Radsone EarStudio ES100
post-14084752
Post #316 of 6,351

veraideishal

New Head-Fier
Joined
Mar 26, 2016
Messages
44
Reaction score
35
Joined
Mar 26, 2016
Posts
44
Likes
35
I need to repeat AAC test yet - still doing RMAA on Nokia for reference.

Digital volume was set to 0dB, for sure - that was first question support has asked me and I studied docs well before using it. I tried to change all settings - nothing removes clipping or aliasing. Now I have to say - APTX on Nokia also sandy, BUT it's so low level that I have to crank up the volume really high. While on EarStudio it's extremely loud.

I have 2$ USB sound card - it also has aliasing doesn't matter which signal or what setting are sent - I assume it's frequency conversion with bad rounding.

We already eliminated source - Nokia on exactly same source doesn't make any aliasing and clipping is way below the level of importance.
I think the problem with the USB sound card is different from the problem with the Earstudio. On the USB sound card, it takes in uncompressed PCM data and outputs a voltage. If there is any aliasing, it's due to only that process (PCM to voltage, possibly due to bad rounding and a lousy anti-aliasing filter).

With the Earstudio, if AAC (and the USB DAC output, if that gets tested) show no problems, then it is not the PCM to voltage conversion that is to blame (testing the USB DAC mode of the Earstudio is probably the best way to confirm this, since it is taking in PCM data directly).
The problem then lies with the Decoder, which takes in either compressed SBC and aptX and converts to PCM. There is likely to be more problems that result from the decompression process.

I don't really care that much about returning. I can afford to lose 300$ without ruining my mood. It's a Kickstarter purchase - it's meant to support new companies that propose good ideas. But I thought I would help guys to find and fix a problem and found out that they don't care?... So I assume some people here might care still and somebody could be really frustrated in mine place.

I still would like to hear feedback from WS...
WS is probably asleep; it's the middle of the night in Korea.
 
Last edited:
     Share This Post       
  • Like
Reactions: wslee
post-14084764
Post #317 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
I think the problem with the USB sound card is different from the problem with the Earstudio. On the USB sound card, it takes in uncompressed PCM data and outputs a voltage. If there is any aliasing, it's due to only that process (PCM to voltage, possibly due to bad rounding and a lousy anti-aliasing filter).

With the Earstudio, if AAC (and the USB DAC output, if that gets tested) show no problems, then it is not the PCM to voltage conversion that is to blame (testing the USB DAC mode of the Earstudio is probably the best way to confirm this, since it is taking in PCM data directly).
The problem then lies with the Decoder, which takes in either compressed SBC and aptX and converts to PCM. There is likely to be more problems that result from the decompression process.

WS is probably asleep; it's the middle of the night in Korea.
I still need to test AAC properly. I don't remember now. I will test USB DAC also for sure.
 
     Share This Post       
post-14084765
Post #318 of 6,351

antdroid

Headphoneus Supremus
Joined
Jul 31, 2016
Messages
2,036
Reaction score
3,641
Location
Seattle
Joined
Jul 31, 2016
Location
Seattle
Posts
2,036
Likes
3,641
Website
www.audiodiscourse.com
I don't really care that much about returning. I can afford to lose 300$ without ruining my mood. It's a Kickstarter purchase - it's meant to support new companies that propose good ideas. But I thought I would help guys to find and fix a problem and found out that they don't care?... So I assume some people here might care still and somebody could be really frustrated in mine place.

I still would like to hear feedback from WS...
I cant try out your test right now. I have pretty weak LTE coverage at my office and also the phone mic picks up a ton of ambient noise. I dont know how accurate it would be.

That said, are you hearing audible issues using apt-x with actual music/videos or just the test?

I just listened to a couple songs and switched back and forth between SBC, AAC, Apt-X and AptX HD and i dont hear any clipping or any issues of note.
 
