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post #1 of 32 Old 05-03-2012, 05:07 PM - Thread Starter
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In an attempt to have my subwoofer reviews be more objective I decided to make time -- you know how that goes -- to learn how my XTZ Room Analyzer II Pro functions. I've read the manual twice now, so I have at least a passing familiarity with all the features (which turned out to be more then I had anticipated).

My first set of measurements have been taken, so I wanted to get some feedback from those who know about measured testing to see if these numbers appear legit. I already have an opinion formulated, now I need to see if the neophytes measurements -- that would be me -- are corroborated by people who know what they're doing.

I tested two different subwoofers, the Simply Sound Audio Rumba 12 I just recently reviewed, and another sub I'm currently reviewing. The former is acoustic suspension with a front-firing 12" driver, while the latter is an 8" driver with an 8" passive radiator. That one has the driver and PR on opposite sides of the cabinet. For both subs I pointed the mic directly at the center of the driver, exactly 1 meter away. They were at least 1.5 feet from the nearest wall. The room is carpeted.

I disabled the PEQ on the Rumba, so no boost or cut was used. The PR was not mic'ed for this test. The XTZ software has a meter which denotes clipping so all tests were run up to clipping, then the gain was turned down to just below that point. You only have preconfigured tones you can send out, so the possibilities aren't endless, which is why you'll see gaps between the frequencies. I started at the lowest -- 10Hz -- and stopped at 125Hz, even though I could have gone to 250Hz. 125Hz seemed like a reasonable ceiling to me though, so I'll probably stick to that in the future as well. I haven't figured out how (if?) to save the graphs in JPG or PNG format yet, so unfortunately there are no pictures to show.

That should cover all the background info, so without further ado...

Simply Sound Audio Rumba 12
10Hz - 86dB
12.5Hz - 91dB
16Hz - 97dB
20Hz - 98dB
25Hz - 106dB
31.5Hz - 109dB
40Hz - 110dB
50Hz - 107dB
63Hz - 114dB
80Hz - 116dB
100Hz - 109dB
125Hz - 105dB


The sub I won't identify just yet
10Hz - 57dB
12.5Hz - 60dB
16Hz - 67dB
20Hz - 77dB
25Hz - 89dB
31.5Hz - 98dB
40Hz - 101dB
50Hz - 94dB
63Hz - 103dB
80Hz - 107dB
100Hz - 107dB
125Hz - 103dB


The Rumba 12's numbers look like what it sounded like to my ears, so I'm pretty content with that one. The unidentified sub looks about right too, except for that bizarre dip around 50Hz (which I tested 3 times, just to make sure I wasn't losing it), so I image it's probably pretty accurate as well.

But that's a novice talking, now I'd appreciate hearing from those who know what they're doing. Do these numbers look as though they could be legit to you? I realize without having actually heard the subs yourself you can't make a definite assessment, but in general how do they fair? I want to see if I'm doing this properly, or if I need to go back to the drawing board.

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post #2 of 32 Old 05-03-2012, 05:14 PM
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I don't have a clue as to the operation of that "thing". But both subs show a drop a 50hz. The 8" sub obviously having a greater drop.

That said I can only assume you have a 50hz null at the spot of the mic.

And- great now even better reviews! Keep up the good work.

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post #3 of 32 Old 05-03-2012, 05:35 PM - Thread Starter
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Quote:
Originally Posted by Kini62 View Post

I don't have a clue as to the operation of that "thing". But both subs show a drop a 50hz. The 8" sub obviously having a greater drop.

That said I can only assume you have a 50hz null at the spot of the mic.

Good point - I didn't even realize that. I got so hung up on the fact the unidentified sub had such a huge drop at 50Hz that I failed to notice a commensurate pattern for the Rumba. See, that's why the amateur is asking for extra eyes!


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And- great now even better reviews! Keep up the good work.

