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Tag: hifi

E1DA PowerDAC V2 Review

Have you ever dreamed of being able to drive a full-size planar with a simple usb dac/amp dongle? I have, and I have always wanted a portable device with plenty of power and a parametric EQ integrated. It exists and its name is PowerDAC V2.

What is it?

The PowerDAC V2 is what we usually call a portable dac/amp combo but … without a dac. How? Well, it is a Full Digital Amplifier (FDA), it receives the digital input from the source, it converts it to PWM which is fed to output transistors and then filtered.

Specs and pictures

  • Dimensions:                   75×45.5x19mm
  • Weight:                           68g
  • Power:                             USB 5V power rail no internal battery, 250mA idle current, the device contains up to 5000uF of capacitance and IOS/Android devices can start OTG operation only with Camera_Adapter and USB OTG Y-splitter cable respectively
  • Input:                               USB PCM up to 24b/192kHz
  • Output:                            digitally generated PWM 384kHz + passive LC demodulation balanced output 2.5mm jack 5mm shaft stopper, A&K pinout
  • Output impedance:       1.5Ohm@1000Hz FFT flat top -6dbFS 32Ohm/open load, -.4db drop 
  • Output power:                >320mW@32Ohm@1kHz@THD=1%
  • Output power:                >580mW@16Ohm@1kHz@THD=1%

For full details check the website linked at the end of this review.

As we can see from the specs this device fills the niche of transportable dac/amps, perfect to connect to your laptop while working or studying. If you are asking yourself if you can use it with a mobile phone the answer is: technically yes, practically no. If you try you would have: smartphone, usb y-splitter, PowerDACV2 and a powerbank. This is not my definition of portable so I don’t advise to use it with a phone as source.

As you can see from the pictures it is a shiny little metal box. I really do like the mirror-like plates although they will remain like this only for the first 2 minutes, after that they will be covered by your fingerprints. On the back you can read how is the internal circuit composed, geeky!

When it is powered on it will become warm, don’t put it in your pocket and make sure to use it in free air if you don’t want it to become uncomfortably hot!


I’m currently testing the PowerDAC with my 1MORE Quad Driver, I’ve bought a balanced cable for my Hifiman HE-560 and I’ll update the review when it will arrive.

On the website the sound is described as “razor-like detailed” and “max transparent and max detailed” and the description is completely realistic. Don’t expect to have a warm, colourful sound of a tube amp. The sound is as it should be: detailed, neutral.

With my hybrid iem the background is not completely black, there is a very low background noise so I don’t recommend to use it with low impedance, high sensitivity multi BA iems. (If you use them check the website at the bottom of the review, E1DA produces a portable dac/amp based on ess9038q2m that would be more suitable for you)

Only while playing certain songs I could notice some sibilances and, in general, a slightly harsh sound on highs. My main hypothesis is that the cause is a bit of third harmonic distortion.

All in all I’m really enjoying the sound and the huge amount of power that the PowerDAC is able to delivery to my 1MORE iem. Be sure to check this section of the review when I’ll update it with my impressions about He-560. (It is important to mention that the PowerDAC was designed to be able to drive a pair of HE-400i, certainly not the easiest over-ear headphone to drive)

HPTOY App and the DSP

To control the volume and all the DSP functions you need to download the HPToy app, available both for Android and iOS. The communication between your smartphone and the PowerDAC is via bluetooth low energy. Due to the metal housing the bluetooth range will be fairly short.

In the app there are the following controls: volume, bass/treble, loudness, filters (pEQ), compressor.

For a detailed explanation of every single feature check the official website, in this review I’m going to write only about the most important: the parametric eq.

When you tap on “filter” the app will rotate in landscape mode and you will be able to use a 7-band parametric equalizer. Below you can see a screenshot and a video tutorial about how to use it.

I think it’s totally useless to say how much can be powerful this feature. The only thing you need to do is visit the following repository:, look for your headphones, download the .png image, import it in HPTOY, stretch it to match X and Y axis, mirror it and then create the EQ following the error curve (the red one). I do not recommend to use the written pEQ values if you want a good result.

If you have an iPhone or an iPad you can create an EQ using biquad coefficients too! This allows you to build a more precise equalization and to use also different type of filters like: low shelf, high shelf, notch, high pass, low pass, band pass. To calculate the coefficients you can use a website like this: (set SR to 96000Hz)

Once you have made your EQ you can save it and even export it as a preset. There are already a lot of in-app available presets for a long list of headphones, but being able to export and import them is a huge advantage for all the PDV2 users.


I usually try to be always objective about audio quality and to not jump on “the hype train” when an interesting product is released. The PowerDAC V2 is a good all-rounder with tons on features, a good audio quality and a lot of power to drive pretty any kind of headphones on the market. The website is full of technical details and you won’t find a single line of marketing bullshits for audiofools. I would easily pay 150€ without any problem for this little shiny metal box and even at 150€ it would be competitive compared to other dac/amp transportable combos. The main “problem” is that you can buy the PowerDAC V2 at 50€, and at this price is one of the best bang for the bucks that I have ever seen.

