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fuzz092888

fuzz092888

Audioholic Warlord
It is mathematically impossible to have any alignment with a lower Qt, than the Qts of the driver, so draw your own conclusions about that program.
That doesn't answer my question at all and makes the assumption that the program was giving me a Qtc that was lower than the Qts of the driver. None of the models that were run through the spreadsheet returned a Qtc lower than the Qts of the driver, however the larger boxes, according to the excel spreadsheet yielded a lower Qtc than the small box. So I was asking, why this might be. I can email you the spreadsheet if that would help makes things clearer for you or post images of the results from each model.
 
TLS Guy

TLS Guy

Seriously, I have no life.
That doesn't answer my question at all and makes the assumption that the program was giving me a Qtc that was lower than the Qts of the driver. None of the models that were run through the spreadsheet returned a Qtc lower than the Qts of the driver, however the larger boxes, according to the excel spreadsheet yielded a lower Qtc than the small box. So I was asking, why this might be. I can email you the spreadsheet if that would help makes things clearer for you or post images of the results from each model.
According to your original post the Qts of the driver is 0.814. My alignment gives a Qt of 0.814 which is optimal, and will provide optimal restoring force.
Any other data you may have is wrong. I leave for England tomorrow and this is my last word on the alignment.
 
fuzz092888

fuzz092888

Audioholic Warlord
According to your original post the Qts of the driver is 0.814. My alignment gives a Qt of 0.814 which is optimal, and will provide optimal restoring force.
Any other data you may have is wrong. I leave for England tomorrow and this is my last word on the alignment.
My apologizes, I missed that back there where you said your model gave a Qt of .814.

I'm curious as to where this spreadsheet goes wrong since it was able to do everything else correctly, and by that I mean there are parameters that I am not able to fill in, but that I have data for and it gives me the proper values. I wonder why then the box alignment wouldn't be much closer to what you modeled.

I'll have to see if I can upload the excel sheet and see if someone else can make sense of it.

Hmm can't upload it. If there's anyone out there who has modeling software that they can compare this against I'd appreciate. I can't upload the file, but I can probably e-mail it. Thanks in advance.
 
TLS Guy

TLS Guy

Seriously, I have no life.
My apologizes, I missed that back there where you said your model gave a Qt of .814.

I'm curious as to where this spreadsheet goes wrong since it was able to do everything else correctly, and by that I mean there are parameters that I am not able to fill in, but that I have data for and it gives me the proper values. I wonder why then the box alignment wouldn't be much closer to what you modeled.

I'll have to see if I can upload the excel sheet and see if someone else can make sense of it.

Hmm can't upload it. If there's anyone out there who has modeling software that they can compare this against I'd appreciate. I can't upload the file, but I can probably e-mail it. Thanks in advance.
I rounded the numbers off in my head before modelling it, and knew that driver needed a sealed box of around 5 cu.ft and the model of Bullock and White confirmed it.

I have never heard of an sealed enclosure of the size you were quoting for any driver. At 5 cu.ft you are on the high end of any sealed alignments I'm familiar with.
 
fuzz092888

fuzz092888

Audioholic Warlord
I rounded the numbers off in my head before modelling it, and knew that driver needed a sealed box of around 5 cu.ft and the model of Bullock and White confirmed it.

I have never heard of an sealed enclosure of the size you were quoting for any driver. At 5 cu.ft you are on the high end of any sealed alignments I'm familiar with.
The only other time I've heard of a sealed box that large was when I questioned Josh Ricci about making the RE XXX 18" in a sealed box and if it was possible. He told me that a box of 9 cu. ft should be about right. You and he both have forgotten more than I know about this stuff so I'm just trying to reconcile the two pieces of conflicting information with the spreadsheet in front of me.

I'm also not putting blind faith in this random spreadsheet, but it seems to be doing more things right than it is doing wrong, so I'm just curious as to where it is going wrong.

Oh, also, the guy I bought the sub from has been doing this quite awhile so I assumed he knew what he was doing as well. He also provided drivers that were in the Simply Sound Audio Rhumba which got a pretty good review from theJman which led me to believe he had an idea.

I'm just trying to make sense of it all :eek:
 
TLS Guy

TLS Guy

Seriously, I have no life.
The only other time I've heard of a sealed box that large was when I questioned Josh Ricci about making the RE XXX 18" in a sealed box and if it was possible. He told me that a box of 9 cu. ft should be about right. You and he both have forgotten more than I know about this stuff so I'm just trying to reconcile the two pieces of conflicting information with the spreadsheet in front of me.

I'm also not putting blind faith in this random spreadsheet, but it seems to be doing more things right than it is doing wrong, so I'm just curious as to where it is going wrong.

Oh, also, the guy I bought the sub from has been doing this quite awhile so I assumed he knew what he was doing as well. He also provided drivers that were in the Simply Sound Audio Rhumba which got a pretty good review from theJman which led me to believe he had an idea.

I'm just trying to make sense of it all :eek:
I don't think those sources understand the limitations of models. If you enter nonsense you get nonsense. I tried my program with your box sizes and it produced data that was not possible. All programs have a garbage in, garbage out factor. This is where knowledge and experience aces everything else.
 
fuzz092888

fuzz092888

Audioholic Warlord
I don't think those sources understand the limitations of models. If you enter nonsense you get nonsense. I tried my program with your box sizes and it produced data that was not possible. All programs have a garbage in, garbage out factor. This is where knowledge and experience aces everything else.
That makes perfect sense. Again, I really appreciate your time and patience with me. :D

Cheers and have a great trip!
 
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