Thanks man. I knew that aspect was lacking, but I just never seemed to find the time to drag this thing out and learn how to use it. I'm not sure when the numbers will show up in my reviews, because I really don't feel confident yet that I know what I'm doing, but they will come eventually. At that point maybe I'll be like Josh Ricci and ask for $200 a pop...

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post #4 of 32 Old 05-03-2012, 07:00 PM
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Can you just post the graphs? They're a lot easier to glean information from than a table:

My RTA:


Craig

PS. Congrats on getting to the point of taking measurements. The measurements are far more useful than subjective impressions.

PPS. The FR graphs and the 2D waterfalls are a lot more useful and meaningful than the 1/3 octave full range RTA's.

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Perfection is not attainable, but if we chase perfection we can catch excellence."


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post #5 of 32 Old 05-03-2012, 07:42 PM - Thread Starter
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Quote:
Originally Posted by craig john View Post

Can you just post the graphs? They're a lot easier to glean information from than a table:

How did you do that??? I can't find a way to save in any other format then PIR, whatever the heck that is. How did you get a JPG?


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Originally Posted by craig john View Post

PS. Congrats on getting to the point of taking measurements. The measurements are far more useful than subjective impressions.

Since the numbers pretty much mirrored what my ears heard -- and subsequently what my review expressed -- I'm not certain I'd classify them as "far more useful". But your point is valid nonetheless, and it is something I've wanted to do for a while. Now I just have to get a little more familiar with all the potential tests and their respective options.

Do you have the Pro version as well?

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post #6 of 32 Old 05-04-2012, 10:11 PM - Thread Starter
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Alright, let's try this again... I attached a few pictures of how I mic'ed the Rumba 12, along with a graph created using the pink noise generator.
LL
LL
LL
LL

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post #7 of 32 Old 05-05-2012, 05:56 AM
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If you're measuring subs, use the FR graphs and 2D waterfalls:





These are much more useful than the 1/3 octave RTA's.

Craig

Lombardi said it:
Perfection is not attainable, but if we chase perfection we can catch excellence."


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post #8 of 32 Old 05-05-2012, 10:24 AM
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Quote:
Originally Posted by craig john View Post

Can you just post the graphs? They're a lot easier to glean information from than a table:

My RTA:


Craig

PS. Congrats on getting to the point of taking measurements. The measurements are far more useful than subjective impressions.

PPS. The FR graphs and the 2D waterfalls are a lot more useful and meaningful than the 1/3 octave full range RTA's.

Yeah, in the Audioholics review of the $9,000 Paradigm Sub 2 Josh Ricci used twice as much space on measurements as he did on listening experience. Meanwhile, some people think the best reviews are 90% subjective and 10% objective...
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post #9 of 32 Old 05-05-2012, 10:51 AM - Thread Starter
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Originally Posted by spyboy View Post

Meanwhile, some people think the best reviews are 90% subjective and 10% objective...

Yup, and I still do believe that.

You just never quit, do you? Don't you have any other goals in life but to be petty and immature?

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post #10 of 32 Old 05-05-2012, 02:09 PM
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Originally Posted by JimWilson View Post

Yup, and I still do believe that.

You just never quit, do you? Don't you have any other goals in life but to be petty and immature?

Your opinion that the best reviews are 90% subjective and 10% objective is way out of line with the better subwoofer testers including professionals like:

Don Keele who designed speakers for JBL. And, he really designed them, not just offering up very minor incremental revisions like adding an addional 8 ounces of poly fill

Don was the primary speaker and subwoofer tester for Audio Magazine and his reviews are exemplary. Don has been working on CEA 2010 recently.

Tom Nousaine. That is who Chad Kypers of Epik choose to review the Epik flagship Conquest. Tom's review is virtually all numbers. This is what Chad said about Tom's review:

"Tom Nousaine recently measured and tested our flaghip subwoofer, the Conquest. He has been reviewing subwoofers for many years and has earned a reputation as an incredibly knowledgeable reviewer. We were excited to see how our flagship subwoofer stacked up against other subwoofers in the industry. Most notably we wanted to see how it stacked up alongside of the best subwoofers he has ever measured."

