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Continue on Chris... The majority of us understand and appreciate what your doing! We know it's not perfect, but it provides very useful information
If the test is flawed the data is only relevant to this specific test under the conditions present. I'm very concerned about the validity of the results. A lot of people are watching.
 

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Discussion Starter #302
Everyone knew going in that testing was very conditional (as are all tests of any kind). You can't point me to any test that is absolute for all conditions.

Right now, the general public here has nothing but what companies and certain people have told us. There have been no results published, no test methods explained, and no attempt to prove what they are claiming is actual truth.

So far Don is the only person to suggest that the information gained is not useful in any way. For Don to come in and claim that the information is not useful, when he has admittedly not read the entire thread, is irresponsible. I've had many people look over everything. I've had someone with a masters in physics sit in on testing with me. His response to this is that people will always be critical, especially when they are watching from the outside in. He feels the information is more useful than anything else out there on these products.

Of course there are room for improvements. I can think of many things, that the next time I do this, will be better. Those things have to wait for me to have a better budget for this, the people that have donated products are aware that this is an initial testing. I will finish up this testing as is, put a lot of work into extrapolating the usefulness of the results, and wrap it all up in neat presentation.
 

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Discussion Starter #303 (Edited)
Just so everyone is clear, here is the test procedure. I have full video, documenting the entire process, but as it takes 3 hours to upload 12 minutes of video for me, I will be saving it for the final results.

1 - Place metal plate between clamping frame and box. Insert bolts, and finger tighten until snug, north to south, west to east, north west to south east, north east to south west. Repeat pattern torquing bolts to 60 in-lbs. Measure temperature at multiple locations with infrared thermometer, temps must be between 77-77.5 degrees.

2 - Position mic, lining up the tip with the center of the x lightly scribed into the test panel. Check distance from panel with 0.016" feeler gauge from the face of the bolts.

3 - Run 8 measurement sweeps with REW. If the headroom isn't between 4.8-5.3db, check everything and re-run them. Save file, and save snapshots of frequency response and waterfall.

4 - Remove backing paper from sample to be tested. Samples are all cut out with the same die, and center is removed with a die to prevent the thickness/density from affecting readings. Weigh sample, metal side down with backing removed, with a sharper image food scale, in grams. Apply sample, and use rounded edge on putty knife to make sure entire piece is adhered. This is admittedly one of the weak points. Each sample takes about a minute, taking extreme care to use as close to the same amount of force per sample as possible. I actually practiced this on a scale, a few times a day, for a week. After sample is in place, measure temperature at multiple locations. All locations must be between 77-77.5 degrees.

5 - Reposition mic as before. This takes a few minutes, since each sample will have a different headroom, I have to check multiple times. I usually walk away and check again before repeating the measurement process with another 8 sweeps. Save file, save snapshots of overlayed frequency response, damped frequency response, and damped waterfall.

6 - Remove panel. Place on flat surface and pry sample up with putty knife. Remove entire sample, then clean with googone (for butyl) then acetone, or just acetone for asphalt. Clean panel again inside with alcohol. No abrasives are used on the panel.

7 - Start at step 1 again.



Every sample gets its own bare metal measurement. The metal is never unbolted between metal and damped measurements.


I will begin testing the remaining samples on weds. I took my mom in for an MRI today, and my sister in law will be over tomorrow.

I'm not going to argue over the testing procedure. I am aware of the issues, and very specifically asked in this thread if people wanted me to continue. The resounding answer was yes. If you have criticism, by all means speak up. But bring a solution to the table. Criticism without a solution is a waste of your time and mine.
 

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F'ing amazing how they come out of the woodwork. :mean:
Maybe it's because they have a dog in the hunt.
Hang in there Chris.
No one else is willing to do all this work for the DIYMA community.
A big thumbs up!


Bret
PPI-ART COLLECTOR
 

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I think at this point changing the test procedure would be counter-productive since the data we are seeing makes sense versus what most people were expecting. The process has been vetted by you and professionals on here and in person where the testing is taking place. We all appreciate what you are doing and are looking forward to the end of the test and results.

If someone has an issue with the testing, bringing it up in this thread is simply post dumping. Pm's would be more appropriate and would keep the thread de-cluttered. I hate seeing things like this go so far and then mud slinging starts and things go down hill. This is a DIY site, let's keep it DIY, keep the info flowing and share knowledge...otherwise we are undermining the entire purpose of this site.


Just so everyone is clear, here is the test procedure. I have full video, documenting the entire process, but as it takes 3 hours to upload 12 minutes of video for me, I will be saving it for the final results.

