The problem with cost analysis comparisons from the various vendors is that the absolute cost is not very meaningful, within reason. What one needs to focus on is the cost effectiveness of the various products. That is not a simple matter of Sabins/dollar. The traps don't sound the same. I have a variety of products in my room. I've got RealTraps Mondo traps, GIK soffit traps, Mega traps, 6 alphas, Tritraps, and a variety of the GIK 242 and 244 type traps. Most of these traps are range limited in order to address LF ringing. I get the best sound with my RealTraps (limp membrane type) mounted on the front walls, soffit traps in the front corners, Real Traps Mondo in the right rear corner, a GiK Tritrap in the left rear corner, and GIK 6 alphas on the rear wall. The LF traps are not interchangeable in terms of sound.
I am a die hard advocate of using REW to make room treatment decisions, but I can't tease a rationale out of the measurement data to explain why a given low frequency trap sounds better than another in a given location. I made the decision to defer permanent installation of traps until I was finished. So I can still switch out locations on most of my traps even now.
Most of us are not inclined to run A/B comparisons of different trap types in our own rooms. The only reason why I did this is because I added my traps in 3 different phases and ended up with a bunch of different stuff.
Let me be clear- There is a reason why I haven't bought any of Foley's products, and it is not because of their cost in absolute terms. I don't know how much carbon are in his traps, but the activated carbon he uses runs from about $80-$200 per kilogram. His traps aren't going to be nearly as easy to build as a GIK Monster trap. I might suggest the price of his traps is reasonable based on what I think it would take to make them. The key question is "Are they competitive on a cost/perfomance basis. He doesn't make that argument, but rather makes an argument that you will die instantly from beta particles shooting out of the fiberglass. Sorry, I ain't buying that snake oil.
I think the best approach for someone starting fresh in an untreated room is to take a somewhat theoretical approach. Limp membrane traps have an inherent advantage for use in high pressure zones such as front walls and corners. RealTraps, in my estimation, is the best source of limp membrane traps. Backwalls, depending upon distance from the listening position, can benefit from a mixture of traditional absorption and diffusion. I think this is why I had such good luck with GIK 6 alphas in that position. I think that what works best for sidewall first reflection points is heavily dependent on the width of the room. I would be reluctant to generalize on that. I prefer to leave side walls forward of the first reflection points untreated, and use traditional fiberglass absorption behind the first reflection points.
I didn't have a clue what I was doing when I started. Somehow, by a mixture of hard work, aptitude for physical sciences, and dumb blind luck I took a room that was miserable and transformed it to one that was quite good. I've got about 7K in the project including a Swarm sub system but not counting replacing my flooring at a cost of 3.5 K, which in my room, was absolutely necessary. Spending 10K in anything like a normal room should be more than enough. The hard part is learning enough so you can be smart about what you do.
