Radsone EarStudio ES100
Mar 6, 2018 at 3:57 AM Post #331 of 6,673
All,

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

[Test condition]
- No load
- AK4375a / sharp roll-off / 1x

aptX (with Galaxy S8 source device)


USB (lossless, with iMAC USB)


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
In my particular case, I have horrible aliasing and clipping of sound that I can hear in the normal music with SE846.
I guess I'm the only one yet who used it with high-resolution low impedance earpieces.
And they should work if you have 0.5Ohm claimed OI.

Let's go through your points:

I never insisted (moreover I hope for the opposite) that it's design or H/W issue. So, that's not true.

THD+N doesn't show aliasing or clipping. I already know it from RMAA. And you choose to measure only this by showing exactly same figures I got from RMAA.
It is NOT some kind of ultimate test that shows there is no issue at all. You intentionally not addressing the issue I'm talking about and instead post charts that are masking issue.

Issue decreases without load - exactly what you have done - you removed any load (well, because it's easier - why bother to put any work on your product...).
I assumed that oversampling might be bringing issue - and you turned it off in your tests.

I already have shown that dirt cheap APTX receivers do not exhibit aliasing or clipping at such levels as your product.

Bringing names of Qualcomm is NOT answering the issue I have - you do not search for the issue at all.
A company that you paid for certification is not certifying your product claims.
Reviewers that you asked to do review did no measurements or synthetic tests at all and we have no idea if they were even paid or not (and from my experience - that's how they make money).
You have few people here who ok with what they got. And you have 1 who is not.

Meanwhile: this is the test I'm asking to do by those who have 16Ohm and below earphones on EarStudio:
http://www.audiocheck.net/audiotests_mosquito.php "Mosquito Tone 2" test on this page - set normal maximum volume and run it - if you hear anything clearly - you should not be. Check with and without oversampling.
I can barely hear anything from Nokia and I hear plenty off-tones and grinding noise from ES.
And that is clear indication that it should not be like that - it's not a codec inherent issue.
 
Last edited by a moderator:
Mar 6, 2018 at 7:22 AM Post #333 of 6,673
Mar 6, 2018 at 10:13 AM Post #334 of 6,673
We've had to clean up some of the recent conversation in this thread. We ask that everyone please keep their posts within the posting guidelines. Let's please keep our posts related to the Radsone Earstudio rather than going off topic and/or getting personal with our comments. Thanks for the assistance everyone, we really appreciate it.
 
Mar 6, 2018 at 10:26 AM Post #335 of 6,673
Using the es100 now, no issues with noise etc. With aptxhd it sounds better than with my LG g6 with quad dac
I like to hear this, mine is on the way from Radsone warehouse in LA and I can't wait to hear it paired with my lg g6 over aptx hd. Does the g6 let you choose the codec or does it default to aptx hd and does it indicate what the connection is? Also are the volume controls locked together or do they act independently? Right now my g6 and Sony sbh50s volumes are locked together but my note 4s volume works independently of the sbh50.
 
Mar 6, 2018 at 10:50 AM Post #336 of 6,673
Could anyone who has one of these things tell me the shipping dimensions of the package as it came? Thinking of using a service like borderlinx or similar to get one ahead of the UK launch..
 
Mar 6, 2018 at 11:09 AM Post #337 of 6,673
Could anyone who has one of these things tell me the shipping dimensions of the package as it came? Thinking of using a service like borderlinx or similar to get one ahead of the UK launch..

Tiny. A small paper box in a padded envelope. Volumetric weight, as determined by my freight forwarder, was 0.2kg. Actual weight was 0.1kg.
 
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Mar 6, 2018 at 11:19 AM Post #338 of 6,673
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)


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)


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)


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

Is there any way to plot spectrograms instead of spectrums, and with a sweep tone? With spectrums, the frequency plot is averaged out over a long time, so transient effects are not as apparent. This is especially the case when the frequency is constant (like in your current plots).

If you play a swept tone, and plot the spectrogram, which shows how the frequency changes over time, it will be easier to see at what point harmonics and transients begin to appear (if there are any).

Also: When I use the Earstudio's USB DAC mode on my Windows computer, I cannot change the sampling rate from 48kHz. Since most of my audio is at 44.1kHz, I'd prefer that the DAC matches my input. Is there any way to change this?
 
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Mar 6, 2018 at 12:24 PM Post #339 of 6,673
So I've got one more source of APTX sound (which also got APTX LL) to play directly from the computer without any excessive conversions - http://www.avantree.com/bluetooth-audio-transmitter-avantree-priva-iii.html
Also got my 2.5mm balanced wire for HD650 (300 Ohm). Running Mosquito test makes a lot less cracking noise - like 5-10 pops/second instead of 100-200, but it's there and unfortunately, it's full volume.
If I play music together with Mosquito test - it becomes A LOT of cracking noise. Not sure if I changed anything in the settings, though.

I'm waiting for my 3.5mm socket splitter to make spectral with headphones in parallel. That also would allow me to do proper recording of actual sound to share.
P.S. Thanks to @AxelCloris for cleaning drama.
 
Mar 6, 2018 at 12:51 PM Post #340 of 6,673
I just received my ES100, and I probably shouldn't say this without spending more time with it, but it's awesome :)

Also: When I use the Earstudio's USB DAC mode on my Windows computer, I cannot change the sampling rate from 48kHz. Since most of my audio is at 44.1kHz, I'd prefer that the DAC matches my input. Is there any way to change this?

