Headphone Reviews

"LOOP" ( Open 32 ohm SFI )
These were originally picked up for a possible project due to a dead stock driver. I didn't think they were worthy because of their lightish construction, but got bored one night. Start to finish approximately 5-6 hours.

CONSTRUCTION DETAILS OF FINAL BUILD ( 2 trials total this being the second and final one, phew )
These could possibly pass for an off-the-shelf pair these days if you didn't look too close.

Shell is the Pioneer "Loop" SE-MJ31V. Mesh is scavenged from a torn apart plug-in baseboard heater. The larger baffles from some thrift store wireless cans I picked up simply for the pads. Magically the baffles fit exactly! Pads brand new from Plantronics #995 cans. Materials are odds and ends from box of build parts. Original wiring is used.

Removed the original silver plastic disc in rear of cups, and cut mesh discs which fit in the circular recess there almost perfectly. On top of that placed black semi-transparent woven fabric material discs; pulled organic cotton ball filler in cavity.

Larger baffles ( very fragile I found out ) are mounted directly over top of the stock ones, sealing them on with thin layer of putty. On baffle insides I applied a ring of Acoustifoam brand 3-layer acoustic foam---this 3-layer foam has a decoupled dense middle---around the SFI driver to stop reflections and absorb resonances. Then mounted and sealed the driver in place with a built up layer of non-hardening grey crack seal Weather Shield putty ( an environmentally conscious product ). Both the 3-layer Acousti foam and the putty add a bit of weight and resonance control. Cotton tends to bring up details a tiny bit and provide minor resonance control. Directly on the back of the driver is a disc of thin, dense, evenly woven white felt from dust-mask filter replacements. I find this particular felt to help increase details; bring up some of the mids and highs; and tighten up the bass response from the direct damping( quality vs quanitity ).

The completely sealed baffles are quite a bit larger than the original supraaural ones, which allowed me to add the larger, almost cirucumaural, Plantronics pads. Notice these pads are perforated only at the top ear contact point for increased long term listening comfort, and this also keeps bass levels up compared to fully perforated pads.

The top headband padding is from some "Vibe" cheapos I grabbed at one point for some pads, which makes this a creation of 4 separate headphones, plus some odds-and-ends.

Somehow this all worked out according to the make-it-as-you-go plan.

GENERAL SOUND
In general: airyness and close to neutrality.

I find these to be my favourites out of all the ones I have sent in---suprisingly, since they were a not-meant-to-be headphone really. They have decent clamping force; comfortable, large enough pads; and not too heavy to be bothersome. Sensitivity after damping is lower of course. These see about 50/50 use portable and in home.

These retained plenty of details,, with non-piercing highs and decent mids, while keeping a tight fairly well controlled bass---they wouldn't if they were undamped and untamed SFI's in an open shell.

They have a high degree of airyness and to my ears don't feel all that enclosed. The image extends out maybe a foot or two---hard to quantify that. You can test this by putting your hands up to the outer mesh. Soundstage seems decent enough, but the Hackamichi's do better than these in soundstage due to angled drivers and other build qualities.

Overall I find this pair to be the most---dare I say it---"neutral" out of the 3 comparatively. At the very least they are good across the board for my tastes. I find in regards to the highs, mids, and lows nothing seems to stand out or cover over anything else.

Measurements