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iFi Audio

iFi Audio Pro iESL Electrostatic Headphone Amp

The iFi Pro iESL Energizer is a "no holds barred" truly top of the line energizer that takes electrostatic headphones to a whole new level, with a variety of bias voltage options tailor made to drive everything from Koss, modern or legacy Stax headphones, and even the legendary Orpheus! Be sure to throughly read the Pro iESL User Manual for a comprehension overview of all features of this unique one of a kind Energizer!

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Truly Top of the Line

Imagine the audio equivalent of a Porsche engine of the flagship headphone world and you have the Pro iESL. Electrostatics need high voltages to energize them to make sound. The Pro iESL is one such energizer and delivers the extra-high-tension voltage needed. The capacitor pack has around 35,000,000 kOhm insulation resistance, which means that self-discharge time (to 30%) is around 100,000 seconds or 27 hours, making it one of the best energizers in the business. Iy's also compatible with all the great electrostatic brands – including Sennheiser Orpheus, Koss, Stax, Hifiman and more!

Just go Pro

The Pro iESL won’t disappoint. Coupled with a more traditional flagship amplifier, the Pro iCAN (or any other, but we like iFi Audio’s), the Pro iESL lowers distortion, separates vocals, orchestras and instruments. It opens up the bass and leaves you with a wide, structured soundstage. Through the use of custom wide band low noise transformers and a capacitive floating battery supply!

The Pro iESL can also be used with your flagship dynamic headphones thanks to a unique transformer-coupled-stage that can take them to the max.

Enjoy the pure luxurious, pleasure of flying high with your headphones – electrostatics or dynamics – with the iFi Pro iESL. No more background noise, no more distortion. Just smooth, sexy, open audio.

Forget the Porsche – just go Pro.

What's Included

• Electrostatic headphone energizer

• AC adapter with 5' DC output cord (DC output: 9V 2A)

• 9" ESL-Link cable (male HDMI plugs on each end)

• User Manual

• 12 month factory warranty

Input / Output

• "ESL-Link" input connector for use with iFi Pro iCAN headphone amp (cable included)

• Dual +/- speaker binding-post input

• Dual +/- speaker binding-post output

• 4 Pin XLR input

• 5-pin "pro bias" socket

• 6-pin "normal bias" socket for vintage electrostatic headphones

• XLR 4 Pin Balanced Headphone Out

The Specs

• Max Output Voltage: 640V RMS(20V in @ 16ohms) / 320V RMS (20V in @ 64ohms)

• Louder Speaker Input Parameters: Amplifier rating should not exceed 100W/8ohms

• Bias Voltage Settings: 230V(Normal), 500V(Custom for HE 90), 540V(Custom for HE-60,KS-H2/3/4), 580V(Pro), 600V(Custom for ESP 950/95X)

• Power Supply Connection: 5V-9V/1A DC power for stand alone operation without Pro iCan

• Frequency Response: 5 to 50kHz(-3dB)

• Power Consumption: <1W

• Dimensions 8.7"(W) x 8.4"(L) x 2.5"(H)

• Weight 5.5 lbs


About iFi Audio

iFi audio is an award winning audio tech company with one aim in mind – to improve your music enjoyment. They create products that improve sound quality and eradicate noise, distortion and hiss from your Headphones, Speakers, Portable audio devices and Phones allowing you hear studio-quality audio as your favorite artists intended.