Knocking noise

So does it sound like the engine knocking?Or a different kind of noise?

What and where does it sound like it's coming from?

Noise's are hard enough to find in person test driving the car let alone over the internet. So have you pulled your transmission dipstick to see if the fluid is low or looks like there is material in the fluid like something is coming apart in your transmission?Is that the only time you hear the noise is while driving and the rpm's are ready to shift?

I would double check that transmission fluid most manual transmissions the fluid get's over looked and most don't have a dipstick so there rarely checked when checking the fluid. The only way I can tell you to try to track down the noise for sure is to put the front of the car on jack stands securely and block the wheel's with the brake on. Then spin the front wheel's until you hear the noise use a long screwdriver up to your ear while touching different part's of the car like transmission engine etc. To track the noise down.