That's a good start, if you can slowly increase the amount of time to about an hour of exercises you'll see your voice grow even faster. If you look on @Klaus_T page, he has a list of the free YT videos Ken has that can be made into a workout.
@Wigs , I practice almost every day, only missing one day about once every week or two. I do a ten minute warm up and spend about 15 minutes doing scales, trills, and hums. I spend another 10-15 minutes practicing songs.
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