I25 Prisma Integrated Amplifier User Guide

Additional information

These instructions help you get the best possible sound from your I25.


The phase of the AC supply can make a significant difference to the sound.

Use the Polarity Pen supplied with the I25 to verify which pin is live on your AC power cable.

Ensure that the live pin of the AC power cable is connected to the left-hand pin of the power connector, viewed from the back panel:


Your Primare will start to sound best after an initial burn-in of approximately 24 hours. 

You will notice a further smaller improvement in sound quality for at least another 3 days’ playing.

RS232 and trigger

The RS232 input allows you to connect the I25 to a controller system. Use a twisted (null modem) cable. For more information contact Primare at info@primare.net or visit www.primare.net.

The Trigger output allows the I25 to switch on other devices, such as a DD35.

Using the I25 with a DD35

Your I25 is an ideal companion to the Primare DD35 CD Transport. For best results link the two products together as follows using the two cables supplied with the I25:

To connect the trigger cable

The Trigger cable ensures that the DD35 switches on, or to standby, when you operate the  button on the front panel of the I25.

  • Connect the Trigger cable from the I25 TRIG OUT to the DD35 TRIG IN.

Error message

The following error message on the front panel display indicates an error condition:


Clipping has occurred on an input. Decrease the input gain; see Input gain.

Factory reset

Press and hold the standby button on the front panel to display the main firmware version number.

Press and hold the standby button on the front panel for 10 seconds to perform a factory reset of the I25.

You can also do a factory reset from the Prisma app, or from the GENERAL SETTINGS menu; see General settings.

Network troubleshooting

Front panel display

The front panel display indicates the type of network connection:

LAN indicates that you are connected by an Ethernet cable.

WiFi indicates that you are connected by wireless. 

Network status

The CON indicator on the back panel indicates the network status:

ON Indicates the I25 is connected to a network

OFF Indicates no connection to a network

Flashing indicates that the network needs to be configured using the Google Home app.


A new feature found in the DM36 is the PCM up-sampling option, which when the setting is enabled in the Audio settings menu allows 16/44.1 and 24/48 kHz signals to be up-sampled to 24/88.2 kHz and 24/96 kHz respectively for improved internal digital conversion and digital output, noting that 24/96 kHz and 24/192 kHz files will not be up-sampled regardless of setting.


Additionally, the DM36 provides full MQA processing capabilities with both Prisma and Primare CD sources.

MQA (Master Quality Authenticated) is an award-winning British technology that delivers the sound of the original master recording. The master MQA file is fully authenticated and is small enough to stream or download.

This means that, with when playing TIDAL MQA files from the Prisma application, the Prisma models with the DM36 module installed will allow for the final MQA unfold to 384 kHz when playing Tidal Master files.  Noting that for all other Prisma models, including those using the DM35 DAC module, the update will allow for the first full MQA unfold to resolution up to 96 kHz, Qobuz resolution up to 192 kHz, and gapless playback for both platforms.

In Primare CD players and transports, MQA CD playback is supported with CD15 Prisma DD15, CD35 Prisma, and DD35 when using Toslink optical or RCA coaxial digital out connection to the DM36.

MQA indication in the DAC only versions of I25, I35 or PRE35 with DM36 the OLED display will show:

  • MQA – reflecting MQA
  • MQA. – reflecting MQA STUDIO

In the Prisma versions of I25, I35 and PRE35 the OLED will show as above as well as in the lower left of the Prisma app main page as below:

  • MQA GREEN DOT – reflecting MQA
  • MQA BLUE DOT – reflecting MQA STUDIO

‘MQA Studio’ (blue light) gives confirmation directly from mastering engineers, producers, or artists to their listeners, authenticating that the sound you are hearing is exactly as played in the studio when the music was completed and, by implication, that this is also the definitive version of the recording at that point in time.

‘MQA’ (green light) indicates that although the stream is a genuine MQA file, provenance may be uncertain or that it is not yet the final release.

Spotify Connect

The Spotify Software is subject to third party licenses found here: 



Printing or saving as PDF

You can print an on-line Primare user guide from your web browser, to provide you with a permanent copy to refer to away from your computer.

Alternatively, you can save a user guide as PDF files, to refer to when are you not connected to the internet.

To do so, simply choose Print, or Print followed by Save as PDF, from your browser’s File menu.

For the specific procedure for each of the most popular web browsers see How do I print or save a PDF copy of the on-user guides?.


You can use Google Translate to translate the contents of the Primare website. To do that, select the language you would like to translate into in the list below.

Please bear in mind, since the Google Translate is an automatically generated translation, we do not take any responsibility for errors in the text.