The review of the $1,600 Conquest compares it to the $15,000 Velodyne DD-1812 and the $10,000 Genelec HTS-6. After presenting his measurements, Tom summarizes his review by saying:

"This system has Herculean SPL capability compared with most other products currently available. The sole exception of course is the Eminent Technology rotary fan subwoofer that costs $13,000 an has an upper bandwith limit of 25Hz. The uniformity of the Conquest dynamic capability exceeds that of any commercial product I've ever measured."

Keith Yates who designs Home Theaters and listening rooms for a living. Who like the best testers did his measurements outdoors ground plane. His "Way Down Deep" test of 12 high performance subs still is very valuable to those who want to see how subs should be tested and how standard bearers like the Genelec HTS-6 actually measure and compare.

You would do well to read his test methodology as well as all the individual reviews to see how closely the test measurements correspond to his rankings.

Here is a link to the test methodology:

http://www.hometheater.com/content/w...st-methodology

Ilkka Rissanen:

Ilkka was so far ahead of you it isn't funny. Like Keith Yates, and Josh Ricci, he knew that outdoor groundplane is the industry standard. Ilkka's body of work is still a reference. The professionalism of his work was such that he was hired by Genelec as an R&D engineer in acoustics.

His work is exemplary and demonstrates the mediocre performance of the XTC 99 W 12, which in the second 2010 CEA chart on the following page has the XTC 99 W 12 ranked 28th (of 41) in Maximum Extension mode, and 33rd (of 41) in Maximum Output mode. Putting it behind subs like the sealed SVS SB-12 Plus, and ported subs like the ported HSU VTF-3.3, and the ported SVS PB-12 NSD.

http://www.hometheatershack.com/foru...mpilation.html

These are just a few of the pros I can discuss.

There are many others who know how to conduct a comprehensive subwoofer review including a bunch of people who post here on AVS.

Meanwhile, please continue learning how to use test equipment to present usefull data on subwoofers while professing that the best subwoofer reviews are 90% subjective and 10% objective...
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post #11 of 32 Old 05-05-2012, 03:26 PM - Thread Starter
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Thanks for proving my point about you. Again. You actually make this very easy for me.

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Originally Posted by spyboy View Post

Your opinion that the best reviews are 90% subjective and 10% objective is way out of line with the better subwoofer testers including professionals like:

You do know what the word "opinion" means, right? It's completely irrelevant whether or not you concur, so there's no value in arguing against it. It's an opinion. Look it up. You'll see what it means.


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Originally Posted by spyboy View Post

Don Keele who designed speakers for JBL. And, he really designed them, not just offering up very minor incremental revisions like adding an addional 8 ounces of poly fill

It was 10 ounces. If you're going to be vain enough to try and mock someone at least know what you're talking about. And ironically, it's way more then you've ever achieved. Like I said, you don't contribute; you merely echo what others have done. Unless you can stand up and be counted on to provide something beyond other peoples opinions then you have no place to judge what someone else has done. Like I said, stop talking and start doing. If you want anyone to believe you're the savant you purport how about proving it in some tangible manner?


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Originally Posted by spyboy View Post

Ilkka was so far ahead of you it isn't funny.

Other then you, who cares? I don't do this for a living, so I would certainly hope he's better at it then me. I'm sure he's far ahead of you too. You're point proves nothing, which is pretty standard it seems.


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Originally Posted by spyboy View Post

Meanwhile, please continue learning how to use test equipment to present usefull data on subwoofers while professing that the best subwoofer reviews are 90% subjective and 10% objective...

I have every intention of it, because unlike you I want to contribute something of value. You continue wasting forum space with useless drivel and personal attacks, designed solely to inflate your immense ego. It's not working though - I'm sure more and more members are seeing through your facade too, so it's probably having the inverse affect.

