STAX - SRM-400S

Electrostatic Energiser For STAX Headphones

Sale price₹ 89,999 Regular priceMRP: ₹ 118,990
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Your order leaves our warehouse within 24/48/72 hours - packed, handed to our courier, and on its way.

Orders placed before 2 PM on weekdays typically ship the same day.

This doesn't mean it arrives in 24/48/72 hours - delivery takes 3-4 working days depending on where you are.
Check the delivery date above for your estimate.

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Defective? Tell us within 7 days. We'll take care of it.

Something wrong with your product? We'll sort it out.

Wrong product, damaged, or missing parts: Let us know within 24 hours of delivery. If it's just an accessory, we'll replace the accessory.

What we'll need:

- Product in original packaging with all accessories

- Unboxing video and images of the parcel


This helps us see what went wrong and move faster.

Manufacturing defect: Let us know within 7 days of delivery. We'll replace or refund.

The process:
1. Raise a request - you'll get a RET number and hear from us by the next working day.
2. Once approved, we arrange pickup.
3. We inspect the product (2-3 working days).
4. Replacement shipped or store credit or refund issued.

A replacement or refund will be issued if:

- The product is found to be defective

- It wasn't damaged while in your possession-

- The same product is returned in original condition - box, MRP tag, manual, warranty card, all accessories



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1 Year warranty included. You're covered.

This STAX - SRM-400S comes with a 1 Year manufacturer's warranty from STAX, covering manufacturing defects.

Every product on Headphone Zone is backed by an original manufacturer's warranty.

Need support? Start with us. We handle most brands' warranty claims directly, and for the rest, we'll help you connect with the brand.

Read about STAX's Warranty
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Exquisitely Engineered SRM-400S New DC Amplifier With FET Installed In All Stages

STAX introduces a new semiconductor driver unit SRM-400S, the successor model of SRM-353X. The solid-state amplifier, SRM-400S, exhibits remarkable versatility and excellence. Your appreciation will grow as you progress with your listening session. STAX introduces a new semiconductor driver unit SRM-400S embedded with STAX custom-made low noise DUAL FET installed on First Stage with a FET also installed on Last Stage. The characteristics of right FET and left FET are measured strictly. SRM-400S is an amplifier with FET installed in all stages. In addition to the conventional power transformer for the high voltage circuit, the newly designed power transformer with the winding for the low voltage circuit is installed in SRM-400S. The low voltage winding improves the power efficiency and achieves further power saving and better sound quality than the conventional driver units. The complete DC amplifier configuration of the signal circuit includes no coupling condensers.

Experience Hi-Fidelity And Distortion Free Audio With The STAX SRM-400S

SRM-400S amplifies the analog signal from the input with as little fuss and distortion as possible. SRM-400S is a promising new model with a renewed driver unit lineup with each range well harmonised from the low to high. SRM-400S does justice across the frequency spectrum with greater precision. It is a rock-solid performer that deserves the attention of anyone who’s looking for an electrostatic headphone amplifier capable of driving high-end earspeakers. Its sound is undistorted, sparkly, and exciting. SRM-400S has an impressively wide soundstage delivering full-range sound.

Visual Glory With A Solid Built Chassis, Dual-Volume Knob Along With RCA & XLR Outputs

Experience full visual glory with the all-new chassis that is more rigid than the conventional models. The chassis has a hybrid structure using a lot of non-magnetic aluminium and further reduces the effect of the environmental noise factors such as vibrations. SRM-400S is embedded with a custom-made concentric dual volume knob and RCA parallel out functions. As for the aesthetics, you will find the understated elegance and simplicity of SRM-400S extremely attractive. The front and the back conform to the familiar STAX design architecture.

Impeccable Specifications Featuring Input-Output Capabilities

STAX SRM-400S is available in Black finish with a silver faceplate featuring improvements in the output stage, chassis design, power transformer, and overall performance. SRM-400S has a Frequency response of DC – 90kHz (with one SR-L500 MK2) and a Gain of 60dB with an Input impedance of 50kΩ. It has a maximum output voltage of 400v Rms (1kHz) with a Bias voltage of DC 580V and power consumption of 30W. SRM-400S comprises Input terminal RCA x 1, XLR x 1(mutual exclusion input), and an Output RCA parallel output terminal.