     Share This Post       
  • Like
Reactions: wslee
post-14084847
Post #319 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
I cant try out your test right now. I have pretty weak LTE coverage at my office and also the phone mic picks up a ton of ambient noise. I dont know how accurate it would be.

That said, are you hearing audible issues using apt-x with actual music/videos or just the test?

I just listened to a couple songs and switched back and forth between SBC, AAC, Apt-X and AptX HD and i dont hear any clipping or any issues of note.
Ambient noise doesn't matter - if headphone will be at the microphone - it will overpower everything - you can see signal pattern.
I started searching for the issue with Lana Del Rey and Soulsavers songs - on a high pitch clean tones I can clearly hear clipping.
Btw, since I have 3 devices - I've tried them all.
 
     Share This Post       
post-14084856
Post #320 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
Some update - I tried AAC from iPhone X. RMAA for it is really bad. And, btw, I found out RMAA doesn't catch this issue well - I will post it later. But - there is NO aliasing or clipping on AAC on EarStudio although sound is not very sharp (and RMAA confirms it), but it's consistent. Look at those. So issue is with SBC/APTX encoders.



Compare it with APTX on EarStudio:


And here is AAC 17.4kHz tone - a lot of smooth harmonics.


Still need to finish USB DAC
 
Last edited:
     Share This Post       
post-14084930
Post #321 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
USB DAC can't test today - there is -70dBA Noise Level which obviously is a ground loop.

I need to think how to remove it tomorrow. It's midnight for me as well.

I also probably need to redo the whole RMAA - it was on the 10kHz limit for THD.
 
     Share This Post       
post-14085654
Post #322 of 6,351

RobinFood

500+ Head-Fier
Joined
Dec 4, 2017
Messages
642
Reaction score
495
Location
Japan
Joined
Dec 4, 2017
Location
Japan
Posts
642
Likes
495
Is there a way to get an earstudio in Japan? Amazon US and Canada won't ship here, and I can't find any resellers on ebay or aliexpress either.

I need some kind of clip-on with bluetooth for my er4 when commuting, and was thinking of this as a solution that can keep the sound quality and let me take out the PtoS adapter.
 
     Share This Post       
post-14086058
Post #323 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
Got THD+Noise for all modes in EarStudio without ground loop issue. Noise in USB is unusually high.
 
     Share This Post       
post-14086297
Post #324 of 6,351

wslee

Member of the Trade: Qudelix
Joined
Dec 25, 2012
Messages
176
Reaction score
301
Location
Seoul, Korea
Joined
Dec 25, 2012
Location
Seoul, Korea
Posts
176
Likes
301
All,

I'd like to share some ES100 data measured using Audio Precision 2722 right next to my desk.

[Test condition]
- ES100 3.5mm output
- No load
- EQ, DCT off
- AK4375a / sharp roll-off / 1x

aptX (with Galaxy S8 source device)
upload_2018-3-6_14-58-38.png


It's just a lossy waveform codec using no psychoacoustic model.
It uses QMF(Quadrature mirror filter) to split the input into a certain number of sub bands.
And then it encodes each sub band with the limited bit allocation;
more bits in the lower frequency band, less bit in the higher frequency band.

SBC(SubBand Codec) also split the input into sub bands, but it allocates the same number of bits per for all sub bands.
That's the one of the main difference between SBC and aptX.

SBC is a very simple codec with low complexity.
The low complexity nature was the primary reason for having SBC as mandate Bluetooth A2DP codec.

And CSR released the new codec aptX with the key idea of allocating the different number of bits per each subband;
more bits in the lower frequency band, less bit in the higher frequency band.

So typical frequency response of a single tone would be as above.
The noise floor is not flat across frequency ranges because the quantization noise from aptX codec loss makes the floor.
aptX-HD performs better but the frequency response is similar to aptX classic.

