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Topping BC3 Review (Bluetooth Receiver) & BT CODECs

PeteL

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Interesting. I know android and iOS do some compensation for delay but it is news to me that computers do that too.

Do you know if it's OS dependent or application dependent specifically regarding Windows 10?
I have to admit I havent tested this with Windows lately, I use MacOS for my Bluetooth setup, but If I have time I'll check, I don't want to confirm without being 100% sure but why wouldn't they? I'm not sure of the full mechanics of this but I feel it might be more than just OS, because in my experience, It took longer to get it right with Youtube than anything else, for a long time Netflix was in sync and not Youtube, but now for my use case it's across the board.
 

Overseas

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Anybody confirming they have a stable LDAC 990 connection with a Huawei phone ? What distance ?
Looking to invest in a BC3.
I do not ask what is the perceived difference with Aptx Hd cause probably it is subjective.
 

Nathan Raymond

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Interesting. I know android and iOS do some compensation for delay but it is news to me that computers do that too.

Do you know if it's OS dependent or application dependent specifically regarding Windows 10?

It is called "Delay Reporting" and it is part of the AVDTP 1.3 (Audio/Video Distribution Transport Protocol) user profile. As stated here, Windows 10 (Version 1903) supports Bluetooth 5.0 and AVDTP 1.3:

https://support.microsoft.com/en-us...profiles-8900e50f-318e-4283-2beb-c8325bfc9515

As stated here, it is supported by Android 9+ and Linux with PulseAudio 12.0+:

https://sudonull.com/post/38257-Audio-via-Bluetooth-maximize-details-on-profiles-codecs-and-devices

I imagine recent iOS and macOS support it as well, my quick search didn't turned anything up specific, but I didn't spend much time looking.
 

AndreaT

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I received mine. LDAC encoding from Hidizs AP80. Volume button must work only with headphone output, and not with digital out, right? It is actually explained in the manual as: "Uncontrollable volume during Optical output"...:)

Sound quality from FLAC 44.1/16 LDAC 24 bit (at least this is the led that lights up on my Benchmark DX3) most excellent. I am not impressed with the range: I must have a radioactive body because if I stand between the Hidzs and the BC3 signal has brief drops out.

The previous, injudiciously bought, BT receiver Auris BlueMe w AptX is not even comparable, and it was more expensive.
Thank you Amir!
 

danny87

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Hi all. I'm deciding between the Topping BC3 and the iFi Zen Blue, and will be using mainly the optical out, so I'm not too concerned on the DAC or amp portion. Looking at the Bluetooth chipset, iFi is using the newer QCC5100 chipset for the Bluetooth decoding, while the Topping BC3 is using the previous gen CSR8675. The only significant difference i can see is that the newer QCC5100 uses less power, which doesn't really matter since the iFi is not a portable unit.

Other than that it seems the QCC5100 has higher processing power, but does this translate to better audio quality?

Appreciate any advice. Thanks!
 

Mulder

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And can we hear the difference from lossless? I have a couple of Topping DACs around the place, a DX3 Pro and a D-50s. Both are often fed over bluetooth simply because it is convenient. I might stream from a phone, feeding a pair of powered monitors in the workshop and so on. Even the bedroom system. WiFi means more messing and usually an additional box.
Whilst the traditional audiophile OCD always wants lossless, it remains to be shown that in all bar the most critical of listening environemnts that there is any downside to these lossy codecs. I am very suspicious the answer is a flat "no". Indeed even in critical environments I bet the answer is usually "no".
It seems like people can´t distinguish between for example AAC and uncompressed WAV. Since AAC is a perceptual audio coder, I wonder if it is comparable to the other bluetooth codecs here in the way they are measured here? https://www.hindawi.com/journals/ijdmb/2019/8265301/
 

Mulder

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Went back to basics by just encoding some 1 kHz tones in AAC and examining them on the computer. Tested both with 24-bit test signal that I used here and 16 bits:

View attachment 132514

I held AAC to higher regard!
May I ask which AAC encoder you used here? Was it Apple's encoder, or was it another? Maybe Fraunhofer FDK AAC. Since I use the iPhone, I have taken a closer look at this, and many seem to think that AAC encoded with Apple encoders gives better results than other encoders.
 

Kosta

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Hi looking to get this to enable Bluetooth on my K5 Pro so just some (probably stupid) questions:
If connect this with toslink then :
- am I bypassing the DAC on the K5 and just using the headphone amplifier section ?
- which volume controls would be active BC3, K5 Pro , Mobile phone (all of the above)
- (assuming LDAC & CD quality source) Sound quality wise from the measurements it looks like I wouldn't be degrading my current K5 Pro experience ?
 

infinitesymphony

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Hi looking to get this to enable Bluetooth on my K5 Pro so just some (probably stupid) questions:
If connect this with toslink then :
- am I bypassing the DAC on the K5 and just using the headphone amplifier section ?
- which volume controls would be active BC3, K5 Pro , Mobile phone (all of the above)
- (assuming LDAC & CD quality source) Sound quality wise from the measurements it looks like I wouldn't be degrading my current K5 Pro experience ?
To answer your last question first, Bluetooth does not currently have a true lossless option, so any use of Bluetooth will create a lossy conversion of your original lossless files. In a technical sense it will no longer be CD quality. Whether or not that's audible is a different question.

