This app note shows you how to stream audio over the network to a miniDSP 2x4 HD or DDRC-24 by using a Raspberry Pi Model 3A+.

If you're looking for an all-in-one streamer/DSP/digital preamp solution, check out our SHD Series streamers. In addition to the convenience of an all-in-one solution, these models have higher specifications, more digital inputs, digital outputs, and balanced analog I/O (for the SHD model).

Please note: miniDSP doesn't provide support for hardware and software that aren't miniDSP products. This application note demonstrates the use of miniDSP products together with other products.

What you'll need [Top]

For this app note we will be using the Raspberry Pi Model 3A+. This board is even smaller and cheaper than the popular Model 3B+, but has the same processing power. It has only one USB port and supports Wi-Fi only, no Ethernet. We thought it a good fit for this app note. You can use the Model 3B+ instead if you wish, as all the instructions are the same.*see footnote 1.

Raspberry Pi Model 3A+ on top of miniDSP 2x4 HD or DDRC-24

In addition to the Raspberry Pi 3A+, you will need a 5V power supply with micro-USB connector, a micro SD card, and a case. We used the official case as shown in the photos, but there are lots of choices. If you haven't used a Raspberry Pi before, you may prefer to buy a kit containing these extras together with the board.

You will of course need a miniDSP processor that accepts audio over USB. The miniDSP 2x4 HD and DDRC-24 are perfect candidates for a low-cost DSP-powered streamer, as they are compact and very affordable. These two units are the same hardware but the DDRC-24 has Dirac Live room correction built into it.

Before you proceed, we suggest that you start the 2x4 HD or DDRC-24 plugin (our word for their user interface/control program running on your computer) and make sure that you have selected USB audio input. You can also do this with an infrared remote later on.

Select USB input in the plugin

1. Burn the SD card[Top]

You'll need to download the software that will run on the Raspberry Pi. We'll use the Linux distribution called Volumio for this app note. This is the same base software that we use in our SHD Series streamers. Download it at https://volumio.org/get-started/.

Once you have it, burn it to the micro SD card. A good program for this is Etcher, which runs on Mac, Windows, and Linux. Insert the micro SD card into your computer's card slot or a USB card reader. Select the downloaded image and the card, and click "Flash!"

Warning: make absolutely sure that you have selected the SD card and that the size displayed in Etcher matches the size of your card.

Flash Volumio with Etcher

Take the card out of the slot or card reader and insert it into the Raspberry Pi. It goes in like this (looking at the bottom of the Raspberry Pi):

Insert SD card into the Raspberry Pi Model 3A+

2. Get connected [Top]

To connect the Raspberry Pi to your 2x4 HD or DDRC-24, just connect the USB cable from the Type A port on the Raspberry Pi to the mini Type B port on the miniDSP.

Connect miniDSP 2x4 HD or DDRC-24 to Raspberry Pi Model 3A+ by
USB cable

Now plug in the power to the Raspberry Pi and your miniDSP. You should see the red light on the Raspberry Pi come on and the green light start blinking. Wait a couple of minutes before proceeding to set up Wi-Fi.

3. Set up Wi-Fi [Top]

Use your computer's network manager to search for a wireless hotspot named Volumio. This is started automatically by Volumio when it can't connect to a network. Connect to this hotspot with the password volumio2:

Join the Volumio hotspot

Then open your web browser at http://volumio.local or http://volumio. Run through the startup procedure and select the miniDSP 2x4 HD or DDRC-24 on the third screen:

Select the miniDSP 2x4 HD or DDRC-24 in Volumio setup wizard

Navigate to the Network settings page and locate the Wireless Network Connection section. Select your home network and enter its password, then click Connect. We recommend that you connect Volumio to your home's 5 GHz network if you have one.

Join the home network

After Volumio connects to your home network, the interface will disconnect. Change your computer's network settings back to your home network and reload the Volumio interface. At this point, we recommend that you go back to Volumio's Network page and turn Off the Enable Hotspot setting, as leaving it enabled is a potential security risk.

4. Play music [Top]

For a quick start, go to Browse in the Volumio interface and select Web Radio, then Top 500. Take your pick and play!