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post #12 of 32 Old 05-05-2012, 03:29 PM
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^^
Jim's review is from his hobby and I really appreciate him taking time doing it. He does not get paid doing the reviews like others you mentioned. He has a real job too, you know? I enjoy reading his reviews. You do not have to agree with him nor to read his review. Give him a break, man. He was trying to give his opinion to help folks here which is what this forum should be for.
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post #13 of 32 Old 05-05-2012, 03:32 PM
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Opinions are like body parts, everyone has them.
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post #14 of 32 Old 05-05-2012, 04:50 PM
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^^
So what? Jim has his opinion about the subs, I can have mine, you can have your own about the subs. Just don't raise your opinion on other folks' opinion. Can we just try to have fun here?
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post #15 of 32 Old 05-05-2012, 05:56 PM
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Quote:
Originally Posted by JimWilson View Post

In an attempt to have my subwoofer reviews be more objective I decided to make time -- you know how that goes -- to learn how my XTZ Room Analyzer II Pro functions.

Jim, glad to see you got the XTZ to do some measurements in order to do more objective reviews. However, before going further it is important that you understand what is your goal in making your reviews more objective. What data are you trying to present to your reader? This is important because you need to know if XTZ will help you or not in doing that.

From reading the few posts above, it seems that you're really new at this and do not understand:

1. How to take measurements
2. How to read measurements
3. The limitations of XTZ

So at this stage it would be a joke if you tried to add in the XTZ RTA graphs and hope that somehow that makes your review more objective. But everybody needs to start somewhere and you are intent on learning...

Quote:


My first set of measurements have been taken, so I wanted to get some feedback from those who know about measured testing to see if these numbers appear legit. I already have an opinion formulated, now I need to see if the neophytes measurements -- that would be me -- are corroborated by people who know what they're doing.

First thing you have to realize is that it is really difficult for anyone to corroborate what you are doing. How do you expect someone who has never tested or heard those 2 subs to know if your numbers are correct or not, especially with the way you have tested. It is simply an unrealistic expectation for you to get feedback "if these numbers appear legit".

Quote:


For both subs I pointed the mic directly at the center of the driver, exactly 1 meter away. They were at least 1.5 feet from the nearest wall. The room is carpeted.

Was it 1m away? From the photos you later posted the mic appears a lot closer than 1m.

Even if it was 1m away, do you understand how much your room influences the reading? Especially with the nearest wall being only 1.5' away. This is why I said earlier you do not understand how to take a reading.

Quote:


The XTZ software has a meter which denotes clipping so all tests were run up to clipping, then the gain was turned down to just below that point. You only have preconfigured tones you can send out, so the possibilities aren't endless, which is why you'll see gaps between the frequencies. I started at the lowest -- 10Hz -- and stopped at 125Hz, even though I could have gone to 250Hz. 125Hz seemed like a reasonable ceiling to me though, so I'll probably stick to that in the future as well.

Your use of the RTA also demonstrates this. As craig john said you should have used the FR sweep function in XTZ not the RTA.

Quote:


The Rumba 12's numbers look like what it sounded like to my ears, so I'm pretty content with that one. The unidentified sub looks about right too, except for that bizarre dip around 50Hz (which I tested 3 times, just to make sure I wasn't losing it), so I image it's probably pretty accurate as well.

Really? You can tell that the "numbers look like what it sounded like to my ears". Then you're a better man than 99% of the population. Also shows what a high opinion you have of your capabilities.

The dip at 50Hz is the room influence due to the way you have measured.

Quote:


I want to see if I'm doing this properly, or if I need to go back to the drawing board.