Nice job!

Official website:

E1DA Products Discord chat:

Head-fi thread:

Logitech Media Server and FreeBSD

There are 3 ways to install Logitech Media Server on you FreeBSD computer: ports, packages and DIY (yes … you have to compile everything)


Just type:

pkg install portmaster
portmaster audio/logitechmediaserver

IMPORTANT: while configuring the options of all softwares you are going to install, when logitechmediaserver options will be prompted make sure that “TEST” will NOT be ticked.

Note that the last update of this port was at the 11th July 2017.

Package build by me (recommended)

Ports are not constantly updated so I decided to create an installer script which is easy to maintain for my personal use.

This will install Logitechmediaserver 7.9.2 updated at commit 2433703 with these included binaries:

  • SoX with DSD support
  • Flac 1.3.3
  • Faad2 2.8.8
  • Wavpack 4.80.0

Instructions (must be executed as root!)
pkg install wget ca_root_nss
chmod +x

Last update: 13th of October 2019

Installing LMS from my installer script means that you are accepting Logitechmediaserver license -> License_eng

DIY, aka: compile everything from source

Before starting this is what you need:

  • libtime.a
  • libpatience.a
  • Knowledges about what are jails (I will use CBSD to manage them)

Let’s start creating a jail that we will use to build everything:

cbsd jconstruct-tui

In “pkglist” insert manually:

unzip bash gmake rsync nasm wget libgd gcc perl5-5.24.1 automake libtool

Enter in the jail:

cbsd jstart build
cbsd jlogin build

I’m going to use /tmp to download everything and build lms:

cd /tmp
unzip 7*
tar xjf l*

Let’s start compiling:

cd slimserver-vendor-public-7.9/CPAN
./ -t | tee /tmp/build.log
cd /tmp/logitechmediaserver-7.9.1-1489743085/CPAN/arch/5.24
rm -rf 5.1* && rm -rf 5.8 && rm -rf 5.22 && rm -rf 5.20
cp -Rp /tmp/slimserver-vendor-public-7.9/CPAN/build/arch/5.24/amd64-freebsd-thread-multi .
rm -rf x*

cd /tmp
tar cf FreeBSD-lms-7.9.1.tar logitechmediaserver-7.9.1-1489743085

tar xf f*
cd flac-1.3.2
autoreconf -i
./configure --enable-static --disable-shared

cd /tmp
cd faad2-2.7
./configure --enable-static --disable-shared

cd /tmp
tar xf wavpack-5.1.0.tar.bz2
cd wavpack-5.1.0
autoreconf -i
./configure --enable-static --disable-shared

Now we have to exit from this jail and move everything we have just compiled to a new jail when logitechmediaserver will run.

First of all exit from the build jail:


Create a new jail like we did before including the following packages:

wget perl5-5.24.1 libiconv

cbsd jstart lms
mv /usr/jails/jails-data/build-data/tmp/FreeBSD-lms-7.9.1.tar /usr/jails/jails-data/lms-data/tmp
cbsd jlogin lms

Now I’m going to copy lms and the binaries we have compile above in the “lms” jail. I will include the modified version of SoX able to convert in DSD; for further info: Logitechmediaserver, C-3PO and PCM to DSD conversion

cd /tmp
tar xf F*
pw groupadd -n lms -g 20000
pw useradd -n lms -u 20000 -g lms -s /usr/sbin/nologin -c "Logitech Media Server" -d /nonexistent
mkdir /usr/local/lms
mv logitechmediaserver-7.9.1-1489743085 /usr/local/lms/
cd /usr/local/lms
mv logitechmediaserver-7.9.1-1489743085/* /usr/local/lms
rmdir logitechmediaserver-7.9.1-1489743085
rm -rf Bin/a* && rm -rf Bin/i* && rm -rf Bin/p* && rm -rf Bin/s* && rm -rf Bin/x*
cd Bin
mv sox-FreeBSD sox


Move flac, faad, wavpack binaries into the Bin folder of LMS:

mv /usr/jails/jails-data/build-data/tmp/flac-1.3.2/src/flac/flac /usr/jails/jails-data/lms-data/usr/local/lms/Bin/
mv /usr/jails/jails-data/build-data/tmp/faad2-2.7/frontend/faad /usr/jails/jails-data/lms-data/usr/local/lms/Bin/
mv /usr/jails/jails-data/build-data/tmp/wavpack-5.1.0/cli/wvunpack /usr/jails/jails-data/lms-data/usr/local/lms/Bin/

Back into lms jail:

cbsd jlogin lms
chown -R lms:lms /usr/local/lms
chmod -R 755 /usr/local/lms/Bin
mkdir /var/log/lms
mkdir /var/db/lms
mkdir /var/db/lms/cache
mkdir /var/db/lms/prefs
mkdir /var/db/lms/playlists
chown -R lms:lms /var/db/lms
chown -R lms:lms /var/log/lms
cd /etc/rc.d
chmod 555 lms
echo 'lms_enable="YES"' >> /etc/rc.conf && echo 'lms_logdir="/var/log/lms"' >> /etc/rc.conf && echo 'lms_cachedir="/var/db/lms/cache"' >> /etc/rc.conf && echo 'lms_prefsdir="/var/db/lms/prefs"' >> /etc/rc.conf && echo 'lms_playlistdir="/var/db/lms/playlists"' >> /etc/rc.conf


