C336 Setup and Measurements

I wired the speakers up with Blue Jeans Canare 4S11 cable. Source was a Denon DVD-3910 universal player through a Denon AVR-2307CI pushing two Seymour AV Ice Block 5001 monoblock amplifiers. I was sitting about 8 feet from the speakers with the pair about 6 feet apart. The speakers were no closer (and in most cases quite a bit farther away) than 2 feet from any boundary. I've mentioned before the vampire spikes on the Classia C336s - they are outrageously long. That being said, there was both good and bad points to this length. The first obvious drawback is the danger of exsanguination from being impaled on one. The upside is that these were, with the exception of a professional outrigger solution like the offerings from Soundocity, the easiest spikes to adjust and level. What normally takes a lot of trial and error took moments - mostly because the speaker was practically floating off the floor. The only downside to that is that the outriggers actually looked like they were floating off the floor! They completely hid the spikes. This gave the spiked Classias on my medium pile carpet a sort of "penguin-eske" look.

As I often do, I grabbed my yello - the eye CD as I started experimenting with toe-in. The speakers sounded, I thought, remarkably good pointed straight out though some of the center imaging was a bit thin. The soundstage seemed wide and pans mostly convincing. I experimented some more with placement including pointing the speakers directly at me and just and a few variations between. The more I pointed the speakers at me, the more solid the center image became though often at the expense of soundstage width and high end fatigue. I settled on a modest toe-in of around 15 degrees. One thing I'm going to recommend regardless of your flooring type is that you determine your toe in before you add the spikes. The spikes make moving the speakers very difficult and I don't recommend it. The only problem I really had with determining toe-in was a unique one for the Classias - the top. When I really want to get anal about the whole thing (and what Audioholic doesn't get anal about audio every once in a while?) I put a laser pointed on top of each speaker just to make sure I've got them pointed EXACTLY where I want them. Well, with the slanted top of the Classias, this isn't possible and it really made determining the exact orientation a bit more difficult. Even when I haven't busted out the laser pointer, I'm usually lying my arm across the top of the speaker and using that as a guide - again impossible with the C336s. This is just another reason why you want to make sure of your positioning before you install the spikes.

Measurements & Testing

For laboratory measurements I used the Sencore SP395A FFT Audio Analyzer and a Sherbourn 2/75B amp, I measured the Infinity Classia C336's in room on and off-axis frequency response with 1/12th octave resolution.

C336 1 Meter Frequency Response (1/12th Octave) On Axis
Note: this is NOT a 1 watt measurement

C336 1/2 Meter Frequency Response (1/12th Octave)
Pink - On axis, Orange - 15 degrees off axis, Yellow - 30 degrees off axis

As you can see, the Classias have a fairly flat speaker response with an on-axis bump in the high end. I played with the mic positioning quite a bit and determined that just below the 4" midrange was the best location. This works out well as from my seated position the "sweet spot" on the speaker is just about perfectly located at ear height. These speakers exhibit a much flatter response off axis rather than on where the high end is a bit strong. We recommend you sit off axis from the speakers in order to reduce these affects.

C336 Impedance

The Sencore consistently measures impedance one ohm low. Dr. Floyd Toole of Harman has stated that it’s a Harman requirement to have no speakers dip much below 4 ohms which is clearly evident in the design of this system. These speakers could benefit from additional amplifications but as long as you keep your room a reasonable size and your volume levels the same, just about any mid-line receiver should have little problem with them.