Primare I35 Prisma Integrated Amplifier

New Blood

Equipment report
Integrated amplifiers
Primare I35 Prisma Integrated Amplifier

The Swedish-built I35 Prisma integrated amplifier, the latest model in Primare’s highly regarded 30 Series, exemplifies a new breed of integrated amp. Where once upon a time the integrated existed in a world apart from separates, and then only as a humble, low-cost, space-saving component, the last few years have seen a rise in high-powered, full-featured, upmarket contenders brimming with connectivity and outfitted with premium internals. Much of this uptick can be credited to the introduction of high-resolution onboard DACs. But streaming services and storage options have also elevated the integrated amp to even greater heights as a complete one-box solution. So much so, that many enthusiasts might start asking, “Separates? Who needs ’em?” It’s a question that kept occurring to me as I’ve evaluated the new generation of integrateds.

Outwardly, the I35 is pure Primare, a pristine appearance that has remained unsullied over the years. The thick, brushed-aluminum faceplate sports a wide rectangular OLED display and a quartet of small buttons that include power, menu, and configuration. The display is flanked on the left and right by pleasingly tactile selector and volume knobs. 

In spite of the front panel’s minimalism, the I35 is teeming with connectivity: Wi-Fi and Ethernet for network-based storage, Bluetooth, AirPlay (for Apple devices), Spotify Connect, and more. Perhaps most importantly, the I35 is equipped with Chromecast (a streaming portal à la Apple TV) that when connected via a Wi-Fi network (or Ethernet) can “cast” a galaxy of music-streaming services to the Prisma and, when operated from the Google Home app (a free download), will connect with a panoply of Google home/multi-room devices. (For Old School users dedicated to conventional sources, such as CD players, the I35 is available in an analog-only version sans DAC and network connectivity.)

The relatively crowded real estate of the back panel speaks to the wide-ranging inputs that the I35 offers. The top row of digital inputs includes four optical, a pair of coaxial plus USB-B for a computer (PC or Mac), and a coaxial digital output. Sturdy footers isolate the chassis from vibration. Network LAN connections and a USB-A slot reside between the dual antenna taps. The bottom row is dedicated to analog inputs, including a pair of balanced XLR and three unbalanced RCA, a pre-out, and a line-level out. The speaker terminals are on the lower left beside the IEC plug and on/off rocker switch. Irksome, however, is the placement of the speaker terminals which are positioned so low on the panel that it is difficult to affix commonly used spade connectors and larger cables. Prospective owners might consider banana plugs instead.

The I35’s Class D output stage delivers 150Wpc into 8 ohms, and 300Wpc into 4 ohms. The interior layout uses space efficiently by virtue of two- and four-layer double-sided circuit boards for shorter signal paths. Surface-mount components are also used whenever possible, again to keep signal paths short. 

The amp section of the I35 is the first to use Primare’s proprietary UFPD 2 power-module technology, powered by a switching power supply. Primare’s literature states that the new circuit improves on earlier generations with “immediate and sustained high power output with very low distortion, lower noise and extended headroom, instantaneous rise time, and absolutely linear amplification across the entire bandwidth… over an ultra-wide frequency range.”

My review sample included the DAC stage—an AKM AK4497EQ 32-bit stereo DAC capable of supporting up to 768kHz PCM and 22.4MHz DSD. Noteworthy is that this DAC “integrates a newly developed switched-capacitor filter ‘OSR Doubler’ that greatly reduces sound degradation from noise shaping, achieving a flat noise floor up to 200kHz.” Further, the USB-B input allows playback of files up to PCM 768kHz/32-bit and DSD256/11.2MHz.