Versatile High-Performance Integrated Amp with AKM 32-Bit DAC
This version of Primare's I25 integrated amplifier combines the DM35 digital to analog conversion stage with the award winning I25 modular integrated amplifier platform. It features Primare's UFPD 2 amplification technology, delivering 100 watts of power per channel, with the option of adding the SM35 Prisma network player module at any time.
The I 25 Prisma is the latest iteration of Primare's now iconic integrated amplifiers and among the first to use the new UFPD 2 power system, a radical reworking of Primare's award-winning UFPD all-analog Class-D technology. Providing 100 watts at 8 ohms of absolutely linear UFPD 2 amplification across the entire audible bandwidth, I25 Prisma delivers naturally fast, clean and agile sound with an unprecedented ability to bring music to life.
In addition to five analog inputs, this version of the I25 includes the DM35 module, which is a full-featured DAC stage enabling up to PCM 768kHz/32bit and DSD 256 conversion.
On the input side, carefully crafted input circuitry utilizes relays for input switching providing better isolation and sound than found in more conventional CMOS (Complementary Metal Oxide Semiconductor) switches.
Modular Design Offers Versatility and Customization
This incredibly versatile and powerful integrated amp continues the Primare tradition of delivering astonishing performance from compact and elegant integrated amplifiers for easy installation into virtually any living environment.
The modular design of the I25 allows you to add the SM35 Prisma network player module to the amplifier at any time for unprecedented system customization.
The Amplifier Section
The amplifier section of the I25 utilizes the new proprietary UFPD 2 power technology, providing immediate and sustained high power output with very low distortion. It delivers instantaneous rise time and absolutely linear amplification across the entire bandwidth resulting in a naturally fast, clean and agile sound over an ultra-wide frequency range and with exceptional headroom.
In UFPD 2 a new error amplifier circuit has been developed that does not affect the gain versus frequency curve. Therefore, the bandwidth does not have to be limited. This gives very low phase shift in the audio band and a larger closed loop bandwidth.
Using a custom-made output coil in the second order filter error amplifier with the same loop gain provides feedback control across the entire audio band. It has been optimized to keep the loop gain constant in the audio band, which means it is actually lower at low frequencies than with UFPD, but much higher at high frequencies. The result is even more linear amplification, with lower noise thanks to UFPD 2, providing absolute "black" backgrounds from which music has a more holographic, three-dimensional, life-like character and richness.
The Power Supply Section
Given the speed with which the UFPD 2 amplifier module is able to deliver power to the speaker, a switch mode power supply was the only choice. It allows for rapidly varying demand, providing much more stable voltage, with ancillary capacitive storage to meet peak transient burst requirements.
This newly developed Active Power-Factor Correction (APFC) converter is as much as 5% more efficient than past supplies. It uses dual PFC converters 180 degrees out of phase from each other. AFPC is used to avoid input current harmonics, thereby minimizing interference with other devices being powered from the same source. This reduces the total current ripple and improves EMC (Electromotive Compatibility), while current ripple at the output of the PFC converter is also reduced, which decreases stress within the circuit for prolonged life.
Additionally, the supply operates in what is called "transition mode", minimizing switching losses and improving overall efficiency in delivering power to the UFPD 2 amplification module.
Advanced DAC Technology
In order to allow for playback of virtually any digital source with absolute accuracy and musicality, the I25's refined DAC stage recreates high-resolution sound that is as close as possible to the original source.
At the heart of this DAC stage is the new flagship of AKM's Verita series, the AK4497EQ chipset, a premium 32-bit stereo DAC, incorporating the companies VELVET SOUND technology, and capable of achieving -128dB (stereo) S/N and -116dB THD+N, while supporting up to 768kHz PCM and 22.4MHz DSD. This ability to handle higher resolution file formats will allow for the potential of future software upgrades.
The AK4497EQ 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. An innovative design technique utilizing a symmetrical layout for the left and right channels prevents signal quality deterioration, and a 32-bit digital operation block provides full 32-bit processing.
Inputs include four optical (Toslink), three RCA (SPDF), and one USB-B digital. The USB-B input allows playback of files up to PCM 768kHz/32bit and DSD256/11.2MHz.
One RCA digital output is included, allowing for pass through of digital signals and the option to select 48 or 96 digital output from analog sources.
Sleek Scandinavian Design
Every aspect of Primare products – the way they look, the satisfying feel of the controls – contributes to the overall experience. As a result, Primare products exude the hallmarks of Scandinavian design, featuring a simple, elegant look with approachable and easy-to-understand functionality.
An example of this is Primare's signature control knob, known throughout the industry for both its appearance as well as how it feels in the hand as an input is selected or volume adjusted. – or as they say in Swedish, lagom, meaning 'not too much not too little, everything in balance, proportion, and harmony.'
Modular Design and System Building
Primare feels it is essential to offer modularity whenever possible, in order to have just the right features, both now and for the future. Modular design is featured in the I25 and I35 modular integrated amplifiers, as well as the PRE35 modular preamplifier, all of which can be updated with DAC and Prisma modules, as well as the CD35 CD player that can have the Prisma module added, either at the time of purchase or at a later date.
As a result, Primare can offer a carefully considered array of models and configurations in order to allow for device selection that best fits any system need. For example, a CD35 with Prisma module installed can be paired with an I35 integrated amplifier, allowing for a separation of analog and digital stages. Or an I35 with DAC and Prisma modules installed can be paired with a DD35 CD transport, allowing for multi-room and multi-zone playback of every input, whether analog or digital source.
