One thing up front: the HD 599 is open-back. The outer face of each cup is a grille, sound leaks out, and anyone sitting close will hear what you are playing. That is not a fault, it is the trade the open design makes for soundstage. It is a pair that stays at your desk.
Key features
Open-back, over-ear
A 38mm driver sits behind an open rear chamber, so sound is not trapped and reflected inside the cup. Frequency response runs 12 Hz to 38,500 Hz, and total harmonic distortion is under 0.1% at 1 kHz, 100 dB SPL.
50 ohm impedance
50 ohms is moderate, with a sound pressure level of 106 dB SPL (1 kHz / 1 Vrms). A phone or laptop will drive it to volume, but a small DAC or headphone amp gives better grip on wide-dynamic material such as classical and live recordings.
Two detachable cables
The box includes a 3 m cable with a 6.3 mm straight plug and a 1.2 m cable with a 3.5 mm straight plug, plus a 6.3 mm to 3.5 mm adapter. Desk use and portable use are both covered, and a damaged cable can be replaced on its own.
250 g with velour pads
250 g, velour ear pads and a padded headband. The open structure keeps the ears from getting hot, which counts through a Hong Kong summer.
Specifications
| Item | Specification |
|---|---|
| Transducer principle | Open |
| Driver | 38 mm |
| Ear coupling | Over-ear |
| Frequency response | 12 Hz – 38,500 Hz |
| Impedance | 50 ohms |
| Sound pressure level | 106 dB SPL (1 kHz / 1 Vrms) |
| THD | < 0.1% (1 kHz, 100 dB SPL) |
| Cables | 3 m with 6.3 mm straight plug; 1.2 m with 3.5 mm straight plug |
| Adapter | 6.3 mm to 3.5 mm |
| Weight | 250 g |
Who it's for
- Listening at a fixed spot at home or in a private office, where soundstage and imaging matter.
- Mixing and editing reference work, where a less congested presentation helps.
- Anyone who wants detachable cables so a worn cable can be swapped rather than binning the headphones.
- Who it's not for: commuters. Open-back headphones isolate nothing. Traffic and train noise comes straight through, and the people near you hear your music. They are wrong for the MTR, a library or an open-plan office.
Warranty and delivery
International version · 10-day exchange if faulty · 100% brand new · Viewing by appointment at our Kwun Tong shop, see the warranty policy for details.
Non-TV items are delivered by SF Express (freight collect, paid by the customer), or collected at our Kwun Tong shop (free, 11:00–19:00). For other couriers or delivery to Macau, please WhatsApp us.
FAQ
Q: Does it really leak that much sound? A: Yes. The open design lets air and sound pass through the back of the cups, and someone a metre or two away in a quiet room will hear it. If you need isolation, choose a closed-back model.
Q: Will a phone drive them? A: At 50 ohms and 106 dB SPL, a phone or laptop headphone jack will reach listening volume. A small DAC or amp gives more control on demanding material.
Q: How many cables are included? A: Two, a 3 m with 6.3 mm plug and a 1.2 m with 3.5 mm plug, plus a 6.3 mm to 3.5 mm adapter.