Radsone ES100 by Jules
I listen to a lot of HiRes files..(96k, 88.2k, 192k 24bit)
Very disappointingly iPhone wont do HiRes playback...
(its capped at 48k unless you use a 3rd party converter - and then you have to jump through hoops and have to run it via a lightning to USB2 camera adapter to micro USB - to your converter)
...so I use a Digital Audio Player (DAP) to play back & stream HiRes files. I am using a FiiO M9.
I have a few albums in flac format on a 400 gig Micro SD card but the majority of my HiRes tracks are "Offline Downloads" from Qobuz (an upmarket Spotify like product) subscription Qobuz - High quality music - Unlimited streaming and Hi-Res download store . You can also do this sort of HiRes download via TIDAL's MQA (Master Quality Authenticated) subscription. TIDAL MASTERS – TIDAL
What I want from walking around listening to audio.
1) HiRes audio (Qobuz subscription)
2) Noise isolation (from traffic and public transport while commuting)
3) Hands free (lack of cables to get snagged)
4) EQ to tweak the overall system sound
5) Ability to "multi pair" a DAP and my phone so I can accept phone calls.
ES100 allows me to do 3, 4 & 5.
I am a big fan of the LDAC bluetooth codec developed by Sony. it transmits at 3x regular (SBC) bluetooth and
'nearly' transmits all the 96k 24bit audio. It sounds WAY better than regular bluetooth and is a step above AtpX HD in sound quality.
Enter the Radsone "EarStudio" ES100 bluetooth LDAC receiver / headphone amplifier.
Its smaller and lighter than a box of matches. (See how tiny it is in the photos below) It has 3.5 mm regular headphone socket and a 2.5mm balanced socket.
I output LDAC bluetooth from my FiiO M9 player and have my headphones (Etymotic ER4-XR) plugged into the ES100 via a short cable - then keep the ES100 in my shirt / jacket pocket or clipped to my coat collar. This way I can get the DAP out and select tracks without cables pulling at my ears or getting caught up in jacket zippers.
The sound quality of this headphone amp is AMAZING IMHO. Especially for its size.
It has a companion iPhone app that you can tweak with, 10 band eq, 4 custom presets, 22 eq presets, various digital filters.
So I have eq presets saved for
My Etymotic ER4-XR in ear monitors
My Bose QC20 noise cancelling ear buds
My Bluetooth speaker (for kitchen / shower etc)
In my car I use the cigarette lighter to power my iPhone, and plug the ES100 into the AUX input. I run Waze Sat Nav app & listen to podcasts. The Waze app voice directions and podcasts get transmitted to the car audio system via bluetooth ES100. The directions 'interrupt' the podcasts.
Using a custom eq curve preset I tweaked for my portable speaker turns its normally crappy sound into something bearable to listen to. (i plug the ES100 into the speakers 3.5mm Aux input)
The custom tweaks for the Etymotic and QC20 earphones help them sound as near perfect as I can get. I use songs I know really well to set the EQ curves up.
I even have the L/R balance skewed to the left a Db or so to match my hearing..
The rechargeable battery in it seems to last a long time.. All day easily..
It even survived a few seconds submersion in a toilet bowl
So I would recommend this for:
Car audio playback
Portable headphone playback
Ability to LDAC bluetooth transmit to a home stereo or portable speaker
(It also works with AAC bluetooth which is the highest quality the iPhone can output)
I think it's a wonder gadget!