Play Web radio to your miniDSP

Web Radio is not high resolution, but there are a lot of music playback capabilities in Volumio that are. Here are some ideas for you to explore:*see footnote 2

  • Go to the My Music page and enter your login details for TIDAL or Qobuz.
  • Look at the Plugins page to enable other services like Spotify and Pandora.
  • If you have a DLNA music server running on your network, locate it from Browse and then Music Servers.
  • If you have music files stored on a network share, add it on the My Music page. *see footnote 3
  • If you are an Apple user, select Volumio as the output device in System Preferences on your Mac or Control Center on an iOS device.

Wrapping up[Top]

That's it for this app note! Have fun, and please let us know how you go in our forum.

Footnotes

  1. If you use a Model 3B+ with Ethernet, you may experience some clicks or pops when streaming high-res audio. This is a consequence of the internal design of the Raspberry Pi and is unrelated to the fact that a miniDSP is connected to it. So even for the 3B+, our recommendation is that you use Wi-Fi. Note: no such Ethernet problems with our SHD Series streamers!

  2. Since the Model 3A+ has only one USB port, you won't be able to plug in a USB stick for music. As shown in the list, however, there are lots of other methods.

  3. If you have a large library on a network share, the Pi might slow down a lot when scanning it. For the sake of a number, consider a library of more than 10,000 tracks "large."


The miniDSP SHD includes not only Dirac Live® but also a full set of crossover functions on its four output channels. One use of this is as a flexible tool for integrating subwoofers into your system along with Dirac Live. This app note shows you how.

We will assume that you have already installed the SHD plugin and Dirac Live Calibration tool as per the User Manual. If this is your first time using a miniDSP for Dirac Live calibration, we recommend that you perform a calibration first using just the two speakers before attempting to integrate a subwoofer. This will familiarize you with the operation of the software. It will also give you a baseline that you can compare to the system with integrated subwoofer.

Getting connected[Top]

Connect the system as shown in this diagram:

SHD subwoofer integration - system connections

The diagram assumes that you are using one subwoofer. If you are using two subwoofers, connect the second to output 4.

Configuring the plugin[Top]

Start the SHD plugin and click the Connect button. (See the User Manual for more information.)

For clarity, use the Outputs tab to change the displayed labels on the output channels. In the example below, we have used "Left Sp", "Right Sp" and "Sub". Then set up the Routing matrix like this:

SHD subwoofer integration - routing matrix

If you are using two subs, turn on the routing from Dirac 1 and Dirac 2 to to output channel 4.

On the Outputs tab, click on the Xover button for channel 1. Here you will set a high pass filter, to remove low frequencies from the left speaker. Here is a typical example:

SHD subwoofer integration - high pass filter

Do the same for the right speaker (channel 2).

For the subwoofer (channel 3), set a low pass filter to remove high frequencies. Here is a typical example:

SHD subwoofer integration - low pass filter

If you are using two subs, do the same for the second sub connected to channel 4.

You can also set the time delay between the speakers and the sub using the output channels. As a starting point, use the difference in distance of the speakers and the sub to calculate the delay. For example, if the sub is 1 meter further away from the listening position than the speakers, set the delay on the speakers to 2.9 ms:

SHD subwoofer integration - delay on speakers

If the sub is 1 meter closer to the listening position than the speakers, set the delay on the sub to 2.9 ms:

SHD subwoofer integration - delay on sub

Note: subs in rooms are unpredictable. The above is just a starting point. You may need to make further adjustments after measuring (see next section).

Initial Measurement[Top]

We recommend that you perform a measurement to check for initial integration between the subwoofer and the main speakers around the crossover frequency. While Dirac Live will correct for frequency response anomalies, it can't fully correct if you have a large "hole" in the frequency response at the crossover.

You can use Room EQ Wizard (REW) or a similar program to do this measurement. To use REW with the UMIK-1, please refer to our application section on acoustic measurements.

If you don't wish to learn how to use REW, you can use the Dirac Live Calibration Tool to perform this measurement. Save your configuration to a file and quit the SHD plugin first. Then follow the normal calibration procedure described in the SHD User Manual, but only perform a single measurement (instead of the full set of nine) before proceeding to the Filter Design tab. The "before" measurement shows the combined response of the subwoofer and speakers:

SHD subwoofer integration - measurement with DLCT

If there is a large "hole" in the response around the crossover, you will need to make some adjustments and remeasure. Quit DLCT before starting the SHD plugin again. Adding a delay to either the speakers or the subwoofer will change the response, as will inverting the subwoofer. You can also adjust the low pass and high pass crossover frequencies and change the slope. If the subwoofer is much higher or lower in level than the speakers, adjust the gain on the subwoofer.

