Pi2 Design Idiot-Proof Ready-To-Go RPi/AES Streamer

I have used IdPi on both the Mercury and the Pi2AES. No disrespect to JRiver, but I much prefer running Raspberry Pi OS booted from a usb stick with a full linux version of JRiver installed. Its faster, has more features, and is just better. I don't see any benefit to using IdPi.

I have found running Jriver from the Mercury or Pi2AES to be very easy.

 

Hey Mike Kelly

Give that manufacturing the units of the V2 are on hold due to CM4 board shortages, any chance of an acrylic case now?

I "love" my unit and would really appreciate what goes on visually. I know I've mentioned this before and you replied "never say never".
(if you don't ask, you don't receive)

 

The V2 used an off-the-shelf tube-like extrusion from Bud industries. The original V1 used separate plates for top and bottom as well as the sides so it was fairly easy to make the top and bottom in acrylic as well as the front and back. With the V2, it would just be the front and back. So the internals would not be very visible.

 

Cheers Mike,

 

Where can I get a conversion I2S cable to go from Mercury v1 to Audio-gd R27He? Does the version 2 Mercury have adjustable I2S output format? It appears the V1 doesnt?

 

The only real option you have is to go onto Amazon and buy one of those HDMI two wired adapters. They’ll let you individually connect each pair. But it is not a simple task for the average person. I am sorry that our early versions did not take that into account. As you can imagine with the various interfaces out there, trying to find a standard was impossible and so that’s why we made the adjustments in the V2 to allow the swapping to occur.

 

Would you please share the URL of such a product from Amazon.com ?

 

does anyone know will a 15volt 3amp lPS work with either of the mercury streamers?
thanks,
Josh

 

Unfortunately there is a protection circuit that kicks in about 14V. Mercury was limited because the critical clock and AES chain is fed by an internal Linear to 5V regulator. At the current consumption and 12V in it dissipates 2-3Watts. Any higher input would increase that beyond the rating of the part. This method was chosen to allow for an external linear to create a switching free power chain to the critical circuits.

 

Just a heads up that we are working on a new version Mercury. Naturally it will be called Mercury V3 because engineers are super dull and boring! Very similar to Mercury V2, but based on a Raspberry Pi 4 SBC instead of the CM4 Compute Module. The protos are underway and should be built and tested by the first week of November. Once tested pre-sales will start with Dec/Jan delivery.

Key features are:

Raspberry Pi 4 with 4GB, Dual USB3, Dual USB2, HDMI and Gigabit Ethernet
WM8804 AES Transmitter with Ultra-Low Noise NDK Clocks
LM2941CS Low Noise 5V LDO followed by dual Ultra-Low Noise LDOs for clocks and WM8804
I2S over LVDS (HDMI) with PS-Audio or Gustard pinout
Parallel I2S (RJ45)
AES Balanced (XLR)
AES Coax (75 ohm BNC)
Toslink and SPDIF (RCA)
Extruded Aluminum Case

These are new and/or improved features
Internal low noise FAN (<24db) controlled by PWM
12V Input with mini-Noise Nuke (props to @atomicbob)
5.2V @ 5A Power Supply for Pi to support up to 1.5A on the USB Ports
Expansion Header for future internal Dual Mono AK4493S DAC Board

I will be posting some results of the mini-noise nuke (noise nuke jr?) in a later post

3D Captures

 

Started a new thread for the results of our noise nuke jr (?) testing.

https://www.superbestaudiofriends.org/index.php?threads/mini-noise-nuke-measurements.13852/

 

Do you consider adding SFP module (for optical network connection) as well as fanless cooling system for Mercury V3?

 

SFP has too small a customer base at this point in time. As for the cooling, we will have a heatsink, but the Mercury case size does not give us much room to work with. The fan we plan to use is a low noise (<20dB) fan and it will be PWM controlled by the CPU so only on when it gets above the set temp. In our experience, the CPU does not work that hard when doing just music. We have some more testing to do to finalize all this. Initial proto testing will begin next week. Than we will be able to do some acoustic noise measurements.

 

Michael have you considered doing an RPi5 based streamer with added clean usb out via pcie bus? It's only pcie gen2 x1 but for usb 2.0 it's more than enough

 

For the uninitiated, do you mind explaining why you expect this to be better? Is this for a specific use case or because of some theoretical benefit?

 

Lower noise and better clocks, same as spdif.
Allo makes a streamer based on a similar idea called the USBridge Signature (although they use a Compute Module with custom daughterboard) but the IC they use has an unmaintained driver which fails to build on newer kernels which will eventually cause the device to become obsolete due to lack of chip manufacturer support. A streamer based on a stock RPI and a well-supported USB controller wouldn't have that problem, hence the question.

 

There would be little or no benefit from an audio point of view. The highest quality output you can get is to use the I2S interface of the raspberry pi itself. USB is always a compromise and requires much more effort to clean it up. And then you have to rely on the DAC you are using to have a very good USB implementation as well.

PCIe also makes no sense because you have USB three coming out of the pie already. Internally that is using a USB three controller on the internal PCIe bus. You end up duplicating things that are already there.

I feel that a Point that often gets lost in these sorts of discussion is that audio is really, really old tech! It requires very little processing power, nor extensive circuitry to deliver very good results. Layering other interfaces and topologies and software conversions, is in my opinion, dumb.

 

Has anyone tried full desktop operating systems with their Mercury - eg Raspberry PI OS, Ubuntu, etc? If so, do the digital outputs function correctly?

Having used a Pi 4 separately for a few years in place of a Windows PC, I do feel that the horsepower in the Mercury is somewhat wasted just running Volumio or Moode. Nothing against Volumio or Moode, but it would certainly nice to use the Mercury for multi-tasking whilst listening to music (even if this isn't the intended purpose....).

 

After several week of much reading and experimenting (and figuring out how to configure Gentooplayer, and also with the assistance of some friendly gents from Audiophile Style) got it working

Must say I am mightily impressed. The clarity, soundstage and overall response are superb. All far better than a Lumin D1 and Holo Red

About 10 days ago, the Kernel was upgraded to 6.6.1 and this improved it further

Using an AES cable from the Pi2 to the DAC. This was one I made up myself using 110 ohm cable, Managed to get a Shunyata XLR digital cable. Another, perhaps more subtle improvement

Most of the music is sourced from a 4Tb SSD but I have also tried Tidal

All the digital outputs operate. I tried SPDIF co-ax and Optical. Not as good as AES

Using MPD player on an iPad. No artwork. Program is fairly well behaved

 

In my opinion, Gentooplayer is far way the best software for Mercury Lightweight and fast real time kernel options, the ability to make low level customizations/tweaks makes it unique although it requires some technical knowledge to do it. I'm glad you experienced that with Devialet, as well.