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STAX - SRM-400S - Drive Unit
STAX - SRM-400S - Drive Unit
STAX - SRM-400S - Drive Unit
STAX - SRM-400S - Drive Unit

STAX

STAX - SRM-400S - Drive Unit

$2,500.00

In stock

Delivery Australia-wide

Shipping calculated at checkout

Pick up from The Audio Tailor Usually ready in 2-4 days. We'll let you know when it's ready to collect. Store info
9/20 Rivergate Pl, Murarrie QLD 4172
Tuesday to Friday
9am to 5pm
Saturday
9am to 3pm
Sunday and Monday
Closed
Get directions Call 1300 308 711 Book a listen

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Unit 9/20 Rivergate Place, Murarrie, Qld 4172 Get directions
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Overview

SRM-400S

Brand
STAX
Category
Headphone Amplifiers
SKU
SE-SRM400s

Not sure it's the right fit for your room or system? Our team can talk you through it.

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Our thoughts

Matched FETs in both the first and last stages carry the SRM-700S approach down to a driver built for owners stepping up from entry-level STAX gear. It is aimed at committed listeners who want all-FET, DC-coupled circuitry without the top-of-range commitment.

First and last stage FETs are measured and selected per channel, aiming for closely tracking left and right circuits. A new power transformer with a low-voltage winding is designed to improve efficiency. The rigid hybrid chassis uses non-magnetic aluminium to reduce vibration, so the circuitry is less exposed to interference. With no coupling capacitors, the signal path is intended to stay direct from input to output. Mutually exclusive RCA and XLR inputs let you choose one active input.

It suits lambda series owners and SRS-3100 upgraders, with a concentric dual volume knob shared across STAX units. Call the team, or talk it through with us in the showroom, about headphone matching or your source and input choice.

The Audio Tailor team, Murarrie showroom

STAX introduces a new semiconductor driver unit SRM-400S headphone amplifier, the successor model of the SRM-353X. STAX custom-made low noise DUAL FET is installed on First Stage. And FET is also installed on Last Stage. The characteristics of right FET and left FET are measured strictly. Selected FET are installed as well as SRM-700S. SRM-400S succeeds to the design and the manufacturing method of the high end model SRM-700S, the amplifier which FET are 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 enables to improve the power efficiency and achieve further power saving and better sound quality than the conventional driver units such as SRM-353X.

The new chassis which is more rigid than the conventional model is installed. The chassis has a hybrid structure using a lot of non-magnetic aluminum and further reduces the effect of the environmental noise factors such as vibrations. The inputs are RCA and XLR, the mutual exclusion inputs. The custom made concentric dual volume knob which is common to STAX products and RCA PARALLEL OUT functions are installed same as the conventional driver units. All electric components are strictly selected considering the environment. Also the sound quality and the performance is improved. The complete DC amplifier configuration that the signal circuit includes no coupling condensers is one of the biggest traditional features.

SRM-400S takes over the high resolution sound which is unique to the semiconductor circuit and dynamic low range sound reproduction. Simultaneously, the good sound balance is further pursued than SRM-353X. From the low range to the high range, the sound of each range is well harmonised. Not only for the combination with the advanced lambda series, SRM-400S is also ideal for the upgrading from the entry level SRS-3100. This is the promising new model which covers from beginners to intermediates among the renewed driver unit lineup.

Specifications

Technical details

Manufacturer specifications. Want to know how it compares with something else? Ask our team.

All-stage FET configuration DC amplification driver unit
Frequency responseDC - 90kHz (with one SR-L500 MK2)
Gain60dB
Harmonic distortion0.01% or less (1kHz/100Vrms output)
Input impedance50k Ω (RCA), 50k Ω x 2 (XLR)
Maximum output voltage400Vrms (1kHz)
Bias voltageDC 580V
Operating temperature / humidity0 to 35 degrees celsius / less than 90% (non condensing)
Input terminalRCA x 1, XLR x 1(mutual exclusion input)
OutputRCA parallel output terminal
Power consumption30W
Weight3.4kg

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Saturday
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