See the User Manual for information on how to make these adjustments. After making adjustments, quit the plugin, start DLCT, and repeat the measurement.

Run Your Dirac Live Calibration[Top]

You can now proceed to run the full set of nine measurements for the Dirac Live calibration. Adjust the target curve to suit your preference. For example, this screenshot shows a target curve with an elevated bass level, which many people prefer, and the "after" response:

SHD subwoofer integration - after optimization

Advanced multisub integration[Top]

For even better subwoofer integration, two or more subs can be used to reduce the variation in subwoofer frequency response across the listening area. While EQ can correct the response to be flat in one location in the room, it cannot correct for spatial variation. For example, if the level of 40 Hz in one seat is 10 dB different to the level in the next seat, the difference between the two seats will always be 10 dB.

We have an extensive app note on optimizing multiple subwoofer on our site here: Tuning multiple subwoofers with miniDSP.

  • If using two subwoofers, they can be connected directly to the miniDSP SHD (outputs 3 and 4).
  • If using more than two subwoofers, either:
    1. Use Y-connectors to connect two subwoofers to each output of the SHD. This will not give individual control over each sub but can be used to good effect with Methods A and B in the app note linked above.
    2. Use an external DSP such as a 2x4 HD or 2x4 Balanced. Up to four subwoofers can be independently controlled from each external DSP.

When optimizing your multisub setup, be sure to use a preset that does not have a Dirac Live calibration loaded, so that Dirac Live gains and delays are zeroed. When done with optimizing your multisub setup, then a complete Dirac Live calibration.

Wrapping up[Top]

That's it for this app note! Have fun, and please let us know how you go in our forum.

 


There are a number of well-regarded music players that can stream audio to the miniDSP SHD Series over your local area network (LAN). In this app note, we will show you how to use JRiver Media Center (JRMC). JRiver Media Center is available for Mac, Windows and Linux. It is a commercial program with a 30-day free trial.

We'll assume that you've already downloaded JRiver Media Center, installed it, and set it up with a library of music files on your hard drive. And, of course, that your SHD is connected to your network via its Ethernet port. Before proceeding, set the SHD to LAN input:

Select LAN input on miniDSP SHD

In order to stream audio to the miniDSP SHD, you will need to enable JRMC's Media Network functionality. In the sidebar on the left, click on Services & Plug-ins and then on Media Network. On the right, click on Options.

Enable media network for JRiver to miniDSP SHD

In the next dialog, check "Use Media Network to share this library and enable DLNA."

Enable DLNA for JRiver to miniDSP SHD

A new dialog box will open. Click Next twice and then OK. Choose "Audiophile 24-bit DAC (PS Audio etc.)" and then click Finish.

Configure media network for JRiver to miniDSP SHD

Now quit Media Center and start it again. The miniDSP SHD will appear in the left menu:

Default player for JRiver

Click on the miniDSP SHD to select it:

miniDSP SHD selected as player for JRiver

Then click on Audio, select an album, and play it. You should hear audio from the SHD! For extra bonus points, download JRemote onto your iOS or Android phone or tablet and set it up to remotely control audio playback from your computer:

JRemote screenshot from jremote.jriver.com

(Image from jremote.jriver.com)


The miniDSP SHD Series support a range of network streaming services, including Spotify, Tidal, and Qobuz. Even so, many of us still have a collection of music files that we want to play through an SHD Series processor. In a networked computer music system, a network attached storage (NAS) may be used for music file storage.

While there are many manufacturers of NAS units, in this app note we will use a Synology as an example, as they are a popular and widely-available brand. If you use a different brand of NAS, the general techniques in this app note should still work. However, you will need to figure out the specific settings for your brand of NAS.

To NAS or not to NAS? [Top]

What is a NAS? Essentially, it's a computer that is optimized for storage rather than running desktop apps. Compared to a typical desktop computer, it has a less powerful processor, no graphics capability, and much more storage. The software running on the NAS is typically a customized version of Linux that is optimized for managing hard drives and delivering files over the network.

