless blend and potentially higher impact. In my family room, I have two prewired spots for subwoofers which are diagonally located front left behind my couch and back right near my potted plant in my room as per my illustration. This is also incidentally a recommended placement from the JL Audio user manual as well as our recommended placement suggestions in our article “Multi Subwoofer Connection Guide”.

Calibration

I proceeded to calibrate and level match each subwoofer independently by using all of the options such as variable phase, adjustable and LPF settings. I achieved the best integration with the LPF on both subs defeated and the variable phase set to zero degrees. Since both of the subs were equidistant from my primary listening seat and my RX-Z7 only has one subwoofer output, I used a Cables-to-Go Y-splitter to connect both of them and set the subwoofer distance to the average distance of both subwoofers. Incidentally, JL Audio recommends you dial in the subs as best as possible before engaging ARO or any external room correction device and I am in much agreement on that point. Using the supplied mic positioned at my primary listening seat, I calibrated each sub independently using the ARO system and plotted the results below using LMS.

In-room measurements with (black) and without (red) ARO calibration (1/12^th octave smoothed)

ARO seemed to produce measurably favorable results at the primary listening position where I placed the JL Audio calibration mic maintaining a +-5dB response from 12Hz to 100Hz. These results were quite encouraging until I measured the secondary seat where my mother-in-law often sits (left side couch near the end table). ARO caused a 15dB suckout centered at 32Hz with a Q of about 3.6.

I tried a variety of alternative ARO setups including moving the calibration point to this seat and even midpoint between the two primary seats, as well as only calibrating one sub with ARO. The end results were either worse at that seat or at my primary listening seat. Unfortunately ARO is limited to a single point calibration unlike some of the more advanced systems out there like Audyssey.

I conducted extensive listening tests with and without ARO enabled and found it did tighten things up a bit at the primary listening seat but some bass impact was lost, especially at the other listening areas. As a result, unless otherwise stated, my listening tests were conducted with ARO defeated. My advice here is to experiment with using ARO. At the very minimum it’s a tool to add to your bag of tricks to help you tweak out the best possible sound. As with all room correction systems, results will vary depending on your room and placement conditions.

Editorial Note on Auto Calibration Systems

Having ARO define the response for both subs instead of independently would have likely yielded better results. This can be accomplished by wiring the two f110s in series and setting the secondary sub to “slave” mode. If you experience similar performance trade offs as I did using ARO, this may be worth a try assuming you can accommodate connecting the two subs in this fashion.

Reference Equipment (Showcase Home Family Room)
I used the Yamaha RX-Z7 as the A/V receiver with Blue Jeans Cable 1694 Coax cable fed to each f110 and their 10AWG speaker cables for all of my speakers. The Denon DVD-2930CI was the source and I utilized the RBH Signature SE/R series speaker package with MC-615 in-ceiling speakers for the back channels for a full fledged 7.2 system. Most of my listening tests were conducted in either discrete 5.1 multi-channel (ie. DTS, DVD-A) or via Pro Logic IIx Music Mode for two-channel sources such as CD’s or Net radio.