Monoprice Big Bang II of 2018: two Open-Backs and two Cavalli Amps

Surprise, surprise, Monoprice is back with Big Bang II! Their first big bang of 2018 gave us two closed-back planar-magnetic headphones and a quarter of headphone amps from the tiny to the twenty-pounders! Their second Bigg Bang of 2018, the Spring edition, brings two curiously named headphones and a couple of …Alex Cavalli co-branded amps!


Monoprice is back with two new dynamic open-back headphones with the rather curious names of M600 and M650. Totally not HD 600 and HD 650 🙂 Not a lot of information is known about these yet, but the Monoprice product pages for these, PIDs 30864 and 30865 reveal these specs:

  • open-back dynamic headphones
  • 50mm drivers
  • 64 ohm impedance
  • 98 and 100 dB Sensitivity
  • the M650 listing says 2 meter cable length
  • cloth and leather earpads included
  • prices $130 and $150 respectively
  • release estimate May 31st in 2018

The M600 and M650 product descriptions poignantly state, mayhaps to distinguish between these and other Monoprice products that obviously share origins with other products:

“designed from the ground up for the Monolith series”

The M650 “features a larger earcup”, and have an extra 5 Hz in their frequency range versus the M600 (15-20K versus 20-20K)


A big get for Monoprice as they continue to push their Monolith series as something of a premium value, two new products co-branded with Alex Cavalli, with a late June 2018 release estimate.

For an affordable $100, they offer the “Monolith Liquid Spark Headphone Amplifier by Alex Cavalli”, PID 33304. These have RCA on the back, and with a headphone output on the front. In the “Answers” section, a Monoprice “Staff” person said when asked on “output impedance”:

“Less than 0.1 ohms and most likely less than 0.05 ohms”

The other new entry is starting at $700, it is the “Monolith Liquid Platinum Headphone Amplifier by Alex Cavalli” with PID 33305. It is a Balance version of the Cavalli Liquid Crimson. RCA and balanced connections on the back, and headphones outputs on the front.