NAS units often have multiple hard drives, 4 being a popular number for home and small office situations, and larger arrays of 8 up to 30 hard drives being used in enterprises. The drives are usually set up in a configuration called "RAID" (redundant array of inexpensive disks) to increase reliability. However, single and dual drive NAS units are also available.

Why use a NAS? Reasons vary. Perhaps you need a NAS for other reasons — video, surveillance, or backups, say — so storing your music files there is an obvious thing to do. Or, your music library has outgrown the storage that is in your computer. Or, you want to share the music files with everyone in the house. Or maybe you just want the files to always be available without having to have a computer switched on.

Do I have to use a NAS? No, not at all. It's an extra cost and complication, so if you're happy storing your music files on your computer, then that's fine. If you decide to add a NAS at a later time, you can come back to this app note then.

Preliminaries[Top]

We'll assume that you have already set up your NAS and figured out how to load music files onto it. When you set up a Synology, it creates a shared folder named "music" by default, so put some music files in there first. We'll also assume that you're able to log into the web-based user interface, DiskStation Manager (DSM).

In the rest of this app note, we'll present three methods of using a NAS with the miniDSP SHD. Pick the one that best fits your situation. In some cases, the size of the library determines which method works best, but this will be system dependent so you may need to experiment for yourself. We recommend picking one of the three methods and not mixing them up together.

Note: In our examples, the name of the NAS is "minidsp-NAS" and the username used to access it is "minidsp-user". You will need to substitute the NAS name and username that you used to set up your own NAS.

Method A: Mount the NAS from Volumio[Top]

In this method, Volumio is given the location of the NAS and fetches files directly from the NAS. You control playback using the Volumio web interface.

Use this method if you like to use the Volumio web interface and just want a simple way to access music files on the NAS.

Don't use this method if you have a large library.

Procedure:

  1. The recommended protocol for accessing files directly from Volumio is NFS. So turn on NFS sharing on your NAS and enable it for the music folder. For Synology, follow this tutorial: How to access files on Synology NAS within the local network (NFS). Here is how we configured the permissions page:

    Synology NFS settings to mount from miniDSP SHD
  2. In the Volumio web interface, go to the My Music page and click on "Add New Drive." The settings we used are shown here:

    Volumio settings to mount NAS

    Note that initially the group of settings at the bottom are not shown. You need to click on a button labeled "Show Advanced Settings" so that you can select nfs as the file share type. Leave the Username and Password fields blank.

  3. Click on Next and then OK. You will see the count of albums and tracks increase as Volumio scans the music files on the NAS:

    Files scanned on miniDSP SHD mounted NAS
  4. When scanning completes, go to the Browse pane. Clicking on the Music Library icon will enable you to browse by folder. However, clicking on Artists, Albums, or Genres will immediately show you the NAS contents in a friendlier style.

    Browse files on NAS from miniDSP SHD

Method B: Mount the NAS from your computer[Top]

In this method, you run a music player program on your computer. The music player program fetches audio files from the NAS and sends them to the SHD. You control playback using the user interface of the player program.

Use this method if you want to use a computer-based player like JRiver Media Center or Audirvana Plus.

Don't use this method if you don't want to have a computer turned on every time you play music.

Procedure:

  1. Install a suitable player app on your computer that can stream audio to the SHD Series. We have app notes here on our site for:

  2. If you haven't already, mount the NAS on your computer. In the case of Synology, there are tutorials on their website for:

    Note: While the tutorials linked above use the IP address of the NAS, we found that using the name of the NAS worked fine e.g. "minidsp-nas" or "minidsp-nas.local".

    On the Mac, the recommended file sharing protocol is AFP. If you are not using Synology, check that AFP is enabled on your NAS. If it cannot be enabled, try SMB, but we found in our tests that AFP was faster. Here is the screen to connect to the server:

    Mount Synology NAS on Mac

    (Enter "smb://minidsp-nas" if you cannot enable AFP on your NAS.)

    On Windows, you will need to first mount the NAS as a drive letter. We used "M", like this:

    Mount Synology NAS on Windows
  3. In the music player program, set the folder of the music library to the mounted NAS folder. For example, in Audirvana Plus on Mac it looks like this:

    Mount Synology NAS with Audirvana PLus

    In JRiver Media Center on Windows, it looks like this:

    Mount Synology NAS with JRiver
  4. Note: If you want to index local files as well as files on the NAS, both of these programs allow you to add additional folders to the library.