I managed to get the ES100 working as a usb dac on my windows 7 laptop, when using streaming programs such as Tidal (not HiRes), and it's coming across to the ES100 as 16bit/48khz. Sounds good to me.

But when trying to play a flac tune (16bit/44.1khz) though foobar 2000 I'm getting "Unrecoverable playback error: Unsupported stream format: 44100 Hz / 16-bit / 2 channels". Maybe there's a simple setup or configuration change I need to make somewhere, but if anyone has any suggestions I'm all ears!
 
Mar 6, 2018 at 1:08 PM Post #341 of 6,673
@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

only in that aliasing test. I am not tester, I listen to music with ldac. Probably no problem with music unless you have bat ears.
 
Mar 6, 2018 at 1:09 PM Post #342 of 6,673
I guess I'm the only one yet who used it with high-resolution low impedance earpieces.

Nope.
I use Spiral Ears 5 Ultimate - they should be around 15-25 Ohm too.
But ATM i can only use it with AAC from my iPhoneX. (not at home for a few weeks)
And there everything sounds as i think it should. - And i think i have (still) a decent hearing. At least i can differentiate between very poor and good cables.

But as i wan't to go for a Android device (with APTX HD) by the end of the year i'm very interested in the results of this discussion :wink:
 
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Mar 6, 2018 at 1:36 PM Post #344 of 6,673
In my particular case, I have horrible aliasing and clipping of sound that I can hear in the normal music with SE846.
I guess I'm the only one yet who used it with high-resolution low impedance earpieces.
And they should work if you have 0.5Ohm claimed OI.

Let's go through your points:

I never insisted (moreover I hope for the opposite) that it's design or H/W issue. So, that's not true.

THD+N doesn't show aliasing or clipping. I already know it from RMAA. And you choose to measure only this by showing exactly same figures I got from RMAA.
It is NOT some kind of ultimate test that shows there is no issue at all. You intentionally not addressing the issue I'm talking about and instead post charts that are masking issue.

Issue decreases without load - exactly what you have done - you removed any load (well, because it's easier - why bother to put any work on your product...).
I assumed that oversampling might be bringing issue - and you turned it off in your tests.

I already have shown that dirt cheap APTX receivers do not exhibit aliasing or clipping at such levels as your product.

Bringing names of Qualcomm is NOT answering the issue I have - you do not search for the issue at all.
A company that you paid for certification is not certifying your product claims.
Reviewers that you asked to do review did no measurements or synthetic tests at all and we have no idea if they were even paid or not (and from my experience - that's how they make money).
You have few people here who ok with what they got. And you have 1 who is not.

Meanwhile: this is the test I'm asking to do by those who have 16Ohm and below earphones on EarStudio:
http://www.audiocheck.net/audiotests_mosquito.php "Mosquito Tone 2" test on this page - set normal maximum volume and run it - if you hear anything clearly - you should not be. Check with and without oversampling.
I can barely hear anything from Nokia and I hear plenty off-tones and grinding noise from ES.
And that is clear indication that it should not be like that - it's not a codec inherent issue.

I don’t have one but I can hear the tones above using my stuff so not sure what’s that proving? Even at fairly low volumes.
 
Mar 6, 2018 at 1:37 PM Post #345 of 6,673
So I have found an interesting thing - my USB APTXHD source from Avantree also stupidly locked at 48kHz, thank you very much, but it's seems to be the actual reason that with it I don't have such horrible clipping.
Aliasing is still there (and it shouldn't be), but it's not loud and cracking is not high.

I can get significantly stronger cracking with that position if in EQ I would push 16k above +9dB. And aliasing starts to ring full volume if it's +10dB. And it sounds then same as with 44.1.
I'm sure that I've checked EQ off on all my tests, but I have to go back to 44.1 on low impedance and recheck it again tomorrow.

But when trying to play a flac tune (16bit/44.1khz) though foobar 2000 I'm getting "Unrecoverable playback error: Unsupported stream format: 44100 Hz / 16-bit / 2 channels". Maybe there's a simple setup or configuration change I need to make somewhere, but if anyone has any suggestions I'm all ears!
You have to use foobar plugin to change a frequency of audio to 48kHz.

Also: When I use the Earstudio's USB DAC mode on my Windows computer, I cannot change the sampling rate from 48kHz. Since most of my audio is at 44.1kHz, I'd prefer that the DAC matches my input. Is there any way to change this?
Maybe it's USB Audio class 1 limitations (Edit: NO, Class 1 is up to 24 bit 96kHz)

I use Spiral Ears 5 Ultimate - they should be around 15-25 Ohm too.
16 would be relatively standard. Mines are 9Ohm and 4 armature, so it's a hell for any amp.

I don’t have one but I can hear the tones above using my stuff so not sure what’s that proving? Even at fairly low volumes.
If you can hear running tones - it's aliasing. It's not supposed to be there (unless you pass blind test for above 17kHz). Aliasing is quite common in regular equipment. But it should not be part of HiFi and there are APTX receivers that don't have it. Plus in my case it's heavily overloaded - it's pretty much at 0dB volume - off-tones and cracks.
 
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