Headphone Reviews

Sound Quality
Neutral is a word we love to throw around...but none of us really know what it means with regard to headphones. Thing is, the moment you hear it—or something quite close to it—you know it. The Focal Spirit Professional is simply one of, if not the most, "neutral" sounding headphones I've ever heard. It's not just me either, check out this thread on Head-Fi, or this one on GearSlutz.com (a pro audio gear forum). Most listeners have the same reaction: "O.M.G! These headphones are sooooo neutral!" Thing is, I've also got the Focal Spirit Classic and the NAD VISO HP50 sitting here on my bench and they too sound quite "neutral"...though a bit different.

I'll describe my subjective experiences in a minute, but I think a nice visual would be helpful. Here's a plot of the compensated frequency response for the Focal Spirit Professional, Spirit Classic, and NAD VISO HP50. Plots are aligned at 350Hz.

The first thing to notice is that all three of these headphones have very similar responses. The NADs have their peak at 8kHz vs. the Focals at 10kHz; I think I could hear this with pink noise, but didn't really notice it with music. The area that I could hear clear tonal differences with music is the region between 400Hz and 2.5kHz—the upper-mid-range/low-treble.

The response of the Spirit Classic through this region is basically a straight line with a downward tilt. I heard the Classic as somewhat relaxed and laid-back sounding relative to the other two headphones—"veiled" would be too strong a word, but it's along those lines. The NAD VISO HP50 sounded very slightly sharp or sparkly relative to the other two. The Spirit Professional seemed to do a very good job straddling the line, but in the end I think it's just a tad too forward sounding. I'll remind the reader that all three of these headphones are quite similar sounding and I'm splitting hairs here, but if I had to characterize the differences between the three I'd say: Spirit Classic=Relaxed; Spirit Professional=Neutral; and NAD VISO HP50=Fun.

One area the Focal headphones seem clearly a notch ahead of the HP50 is in terms of their dynamics—the Focal headphones can PUNCH! It's not quite as obvious on the Classic due to it's slightly laid back character, but both these headphones have excellent dynamics. On the other hand, I found the HP50 had slightly better treble resolution than the Focal cans. Cymbals and brushes on drum skin seems slightly clearer and more organic with the HP50, and the top end seems just a tad more open.

Now that I've thoroughly confused you with all this hair splitting I'll take a step back and talk about their neutrality again. A few days ago in this post about the continuing efforts by Sean Olive and researchers at Harman, I posted this graphic showing the still-under-development target response curve vs. the uncompensated responses of the Focal Spirit Professional and NAD VISO HP50.

In the image above the green dashed line is the frequency response at the ear-drum for an absolutely flat speaker response in a room. The black line is the response "preferred" by listeners showing a broad attenuation of the highs and a bass boost. Both the attenuation of the highs and bass boost are, in part, a natural result of placing flat speakers in a room. Harman researchers chose the bass boost filter to start increasing at around 200Hz as that's the typical transition frequency between modal and reverberant responses of a room, and they felt having the bass turn on at higher frequencies tended to muddy the lower-mid-range too much. You'll notice both the Spirit Professional and HP50 have the bass boost start rolling on at about 400Hz. When listening to low male vocals I do think I heard a bit of excess bloom, but just a bit. So, it's possible that all these cans are slightly accentuated in the 200Hz to 400Hz area.

Also, neither headphone does a great job of following the target curve between 3kHz and 10kHz, though the HP50 does a bit better job. In large measure this is a problematic area for headphone measurements where pinna and ear canal resonances come into play and it's very difficult to know exactly what's going on. I will say though that I experience the HP50 as sounding a bit more "open" and it might be due to the somewhat more elevated response in this region.

Hm...I'm still not sure I'm getting the right ideas across to you, let me try this...

The Focal Spirit Professional was designed as a studio monitor headphone for audio pros. My sense is that it is an exceptionally good headphone in that application. Their excellent tonal balance should allow you to EQ with confidence; their very slightly forward nature will prevent you from punching up the presence region (800Hz-2kHz) unnecessarily. The spectacular resolution of the Sennheiser HD 800 would be the better tool for pros looking for an audio microscope to identifying tiny tweets and chirps in the editing process, but frankly I think the Focal Spirit Professional has far better tonal balance and will be preferable in most studio applications.

The Focal Spirit Classic is a great headphone for relaxed listening. The Spirit Professional is not a forgiving headphone, and may be perceived as a bit fatiguing over time. Many audiophile listeners will prefer the relaxed and impeccably even response of the Spirit Classic.

The NAD VISO HP50 remains an excellent choice. While not quite as even and dynamic as the Focal headphones, the HP50 has slightly better resolution and may be a good choice for audio pros who would trade off a small bit of neutrality (the HP50 sounds just a bit uneven) for a bit better resolution. If you have large ears the HP50 will likely fit you better. I feel the better connectors on the cable and slightly fun EQ (which will make bass and treble a bit more audible in loud environments) of the HP50 make it the preferable can for mobile uses.

Summary
The Focal Spirit Professional is an absolutely brilliant headphone for the audio professional. Excellent neutrality make this a trust-worthy headphone for EQing your mix, and it's excellent dynamics and slightly forward sound will keep you from trying to punch up your tracks excessively. Good isolation and lack of sound bleeding out make these a good headphone for studio musicians as well. The finish on these appears to have excellent durability. Four meter coiled cable will allow you mobility in the studio without cable under foot. These are going up on the "Wall of Fame" as the best audio pro cans I've experienced.

The Focal Spirit Classic provides a truly excellent listening experience for the audiophile. This is a neutral headphone with a very slightly laid-back sound stemming from a very slightly withdrawn presence region (800Hz-3kHz), but the overall impression listening to the Classics is of the music being one cohesive whole—these are an extremely even and coherent sounding headphone. Delivering eye-blinking impact when called for, the dynamics of the Classic is superb. Treble resolution is very good and untarnished by any harshness, but like most closed headphones they do leave a bit to be desired in terms of an open and spacious sound. These are going up on the "Wall of Fame" as an excellent sealed headphone for home and office.

The only cautionary notes I have for these headphones is the somewhat small ear-cup and tight squeeze imposed on your head, both these issues lessen as the headphone breaks in a bit with use but folks with large ears and noggin are advised to try the Focals on for fit before purchase. The NAD VISO HP50 may be a better choice. Also the plug on the end of the short cable with remote is rather large and may be difficult to fit in through protective cases on portable devices.

Video

Resources
Focal home page and Classic and Professional product pages.
Head-Fi Threads here, here, and here.
Gearslutz forum (for audio pros) threads here, and here for general pro headphone recommendations—the Focal Pros are starting to get mentioned a lot!