Not all of the Spanish Brandy’s are nose pleasers. Not all of them are going down your throat like honey. There is a reason why the Spaniards say, Brandy tastes well from the second glass onwards.
Age and storage are certainly the biggest factors that smoothen out Brandy. Young Soleras miss the complexity and pleasing notes of the Solera Gran Reservas (the later clearly being in the focus of feltedhat). The alcohol is less noticeable the older a brandy (or its components) are. Brandy has its own taste universe unlike other spirits. You may like this or not of course. But to me, when somebody says that a Brandy is smooth it is one of the biggest compliments you can make.
Mind you not smooth like in the sense of weak. Brandy has to have a bit of punch and it does have to have some edges that often characterize the different batches. But when you feel a balance of appealing and/or signature tastes and aspects and it sums up to an intriguing construct that can be well enjoyed, this might be the smoothness that honors a Brandy, the royal drink.
Check my list of favorites Brandy’s. They all have that smoothness. That said of course there a lot more Brandy’s out there that have that too. This is a mere representative selection so you can go and search for this feature yourself. 🙂
Note that brandy gets smoother and lets say more pleasant in the nose when it is hand warm. This is not the same smoothness I am writing about here.