Pass Labs ready HPA-1 headphone amplifier


We first saw Pass Labs HPA-1 headphone amplifier back in January at CES 2015. This week comes new that it’s finally ready to ship. The HA-1 is being touted by these legendary Californians as a Class A “power amplifier” which cuts no corners, spills no frills and was designed under a spare-no-expense mandate by Jam Somasundram.

That translates to serious attention being paid to a “custom, low-noise shielded toroidal” power transformer feeding a “discreet low noise regulated power supply”.

The press release continues, “The HPA-1’s amplifier circuits are low-feedback, wide-bandwidth discreet designs employing J-Fet input stages and Class A-biased direct-coupled MOSFET output stages. The HPA-1 easily drives headphones presenting loads from 15 to 600 Ohms, particularly excelling on planar headphone designs.”

That’s consistent with Somasundram’s Las Vegas introduction of the HPA-1; that he’d voiced it with both the Sennheiser HD800 and Audeze LCD-X (in mind).

Those lamenting Somasundram’s strictly single-ended approach – two sets of RCA inputs out back, one 6.4mm jack up front – should also consider the Pass Labs unit’s possible prowess as a high-end preamplifier. The RCA socketry can be switched over to variable output from the unit’s front panel. Volume attenuation comes a “hefty rotary knob connected to an ALPS Potentiometer”.

Finally, the HPA-1 arrives with Pass Labs’ distinctive brushed aluminium casework in full effect and will sell for US$3500.

Further information: Pass Labs

Jam Somasundram of Pass Labs poses at CES 2015.
Jam Somasundram of Pass Labs poses at CES 2015.

Written by John H. Darko

John lives in the NOW + HERE = NOWHERE. He derives an income from the ad revenues of DAR. John is also an occasional staff writer for Stereophile, 6moons and TONEAudio.

Twitter: DarkoAudio
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  1. John… while this hardly ranks as a disruption to the order of the universe, the “Further information” link to Pass Labs results in nary a whisper about the HPA-1. Go figure, huh?!? Meanwhile, Happy Th– oops, misplaced holiday!

  2. Funny how common that is at high-end audio companies. They do a big publicity blitz and you go to the web address and… nothing. I’ve seen ads in Stereophile that promptly show a URL and then found the URL to be either bad or have no information about the product in the ad.

  3. Here ia a tip for audio companies that still don’t seem to get the web: Make sure your site is ready before you send out the press release, not after.