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iFi Audio Pro iESL Headphone Amplifier and Energiser


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Enquiry/price check? Click here SKU: IFIPROIESL
Ex VAT: £1,245.83
Pro iESL, ideal with iFi Pro iCan, is a flagship headphone amp and superior energiser opening up the bass to reveal a wide, structured soundstage.

Available - Ships within 2-3 days

Condition: Brand new in original retail packaging

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Warranty length 2 Years
Brand iFi Audio

Tech Specs

- Max Out: 640/320V RMS (16/64Ω) 20V
- Freq Response: 5Hz – 50kHz (-3dB)
- Input Voltage: 5V – 9V/1A max
- Power Consumption: < 1W
- Dimensions (LWH): 213 x 206 x 63.3mm
- Weight: 2.5kg (5.5 lbs)

Product Description

iFi Audio Pro iESL Headphone Amplifier and Energiser can be coupled with traditional flagship amplifiers, like the iFi Pro iCan, to lower distortion as well as separates vocals and instruments.

Pro iESL Capacitor

Electrostatics need high voltages to energise them to make sound. The Pro iESL capacitor pack has around 35m kOhm insulation resistance, which means that self-discharge time (to 30%) is around 100,000 seconds or 27 hours. This makes it one of the best energisers in the business and compatible with all the great electrostatic brands.

Just go Pro

Pro iESL can also be used with flagship dynamic headphones thanks to a unique transformer-coupled stage that can take them to the max. Enjoy the pure luxurious experience of flying high with your headphones whether they are electrostatics or dynamics. No more background noise, no more distortion.

Perfectly Matched

Both classic and cutting edge technology in the one-off Pinstripe Permalloy Core Transformer, Bias Voltage Generator and the Capacitive Battery Power Supply deliver a perfectly matched listening experience.

Wide Bandwidth

To acheive the wide bandwidth and low distortion needed in the iESL, the custom transformers use complicated hand-wound, multi-section windings with both vertical and horizontal sectioning. With a bandwidth of <5Hz to >60kHz (-3dB), transformers in the iESL far exceed the standards set by Siemens and Peerless and the requirements of the JAS.

Capacitive battery supply

The battery is charged up to the required voltage and then the charger circuit is turned off completely, leaving the capacitor bank to ‘float’ at the required bias voltage. An essentially perfect bias voltage source with no electronic noise whatsoever at any frequency as the headphones are powered by the battery bank and not the mains. These German-made 1000V rated capacitors deliver very high insulation resistance and minimal current leakage, as any such leakage causes self-discharge.

Vishay MELF resistors

These metal electrode leadless face resistors have excellent accuracy, stability and reliability. They provide optimal power rating and pulse load capability.

For flagship dynamic headphones

The iESL has an ear-tingling transformer coupled-stage that is not found in other energisers. Each and every flagship dynamic headphone, when used through the iESL, enjoys a whole new level of smoothness and airiness.

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Contact Details

UK Local Rate Number
0844 50 403 50

Sales Landline
0121 224 7300/7401

Customer Services Landline
0121 224 7350/7351

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