The Raspberry Pi 4 Model B: Game changer for audio?

About a month ago the Raspberry Pi 4 was announced, pretty much blind-sighting everybody.

For the last (many) years, since the announcement of the RPi 2, we had been used to relatively minor incremental upgrades every time a new RPi came out.

Usually the new processor was a bit faster, we got WiFi and BT, then better WiFi, then faster (almost) GbE network, etc. But until now, all of these connectivity options had to be accommodated by a single USB 2.0 port on the SoC.

But this year everything changed. We got a new SoC (the BCM2711), one that finally supported an RGMII interface for a true GbE port, plus a PCI Express port that is used to give USB 3.0 & 2.0 connectivity at useful speeds.

We also got more processing speed and more RAM options, up to 4GB of fast LPDDR4 memory, dual HDMI outputs, etc.

So, all of the above specs mean that the RPi is definitely faster and more capable than ever as a desktop replacement. But is it indeed a better audio streamer for us audiophiles?

For starters, it’s been almost a month since its announcement and availability (I got my unit delivered just 3 days after its announcement) and AFAIK the well-known audio distributions do not yet support it.

Then there is the increased system complexity and power consumption that comes with the new architecture. More power consumption and more ICs usually mean more noise. More noise is never good news for audio.

So I had to do some testing. The idea was to compare the RPi 3 that I had for a couple of years now to the RPi 4.

To keep the playing field as level as possible both of them were running the exact same software (Raspbian Buster Lite, since ATM that is pretty much the only OS that supports both of the platforms) with MPD loaded and were powered by the same (excellent) Salas L-Adapter power supply.

Connection to my DAC (DIY dual AK4493, very detailed) was through USB 2.0.

The music streamed from a NAS box over Ethernet.

I had a friend over in order to at least try to have a bigger sample size (of ears).

The music used was a handful of tracks that we always use for such comparisons (well known material).

We listened using the RPi3, then shut it down and booted up the RPi4, listening to the same material.

Much to our surprise, we actually preferred the sound of the RPi3!

The RPi4’s presentation had something of a “fatiguing” effect. The sound was a bit more “coarse” that that of the RPi3.

We are not talking about big differences here, but they were there. Note that my system is pretty resolving, every change to any component is audible, so YMMV.

I’m not saying that my (our) results are 100% conclusive, but in any case it seems like I’ll be going ahead with my “Audio Pi” project after all (I was considering waiting for the Compute Module 4 to come out).

Comments

comments

8 thoughts on “The Raspberry Pi 4 Model B: Game changer for audio?

  1. Interesting. Can you confirm whether the RPI4 has overcome the compromised clocking the previous models suffered from?

    Believe I read a comment to that effect from one of the engineers in the early back-and-forth after the launch announcement on the official website.

    Did you power the RPIs via GPIO or the Micro/C jacks?

    Got my 2Gb RPI4 yesterday and will try it later today.

    • I haven’t had the chance yet to take a good look into the clocking. I’ll get to it pretty soon.

      But I believe that the engineer’s reference was to an issue with the I2C lines, not the I2S lines.

      Power was provided through the GPIO header on both the RPi 3 & 4.

      It’s good to hear that you are one of the brave ones trying out the 4 before the audio distros are out.. 😛

      • Yes, need to confirm whether there are two separate clock references now.

        Listening to it now, Moode Buster beta ISO. Hooked it up to a ‘lesser’ system initially (laziness) but can instantly switch between the USB RPI4 powered by the C-connector and an Apple charger and i2s 3B (not the plus) powered by an LT3045 via GPIO. So, not a fair comparison as two different inputs and power supplies but my initial reaction is similar to yours. Marginal but if pressed I’d choose the 3B on the i2s. I’ll listen a few more hours then swap the 4 to the i2s and linear PS and the 3B to USB and have a listen again.

        I should really put the 3B on the same Buster-based Moode release to be really fair so the above should be taken with a large pinch of salt but I wanted to compare them this way first to see if the 4 was noticeably different. Step 3 will be to put both on the Buster and try again.

        Frustratingly, my LAds are sitting in another country awaiting collection. Looking forward to them.

        • Interesting, but like you said you will need to level the playing field as much as possible before coming into conclusions.. I’ll be waiting to read up on your progress.. 🙂 My LAd boards are here, but I haven’t built them yet.. I’m using a green prototype board supplied by Salas for testing.

          • Well, it’s been a few days (and nights) of listening to the RPI4 installed in a PCB – previously occupied by a 3B – and powered by the same linear 1A supply as powered the 3B. Both running Moode. Both I2S. So, a swap of the 3B for the 4.
            Think I prefer the 4 in this configuration – linear PS and I2S out. Seems to have a hair more resolution, slightly better bass definition and a ‘feeling’ of more coherence. It’s not huge, it’s slight but I’m going to stick with the 4 in the unit. Usual caveats, YMMV, in my system, with my ears yadda, yadda….

            I didn’t do a comparison between the two on USB out but I didn’t like the 4 on USB – agree with your comments (thought it was ‘edgy’) – but, IMO, it’s a different beast on I2S. Would be interested to hear your take on your 4 via I2S.

            BTW, a quick and dirty measurement returned between 750mA and 836mA running headless via WiFi and nothing connected to USB or Ethernet on the 1A linear supply and playing internet radio. On boot up it occasionally went to 1004mA. Red LED remained/remains solid throughout.

    • I have friends that absolutely love the Odroids, but I’ve heard that their software support is pretty horrible. The RPis have no match in that department. But I keep my eyes and ears open.. I might borrow a unit from a friend and do some testing.

  2. Good day: Thank you for sharing. (RE: RP3 vs.4). Yet, I wonder if the ‘4’ required some settling time ?

    I suppose likely not, as you alluded to the greater capability/ power/ necessary for greater computing power (on a budget) and the noise associated with faster/more capable budget SBC’s.

    Indeed, the RP-2 (sans internal Wi-Fi) may be all that’s required.

    I have three Internet Radio/Streaming set-up’s (one is the RP3/ Gustard U-12 (USB to i2s -AQ ‘Carbon’/Chocolate HDMI) into the X-20PRO -all powered by a Balanced/Symmetrical AC supply.
    SQ is excellent -clarity/resolution and startling dynamics !

    The other is an Odroid C2/Modi 2 Uber and then a (older) Cambridge Audio NP-30 Streamer -Ethernet direct.
    NAS, HDD music sounds much better through the NP-30.

    In any case, it’s clear to me that expensive ‘Streamer’s’ are simply NOT required to enjoy truly excellent sound quality. All ‘Streamer’s are very enjoyable.

    peter jasz

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