  5. The music player program will start indexing the music files on the NAS. This may take a while if the library is large.

Method C: Install a UPnP music server on the NAS[Top]

In this method, you install a music server directly onto your NAS. You control playback using a control app running on your computer, phone or tablet. For large libraries, this is generally more efficient than the above two methods, as the music server is running on the same processor that is attached to the hard drives.

Use this method if you have a large or very large library or if you have multiple people that will need to play music.

Don't use this method if you don't want to deal with installing and learning more bits of software.

Synology provides a UPnP server named Media Server for its NAS units, which serves music, photos and videos. However, we recommend that you install the third-party MinimServer instead, which is just as easy to install. MinimServer serves music only and is more optimized for that purpose. In our testing, we found that MinimServer scans a large music library much more quickly.

Note: if you have a different brand of NAS, you may still be able to install MinimServer. Check the list of supported NAS units on the MinimServer installation page.

Procedure:

  1. Open the web-based user interface of your Synology NAS. Open the Package Manager and search for "MinimServer". Click Install.

    Locate MinimServer package on Synology NAS
  2. Once installed, click on Open. You will need to agree to the terms of use and will then see a basic control page. Enter "/volume1/music" for the content directory (*) and click Update. Then click Rescan.

    MinimServer status page on Synology NAS

    (*) "/volume1/music" is the default folder set up by the Synology NAS for shared music storage. If you have configured your NAS differently, use the path to the folder that you have set up.

  3. Install a control app on your computer, phone or tablet. The specifics of each app are different, but generally speaking you will want to use the settings in the app to select "minimserver[minidsp-NAS]" as the music server and "minidsp-shd" as the player (also known as "renderer" or "room"). Here are some control apps you can try:

  4. To monitor the status of MinimServer, install the utility program MinimWatch. MinimWatch also allows you set multiple music directories and to configure more advanced features of MinimServer if you wish to do so. The instructions are at these links:

Note: you will find that you can browse MinimServer from within the Volumio web interface by clicking Browser and then Media Servers. However, this does not work as well as using a control app running on a computer, phone or tablet. To avoid confusion, we suggest that you go to the My Music page in the Volumio web interface and disable the option "DLNA Browser."

Disable DLNA browser in Volumio web interface

A note on JRiver Media Center[Top]

JRiver Media Center was used in Method B as a computer-based player for the library on your NAS. However, it can also be used as a control app for Method C by following these steps:

    1. Enable Media Network.

    2. Click on "Now Playing" in the left sidebar.

    3. Click on the library MinimServer[miniDSP-NAS].

    4. Click on the "Load Library" button on the right.

      Load MinimServer when using JRiver as controller

 

  • Click on Minidsp shd in the sidebar and select an album to play. The library and audio destination will be highlighted in green while playing:

 

Playing from MinimServer to miniDSP SHD with JRiver  as controller

There are a number of well-regarded music players that can stream audio to the miniDSP SHD Series over your local area network (LAN). In this app note, we will show you how to use Audirvana Plus. Audirvana Plus is available for Mac and Windows. It is a commercial program with a 15-day free trial.

We'll assume that you've already downloaded Audirvana Plus, installed it, and set it up with a library of music files on your hard drive. And, of course, that your SHD is connected to your network via its Ethernet port. Before proceeding, set the SHD to LAN input:

Select LAN input on miniDSP SHD

Open Preferences in Audirvana Plus and go to the Audio System tab. Click on the Change button next to the Preferred Audio Device option to drop down a selection menu:

Preferred Audio Device for Audirvana Plus to miniDSP SHD

Select UPnP: Minidsp shd and click the Select button. Set the other options as shown in this screenshot:

Preference pane for Audirvana Plus to miniDSP SHD

If the SHD isn't showing up as a choice in the Audirvana Plus Preferences, go to the Volumio web interface for the SHD and in the My Music settings, double-check that UPNP Renderer is enabled:

Enable UPnP for Audirvana Plus to miniDSP SHD

Now go to the Audirvana Plus Library pane, select an album from your library and play it. You should hear audio from the SHD! For extra bonus points, download the A+ Remote onto your iPhone or iPad and set it up to remotely control audio playback from your computer:

A+ Remote from Audirvana.com

(Image from audirvana.com)