Port fortification question

[SLM]

Last year I made a blackberry port. I started with 14% ABV wine and brought it up to 18% with cognac. It is delicious.
This year I decided to keep step feeding sugar until I reached 19% (if I measured right). My question is, How much flavor is imparted by the spirit? I plan to experiment a bit with ABV. I want to know how it tastes without fortification, with cheap brandy, and with good cognac. But it will be several months before I can form a fair conclusion. So if anyone has experience in this regard, please share.

 

[Boatboy24]

I've only used Brandy in the past, so I can't speak to the Cognac. But in my experience, not a huge amount of flavor comes from the spirit. Assuming you plan on doing bench trials, I'd say that's the best way to determine what works for you.

 

[Vinobeau]

I did it once with Cognac and it is terrible. The Cognac flavor took over! I would stick to cheap Brandy.

 

[winemaker81]

A decent cognac will flavor the result, depending on how much is used. This is a variable target, so it's impossible to provide good advice.

 

[NorCal]

I too have only added Brandy from Costco, never disappointed.