Tuesday, February 7, 2012

Improving the sound of your digital music - Part IV: Audeo PFE 132 Perfect Fit Earphones

In Part II: Setting the reference baseline, we performed an A/B comparison test to measure the degradation from our reference system, with uncompressed digital copies played back through standard iPod earbuds. In Part III, we tested the iFrogz Spectra Ear Buds.)
Audéo is the audio division of Phonak, a Swiss manufacturer of hearing aids which traces its origins back to 1947. From their experience aiding people with hearing loss, Audéo designs the "Perfect Fit" earphones to protect users from incurring hearing damage as a result of excessive sound levels. As one might expect for $239.99, the Audéo PFE 132 which we tested for this review is not just another "one size fits all" earbud replacement.  Audéo includes a kit that lets you pick the ear tips that provide the best fit, as well as the audio response characteristic that best suits your taste.

The PFE 132 employs a single balanced armature design, which Audéo specifies for a frequency response of 5Hz to 17 kHz. The PFE 132s come with two pair each of two different user-replaceable acoustic filters, along with a tool that you use to change them out. Audéo says that the gray filters enhance perception of mid-frequencies, with a sensitivity of  -109dB Sound Pressure Level (SPL)/mW at 1kHz. The black filters have a sensitivity of -107dB SPL/mW at 1 kHz, and are designed to enhance perception of bass and treble. Impedance of the PFE 132s is nominally 32 ohms. The 1.2 meter cord is encased in a thicker, more rigid plastic coating (compared to iPhone earbuds) which retains its coiled shape and avoids tangling.

Audeo supplies three pairs of silicone ear tips, one each in small, medium and large sizes. An additional pair of medium-sized "Comply™" foam tips are to designed to provide greater filtering of ambient noise. Other accessories included with the PFE 132s are an ear tip cleaning tool, optional "Perfect Fit" silicone ear guides to ease routing of the wires that are worn around and behind the ears, and a soft carrying case.

We sampled our reference material first with the pre-installed gray filters, and medium ear tips. We then changed to the black filters, which in our judgment provided a more uniform response across the audio band. Though the medium ear tips fit comfortably, we switched to the large size which held the earphones more firmly in place, and provided a more complete seal that should enhance bass frequency response.

Test of Audeo PFE 132 Perfect Fit Earphones
We gave the results of each test a subjective numeric grade.
  • 10 points: Indistinguishable from the reference.
  •   9 points: High-quality reproduction with all the essential elements of the recording, and only a slight loss of accuracy compared to reference.
  •   8 points: A quality playback, but loses some elements of the reference.
  •   7 points: Listenable, but alters the original or lacks significant characteristics of the reference.
  •   6: Fails to retain many elements of the original, or distorts the reference material.
Introduction - Male vocals
Reference system:  The narrator's voice has a deep chesty resonance in the reference, with a warm, very realistic sound. Each breath as he speaks is audible in great detail, lending a high sense of realism, as if he were there in the room with the listener.

PFE 132: 8.5 points. Not quite the full chest resonance imaging of reference, but close. Accurate and uncompressed.

High Resolution
This is a female vocal of Spanish Harlem, performed by Rebecca Pidgeon. The reference has deep bass in the opening, with an airy, full-range and detailed quality to Rebecca's voice. The shakers in the distance are very detailed, conveying a realistic sense of space, while the violins are reproduced without any sense of excessive brightness. An acoustic guitar sounds very realistic and warm.

PFE 132: 9 points. Warm, sweet sound. Excellent reproduction of bass at opening. Exceptional reproduction of Rebecca's voice. A full image is conveyed which details the echo of the soundstage, and each of Rebecca's breaths. Shakers off to side and back of head. Piano slightly bright.

If I Could Sing Your Blues, with female vocalist Sara K. Track opens with a trumpet in the distance, to the right and conveying a sense of a larger space. Very natural and realistic, Sara K with a wide range vocal range. Drums in the rear of the studio on the left, with detailed cymbals.

