Room Treatment, Panel Sound Diffusers


So I am setting up a third sound system in a spare bedroom.  I want to really get the walls and perhaps ceiling treated for optimal sound.  The bed will be taken out.  I will put in high quality duplexes like the ones sold by Cullen Cables.  However, there are a bunch of different sound diffuser panels with many being quite expensive.  I am going to do the install myself so nothing too complicated.  Looking for advice on the type of wall treatment that works but won't break the bank.

Thanks!
jaymark
For $100 per 4 x 2 ft panel I’d easily go with GIK as it will include a wooden frame and diffusor which is really advantageous compared to straight Owens Corning absorption. You could never make this for $20 per panel, they will be perfect in presentation and identical, and look nice with options to tailor to your aesthetic.

https://www.gikacoustics.com/product/2a-alpha-panel-diffusor-absorber/






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Ditto the GIK recommendation.  I just redid my room with their product.  Good advice, good products and very affordable.  Their 244 panels are excellent as are various diffusors.
What is your sources?

I have acoustic panels from,

https://www.gikacoustics.com/

in a small bedroom with a floor stander. Look at my virtual system. If not for the fact that 2 of my sources are analog, SACD, tuner, I would not get the panels from these guys. The panels do the job but in an all-digital setup that is not how I would do it.

I am playing some ZZ Top via a digital stream right now at 75 db. Sounds fabulous in this small room.