1 - Place metal plate between clamping frame and box. Insert bolts, and finger tighten until snug, north to south, west to east, north west to south east, north east to south west. Repeat pattern torquing bolts to 60 in-lbs. Measure temperature at multiple locations with infrared thermometer, temps must be between 77-77.5 degrees.

2 - Position mic, lining up the tip with the center of the x lightly scribed into the test panel. Check distance from panel with 0.016" feeler gauge from the face of the bolts.

3 - Run 8 measurement sweeps with REW. If the headroom isn't between 4.8-5.3db, check everything and re-run them. Save file, and save snapshots of frequency response and waterfall.

4 - Remove backing paper from sample to be tested. Samples are all cut out with the same die, and center is removed with a die to prevent the thickness/density from affecting readings. Weigh sample, metal side down with backing removed, with a sharper image food scale, in grams. Apply sample, and use rounded edge on putty knife to make sure entire piece is adhered. This is admittedly one of the weak points. Each sample takes about a minute, taking extreme care to use as close to the same amount of force per sample as possible. I actually practiced this on a scale, a few times a day, for a week. After sample is in place, measure temperature at multiple locations. All locations must be between 77-77.5 degrees.

5 - Reposition mic as before. This takes a few minutes, since each sample will have a different headroom, I have to check multiple times. I usually walk away and check again before repeating the measurement process with another 8 sweeps. Save file, save snapshots of overlayed frequency response, damped frequency response, and damped waterfall.

6 - Remove panel. Place on flat surface and pry sample up with putty knife. Remove entire sample, then clean with googone (for butyl) then acetone, or just acetone for asphalt. Clean panel again inside with alcohol. No abrasives are used on the panel.

7 - Start at step 1 again.



Every sample gets its own bare metal measurement. The metal is never unbolted between metal and damped measurements.


I will begin testing the remaining samples on weds. I took my mom in for an MRI today, and my sister in law will be over tomorrow.

I'm not going to argue over the testing procedure. I am aware of the issues, and very specifically asked in this thread if people wanted me to continue. The resounding answer was yes. If you have criticism, by all means speak up. But bring a solution to the table. Criticism without a solution is a waste of your time and mine.
 

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I for one appreciate the input of an industry long timer. I don't appreciate the manner of approach, but if we could get to solutions that would be great.

I feel that the accelerometer would be the more proper test for a panel and the mic would be better for the car door. I am likely wrong as I'm not an engineer or physics major, but if you need help buying an accelerometer I will make a donation thread to get this back on track.
 

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Discussion Starter #307
^I'll pm you in the morning. Its WAY past my bedtime.


I wont be changing anything about the current testing method or procedure. After everything with this series of tests is wrapped up, and I post detailed results of everything I've done, I will begin to look at what can be improved upon in future tests. At the time I do those future tests, we can then compare the (more than likely improved) test's results vs the current tests results, and see if they are close, or way off.

I was trying to keep Don and I's conversations private, we've actually been discussing things for a few days, and he had offered to send additional product. It seems as though he hadn't paid attention to the thread at all though. Just for the record, I don't think Don is on an attack because his product is on the line (although its doing quite good), and I don't hold anything against him. I just think he handled this the wrong way. To me, it just seems that he is an idealist about this, and I can understand that. It took a lot for me to accept the compromises that had to be made to get this going. But as Bing once told me, be careful of being a perfectionist. You end up with a lot of things unfinished, because it will never be good enough. Oddly enough, the engineer that sat in on testing with me has told me the same thing for years, since I was a kid.
 

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As I've said, you are doing a great job. Is it perfect, probably not, nothing is. But this is by far the most comprehensive and accurate test to date that I know of, and find the results very informative.

Swyped while swerving
 

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One thing I have noticed is that most people want to funnel all CLD testing into one category...resonance control. I use CLD for that as well as making the sheet metal thicker in the area that it is applied. IMO, the results of this testing apply to that as well. I've had people argue with me that CLD will not block noise. I usually take a piece and tell them to hold it against their ear and they change their opinion, but scientific it is not.

My point in saying this is, maybe Don is looking at it from his testing/marketing angle and sees these tests as worthless from that direction. Can't be sure until he clarifies, but that might be the case.

I wont be changing anything about the current testing method or procedure. After everything with this series of tests is wrapped up, and I post detailed results of everything I've done, I will begin to look at what can be improved upon in future tests. At the time I do those future tests, we can then compare the (more than likely improved) test's results vs the current tests results, and see if they are close, or way off.

