Ask S&V

Q I own an NAD T 787 A/V receiver that only supports regular HD video pass-through and Dolby True HD/DTS-HD Master Audio processing. This receiver features NAD’s MDC (Modular Design Construction) for hardware upgrades. NAD offers an audio module with Dolby Atmos support, along with outputs for two sets of height speakers. If I stick with my current 5.1 speaker setup, would the Atmos module upgrade improve sound quality? Or will my receiver simply downmix the Atmos soundtracks to 5.1/7.1 surround with no audible improvement? —Phil Tomaskovic, via email

Q I read your response to a reader who asked about using dipolar speakers as surrounds in an Atmos system. You recommended “losing any side-mounted dipole surround speakers in the system and replacing them with properly positioned direct-radiating models.” Does that same advice hold for bipolar surrounds? —Darryl Brooks, via email

Q I have tried streaming Amazon Music HD to my Marantz SR7015 receiver over Bluetooth from my iPad using the receiver’s HEOS app. The app shows resolutions all the way up to 24 bit/192kHz — something I didn’t think was possible with Bluetooth! Will I get the same resolutions if I make a hardwired connection from iPad to AVR using an AudioQuest DragonFly Red USB DAC? —Paul Giovino, via email

Q I own a Marantz SR6013 A/V receiver and use it for both video switching and audio amplification. For video, I mostly watch Ultra HD Blu-ray discs. For music, I mostly stream from the Tidal service using the Marantz receiver’s built-in HEOS app. I would like to buy an external digital-to-analog converter (DAC) that supports MQA but am confused about the connections and the control app. After checking out my Marantz AVR’s back panel, I see two coaxial and optical digital inputs, but no digital outputs to connect the DAC, so maybe using an external DAC with the AVR is not possible. Am I missing something? —Rod McClaskey, via email

Q What’s the best way to connect a subwoofer used mainly for music listening? I’ve been trying both the stereo RCA and mono LFE input connections on my Klipsch R 120SW subwoofer, but am not sure which works best, and also where I should set the low-pass/LFE filter on my Onkyo TX-NR717 receiver. My front speakers are Klipsch R-28F towers. I would appreciate any recommendations on crossover settings for the receiver and the subwoofer itself. —Ken Zarubi, via email

Q Do the preamp outputs on A/V receivers work as well as those on a standalone preamp-processor? What functionality does one lose when using pre-outs on a receiver? —Ravinder Dhawan, Watchung, NJ