STAX SRM-700T Vacuum Tube Driver Unit Review: Elevating Your Electrostatic Headphone Experience
Welcome to our STAX - SRM-700T Vacuum Tube Driver Unit Review, where we delve into the union of vacuum tube warmth and cutting-edge FET technology. If you’re chasing a truly immersive electrostatic headphone experience, the SRM-700T is engineered to deliver just that.
Design & Build Quality
At 240W × 103H × 393D mm and weighing 5.7kg, the SRM-700T strikes a fine balance between substantial presence and desktop compatibility. Its satin-black chassis is accented by the glowing 6SN7 vacuum tubes, housed under a minimalist protective cage. The front panel features a precision volume knob, elegantly engraved to provide just the right tactile feedback, while the rear offers RCA and balanced XLR inputs alongside parallel RCA outputs for flexible system integration.
Front, side and rear view of the SRM-700T
Sound Signature & Performance
The SRM-700T marries a low-noise dual FET first stage with the iconic 6SN7 GT tube in the second stage, delivering a sound that is at once warm, spacious and exceptionally detailed. Bass feels tight and well-defined, midrange textures are rich and three-dimensional, and treble is articulate without ever sounding etched. The hybrid design ensures a high slew rate, preserving microdynamics and transients—even on flagship electrostatic headphones like the STAX SR-009S.
Technical Deep Dive
Input Stage: Custom low-noise dual FET for ultra-clean amplification and stellar S/N ratio.
Tube Stage: Classic 6SN7 GT delivering that coveted vacuum tube tonality with simple, powerful performance.
Load Resistors: Non-inductive VISHAY winding resistors for stable, noise-free operation.
Frequency Response: DC–100kHz (with SR-009S), ensuring full-range reproduction well beyond human hearing.
Gain & Output: 60dB gain with up to 340Vrms maximum output—ample headroom for demanding electrostatic loads.
Distortion: ≤0.01% THD at 1kHz/100Vrms, revealing the purest signal path.
Who Should Consider the SRM-700T?
If you own—or aspire to own—electrostatic headphones and crave the soul-stirring warmth of tubes, the SRM-700T is your next step. It pairs beautifully with STAX SR-007 MK2, SR-009S and other high-end planar electrostatics. Studio engineers seeking a transparent yet musically engaging monitoring solution will also appreciate its neutrality and low noise. For those building a reference desktop or living-room setup, the SRM-700T brings a unique sonic signature that elevates every genre.
Pros & Cons
Pros
Rich, warm tonality from the 6SN7 tube stage.
Exceptional transient speed and detail from the dual FET input.
Wide DC–100kHz bandwidth for faithful reproduction.
Generous 60dB gain and 340Vrms output for demanding electrostatics.
Cons
Premium investment reflects its high-end pedigree.
Needs adequate ventilation to maintain optimal tube life.
Ready to Elevate Your Listening?
If you’re intrigued by how the STAX - SRM-700T Vacuum Tube Driver Unit can transform your headphone rig, speak with our expert team at The Audio Tailor. Call us on 1300 308 711 or email sales@theaudiotailor.com.au. Discover more details on our STAX SRM-700T product page and embark on the ultimate listening journey today.