AAC (with iOS)
upload_2018-3-6_14-58-58.png


It's a complicated codec based on the psychoacoustic model.
As you see below, the 1KHz and 10KHz tone is not sharp but shaped like a tower or triangle.
The key idea of the psychoacoustic model is that;
the signal or noise below the shape(i.e., Masking Curve) is not audible and not critical.
Eventually we just need to allocate as less bit as possible for the target signal below the masking curve.

So, the codec like AAC using the psychoacoustic model requires frequency analysis, the masking curve calculation for the time-varying input continuously,
which cost a lot of processing power and power consumption.

Since it's not a waveform coder, measuring THD+N for the signal through AAC codec has no meaning.
Only perceptual domain performance would make sense.
Anyway, AAC is more complicated than mp3, showing the better perceptual performance than mp3 at the same bit rate.

USB (lossless, with iMAC USB)
upload_2018-3-6_14-59-26.png


It shows the baseline performance of ES100 HW.
Unfortunately, ES100 USB supports 16-bit only, the overall THD+N is limited by the 16-bit PCM (-96dB), not by H/W.

Please take a look at them all above.
You will find there's no such a design flaw or HW defect as SubMash insist.

If ES100 have any H/W issue, all the BT codecs, and USB would result in the same defect.
Because all of them use the same H/W resource including DSP, DAC, and Power.
SubMash mentioned AAC & USB sounds OK.
Then it's not an H/W issue.

And if we have the problem with aptX,
how could we have ES100 in the Qualcomm's official aptX product list?
They have their own qualification and certification process for aptX enabled products.
We sent ES100 to them for their testing and finally had ours on the list.

https://www.aptx.com/products/radsone-earstudio-es100-bluetooth-receiver-headphone-amplifier

Lastly, I just took a look at the SubMash test results and graphs from his mobile phone screenshot.
It seems that he ran the test with his mobile phone.
Anyway, as I see them, those results are showing the tremendous and unacceptable noise.
If those graphs are indeed real and represent ES100 output,
the sound would be considerably worse than the expected,
and everyone would definitely notice the defect right at the start.

We can't deceive many thousands of ES100 users.
The users are not fools and would notice the that much of conspicuous defect very easily.

Thanks and Regards,
WS
 
Last edited:
post-14086347
Post #325 of 6,351

myusernameislove

100+ Head-Fier
Joined
Jan 8, 2018
Messages
239
Reaction score
134
Location
cz
Joined
Jan 8, 2018
Location
cz
Posts
239
Likes
134
Anyone used it with aptx except me? Because I can't be alone who can hear those problems.

http://www.audiocheck.net/audiotests_aliasing.php

Try this and tell me you don't hear random clicking and sand noise together with heavy harmonics ringing and sweep tones going all wrong directions. My test show harmonics louder than tone on SBC and APTX. Hope it's firmware bug - it sounds like wrong frequency conversion..
I tried it with my Sony xPeria XZ1 BT5 smartphone and Audio Technica AT-PHA55BT receiver with SBC, AAC, Aptx, LDAC support (no AptxHD), and LDAC, AAC, SBC is fine, but with Aptx I hear some sand.

edit/ I also tried my phone with Inateck BR1006 receiver with SBC, AAC, Aptx, AptxHD. SBC and AAC is fine, but with Aptx and AptxHD I hear some sand again.

There is two times longer sand noise with Aptx then with AptxHD on Inateck. The length of sand noise with Aptx on Inateck and on AT is about the same. The sand noise appears twice (two peaks) at higher end of the spectrum.

I have also heard one or two clicks with both units and all codecs (even LDAC) but after I repeated the test the click was gone, so I guess it is OK. Yes, I tested LDAC in all priority modes.
 
Last edited:
     Share This Post       
  • Like
Reactions: bidn and wslee
post-14086367
Post #326 of 6,351

SubMash

100+ Head-Fier
Joined
Mar 4, 2018
Messages
294
Reaction score
120
Location
Prague
Joined
Mar 4, 2018
Location
Prague
Posts
294
Likes
120
I tried it with my Sony xPeria XZ1 BT5 smartphone and Audio Technica AT-PHA55BT receiver with SBC, AAC, Aptx, LDAC support (no AptxHD), and LDAC, AAC, SBC is fine, but with Aptx I hear sand.

edit/ I also tried my phone with Inateck BR1006 receiver with SBC, AAC, Aptx, AptxHD. SBC and AAC is fine, but with Aptx and AptxHD I hear sand.

