Introducing DSPi | A powerful, user friendly and open source DSP for less than a cup of coffee

[Weeb Labs]

Would it add a lot of complexity to allow the code to also run on a more powerful rPi model?

I'm afraid that would not be possible. This is firmware that runs on the Raspberry Pi Pico (RP2040/RP2350) microcontrollers. It is not software that runs on top of an operating system, as one would find on an SoC Raspberry Pi such as the 4 or 5.

 

[john61ct]

Aha that's a new distinction for me, thanks for that

 

[Weeb Labs]

Today's release is now available! This release focuses on stability and optimization but there are a couple of rather important new features.

Here is the complete list:

• System performance optimized (DCP logic) to increase performance by 12%
• USB descriptor bug fixed - Windows now automatically installs all necessary drivers when DSPi is connected
• All output pins can now be changed at any time while the device is running
• New CPU load monitoring system with far greater accuracy - Below 100%, audio will always be stable
• The firmware now reports its version, the device platform (RP2040/RP2350) and its unique serial number to the host
• Crossfeed window is now resizeable in DSPi Console for macOS
• Filter response graph no longer displays curves for disabled channels upon launch
• Import/Export Filters now includes filters for all enabled channels

Known bugs/limitations:

• DSPi Console & Firmware: Channel peak meters are only available for USB In, SPDIF 1 and PDM. Some UI redesign needed in order to accommodate.
• DSPi Console: Filter response graph is updated every 60ms. Need to cache.
• DSPi Console: Visually similar response curves are not treated as one for gradient display purposes.

Links:

• DSPi Firmware v1.0.9
• DSPi Console v1.0.9 for macOS

The Windows version of DSPi Console will be receiving a feature parity update very soon.

 

[kazuviking]

Wow, nice work. Is it possible to have all four spdif outputs with L and R separate in "dual" mono(both downstream device sees the specific channel duplicated, yes i know rca splitters exists), center channel with band pass eq and sub out active? Its such a niche that i don't know if it exists. This project came in clutch as i couldn't find a non astronomically priced DSP for my silly experiments.

 

[Weeb Labs]

Wow, nice work. Is it possible to have all four spdif outputs with L and R separate in "dual" mono(both downstream device sees the specific channel duplicated, yes i know rca splitters exists), center channel with band pass eq and sub out active? Its such a niche that i don't know if it exists. This project came in clutch as i couldn't find a non astronomically priced DSP for my silly experiments.

Thank you!

Absolutely. You can route any channel(s) to any channel(s) via the Matrix Mixer in the Tools menu.

 

[mike_008]

Hello,
great project! Would it be technically possible to capture i2s inputs (ideally 8 inputs = 16 audio channels) and output them together as USB class audio with pico hw?

Just realized Pico only supports USB 1.1 by its HW.
So question would be: How many audio channels could be transferred in and out over USB 1.1 simultaneously?

 

[Weeb Labs]

Just realized Pico only supports USB 1.1 by its HW.
So question would be: How many audio channels could be transferred in and out over USB 1.1 simultaneously?

Eight channels are the practical limit, so that would be four bidirectional channels

 

[kwas]

Excellent project worthy of support! One question, would this be recognized in Picore player as a USB audio device?

Thanks!

 

[Kingsnake]

I am having difficulty getting the console to recognise the device. I am using Windows with a RP2350 and firmware DSPi-RP2350 v1.0.6 and DSPi Console v1.0.6 (Win x64).

 

[somebodyelse]

Just realized Pico only supports USB 1.1 by its HW.

Pedantry alert: Strictly speaking it's a USB 2.0 controller, but it only supports Full Speed (12Mbps) not the High Speed (480Mbps) we usually associate with USB 2.0.

 

[Kingsnake]

I am having difficulty getting the console to recognise the device. I am using Windows with a RP2350 and firmware DSPi-RP2350 v1.0.6 and DSPi Console v1.0.6 (Win x64).

Got it working with Zadig.

 

[Wesseling Audio Lab]

Got mine working with Zadig as well. Playing Qobuz

What is the purpose of 2 available uf2 files?

 

[Wesseling Audio Lab]

Anyone who has implemented their SPDIF interfaces on their Pico Pi please share a photo and what parts you used for the potential divider and decoupling cap?

in case you didn't find what you were looking for

 

[TurtlePaul]

Would it add a lot of complexity to allow the code to also run on a more powerful rPi model?

Yes, despite the name, the Pico series are mocrocontrollers while the main Pi series are single board computers. Processor wise, they have different architectures.

There seem to be other methods to make a full fat RPi function as a DSP.

Implementing Room acoustics correction using REW – HiFiBerry

 

[Weeb Labs]

Got mine working with Zadig as well. Playing Qobuz

What is the purpose of 2 available uf2 files?

The Pico (RP2040) and Pico 2 (RP2350) need separate builds. Each release includes both, which is why there are two UF2 files.

 

[somebodyelse]

There seem to be other methods to make a full fat RPi function as a DSP.

CamillaDSP is a popular way to do that. There are several threads giving details for various scenarios with different input and output types.

 

[mikessi]

Amazingly useful project to bring DSP active XO to everyone! Thank you OP Weeb Labs.

One question, sorry if it's obvious or already answered: does the Pico get power via USB or does it need a dedicated power supply?

 

[Weeb Labs]

Amazingly useful project to bring DSP active XO to everyone! Thank you OP Weeb Labs.

One question, sorry if it's obvious or already answered: does the Pico get power via USB or does it need a dedicated power supply?

Thank you! It is USB powered

 

[mikessi]

Thank you! It is USB powered

Thanks for that!

And it looks like a DAC or digital audio interface is needed to get an analog audio signal out to amps for multi-ch XO?

 

[Weeb Labs]

Thanks for that!

And it looks like a DAC or digital audio interface is needed to get an analog audio signal out to amps for multi-ch XO?

Yes. The audio outputs are digital SPDIF so that the user can choose their own DACs.