Stax
STAX SRM-700T Amplifier and SR-009S Earspeakers System
Best electrostatic system for audiophiles seeking rich, tube-infused sonic detail.
Experience unparalleled audio fidelity with the Stax SRM-700T amplifier, a hybrid electrostatic headphone driver inspired by flagship designs. It masterfully blends FET input stages with a warm 6SN7 vacuum tube output for rich, spacious sound reproduction. Featuring custom low-noise FETs and high-definition film capacitors, this amplifier ensures pristine signal quality. Versatile connectivity is offered through switchable RCA and XLR inputs, making it a sophisticated choice for discerning audiophiles seeking a refined listening experience.
$3400.00
Owner Satisfaction
4.8
/ 5
Category Rank
1
/ 732
Best Headphone Amplifiers
Price vs Category Average
+143%
Above average
Type
FET input + vacuum tube output hybrid DC amplification driver unit
/ FET input + vacuum tube output hybrid DC amplification driver unit
Who it's for
- Audiophiles seeking absolute clarity and microscopic musical detail
- Listeners craving a spacious, holographic, and immersive soundstage
- Purists wanting analytical precision balanced with natural tube warmth
Who should skip it
- Commuters or office workers needing noise isolation and privacy
- Budget-conscious buyers prioritizing value over luxury performance
- Users wanting compatibility with standard headphone amplifiers
Performance breakdown
Sonic Transparency
Electrostatic precision delivers unmatched detail and transient speed across the spectrum.
Harmonic Warmth
The 6SN7 vacuum tube stage adds a lush, organic character throughout.
Signal Integrity
Custom low-noise FETs ensure a pristine, black background for your music.
Build Quality
Robust chassis construction reflects the premium nature of flagship audio gear.
Connectivity Versatility
Switchable RCA and XLR inputs accommodate a wide range of sources.
Dynamic Range
High voltage output provides effortless headroom for complex musical passages.
Key Specs
Type
FET input + vacuum tube output hybrid DC amplification driver unit
Vacuum tube
6SN7 x2
Frequency response
DC – 100kHz (with one SR-009S)
Gain
60dB
Harmonic distortion
0.01% or less (1kHz/100Vrms output)
Input impedance
50kΩ (RCA), 50kΩx 2 (XLR)
Maximum output voltage
340Vrms (1kHz)
Weight
5.7kg
Features
- Hybrid amplification for rich, warm sound
- Vacuum tube output stage for spacious audio
- Custom low-noise FET input stage
- High-definition film capacitors for clarity
- EMI shielded volume control
- Switchable RCA and XLR inputs
- PRO 580V Bias voltage compatibility
- Desktop form factor
What customers say
The Stax system is widely celebrated for its superior sonic quality, setting a new high fidelity benchmark. Users consistently highlight the breathtaking transparency and microdetail when pairing the SR 009S earspeakers with the SRM 700T amplifier. This combination produces a truly lifelike audio presentation that dedicated audiophiles feel validates the premium investment. Moreover, the meticulous craftsmanship and elegant design firmly establish this pairing as a reference standard for serious listening experiences.
Know before you buy
The SRM-700T combines a custom low-noise FET input stage with a 6SN7 vacuum tube output stage. This design aims to provide the precision and low-noise floor of solid-state electronics with the warm, spacious harmonic character associated with tubes.
The SRM-700T is designed for Stax electrostatic earspeakers that require the standard PRO 580V bias voltage. It is specifically optimized for high-performance models like the SR-009S, but it will function with any Stax model utilizing the 5-pin PRO bias interface.
Yes, the unit features both RCA and XLR inputs. You can connect two separate sources and switch between them using the input selector on the front panel.
While solid-state drivers are often praised for their clinical speed and neutrality, the SRM-700T’s vacuum tube output stage introduces a subtle richness and depth to the soundstage. It is intended for listeners who prefer a more organic, textured presentation over a strictly analytical one.
Like any tube-based equipment, the 6SN7 tubes will eventually reach the end of their service life and require replacement. However, the unit is built for standard desktop use, and no specialized technical maintenance is required beyond ensuring proper ventilation for the chassis.
The EMI shielding protects the sensitive volume control circuitry from electromagnetic interference generated by other electronic devices in your home. This ensures that your audio signal remains clean and free from background noise or hum.
Still have a question?
Ask Hayley anything about this product before you decide.