Holo Audio Red

I finally got a Holo Audio Red at my place. I'm going to share my brief thoughts as I don't find streamers all that exciting.



Build
It's a solid hunk of aluminum and the red color is much more laid back in person compared to photos. I appreciate the built in power supply to reduce any LPS anxiety. No complaints here.


Sound impressions
I noticed what I almost always noticed with upgrades in source/streamers - a reduction in digititus most noticeable in the higher frequencies. For me this presents with cleaner female vocals, specifically the reduction in sibilance on S's and T's. Also more plankton and blacker backgrounds.

All of these improvements were noticeable on my test albums / songs, but they were not hugely improved over my beloved PI2AES OG with @atomicbob NoiseNuke. If I was forced to give a percent improvement in the mentioned areas I would go with 2 to 3 percent (IMO).

To me the improvement is worth it to further reduce any fatigue at loud listening levels. But, I'm at the point I'm looking for any small percent improvement.


Personal Streamer rankings - UPDATED

Holo Audio Red using AES --> PI2AES OG w/ Noise Nuke using AES -->Holo Audio Red USB to Unison ----> USB Bridge Signature to Unison

DISCLAIMER
I still think a high quality source is important. However, depending on your budget, just go with a PI2AES Lite or OG and call it a day for half the price of the Red. Add a Noise Nuke and forget about it.


Gear
PC hosting ROON Core -> PI2AES OG / Holo Audio Red-> AES/ USB -> Yggdrasil LIM -> DNA Stratus V3 -> ZMF Blackwood Aeolus / ZMF Atrium / ZMF Verite Open


Let me know if anyone wants me to try the DDC feature or anything else a bit strange. I unfortunately do not have a DAC that can take advantage of this units very high bit rate options over USB or I2s. I would imagine this would be a major benefit to folks using Holo DACs.

Update: Tried USB from Red to Yiggy LIM with Unison. Definitely a downgrade from using an AES cable. Still better than most other USB streamers I've used.

Update 2: Tried USB out again with Yiggy LIM but with a DNA Stratus V3 instead of V2. This is by far the best sound I've ever had. Not sure if the recent Red firmware is the culprit or I'm going insane.

Update 3: After a firmware update, reinstall and using a different AES cable my initial impressions stand. AES is preferred to Yiggy LIM with USB A close second.

 

Thanks for the review, I've been slowly eyeing a new streamer solution to eventually take over from my Pi2AES. I also had a 502DAC, but the coaxial out has become really problematic and unusable, and now my Pi2AES coaxial has been acting up sometimes as well (BNC and AES XLR work fine for now). With the price increase and deletion of AES XLR from the Lite version, I don't think it is anywhere near a great value as it was a few years ago (yeah I get it parts price increase etc), but now I'm questioning the reliability as well (I have tried multiple different coax cables and new Moode images to no avail).

I find the Mercury Streamer's price hard to swallow for basically a Pi2AES in a housing that accommodates a SSD. I would prefer the option of having both those items separate for 1/3 the price. For $800 or so I expect a polished product and it looks like the Holo ticks that box, how do you find the user interface?

 

It's very simple. Once you find the IP address you are presented with one page of info. Basically select what streaming features you want to use (I just use Roon Bridge) and how it should handle DSD (which I don't use). I'm not positive on the USB redirector option. The manual doesn't mention it.

EDIT: The USB redirector seems to be the DDC feature. Yiggy Unison showed up as an option once I plugged it in both there, or as an output device at the top.



And, good points you made @JK47. The parts shortages and insane price hike on Pi4 boards does sort of complicate the price to performance ratio at the moment.

 

feel free to send the PI2AES back for repair. Just pay for the shipping and will take care of it.

 

@Michael Kelly has always been a stand up guy, taking care of any issues I’ve had with my 2 Pi2AES (both of which ended up being jumper / user issues).

Also, I got a Mercury V1 and find it a small improvement over the Pi2AES and running off 12V is a lot more convenient for me.
Also, it draws less power than a Pi3 + Pi2AES so I can easily power it with my LPS-1.2 and not fear to push it too hard (it’s barely warm)

 

Thanks @RestoredSparda for the nice write up. I don't have either the Mercury or the Holo Red. But I'd like to point out a couple of differences, based on the webpage information.

The Mercury uses Raspberry Pi 4 compute module thus it can be used as a local music server and a player (streaming device) at the same time because there is a NVMe M.2 SSD slot on board. The Raspberry Pi 4 compute module does native support to SSD, thus the speed of data access will be fast (theoretical faster than the USB3 on the Pi 4 to an external HD). The Mercury also has a Wi-Fi antenna, thus it can run wirelessly.

