Room Gain and subwoofers

[shadyJ]

Hope this doesn't get me yelled at too much here but Dr. Earl Geddes doesn't even really believe in room gain with regards to low frequency pressure producing devices. He states rooms in homes are too leaky for that to have any real effect.

I don't know what Dr. Geddes originally said, but I think maybe you are misunderstanding what he meant. The science of pressure vessel gain is pretty well understood, and the body of evidence of this effect is well beyond dispute. I don't think that Geddes would argue against that. If he were to say that pressure vessel gain is misunderstood and too often assumed in circumstances that do not support it, I would agree.

 

[roadwarrior]

Believe in? Doesn't sound quite right, at least not without some measurements to bear that out....and then that would be dependent on room construction.

I worded that badly. He doesn't believe you gain any with a subwoofer placed in a small room. He designs and builds his own speakers and subwoofers so I'm sure he recognises its existence just not the level of weight it's given with regards to its effect with subwoofers. Poor wording on my part the first time about his thoughts on this. Sorry Dr. Geddes.

 

[roadwarrior]

I don't know what Dr. Geddes originally said, but I think maybe you are misunderstanding what he meant. The science of pressure vessel gain is pretty well understood, and the body of evidence of this effect is well beyond dispute. I don't think that Geddes would argue against that. If he were to say that pressure vessel gain is misunderstood and too often assumed in circumstances that do not support it, I would agree.

No, that was just my poor wording of his thoughts on it not my misunderstanding of them( my bad.) He just doesn't believe there's any appreciable level of it with regards to subwoofers placed in room to consider it noteworthy.

 

[lovinthehd]

I worded that badly. He doesn't believe you gain any with a subwoofer placed in a small room. He designs and builds his own speakers and subwoofers so I'm sure he recognises its existence just not the level of weight it's given with regards to its effect with subwoofers. Poor wording on my part the first time about his thoughts on this. Sorry Dr. Geddes.

I've read some of his multi-sub stuff, but been a while. I'm thinking he probably has more specifics involved....

 

[roadwarrior]

I've read some of his multi-sub stuff, but been a while. I'm thinking he probably has more specifics involved....

As have I but the long and short of it is he believes you only really get appreciable room or cabin gain in an automobile ( he worked for the Ford Motor Company for a number of years as well) and extrapolated into a home environment it's effectiveness is severely limited as rooms in homes are too leaky to gain any benefits. No pun intended.

 

[lovinthehd]

As have I but the long and short of it is he believes you only really get appreciable room or cabin gain in an automobile ( he worked for the Ford Motor Company for a number of years as well) and extrapolated into a home environment it's effectiveness is severely limited as rooms in homes are too leaky to gain any benefits. No pun intended.

Gotcha. Still depends on the room and construction but of course it won't be on the level of such a small room as a car.

 

[djreef]

As have I but the long and short of it is he believes you only really get appreciable room or cabin gain in an automobile ( he worked for the Ford Motor Company for a number of years as well) and extrapolated into a home environment it's effectiveness is severely limited as rooms in homes are too leaky to gain any benefits. No pun intended.

He's also never visited my dedicated music room.

While I agree that at the time he wrote it, things may have been different wiith residential construction standards. Houses built now are pretty tight compared to houses built even 20 years ago. Newer govt restrictions put in place to prevent a similar type of leakage, but from an energy conservation standpoint, has seen to that.

DJ

 

[roadwarrior]

Gotcha. Still depends on the room and construction but of course it won't be on the level of such a small room as a car.

Yep, it's above my pay grade ( even though I was in the auto industry for a long time myself and was aware of cabin gain then) but if true makes me feel a lot better about getting the 2 ported subwoofers I currently have instead of the sealed I had buyer's remorse over after getting my sub's initially. I stressed over that for almost a week afterwards as I'm in a very small sealed room. Would be nice to have space for more than 2 ported by going sealed though. Hmmm....Somebody please stop me before I buy another subwoofer.

 

[roadwarrior]

He's also never visited my dedicated music room.

Lol, I bet. Also probably wasn't talking about his dedicated audio room as well ( he floats the double laminated walls on springs.)

While I agree that at the time he wrote it, things may have been different wiith residential construction standards. Houses built now are pretty tight compared to houses built even 20 years ago. Newer govt restrictions put in place to prevent a similar type of leakage, but from an energy conservation standpoint, has seen to. DJ

I hear you and I understand that but I wasn't talking about some paper or lecture he did 20 years ago. This was pretty recent and his house looked pretty new to me from the inside. As fast as some of my home builder clients were putting up houses in my part of the country a few years ago I'd be surprised if there was much difference affecting room gain at low frequencies over the years but again I'm pretty sure he was referring to current not older home builds. On a side note I'd love to hear what music sounds like in your music room. Color me jealous.