I’ve just built a Bluetooth speaker (see photos) using Dayton Audio drivers, 30W amp board, lithium battery pack/19v power supply and rear plate controller from Wagner Electronics.
The look I like is a clean and minimalist timber finish with hidden electronics and calming curves. The speakers are in two sealed compartments with the electronics in a separate centre section (also sealed).
I’m very happy with the sound but the amp board is Bluetooth only and I’d like to try out a Wi-Fi-enabled streamer for my next project to make the most of hi-res streaming services (Tidal). The sound quality difference between Wi-Fi and Bluetooth streaming is very noticeable to me.
My key wishes for the next project are:
audiophile quality sound in a small form factor
Wi-Fi streaming only (DAB tuner would be a good add-on but not essential), no external device connection required, preferably no external aerials, Bluetooth ok as an add-on
a good amp (say 2 x 30W at 8 ohms) and DAC chip
amp, drivers and electronics within single enclosure (but in separate sealed compartments)
hardware on/off switch and large volume control on front or top (no other external controls)
portable (within the home, can be powered via a wall wart)
value for money
One option I’m considering is to go with a Raspberry Pi board running Tidal Connect on Volumio along with a Pi Digiamp. I prefer ‘plug and play’ connections but can do some basic soldering if needed (although my soldering iron is old, 50w and has a large tip). I have no programming skills and would need to cut and paste code from manuals/tutorials. I use Apple Mac/iPhone only.
Could you someone advise if this setup would work? Some of my questions would be:
Which Pi board would you recommend?
What is the Pi Digiamp the best available? How does it compare to say the Hifi Berry? Are there any others?
Can the Pi operating system (Volumio) be loaded with a USB thumb drive rather than an SD card (I would have to get both a card and a reader but have plenty of thumb drives)
Is a separately mounted hardware on/off switch and volume control possible with the Digiamp board?
Would the central electrical compartment need venting or would heatsinks be adequate (will be run at moderate volumes)?
Can the Pi/Digiamp combination be powered by a lithium battery pack such as this:
Is there a similar product specifically for the Pi?
I’d almost exclusively go with the Pi 4 here. Anything else will be too slow, unsupported, or in the case of the Pi 5 potentially be incompatible with the older tutorials and libraries you’d need to use here.
The Pi Digiamp+ is the highest spec’d Pi Digiamp I am aware of, although the IQaudIO and HiFi Berry boards usually go up to higher resolutions around the 192kHz at 24-bit mark. You’ll have to decide which is best value-for-money for your project and what you’d like to work with
Yes, although you’ll probably need an SD card to flash the bootloader of the Pi to use USB boot initially.
Hm, not directly with the Digiamp board as far as I know, although there may be a way to use a script running on the Pi to initiate a safe shutdown with a separate push button if you’re so inclined.
I’d say heatsinks would be fine here, although they won’t be doing much work without open air exposure. Fitting a fan to the back with some appropriate venting would almost certainly be your best option for cooling
Not sure about that pack specifically, I’d have to check the draw of the whole system and the required voltage from your specific Pi, but yes, the idea is definitely “sound” (sorry for the pun ), no problems at all using some LiPOs for powering this with appropriately rated voltage and current draw.
Thanks Bryce for these helpful replies. Will follow your proposal and pursue the Pi 4.
I am wondering in the case of a Pi 4 plus Digiamp+ combination which DAC is used for music streaming from Volumio (I presume the Digiamp doesn’t have one and the Pi 4’s one is not of high quality). I currently stream into my DIY bluetooth speaker from a Bluesound Node 2i using its bluetooth out, but I’d like this next wifi project to be independent of the Bluesound.
So I’m thinking I may also need a Pi-based DAC to retain Tidal streaming quality - in other words a ‘triple decker’ of Pi, DAC and amp. The only ‘plug and play’ triple-decker products I can find so far in the Pi world are the JustBoom Amp which sits on top of its Digi HAT and the Allo Mini Boss Player Plus which uses the Pi Zero but comes with a useful stepped attenuator. The latter gets good reviews but is the Zero up to the task? If the Pi Digiamp+ is the best available, do you know if the Pi DAC (or indeed any other DAC) can be stacked with it? I’d rather go with high quality sound and sacrifice the hardware volume control volume.
Welcome! Loving your passion for excellent sound.
For best results, we might consider what speakers you intend to use with this amplifier.
It may be that an external amplifier is a strong choice. Would you be willing to sacrifice the ‘triple decker’ solution if it allowed you to impedance match for example?
Pix
P.S. The photos of your Bluetooth system is lovely.
Afaik the current Digiamp+ has TI’s TAS5756M PowerDAC built in which according to the specs is rated for an output of 2x35wpc here’s the datasheet on it for you if you need further specs:
You’ll need to check for pin/address interference and max load off the GPIO for your specific Pi, depending on the pins and protocol the HATs/breakouts you decide to use are based off, that’ll let you know whether there’s any pins being used by both.
On the 4 (RAM and revision independent) you can draw a max of 50mA off all GPIO combined, and < 16mA per GPIO (excluding the 5V and 3.3V rails of course), I doubt you’d get close to this with only a couple HATs, but still something to be aware of. It’s covered under the table in this section of the RPi docs:
You could run with a Zero, although the limited 512 MB of RAM (the lowest spec’d Pi 4 still has about double this) and 1GHz single-core CPU versus the 1.8GHz clocked quad-core on the 4 will be a fair bit slower to run and limit the amount of memory available for your applications and OS to use while running. Definitely possible to use the Zero or a Zero 2W, although the 4 is better in almost every spec.
Thanks Pix for your kind comments. An external amp will certainly be better sonically but I want to find out what sound quality can be achieved with a one box solution at reasonable cost. My goal is to create an audiophile streaming ‘boombox’ that can be used anywhere in the home without fuss – conceptually a Wiim amp or Bluesound Powernode with speakers attached.
In terms of the speakers, my Bluetooth speaker used the Dayton Audio PS95-8 full range speakers which sound great in the mids and trebles but lack some bass. I experimented with port length and cabinet dampening which has helped. The Tasmanian blackwood baffle (I’m in Australia) adds some wonderful warmth which I wasn’t expecting.
For this project I would be looking at a 2-way system (mid/bass and tweeter) with drivers from makers such as SB Acoustics, Mark Audio and Scan Speak. Box size is the critical factor here, probably 4 litres min and 6 litres max per driver, so this will constrain the choice considerably. Full range or coax drivers also possible. Suggestions welcome!
Bryce thank you for that additional info and specs. I didn’t know the Digiamp+ had a TI PowerDac, this may be the way to go, at least to start with. The TAS5756M may not be as good as a standalone DAC but it may not make a huge difference in this setup. I would need this forum’s wonderful help to start soldering CPIO pins so perhaps that may be a later mod? The Zero only came up because Allo use it, but I would prefer the 4 for a self-build, perhaps adding a standalone DAC board later if the sound from the Digiamp+ is still lacking.
), no problems at all using some LiPOs for powering this with appropriately rated voltage and current draw.
