The HFI-780 was a mid-range headphone from Ultrasone, part of the S-Logic technology line of HFI closed headphones (HFI-580, HFI-2200, HFI-2400 etc). The brand released a successor to the HFI-780 : the Pro 780i.
The HFI-780 was my first “””audiophile””” headphone purchase, back in 2008. I was looking for a first pair of headphones, preferably closed, with a limited budget. Build is sturdy but comfort atrocious, the pleather pads were shallow and very stiff.
○ Release : 2007
○ Current status : Discontinued
○ Type : Over-ear / Closed-back
○ Measured weight : 310g
○ Impedance : 35 Ohms
○ Sensitivity : 100.3 dB/mW
○ Average used price : $50-80
I don’t understand how I managed to keep the HFI780 for a few years as my only headphones. They are way too bassy and bright – strong V-shaped sound with tinny mids, but even the mids are harsh. Bass is not very tight and boomy, but extends well (but not to 20hz).
Midrange is too shouty around 2khz, and then another peak in the lower-treble (6-7khz) is annoying. Lack of treble extension and air. The “S-Logic” technology is beyond my understanding – I don’t hear big difference in sound presentation compared to other headphones.
Having a metal plate covering 80% of the surface of the driver in order to improve imaging would be replicated if it was a good idea, but to my knowledge, only Ultrasone does that. All I hear is a slightly congested sound, quite agressive to my ears, and lacking decent resolution / cleanliness.
Measurements & Resources
Measurements show a midcentric curve, quite far from what I was hearing.
They are known to be very bassy so I suspect Tyll didnt get a good seal during the measurement process. Upper-mids / low-treble sounded much higher in level relative to 1 khz.