PFE 132: 9 points. Sara K is properly imaged up front and center, trumpet properly off to right and at a distance. Drums and cymbals emerge in far background, while Sara is center stage. Excellent reproduction of the range of Sara's voice. Cymbals slightly less ethereal than reference.

Maiden Voyage is another female vocal, with Brazilian singer Leny Andrade. The opening has deep bass, conveying the full body of the instrument, combined with detailed and airy cymbals to the right. Realistic piano contributes to a broad and deep soundstage, with excellent imaging of each instrument.

PFE 132: 9 points. Nice deep resonance on bass, depicts both the body and strings. Piano just slightly more accentuated and brighter than reference, but otherwise realistic. Light and airy cymbals retain detail. Some loss of depth and size of soundstage.

Midrange Purity
Grandma's Hands is an acapella piece with male vocalist Livingston Taylor. Finger snaps are detailed, voice is full and realistic in the reference.

PFE 132: 8.5 points. Realistic finger snaps, but slightly muted compared to reference. A pleasing reproduction of male vocal, with superb detail of each breath.

Correnteza, by Brazilian singer and guitarist Ana Caram was recorded in a church, portraying the illusion of a rain forest filled with bird sounds. The reference immerses the listener in another space, with high frequency detail of bird sounds and realistic effects of water dripping. This is a very detailed, high-resolution vocal. The rhythm of of the drum has deep, full-body harmonics. There is a soft triangle detail at the end of the track.

PFE 132: 9 points: Overall impression of excellent clarity, but in a more narrow image of the soundstage than the reference. Cello is clear and deep. Each instrument stands out distinctly in the mix, with a balanced, full reproduction from low bass of the drum beats to high frequency details.

This track features the Fred Hirsch trio, piano, drum and bass, on Played Twice. Opens with soft drum hits to the right rear, followed by piano and deep bass plucks. A great amount of detail is reproduced in the cymbals, with full harmonics, air and transients. Realistic, full piano sound.

PFE 132: 8.5 points. Reproduction of this track on the reference loudspeakers is an exceptionally realistic portrayal that distinctly shapes each instrument in the trio, with accurate imaging that creates the sensation of placing the listener in the studio. The PFE 132s reproduce each instrument with excellent fidelity to the reference, but the in-head experience inevitably transforms the space to a smaller, more constrained environment. There is some loss in the deep bass that you can both hear and feel in reference.

Ask Me Now is a tenor saxophone solo, performed by Joe Henderson in a large recording studio. The reference blasts from the speakers to the right of center, with a full, realistic, three-dimensional body resonance. The echo in the recording studio comes through in playback, giving a sense of the size of the space. Each keystroke and breath is clearly detailed.

PFE 132: 9.5 points. Conveys full, deep tenor notes and feel of sax. Excellent reproduction of back wall reflections that define the space, great detail in key strokes.

Visceral Impact
Sweet Georgia Brown by Monty Alexander, with two drum sets, and both an acoustic and electric bass. Opens with piano on left, audible mutterings of Monty Alexander, realistic full drum set to the right rear. Airy cymbals from second drum set to left rear. Clear sounds of both acoustic and electric bass. Dynamic soundstage filled with horn blasts.

PFE 132: 9 points. Clearly delineates every instruments in the ensemble: electric bass on right, acoustic in left but slightly attenuated, excellent rhythm and pace with piano and airy cymbals, along with horn section in background. Lacks the distinctive physical impression of the piano portrayed with reference loudspeakers.

Rhythm and Pace
Johnny Frigo on jazz violin performing I Love Paris. Opens with electric guitar to the right. Airy cymbals and sweet sound of violin. Deep notes of electric bass keeps rhythm to the left. Excellent imaging of high-hat cymbal. Very deep kick drum with visceral impact. Saxophone on left fills soundstage while cymbals and guitar keep pace on right. Very dynamic!

