Kenzie OG

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.

Generation 2 of the Kenzie OG 

The close of 2021 has brought out more than 18 months of a global pandemic. During these challenging times, we at ampsandsound strengthened our development efforts resulting in new generation of our classic amps.

2022 adds the ability to chose 8/100 or 32/300 for output impedances when ordering.

Though octal input tubes provide a romantic character that had defined the ampsandsound house sound, reminiscent of 1950s HiFi, the downside to this approach is a reduced noise floor and dwindling NOS options. With ampsandound moving to a 9pin front end, performance has been increased, NOS tube rolling has become nearly limitless, and yet we were able to enhance the sweetness and tone we are known for. The 9pin front end allows vastly increased options for tone rolling to find your balance and preference.

With our front end's new development, we have improved our amps further, including both subtle and significant changes alike. Notable takeaways include increased power output, reduced noise floor across all our amps, increased bandwidth.

Supplied Tubes:
Input tube: 5751 or 12AX7
Output tubes: 1626 or VT-137

Cathode Bias/automatic bias allows for easy tube changes without adjustment.
Compatible with 8 ohm-200 ohm headphones using the Low-Z 1/4″ jack.
Headphones above 200 ohms will benefit from using the Hi-Z   1/4″ jack.

Wood Chassis dimensions:10.75" Wide x 8.75" Deep

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

32ohm power: 350mWatts RMS @ 1khz
Frequency bandwidth 20hz -3db to 12khz -3db full power
Noise on 32ohm tapp @ 440uV RMS

300ohm power: 480mWatts RMS @ 1khz
Frequency bandwidth 20hz -1db to 18khz -3db full power
Noise on 300ohm tapp @ 680uV RMS

THD .1 Watt @ 0.888%
THD .3 Watt @ 1.654%
THD .5 Watt @ 2.245%
THD MAX @ 2.705%
Noise ACC=.065mV

Compatible with nearly every headphone.

Power and Noise specs are dependent on tube selection.

All ampsandsound amps are handmade in Southern California with custom hand-wound output transformers and U.S. sourced parts.

Our amps are hand-made by a small team with quality being our first priority.