A while ago, I saw a tutorial/how-to on constructing a mini sound booth - not one isolating the speaker but one for isolating the microphone - it was foam constructed around the mic.
Can anyone point me to this - I would really appreciate it.
You might try accessing the Vasst.com website. I seem to remember reading the info there but I find it too much trouble to login and I'm rarely at the same PC each time I do. I appreciate it is a better user experience with the login approach. Try there in the free resources first. It was shown and made available publicly at one point in time as I recall.