Now restart the jail and Logitech Media Server will start at boot (if you are lucky 😉 )

cbsd jstop lms
cbsd jstart lms

Logitechmediaserver, C-3PO and PCM to DSD conversion

In this tutorial I’m going to illustrate how to implement and enable PCM->DSD conversion on-the-fly on Logitech Media Server. This is possible thanks to the plugin C-3PO and a modified version of SoX and Squeezelite-R2.

For a complete introduction and description of what is Logitech Media Server and how to install and use it you can read this Marco Curti’s guide -> Introduction to Squeezebox Server (translation in English will be available soon)


First of all we have to substitute the original SoX binary package in LMS with the modified one; go to the directory that contains LMS binaries:


cd /usr/share/squeezeboxserver/Bin/ARCH

Where “ARCH” is the architecture of your operative system.


cd /usr/local/share/logitechmediaserver/Bin


cd /Library/PreferencePanes/Squeezebox.prefPane/Contents/server/Bin/darwin


cd C:\Program Files\Squeezebox\server\Bin\MSWin32-x86-multi-thread

Then remove the “old” sox, download the modified one and rename it in “sox”.

*nix O.S.

rm sox && wget https://audiodigitale/repo/sox-VERSION

You can find all the versions of SoX for different O.S. here -> Download SoX

The binaries in the download area are statically linked, so you don’t have to install any dependencies!

If you want to compile SoX by yourself in the download area there is the .tar.gz archive of the same version of SoX used to compile the binaries; otherwise you can also clone this github repository
-> mansr/sox

If you have any doubt follow this guide -> How to compile SoX


To install C-3PO please insert this repository in the lms plugin page :

If you want to read more documentation about C-3PO follow this link -> C-3PO Transcoding Helper (translation in English will be available soon)

Project with source code on github -> marcoc1712/C-3PO

Particular instruction for FreeBSD: in this O.S. the directory that contains the binary of perl is different from linux, so you have to modify this file:


and replace #!/usr/bin/perl with #!/usr/local/bin/perl


Now your server should be ready to trascode PCM files to DSD, we just need to setup the client:

Please download the correct version for you O.S. here -> Squeezelite-R2

If you don’t know how to use it please read this guide -> Squeezelite-R2 Guide (translation in English will be available soon)

If you want to compile Squeezelite-R2 by yourself in the download area there is the .tar.gz archive of the same version of squeezelite-R2 used to compile the binaries; otherwise you can also clone this github repository -> marcoc1712/squeezelite-R2

If you have any doubt follow this guide -> How to compile Squeezelite-R2

Do you want to install and setup every single option of squeezelite easily? You can do it with Falcon, a practical and user-friendly web interface to manage every aspect of squeezelite! (Only for linux, beta)

Do you already know how to use squeezelite and you just want to start it at boot time?

Init Script (Linux)

sudo nano /etc/init.d/squeezelite

# Provides: squeezelite
# Required-Start: $syslog
# Required-Stop: $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Script per l'avvio di squeezelite
# Description: ---


OUTPUT= # Specify output device, default -> default, - = output to stdout
NAME= # Set the player name
LMS= # <server>[:<port>]
ALSA= # -a <b>:<p>:<f>:<m> Specify ALSA params to open output device, b = buffer time in ms or size in bytes, p = period count or size in bytes, f sample format (16|24|24_3|32), m = use mmap (0|1)
BUFFER= # <stream>:<output> Specify internal Stream and Output buffer sizes in Kbytes
SCHEDULER= # <scheduler>:<rt priority> Scheduler: other, fifo, rr. Priority: 1-99 -> 1 min priority 99 max priority
NICENESS= # nice level -20 max priority 19 min priority


case "$1" in
echo "Starting Squeezelite"
start-stop-daemon -S --chuid $USER -N $NICENESS -P $SCHEDULER --exec /squeezelite -- -z -o $OUTPUT -n $NAME -s $LMS -a $ALSA -b $BUFFER -D
echo "Stopping Squeezelite"
start-stop-daemon -K --name squeezelite
echo "Usage: /etc/init.d/squeezelite {start|stop}"
exit 1

Save the file and:

sudo chmod +x /etc/init.d/squeezelite
sudo chown root:root /etc/init.d/squeezelite
sudo update-rc.d squeezelite defaults
sudo update-rc.d squeezelite enable

P.S. Please pay attention when you set the scheduler and the niceness; if you don’t know what are you doing remove “-N $NICENESS -P $SCHEDULER” from the script. If you have any question about this init script ask your questions in the comments below.

Automator (macOS)

Coming soon …

Batch script (Windows)

Coming soon …