My range improved dramatically studying Linklater as an actor. Freeing The Natural Voice. It's not for everyone, but if you can grasp it and consistently practice, you can reach new depths vocally & frankly, emotionally. It's a technique many stage actors have studied.
One book that I learned a lot from was Kristen Linklater's "Freeing the Natural Voice". If you can pick up a copy from Amazon or something, it's so worth it. There's lots of useful techniques and exercises for getting down in your gut even if your natural inclination is to be restricted to your upper level. She talks a lot about the core and nature of animals to make noise from their gut.
Link to her Wikipedia page if you want to learn more about her
Give it a try :) If it doesn't work for you, there are plenty of voice coaches out there who would charge a reasonable fee to get you where you want to be.
Thank you, but I'm looking for the audiobook, not the podcast.
https://www.amazon.ca/gp/product/0896762505 - This is what it looks like.
The audiobook was available just a couple of days ago on Audible.
https://www.amazon.com/Freeing-Natural-Voice-Practice-Language/dp/0896762505
Best book/method out there for voice and breath for actors.
Vocal training really does wonders. I was a theater major for a while, and took a voice and diction class. Really enunciating your words and speaking with confidence makes a big difference. I also learned that my voice was very nasally, and the exercises really helped me speak from my throat and not my nose. I've found it to be really helpful in my life. When I worked as a receptionist, I was constantly complimented on my voice, especially over the phone. I also feel it helps me stand out because I'm not slurring my words together. It also helps you sound more pleasant, which is nice. This is the book we read. We also learned timing, so that you have enough breath to say what you need to say without taking unnecessary breath-breaks. You might feel silly doing the exercises, but they really do work! It's also a great resource if you speak in front of groups.