On the other hand, the Holo Red uses the Raspberry Pi 4 compute module as well, but it does not have a SSD slot (by looking at the pictures, I didn't see a space or socket for a SSD). Whether it can connect to an external USB drive to be able to setup a local media server, I don't know. I didn't see a Wi-Fi antenna neither. Compared to the Pi2Design's Mercury, it added the functionality of a regular DDC, which allows the users to connect to a USB output of a computer or iPad and to use the Holo Red to convert USB music to SPDIF or I2S for your DAC.

 

external usb on both Mercury and holo red are 2.0, 480Mbps. NVMe uses PCIe Gen 1 which is 5Gbps or - 10x. Obviously the SSD itself matters as well.

 

I asked the question about Wi-fi and RED doesn't have Wifi, that's the response I got from head-fi crowd.

 

The picture on their website shows the compute module without Wi-Fi. That just seems kind of dumb. I know there’s a lot of nervosa around Wi-Fi, and some of it’s legitimate, especially with the raspberry pi and the printed circuit board antenna. But on the compute module in Mercury we use the external antenna connector so that the RF energy is fully shielded from the module to the antenna outside the box. And once it’s outside it joins all the other RF crud that’s flying around your house!

 

Interesting.. any thoughts about using a WiFi dongle on Pi2AES instead of the internal wifi? Is the concern legitimate for both Pi3 and Pi4?

 

Unfortunately the latest trend in audiophile world is the usage of FMC, Network switches with external clock etc and hence devices which come without Wi-Fi are perceived as “Hi-Fi”

 

The Pi2AES with Pi4 can be used as a DDC. It relies on software configuration to enable the functionality. While I haven't implemented DDC functionality on a Mercury, its Pi4 Compute module has the necessary hardware (USB with OTG support).

Edits: added note on Pi4 and Compute module. AFAIK other full-sized Pis don't have the same USB OTG functionality.

 

I haven’t tried it but with GentooPlayer and Diretta one can convert any pi based device to DDC. I think @lithiumnk is using Metrum Ambre as DDC

 

The issue is that unless the PI is in a metal box there is some RF pollution. That said a dongle with an extender cable would put the WiFi antenna further away and thus reduce the strength of the RF at the board.

Holo Red with a dongle should achieve the same results as our Mercury with regard to RF.

 

BTW, there continues to be confusion about AES. The BNC on the LITE is AES3id or AES Coax. It is missing AES3 or AES Balanced. Exact same protocol and data.

https://www.pcmag.com/encyclopedia/term/aesebu

 

I should have clarified AES XLR connection, which I find to be a more positive and robust connection.

 

My implementation used the USB OTG port to feed into HQPlayer, which then output to the Pi2AES digital outputs. That allows upsampling of Spotify, youtube, games and other general audio content.

 

I’ve had my Holo Red for about 2 weeks. It sounds phenomenal and I’m pretty comfortable with the notion that it is probably the best digital streaming device I can get for my Spring 3 KTE. The color looks fantastic and appears a bit too bright on photos. It is a really rich red color. It’s also heavy AF. Mine weighed 5 lbs. 6 oz.

I am using JPlay for Qobuz via UPNP to the Red which is the primary use case I wanted to cover. The secondary use case is probably not going to work and I am a little annoyed by that. The Red is running upmpdcli which I would guess is the foundation for nearly any streamer out there. It’s new to me, but it looks like a very useful software. I am wondering if I can use UPnP on my server and access my music library that way. I have to read into that.

The Red is a USB input digital to digital converter and a network streamer. However, you cannot easily make this switch and it is not officially documented anywhere how you are supposed to achieve this. It turns out if there is a USB input device plugged in, the CM4 module will not boot and the Red will be in DDC mode only. If there is no USB device plugged in, then you get the CM4 booted and it will be accessible via network. I figured this out after about 60 minutes of swearing and finally reading the HF thread. Swapping back and forth requires a power cycle as well.

This is extremely not ideal and difficult to use IMO. What this means is that if you install the Red nicely into your audio stack/rack, you would have to physically unplug and plugin the USB cable in order to change states from DDC to streamer. I find this incredibly frustrating. I was hoping this device would allow me to easily swap between USB based playback from my Linux MPD server to Qobuz and back again with no trouble. As far as I can tell, it will not cover both use cases easily.

I am using the Red via HDMI I2S to my Spring 3 KTE and I am not surprised that it sounds phenomenal. Bits are bits, but I’ve always felt like streaming was a bit off for some reason. Now, I think streaming through the Holo Red may be the best PCM source I have. I need to do more A/B but I am throughly impressed, despite the usability issues with the DDC/Stream functionality.

 

Maybe you can add a USB KVM switch (e.g. one with 2 inputs) and toggle between the populated input and the unpopulated input to switch between DDC and streamer upon reboot?

I agree that it is really inconvenient, though…

 

Super easy!!