How much low frequency absorbers do I need?Help

Hi every one I do not write english wery well but i will try. My question is how much low frequency from 20-200 hz absorbers do I need for my room to get good result? Dimension 7,4m long 3,85 m width and 2,94 hight.All walls are made in brick the floor is oak parquet the celling is allso brick. I understand there are absorbers like hangers,panel absorbers,helmholtz resonator,porose and ....But I have try with helm holtz about 3000 litars on 30hz,45 hz and 63 hz but no result.I mesaure with Berenger mic and EQ wizard software.

I have a better idea: Please read the forum RULES (stickies) that can be found at this link: viewforum.php?f=17 Then make certain that this is reviewed: viewtopic.php?f=2&t=3231 Please correct your initial post to conform with these rules and guidelines. Many here will not only NOT help while waiting in respect for owners and other better qualified persons to proceed, but will simply ignore these type of posts completely. You may want to immediately ask "what is it that I have missed". Most often it is as simple as including your geographical location in your profile. It might be that you have not included your budget! Trust me in that the more you know the better others can help you and that the answer to that question is in the forum rules linked page. Until then, good luck, Brien