Woo Audio
Woo Audio WA7e Fireflies
Best electrostatic amplifier for audiophiles seeking customizable tube sound.
The Woo Audio WA7e Fireflies is an electrostatic headphone amplifier and DAC designed for modern electrostatic headphones. It features a fully-balanced amplifier, user-replaceable 12AU7 vacuum tubes for customizable sound, and an ESS SABRE DAC supporting up to 24-bit/384kHz PCM and DSD256. This compact amplifier offers a tube preamplifier function, allowing integration with home speaker systems or powered desktop speakers. Its elegant design, assembled in New York, USA, complements its high-fidelity audio performance, making it a sophisticated addition to any audio setup.
$1399.00
More WA7 Fireflies Options
Owner Satisfaction
4.5
/ 5
Category Rank
410
/ 807
#410 in Headphone Amplifiers
Price vs Category Average
+0%
Below average
Who it's for
- Audiophiles seeking a rich, detailed, and immersive listening experience
- Design-conscious listeners wanting a beautiful, compact centerpiece for their desk
- Minimalists looking to consolidate their DAC, amp, and preamp setup
Who should skip it
- Budget-conscious buyers looking for entry-level audio equipment
- Listeners preferring a low-maintenance, set-and-forget audio solution
- Owners of power-hungry, low-impedance planar magnetic headphones
Performance breakdown
Electrostatic Drive Power
Delivers the high-voltage precision required for top-tier electrostatic headphone performance.
Sonic Customization
User-replaceable vacuum tubes allow for effortless fine-tuning of your audio signature.
DAC Resolution
ESS SABRE chipset handles high-resolution files with exceptional clarity and detail.
Build Integrity
Robust anodized aluminum chassis reflects premium American craftsmanship and lasting durability.
System Versatility
Integrated tube preamplifier functionality bridges the gap between headphones and speakers.
Connectivity Range
Broad compatibility across mobile and desktop platforms ensures seamless digital integration.
Key Specs
Requires 580v Electrostatic headphones
Compatible with electrostatic headphones from Audeze, STAX, HiFiMan, Dan Clark Audio and others
Compatible with Apple iPhone/iPad, Android devices, Mac and Windows computers
Tubes
12AU7 / 5963 driver tubes, self-biasing
Premium Polytetrafluoroethylene (PTFE) tube sockets
ESS SABRE Audiophile DAC up to 24-bit/384kHz PCM, and up to DSD256 (11.2MHz)
XMOS xCORE-AUDIO asynchronous USB compatible with PC, Mac, Android and iOS devices (with Apple CCK or Android OTG adapter)
High-retention USB connector x 1
Features
- Designed for modern electrostatic headphones
- User-replaceable 12AU7 vacuum tubes for sound customization
- ESS SABRE DAC for high-resolution audio playback
- Tube preamplifier functionality for system integration
- Compact and elegant design
- Assembled in New York, USA
- Includes essential cables and tubes
What customers say
Customers consistently praise the Woo Audio WA7e Fireflies for its exceptional sound quality and exquisite design. Many highlight its ability to deliver a warm, detailed, and engaging audio experience, transforming their listening sessions. The amplifier's compact, elegant aesthetic and premium build materials also receive widespread acclaim, making it a standout piece for any desktop. While a significant investment, users often feel its sonic performance and craftsmanship justify the cost, positioning it as a top tier choice for discerning audiophiles seeking both auditory bliss and visual appeal.
Know before you buy
No, the WA7e is specifically designed for electrostatic headphones that require a 580v bias. It is compatible with models from brands like STAX, Audeze, HiFiMan, and Dan Clark Audio, but it will not work with standard dynamic or planar magnetic headphones.
Yes, the unit features a tube preamplifier function with both 4.4mm balanced and 3.5mm stereo pre-out options. This allows you to connect it to powered desktop speakers or an external power amplifier for your home audio setup.
The WA7e uses 12AU7 vacuum tubes, which are known for adding warmth, texture, and a sense of space to the audio. Because the tubes are user-replaceable, you can experiment with different brands or types of 12AU7/5963 tubes to fine-tune the sound to your personal preference.
The XMOS-based USB input allows for plug-and-play connectivity with Mac and Windows computers, as well as Android and iOS devices. For mobile devices, you will simply need an Apple Camera Connection Kit or an Android OTG adapter.
The amplifier is self-biasing, which simplifies tube maintenance significantly. While the tubes will eventually need to be replaced after extended use, the process is straightforward and allows you to customize the sound profile of the amplifier.
The WA7e features an internal linear power supply that supports AC voltages between 115v and 230v. If your local power grid provides less than 115v, you will need to use a step-up transformer to ensure proper operation.
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$1399