Back when this podcast began (several years ago) I used BlogTalkRadio, because I didn't know much about podcasting and sound quality. I never attracted more than 30-something followers on BlogTalkRadio.
When I switched my podcast to the Spreaker platform in 2014-2015, I immediately noticed an improvement in sound quality. I also noticed that I was attracting thousands of followers -- and tens of thousands of downloads/listens. While I can easily attribute this to the fact that I was discussing some very high-profile topics on my show, I really would like to think it had a lot to do with quality.
That is why the Case to Case podcast has switched back to the Spreaker platform. As of the next episode -- Wed., Jan. 11, 2017 -- you will listen to my podcast in far better quality. The sound will be richer, clearer and less tinny. The problem with BlogTalkRadio is that no matter how expensive your studio equipment is, it sounds like you're broadcasting through a telephone. This could be due to their system originally being set up for telephone use, but I use the direct-connect feature -- using my Blue Yeti microphone. The quality is still terrible. Yes, I am still complaining about this.
Overall, I think it's best for the Case to Case podcast to stay on Spreaker. Judging from the number of downloads and followers I have on that platform, I think it's safe to say that you guys agree.