Note: I also posted this in the diyaudio.com forum. Since there´s a higher chance
that I can be better helped with my volumio specific questions on this forum,
I also post this here. Also, I think that it might be interesting for you guys.
I started sourcing parts for my latest project and I would like to hear some
feedback from you guys about whether I am on the right track or not so…
To justify some of my picks, first I wanted to use some parts I have anyway, like
the 5" display, the Pi,the bamboo front plate, the OLED display,… and second, I am a polymer materials
scientist guy and therefore I am totally into Aramide speakers and fancy Polyimide AMTs … :mrgreen:
I also wanted quite some high quality sound without paying more than 200€ for
the whole thing.
I have a CNC router where I am going to carve the Bamboo wood plate and metal front with.
Ok, so here’s the mockup I made since I wanted to see how It’s going to look upfront without doing too much CAD work first:
Ok, first let’s start with the speakers:
I have chosen this woofers which I have a mixed feeling with, first they are quite
cheap, have a good size for the project and they look damn sexy , on the other hand they might not be as Hi-Fi as I wanted it to be … let’s see.
Skytronic 5 1/4" Woofer, 100W RMS, 8Ohms, Range: 35 Hz – 8 kHz
As for the midrange/full (let´s see If I use filters) I am going to use this (I don´t know if its original H/K or chinesium fake):
Harman/Kardon 2 3/4", 12W RMS, 6Ohms, Full-Range
And for the highs, I fell in love with this little beasts:
No-Name Polyimide Ribbon (“Air Motion Transformer”) 2" , 15W, 8Ohms, 3,3 KHz-40 kHz
I have little knowledge about speakers, but to me It looks like this combination
will be useable. The “full spectrum”/midrange could be driven with the full
spectrum or just the mids… I have no clue what´s better in this case.
Also, I will use two 2.1 class-D-amps which have a crossover built in (can be
adjusted too) and so the bass is already separate. I could then put the full sound
range straight out of the amp to the full range speakers and then use just one
highpass for the AMT-tweeters. Would that be feasible?
Let´s see what I will be using as an amplifier:
TPA3118 2.1 30W/30W/60W Digital amplifier
I have chosen this since the new TPA3116/3118 have excellent reviews and seem
to be superior to the already good TDA7498 class-D-Amps. The advantage here
is that it has an active crossover already built in, so I will be using two of this
which will give me 4.2 channels (with stereo audio off course). So I have 2x 60W
for the woofers and 4x30W for the rest, which is more than I need. I am not sure
if I will use two channels for the tweeters and two for the midrange or just use
two channels and omit the unused two.
I think I need some advise at this point since I am not quite sure if this is a good
Idea or not.
Maybe an other amp? Different wiring? DSP? Crossover?
Next up is the DAC. I already have this one:
HifiBerry DAC 2.0 clone with TI PCM5122 silicon:
It produces great sound and I am satisfied. Had this part already in use and so I
will likely keep using it. I have an eye on this one:
I2S DAC with AK4495SEQ silicon:
aliexpress.com/item/AK4495SEQ-D … 01584.html
So, I am not sure if this will actually make a difference with the complete setup.
The DAC seems superior, I could swap opamps If I wanted and such. But I am not
sure If I would actually hear a difference for twice the price. Advice?
For the other stuff, I have a yellow 128x64 OLED screen which would display
track info or an EQ or so… Had this in my parts bin and never found a use for it.
on the mockup it looks great.
The raspberry pi is either going to be a pi1 model B rev 2.0 or a pi3. I have both
and initially wanted to use the pi3 since I thought the pi1 model B didn’t have an
I2S port. It turns out that the pi1 rev 2 DOES have an I2S port, although there is
no header. I would have to solder it.
Does anybody have experience running volumio on a pi1? I think that using the pi3
instead of the pi1 would be overkill for just a music player and the pi1 is unused
anyway at the moment, so It would be a shame not to use it. So it´s likely going to be
the pi1 which should be fine for volumio. Btw, I want to use Amazon Alexa with it
too. Amazon recently opened the Alexa API and it can be used on DIY projects.
As display I use is this:
5 Inch Touch Screen HDMI 800x480 TFT:
amazon.co.uk/d/Computers-Ac … 013JECYF2/
I am already using some for several projects and I am happy so far. Colors are a bit on the washed out side since it´s no IPS panel but for the price It’ s fine. Size is about perfect for this project.
Knobs and “glue logic” will be made as I go. I will also be updating this thread and make a bit of a log here.
So, before I just start and fail, I first wait and hope for some feedback and possible better ideas regarding amps, speakers, wiring and such.
What do you guys think?
Best regards, Phil