Where there is still bass presence and a dash of treble sparkle where it is needed. Instrument separation is great since the frequencies don’t tend to bleed into each other. So details tend to become quite clear, and pleasurable. As with all the headphones sharing this venerable driver, the KPH30i offer far more than they cost. Until then headphones had only been used in communications applications. In 1958 the design was introduced at a hi-fi trade show in Milwaukee, and audiences approved of it. Soon after the trade show, Koss went into business manufacturing and marketing stereophones from his basement apartment. The technology was imitated by competing manufacturers. [5]

In the late 1970s, to accommodate rapid growth, Koss moved to its present location on the north side of Milwaukee. [ citation needed] The Porta Pro are warm-sounding headphones with far more prominent bass than the KSC75. Where the KSC75 have more upper energy and seem slightly more resolving, the Porta Pro have more presence, although with bass heavy music they can tend towards boominess and bloom. I find the Porta Pro to have superior sonic balance and are a better match for my tastes. Like the Porta Pro® Classic headphones, the Porta Pro® Wireless Bluetooth headphones have adjustable temporal pads to relieve pressure on the ears. Its lightweight, open-air cushions for hear-through sound keep listeners aware of their surroundings while delivering exceptional sound performance. Oxygen free copper voice coils and dynamic elements allow the Porta Pro® Wireless Bluetooth headphones to deliver rich bass and a remarkably wide frequency response.Having a dual entry connection also has it’s benefits, in that it makes it more convenient to rewire them, and turn them into a balanced headphone, to use them with a balanced DAP/DAC, in case that’s what you want to do down the road. Portability

The diaphragm receives an extremely thin layer of titanium bonded to its surface. Titanium is a popular choice for driver manufacturers as it has the highest strength-to-weight ratio of any metal. Titanium sure does make the driver super shiny! The KPH30i is a headphone that you might think you can easily find if you would rummage through a computer parts bin, but it truly is a gem in the rough. Although it’s not exactly portable, with the solid and unfoldable frame, it’s light enough and durable enough to be thrown into a bag when you need to bring it on some trips. Koss lists the first Key Feature of the KPH30i as “spacious sound & deep bass.” While “deep” may be debatable, this is a reasonably accurate depiction of what you can expect. The untreated Koss driver typically delivers a low-end focus, and the KPH30i are no exception. The very depths of the sub-bass aren’t really reproduced, but overall the bass region is articulate and conveys solidity and weight.

My biggest gripe with the Porta Pros was their headband adjustment. What’s left of my hair always seems to get caught in them and their headband adjustment doesn’t seem to be able to stay in place. Headphones with a dynamic element positioned just outside the ear, connected to a tubular port structure that inserts into an expandable cushion