There is two times longer sand noise with Aptx then with AptxHD on Intaeck. The length of sand noise with Aptx on Inateck and on AT is about the same. The sand noise appears twice (two peaks) at higher end of the spectrum.

I have also heard one or two clicks with both units and all codecs (even LDAC) but after I repeated the test the clicks stopped occuring, so I guess it is OK. Yes, I tested LDAC in all priority modes.
So problem not only sand. It plays in the beginning sound that is NOT the tone itself, but harmonics at the lower frequency instead. And you can understand it, because tone should go linearly down and if instead it's moving up/down or doing steps - it's not the tone you hear - it's garbage.
I can confirm that sand is everywhere, but with EarStudio it's way stronger - I have a suspicion that load + oversampling influences noise. I need to check it again.
 
     Share This Post       
post-14086368
Post #327 of 6,351

tim0chan

1000+ Head-Fier
Joined
Sep 28, 2016
Messages
1,400
Reaction score
732
Joined
Sep 28, 2016
Posts
1,400
Likes
732
Using the es100 now, no issues with noise etc. With aptxhd it sounds better than with my LG g6 with quad dac
 
     Share This Post       
  • Like
Reactions: scotvl and wslee
post-14086370
Post #328 of 6,351

wslee

Member of the Trade: Qudelix
Joined
Dec 25, 2012
Messages
176
Reaction score
301
Location
Seoul, Korea
Joined
Dec 25, 2012
Location
Seoul, Korea
Posts
176
Likes
301
I tried it with my Sony xPeria XZ1 BT5 smartphone and Audio Technica AT-PHA55BT receiver with SBC, AAC, Aptx, LDAC support (no AptxHD), and LDAC, AAC, SBC is fine, but with Aptx I hear some sand.

edit/ I also tried my phone with Inateck BR1006 receiver with SBC, AAC, Aptx, AptxHD. SBC and AAC is fine, but with Aptx and AptxHD I hear some sand again.

There is two times longer sand noise with Aptx then with AptxHD on Inateck. The length of sand noise with Aptx on Inateck and on AT is about the same. The sand noise appears twice (two peaks) at higher end of the spectrum.

I have also heard one or two clicks with both units and all codecs (even LDAC) but after I repeated the test the click was gone, so I guess it is OK. Yes, I tested LDAC in all priority modes.
@myusernameislove:
Can I ask the sand noise you're experience is with the test tones or sweeping chirp?
Just want to check if you hear the noise only with the test signal or also with regular music sources.
Thanks and Regards,
WS
 
     Share This Post       
post-14086382
Post #329 of 6,351

m4rkw

100+ Head-Fier
Joined
Oct 26, 2017
Messages
285
Reaction score
68
Location
London
Joined
Oct 26, 2017
Location
London
Posts
285
Likes
68
@wslee is there any update on UK sales? I was told on twitter that they would begin early this month.
 
     Share This Post       
post-14086395
Post #330 of 6,351

wslee

Member of the Trade: Qudelix
Joined
Dec 25, 2012
Messages
176
Reaction score
301
Location
Seoul, Korea
Joined
Dec 25, 2012
Location
Seoul, Korea
Posts
176
Likes
301
@wslee is there any update on UK sales? I was told on twitter that they would begin early this month.
@m4rkw, @PantsUK:

I'm so sorry we're still working on it but having some problem with the shipment to warehouse.
We'll open AMAZON Europe no later than the end of April.
Sorry and appreciate your patience.
WS
 
     Share This Post       

Users Who Are Viewing This Thread (Users: 0, Guests: 3)

Top