Magnepan 20.1 versus Infinity IRS Beta

If you are considering each option why wouldn't you also consider the new 20.7?
This is not an answer to your question and I don't think the new 20.7 will extend the bass further.
But it seems to me you (especially since you are at close to the same price point) that you might want to consider the 20.7 instead of the 20.1

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Because you don't mention the 20.7, price must be a concern. You can buy a set of Betas, if you can find them for around $5-6k and Maggies around $7-9k. I would suggest getting the Maggies and a pair of good subs. The Betas are great speakers, but they are also 24 years old. Parts and repair will be a hassle with the Betas. Going the Maggie/sub route will be more expensive, but I believe that route will be more practical...plus you will get excellent sound. You need a big room for the 20.1, you'll need a huge room for the Betas.
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