ONKYO A-9150

Onkyo A-9150 Integrated Stereo Amplifier (Open Box)

An open box Onkyo A-9150. Please note that no factory warranty applies. The A-9150 is a meaningful step up from the A-9110, adding a built-in DAC, a dedicated MM/MC phono circuit board, and Onkyo's proprietary Discrete SpectraModule to a power amplifier section that is already significantly refined over the entry-level models in the lineup. The Class AB amplifier delivers 30 watts per channel into 8 ohms and 60 watts into 4 ohms, powered by a customized high-output transformer and two large custom audio-grade capacitors feeding discrete output-stage transistors cooled by an aluminum heat sink — providing the high current delivery needed for confident, authoritative speaker control across dynamic and complex musical passages.

The Discrete SpectraModule is the standout engineering achievement of the A-9150, boasting a slew rate of over 500V/µs — far exceeding what standard IC chip-based circuits achieve — enabling flat linearity well into the megahertz range for full-bandwidth signal reproduction and a larger, more precisely defined soundstage. Digital sources are handled by an AKM 768kHz/32-bit DAC with Onkyo's DIDRC (Dynamic Intermodulation Distortion Reduction Circuitry) filter, which eliminates ultra-high-frequency noise introduced during D/A conversion before it can be amplified. Two optical and two coaxial digital inputs support PCM up to 24-bit/192kHz. The dedicated MM/MC phono circuit board features its own separate equalization stages served by a customized discrete head amplifier for MC signals, preserving the full depth and vitality of vinyl playback. Four gold-plated RCA line inputs, A/B speaker switching with gold-plated binding posts, a front-panel headphone output, Direct mode, and a remote control complete the package.