Experience Hi-Fidelity And Distortion Free Audio With The STAX SRM-400S

SRM-400S amplifies the analog signal from the input with as little fuss and distortion as possible. SRM-400S is a promising new model with a renewed driver unit lineup with each range well harmonised from the low to high. SRM-400S does justice across the frequency spectrum with greater precision. It is a rock-solid performer that deserves the attention of anyone who’s looking for an electrostatic headphone amplifier capable of driving high-end earspeakers. Its sound is undistorted, sparkly, and exciting. SRM-400S has an impressively wide soundstage delivering full-range sound.

Visual Glory With A Solid Built Chassis, Dual-Volume Knob Along With RCA & XLR Outputs

Experience full visual glory with the all-new chassis that is more rigid than the conventional models. The chassis has a hybrid structure using a lot of non-magnetic aluminium and further reduces the effect of the environmental noise factors such as vibrations. SRM-400S is embedded with a custom-made concentric dual volume knob and RCA parallel out functions. As for the aesthetics, you will find the understated elegance and simplicity of SRM-400S extremely attractive. The front and the back conform to the familiar STAX design architecture.

Impeccable Specifications Featuring Input-Output Capabilities

STAX SRM-400S is available in Black finish with a silver faceplate featuring improvements in the output stage, chassis design, power transformer, and overall performance. SRM-400S has a Frequency response of DC – 90kHz (with one SR-L500 MK2) and a Gain of 60dB with an Input impedance of 50kΩ. It has a maximum output voltage of 400v Rms (1kHz) with a Bias voltage of DC 580V and power consumption of 30W. SRM-400S comprises Input terminal RCA x 1, XLR x 1(mutual exclusion input), and an Output RCA parallel output terminal.

Volume Knob

STAX SRM-400S embeds a volume knob that allows you to adjust volume seamlessly.

RCA Output

STAX SRM-400S features RCA output to connect with various audiophile-grade devices.

Control Button

STAX SRM-400S equips a control button to control the device easily.

Accessories to Get you Started

1. Power Cable
2. RCA Cable
3. Warranty Card
4. User's Manual

All You Need To Know About The STAX SRM-400S

Type
All-Stage FET Configuration DC Amplification Driver Unit
Frequency Response
DC – 90kHz (With One SR-L500 MK2)
Gain
60db
Harmonic Distortion
0.01% Or Less (1khz/100vrms Output)
Input Impedance
50kΩ (RCA), 50kΩx 2 (XLR)
Maximum Output Voltage
400vrms (1khz)


1 Year Warranty

Don't sweat it, this STAX - SRM-400S comes with a 1 Year warranty from STAX that covers manufacturing defects. All products featured on Headphone Zone are backed by an original manufacturer's warranty.

Read more about STAX's warranty in India.

Japanese Electrostatic Pioneers From 1938

Stax, founded in 1938, is a Japanese company that makes high-end audio equipment. Twenty-two years later, in 1960, Stax released their first electrostatic earspeaker, the Stax SR-1. Over the following thirty-six years, Stax produced a variety of amplification, earspeaker, tonearm, CD player, DAC, phono cartridge and loudspeaker products.

Stax is best known for its electrostatic and electret headphones, which they call earspeakers. Electrostatic headphones work similarly to electrostatic loudspeakers but on a smaller scale. In 1995, fifty-seven years after the company’s foundation, it became insolvent. The company was revived in 1996 as the new STAX company. In December 2011, Chinese loudspeaker manufacturer Edifier announced the acquisition of 100% equity in Stax.

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Other Details


Generic Name Energiser
Importer Details Importers Name: Ferrari Video
Address: 63/18, 1st Main Road, Gandhi Nagar, Chennai - 600020
Contact No: 044-24420733
Dimensions 195 x 102 x 376 mm
Net Quantity 1
Manufacturer Details Name: Edifier International Limited
Address: Room 2101, 21st floor, The L. Plaza, 367-375 Queen's Road Central, Hong Kong
Package Contents STAX SRM-400S, Power Cable
RCA Cable
Warranty Card
User's Manual

Manuals & Guides



User Manual | SRM-400S

Electrostatic Energiser For STAX Headphones



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