Need advice on stirrer plate

Just starting to make yeast starters. Noticed the cell count is much higher if a stir plate is used. Stir plates run from $70 to over $200. What do you use? Want one that runs quietly.

Currently use a 3 L wine jug with a cap drilled and grommeted for an airlock. What would be the benefit of getting a 3 L flask, assuming the stir bar will remain centered in the concave bottom of the wine jug? Any thoughts on what size stir bar to get?

Make your own.

Go to te diy section of homebrewtalk.com. There is always 2 or 3 threads there about how to make one. All it takes is a cheap pc fan, a magnet, a small box, and some wired and a potentiometer. $20.

Stirstarters.com. Can't beat the price and lifetime warranty. Get the 2 ltr flask, u won't be sorry

Toy4Rick

So a 2 L flask will work for a 2 L starter? Thought it would take a 3 L to allow for cell growth. Should an airlock be used. A reply form another site said yeast needs a free exchange of oxygen and an airlock defeats the purpose. On the other hand see flasks sold with stoppers and airlocks. Yeast starter directions often say use an airlock but sanitized aluminium foil with holes will work.

You can only fill a flask about 80%.  So you need a 3l flask to make 2l starter.

No airlock on the starter. Loosly Cover the flask with sanitized foil.  You are correct that you want o2 to get into the flask, and an airlock would prevent that. The foil keeps infection out, while letting o2 in. It should just be loose, not tight.

If you get a Stir Starter, look for a larger stir bar than the one that ships with it.  One of my brew buddies recommended to me that I get a larger one with a ring around the middle for the larger starters.