Isabella LFP-V Edition (Discontinued)

Vacuum-tube Preamplifier

Reference-level performance, with natural and emotionally involving presentation. Integrated DAC and headphone support available.


Greatly enhances any high quality, 2-channel music system.

  • Latest generation of our flagship Isabella
    Upgrade available for previous versions
  • Has received glowing reviews and enjoys a cult-like following from customers
  • Custom built to suit your individual system requirements
Product Features
  • 3 sets of analog inputs
  • 2 sets of volume-controlled analog outputs
  • One 6922 dual triode tube per channel
  • Switchable gain (0dB / 12dB) to optimize volume control range for your system
  • Remote volume control for added convenience
LFP-V Features

Learn about the unique design innovations behind our sound.

All LFP Features

Optional Built-in Isabellina DAC
  • 3 types of digital connectivity (Coaxial, Optical and USB)
  • Isabellina Pro Icon Optional Isabellina Pro adds high-resolution playback (24/192k)
  • Eliminates a set of interconnects and keeps signal paths short for optimum sound
Optional Built-in Headphone Stage
  • For headphone connoisseurs, order your Isabella with built-in audiophile-grade headphone amplifier, featuring:
  • Headphone jack on front panel
  • Adjustable gain via Isabella’s tube preamplifier 
  • Can be ordered single-ended (1/4” stereo plug) or balanced (4-pin XLR)


In the Isabella vacuum-tube preamplifier, David Abramson finds his cure for upgraditis...

“Fleet of foot, compact, quiet, reliable and damnably low in coloration and seasoning, I’ve kept her around in preference to many a better known adversary. You’re gonna change amps; you’re gonna change wires- you’re gonna change speakers- hell, you’re an audiophile! So you owe it to yourself for once and all to have a centerpiece- a lynchpin- a piece around which everything else can turn. That’s Isabella!”

Source: Dave Abramson, Stereo Times

Hint: Mr. Abramson ends up purchasing an Isabella for his personal use!

“…few preamps in my experience combine quietude, transparency to source, PRaT and tonal veracity with fuss-free operation and friendly, non-Machiavellian designers in quite the way Isabella does.”

Source: Dave Abramson, Stereo Times

“The tonality of the Isabella is excellent. I firmly believe this is due to the lack of grain from power supply artifacts coloring the signal.”

“The Isabella [combined with the Signature 30.2 power amp] will be tough to beat without spending a lot more money.”

Source: Jeff Dorgay, TONEAudio [2.4mb PDF]
(Download full TONEAudio issue)

“For guts, fleshiness and wallop — the Isabella delivers more than class leaders at twice her price.”

Source: Srajan Ebaen,


Circuit Design
Included tubes 6922/E88CC dual triode (one tube per channel)
Accepted tubes 6922/E88CC, 6DJ8/ECC88, 7308/E188CC, 7DJ8/PCC88, 6N23, 6H23, and 6N11
Input impedance 50k
Output impedance Less than 1k
Frequency response 10Hz - 120kHz (+/- 0.5 dB)
Gain 0dB / 12dB (selectable)
Power supply transformer / rectifiers / transformers in signal path None
Battery Pack / Charger
Battery Red Wine Audio 25.6V LiFePO4 battery pack
Battery charger 30V, 2A LiFePO4 battery charger; Input voltage range: 100-240Vac, 50/60Hz
Typical continuous play time in battery mode between full charges Approximately 6 hours (with optional Isabellina DAC)
Approximately 8 hours (without Isabellina DAC)
Dimensions 12" width x 10.5" depth (including volume knob and rear panel jacks) x 3.5" height (including feet)
Weight (without charger) Approximately 10 lbs.
Package weight Approximately 16 lbs.