Hey Coleman and other learners, I would like to ask how to pronounce the consonant gb in Maninka as in words like gbɛlɛn (difficult) or gbɛ (white), for example tips on where should I put the tongue, what shape should I keep my lips or the nature of the sound.
I ask because this sound doesn‘t seem to exsit in the languages I speak (Chinese, English and French) and my Guinean friend says I confuse it with the b sound or the nasal ng sound.
Ai ni ke!!
I ni ke, Forrest! Good question!
The consonant /gb/ in Maninka is a “labio-velar” consonant meaning that it is both the labial sound “b” and the velar sound “g” at the same time. (Another one exists in some Manding varieties and other West African languages too: /kp/, so the term is not just for /gb/.)
Many people that natively speak language without labio-velars have a hard time hearing and pronouncing /gb/ correctly. As you note, many English and French speakers hear it as a “b” sound. (Take for instance the way that French people pronounce the former Ivoirian president Laurent Gbagbo’s last name: [bag-bo].) But that’s not it!
You really need to focus on doing a “b” and a “g” at the same time.
I would recommend starting with the sound of a “g” like in the English word “gay”. Say it a few times and then try to focus on saying it while also trying to flatly close your lips (that is, closing them like you have to when you say a “b” in English). The trick is that you want to “g” and “b” to fire/release at the same time. If you practice enough, you’ll hopefully start to sound like you are pronouncing something like gbɛ ‘white’ in Maninka.
If you have trouble pronouncing gb (or people keep thinking that you are saying b), it is best to use an entirely different strategy: say gw or even g in its place.
This lines up with the practice of Bambara and Jula speakers. The sound and spelling gb does not exist in Bambara. Its equivalent is generally g or gw. For instance, gbɛlɛn VS gɛlɛn/gwɛlɛn ‘difficult’.
In some cases, the Maninka gb corresponds with other sounds in Bambara/Jula:
gbɛ→jɛ‘white’
gbolo→wolo‘skin’
But it never becomes “b”. That’s why you need to avoid that pronunciation at all costs.
Let me know if that helps!
PS - Maybe I can try to do a video about this topic as well! Can you post in Suggest a video / Suggérer une vidéo so that I remember? 
Thank you so much Coleman for such a detailed answer! I will try practice with the tips suggested.