PFE 132: 9.5 points. Conveys sound of space and Frigo's violin right out of the gate. Hits high notes while also keeping bass rhythm clear and realistic. Plucks and warmth of electric guitar reproduced with excellent fidelity. Great cues of room size. Excellent bass response during quiet passage. Kick drum clear along with dynamics of cymbal shimmer. Sax emerges with full, deep, clean sound. Superb detail of cymbals. Visceral impact of violin with kick drum, though slightly less distinct imaging. No brightness on high notes.

Vivaldi Flute Concerto in D. Wide dynamic range with deep bass notes along with high fluttering notes from the flute. Can hear detail of the musician's breaths. Excellent sense of space and realistic ambiance.

PFE 132: 8 points. Smaller sense of space. Flute not as clearly focused as the reference. Great detail in solo, but some smearing of the image from echo on the high notes not heard in the reference. Excellent low end response. Clear imaging of each instrument.

Holographic Imaging
Festival Te Deum is a performance by the Westminster Choir in a large cathedral (60' W, 225' L, 90'H) with pipe organ, recorded with a single microphone elevated 35 feet high. This track is challenging for a full-range loudspeaker to image the large space, and presentation of the wide, yet detailed dynamics. The reference system has excellent depth, and fills the room with images of the choir as a whole, while retaining the individual voices.

PFE 132: 9 points. Accurate depiction of opening with air of organ and image of choir. Retains detail in quiet passages. Excellent clarity of individual singers. Manages peaks of choir well without audible distortion. Impressive imaging and sense of space and organ harmonics. This track can be overwhelming with loudspeakers, even more so in-head, but PFE 132s encourage extended listening.

Stravinsky's The Royal March. This is a very dynamic track, with very deep notes from the kettle drums to the high frequency transients from violins, flutes, and trumpets.

PFE 132: 8 points. Kettle drum moves into background compared to reference, but otherwise excellent detail of individual instruments. Good dynamic range with excellent low end and clear highs.

Bass Resonance
This is a single standup bass recorded 3' from the microphone. The reference system produces a full, realistic sound of the body of the instrument, along with the string plucks, that never fails to shake something in the room before finally trailing off in a gentle fade out.

PFE 132: 8 points. Retains a good sense of the body of the bass on low note harmonics, detailed plucking of strings. Excellent harmonics.

Dynamic Test
This is a wide dynamic range solo drum recording. The snare and kick drum open relatively low in volume, with detailed cymbal hits and clear, deep drum kicks. Excellent holographic imaging of the complete drum kit, along with height of the cymbals. Incredibly realistic!

PFE 132: 9 points. Excellent detail of drum kit. Kick drum impactful. Beautiful imaging of cymbals and clear, deep drum hits.

For the 15 reference tests, the Audéo PFE 132s (with black filters) achieved an average score of 8.77.  The overall listening experience is of very high fidelity, with only a few characteristics that fell short of the reference. Two of the three lowest (8 points) scores were associated with bass response, where earphones are at a disadvantage, since it is impossible to reproduce the reference sound from good full-range loudspeakers that can be felt as well as heard. 

The PFE132s are very comfortable to wear, though we would probably switch back to the medium ear tips for more casual listening. It is good to be able to choose from the different sizes and materials for different purposes, an option that would appear to be a relatively inexpensive enhancement that even lower cost manufacturers could easily adopt. With the thicker plastic cord of the PFE 132s, it is a simple pleasure to be able to actually lay the earphones down on a table and pick them up without any untangling whatsoever. Other manufacturers should pay attention.

We performed a brief test of the PFE 132 microphone, by recording a message on an iPhone application and comparing it to the result with the standard iPhone earbud/mic combination. On the iPhone recording the PFE 132s produced much clearer and more accurate sound. However, in use making telephone calls with an HTC Thunderbolt (which has poor audio quality with its built-in mic), the result was poor.

If you are looking to have a high-fidelity personal, portable musical experience, one that more closely resembles a high-quality home system, an investment in a good pair of earphones like the FPE 132s is highly recommended. The difference in sound quality compared to standard earbuds is substantial, justifying spending at least as much on how you hear your music as you do on how you store it.

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