Kenzie OG

Coupling Capacitor
Output Impedance

Like many of our products, the Kenzie headphone amplifier evolved from our earlier designs – in this case, rave reviews about the SE-84’s headphone section. The inevitable question followed; why didn’t we build a dedicated headphone amp?

Why indeed?

After some research, we came to the conclusion that a headphone amplifier building on the much loved Darling circuit was the right choice for us. The outstanding performance of the Kenzie headphone amplifier is made possible with custom wound ultra-high quality output transformers providing amazing frequency extension.

The Kenzie does not use a voltage network, and has more than enough power to drive even the most difficult headphones. We chose 32 ohms and 600-ohm output taps to allow use with the widest variety of headphones; everything from Grado Labs, HiFiMan, Audeze, MrSpeakers, Sennheiser, and Beyerdynamic.

The Kenzie showcases the transformers on the chassis to frame in the unique 1626 single-ended tubes. We have included an ALPS volume pot to allow attenuation and simplify the signal path.

The Kenzie is one of the sweetest-sounding headphone amplifiers on the market. The 1626 is commonly referred to as the “Poor Man’s 300B”; offering a similar level of warmth, texture, and soundstage depth.

The 1626 is a WWII-era tube that was used as a transmitter tube in radar installations. The design is shy on pure output, but offers layers of texture and drive, and is paired with a massive choke and robust output transformers for ultra-quiet operation. As with all of our products, parts selection was crucial during this build and each chosen not for price, but for best quality and synergy.

Supplied Tubes:
Input tube: 12SL7 or equivalent
Output tubes: 1626 or VT-137

Cathode Bias/automatic bias allows for easy tube changes without adjustment.
Compatible with 32 ohm-300 ohm headphones using the 32 ohm 1/4″ jack.
Headphones above 300 ohms will benefit from using the 600 ohm 1/4″ jack.

Headphones driven successfully or tested with the amp include, MrSpeakers Ethers, MrSpeakers Ether Cs, Audeze LCD-2.2F, Audeze LCD-XC, AKG240, AKG701, Sony MDRV6, Sennheiser HD650, Sennheiser HD800, Beyerdynamic T1-600 ohm, HIFIMAN HE400i, HIFIMAN HE-400, HE-400S, Grado Labs SR-60, RS1i

The Kenzie is handmade in Southern California with U.S.-sourced parts and custom hand-wound output transformers.


Input impedance is 10K ohm with alps pot
Input Sensitivity 520mV for full power out.

32ohm power: 250mWatts RMS @ 1khz
Frequency bandwidth 20hz -3db to 12khz -3db full power
Noise on 32ohm tapp @ 440uV RMS

300ohm power: 300mWatts RMS @ 1khz
Frequency bandwidth 20hz -1db to 18khz -3db full power
Noise on 300ohm tapp @ 680uV RMS

Please look at our news section for feedback from owners of the Kenzie headphone amplifier.