It sounds like this will be your signal path:

Phone ---[BT]---> Topping BC3 ---[optical]---> K5 Pro

In this scenario the K5 Pro will be handling DAC and headphone amp duties because the stream will be digital until that point.

If you want to use the BC3's DAC, you will need to connect its line output to analog inputs:

Phone ---[BT]---> Topping BC3 ---[3.5mm line output - 2 RCA line input]---> K5 Pro
 

danny87

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Hi looking to get this to enable Bluetooth on my K5 Pro so just some (probably stupid) questions:
If connect this with toslink then :
- am I bypassing the DAC on the K5 and just using the headphone amplifier section ?
- which volume controls would be active BC3, K5 Pro , Mobile phone (all of the above)
- (assuming LDAC & CD quality source) Sound quality wise from the measurements it looks like I wouldn't be degrading my current K5 Pro experience ?
1. If connecting with Toslink, the digital signal will need to go to K5's DAC. You are only bypassing DAC on the Topping BC3.
2. Volume control on BC3 is disabled via Toslink output. Will be set to max. You can control volume via K5. Control via phone likely not possible.
3. Unlikely to be noticeable.
 

Kosta

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To answer your last question first, Bluetooth does not currently have a true lossless option, so any use of Bluetooth will create a lossy conversion of your original lossless files. In a technical sense it will no longer be CD quality. Whether or not that's audible is a different question.

It sounds like this will be your signal path:

Phone ---[BT]---> Topping BC3 ---[optical]---> K5 Pro

In this scenario the K5 Pro will be handling DAC and headphone amp duties because the stream will be digital until that point.

If you want to use the BC3's DAC, you will need to connect its line output to analog inputs:

Phone ---[BT]---> Topping BC3 ---[3.5mm line output - 2 RCA line input]---> K5 Pro
Thank you. As a side note I noticed that my Android phone connects as a "wired headset" via USB to the K5 so am I bypassing the phone processing the audio? I can change the volume through the phone too
 
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infinitesymphony

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Thank you. As a side note I noticed that my Android phone connects as a "wired headset" via USB to the K5 so am I bypassing the phone processing the audio? I can change the volume through the phone too
Yes, that should be the case, although the ability to output bit-perfect audio over USB OTG may depend on your Android OS version, playback app, and the bit-depth and sampling rate of your source material. Some say Android historically has downsampled to 16-bit/44.1KHz.

Use the volume control on the K5 Pro for the best results unless you can guarantee the phone's digital volume control isn't truncating bits and reducing quality, otherwise do whatever is most convenient. None of my BT setups are for critical listening, so I just end up changing the volume at the closest device.
 

Mulder

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In my experience, LDAC is not reliable. At least not if the highest quality is sought. I have exactly the same mobile as amirm has in the test, but it hacks and hangs. If you are going to use bluetooth, it is aptX and AAC that is sufficiently reliable, at least in my experience, and then it is probably more doubtful if we can talk about real HiFi.
 
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Kosta

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***update ***
Turns out the K5 pro only accepts 44.1 on optical. Trap for young players


Hi , looking for some help. Just got the Bc3 , using with K5pro. However the toslink connection is not working. There is no sound. Tested Bc3 headphone out OK. Tested line out OK. I can see the red light coming out of the optical connection so something is getting through. I tested the optical in of the K5 using the TV as a source all OK.
Anybody else have similar issues ? is it time to return back to shenzhenaudio ? Would be a shame because is looks like a great little device.
 
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Atanasi

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I am unable to charge BC3 with a USB-C charger connected with a C-C cable. The charging light wouldn't turn on. If BC3 is connected with a C-A cable, charging works. The difference between these cables is that a C-A cable always has the voltage activated, whereas a C-C cable doesn't turn on the voltage before negotiation, this is to support dual-role ports.
I suspect BC3 doesn't have correct CC pin terminations to negotiate charging voltage, so it is not USB-C compliant.
 

Grur

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talking of charging, if you leave the BC3 plugged in, for home use, does it stop charging in order to preserve the longevity of the battery? Assuming the battery is non-replaceable, that is?
 

dorirod

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Does setting the Bluetooth sample rate matter for either quality or performance? For example if music is 44.1, would it matter if BT is 44.1, 48, 96, etc?

Thanks
 

Atanasi

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It's the same as any other signal chain: if the sample rates don't match, the sound is resampled. If the implementation is good, there shouldn't be audible artifacts (distortion less than -130 dB level), but cheaper implementations have more artifacts.
 

Yasser 06

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Could you test the budget receiver / transmitters from china, as example the vikefon here : https://fr.aliexpress.com/item/1005...exp_id=307e3f47-5ef1-412d-ae9a-437f335f78e8-4

It has 2 antenna and use a CSR8675 as BT chip.

It is dirty cheap (25 euros).

It is convenient since it can send and receive, so i can listen to my phone or send the music from my dac to my earbud or my shanling up4.

It is 1/4 of the price of the fiio BTA30 so there is probably a huge difference, but since i use it mostly with wireless headphone or the shanling the receiver and the codec have enough loss so that i don't really ear any difference between the 100 dollars fiio and the 30 dollars vikefon. Morever the fiio had lesser range and could only transmit, so i returned it.
 
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