I was trying to keep Don and I's conversations private, we've actually been discussing things for a few days, and he had offered to send additional product. It seems as though he hadn't paid attention to the thread at all though. Just for the record, I don't think Don is on an attack because his product is on the line (although its doing quite good), and I don't hold anything against him. I just think he handled this the wrong way. To me, it just seems that he is an idealist about this, and I can understand that. It took a lot for me to accept the compromises that had to be made to get this going. But as Bing once told me, be careful of being a perfectionist. You end up with a lot of things unfinished, because it will never be good enough. Oddly enough, the engineer that sat in on testing with me has told me the same thing for years, since I was a kid.
 

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I tried, but I can't not comment on this:

...
It's irresponsible to ask people to alter their behavior based on something as imprecise as what you are doing. I think this is a case of pretty pictures concealing a very poor methodology.

Sorry to see this.
Rather strange to be talking about irresponsibility while at the same time criticizing a project, sowing seeds of doubts regarding its reliability, without explaining why you think so.
There are many words I could use to describe such behavior...none considered very flattering...


"If the test is flawed the data is only relevant to this specific test under the conditions present. I'm very concerned about the validity of the results. A lot of people are watching."

So he says jump you ask how high?
Are you not at all interested in hearing "why" before you make up your mind about this?

Impressive mind-controlling skills there Darth Don...


(how does one do two qoutes in here btw?)
 

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Chris is providing data from a consistently methodology.

Its up to the individual to interpret/use these results as he/she see's fit.

It is a tremendous service he is providing.
 

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Chris, I know you do not intend on changing your methodology now that you have begun testing (and rightfully so, as it would make results difficult to compare), however I wonder if you had a chance to speak with your dad about the idea of using a hall-effect transistor instead of a microphone. I still feel it would be more appropriate, as it more directly measures the panel movement using magnetics, rather than sound pressure waves (also avoiding ambient noise, etc).

Also, in the pictures you posted of your test setup, I noticed that the microphone was firmly mounted to the same board the speaker box was mounted too. I believe you mentioned that you even epoxied the microhone mount to it. I have read this entire thread, and I remember earlier someone suggested that you attempt to decouple the microphone from this speaker. Have you put any consideration into this?

cheers, and keep up the good work!
 

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Discussion Starter #314
Short and quick answer while im on my phone, ill expand later.

I havent had the chance to talk with him yet, he was here last week, but I was very busy getting ready for my interview. He'll be back in town next week, and ill discuss it with him. I've actually been working on design for the next test procedure, and although thats a good while a way, ill be discussing that with him as well.

As for the mic, the pictures are hiding a gap between the mic board, and test box. There is about a half inch gap between the mic board, and the test box. I did test with some closed cell foam underneath, but the results actually varied more with it in place than without it, so I left it out.
 

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Did I miss the other STP products? How did they do compared to the Bomb? I saw one photo where they showed where they apply the different products. Wondering if there is one that "does it all" aside from a CCF or MLV or similar top layer like Ensolite etc.

Curious if anyone has any experience with this "value" product I found on ebay. 1 New Bulk Roll Mat 100 sqft Butyl Rubber Use as Auto Sound Deadener Material | eBay
Thinner aluminum backing (2mil) but has a fiber built into or onto it for strength and it is cheap enough that I could double it up alot for the same price as the name brand stuff. It is a butyl product which is what caught my eye. Need to do my car but don't have the budget for the top shelf stuff so I am very interested in how some of the "cheaper" products are doing. Def. impressed with the STP Bomb.
 

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I think a camera with a very narrow aperture can blur out the background like that on a closeup like that.. but I see what you are saying. They do have a clear pic of it next to another type of product.. no explanation what they are showing though. Has a grayish looking core. This stuff is originally an HVAC product. I know more or less you get what you pay for just kind of wondering since it is a butyl product if it would perform any better and be less smelly and gooey than your basic peel and seal asphalt stuff. I won't keep debating about it here so I jack the thread, just curious if anyone had used it and any thoughts.
 

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Discussion Starter #318
I haven't done the other STP products yet, that will be done tomorrow. I have Silver and Gold to test tomorrow, and some time after that, Vizomat, which is the oem equivalent.

Not sure on the product your asking about. There is a definite difference in butyls throughout the products. Before testing, I would have said get the product with the thickest constraining layer, but now, not so much.
 

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If I can get a sample of that ebay product I mentioned, would you mind testing it and seeing how it compares to the others? How much do you need to do an accurate assessment?
 

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If I can get a sample of that ebay product I mentioned, would you mind testing it and seeing how it compares to the others? How much do you need to do an accurate assessment?
I have some of this actually DJ... I can send it over to you Chris if you have time to test it?
 
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