You need to go back to the drawing board. There are a number of threads here on AVS and also articles elsewhere on the web that you can refer to. In doing your reading, keep in mind the 3 factors I mentioned earlier:

1. How to take measurements
2. How to read measurements
3. The limitations of XTZ
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post #16 of 32 Old 05-05-2012, 06:09 PM
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Quote:
Originally Posted by tvuong View Post

^^
So what? Jim has his opinion about the subs, I can have mine, you can have your own about the subs. Just don't raise your opinion on other folks' opinion. Can we just try to have fun here?

Indeed Jim has his opinion. But he is now in a different position than your average Joe - he has made a bit of a name for himself as a reviewer of budget subs and is moving to more expensive subs. Sub manufacturers are now approaching him to get him to do reviews. Jim is also thinking how he can derive some income in future doing this... he's thinking of going pro.

I'm sure Jim enjoys the status, but with that status or position it also behooves Jim to render properly informed opinions.
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post #17 of 32 Old 05-05-2012, 06:12 PM
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Quote:
Originally Posted by JimWilson View Post

Alright, let's try this again... I attached a few pictures of how I mic'ed the Rumba 12, along with a graph created using the pink noise generator.

I hope you're aware that a pink noise generator isn't the way to go about it.
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post #18 of 32 Old 05-05-2012, 06:44 PM - Thread Starter
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Quote:
Originally Posted by jchong View Post

So at this stage it would be a joke if you tried to add in the XTZ RTA graphs and hope that somehow that makes your review more objective. But everybody needs to start somewhere and you are intent on learning...

"joke" is harsh at best, and uncalled for at worse. This thread was intended to get an understanding of how the product functions, and to solicited legitimate (key word) advice from those who are more familiar with the process. I want to fully understand what I'm posting in a review before I post it. That's how it's supposed to work, right?


Quote:
Originally Posted by jchong View Post

First thing you have to realize is that it is really difficult for anyone to corroborate what you are doing. How do you expect someone who has never tested or heard those 2 subs to know if your numbers are correct or not, especially with the way you have tested. It is simply an unrealistic expectation for you to get feedback "if these numbers appear legit".

I know. That's precisely why I said "I realize without having actually heard the subs yourself you can't make a definite assessment, but in general how do they fair?".


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Originally Posted by jchong View Post

Was it 1m away? From the photos you later posted the mic appears a lot closer than 1m.

At least you have a point on this one. Those photo's were taken after I got some worthwhile (read: constructive) assistance from someone on another forum. They suggested I move the mic closer, which consensus indicated was the preferred method for indoor readings.


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Really? You can tell that the "numbers look like what it sounded like to my ears". Then you're a better man than 99% of the population.

From where did you get this 99% figure from? Something credible, or purely fictional?


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Also shows what a high opinion you have of your capabilities.

Seems to be a lot of that going around.

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post #19 of 32 Old 05-05-2012, 06:55 PM - Thread Starter
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Originally Posted by jchong View Post

Jim is also thinking how he can derive some income in future doing this... he's thinking of going pro.

No he's not, that's why there was a smiley after that statement. This is a passion of mine, not a career. If it continues to grow then I may see if there's a way to be compensated for my time, but there will be nothing beyond that. My chosen profession is one I have no intention of leaving.


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Originally Posted by jchong View Post

I'm sure Jim enjoys the status, but with that status or position it also behooves Jim to render properly informed opinions.

There seems to be an abundance of people who don't comprehend what opinion means. To clarify, it's "a personal view, attitude, or appraisal". I've done nothing but render properly informed opinions, but since opinions are purely subjective how could anyone's not be?

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post #20 of 32 Old 05-05-2012, 07:01 PM
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Quote:
Originally Posted by JimWilson View Post

I've done nothing but render properly informed opinions, but since opinions are purely subjective how could anyone's not be?

When one's opinion contradicts someone else's opinion, one's opinion is clearly not "properly informed".

But, y'know, that's just my opinion.


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post #21 of 32 Old 05-05-2012, 07:12 PM
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Quote:
Originally Posted by JimWilson View Post

"joke" is harsh at best, and uncalled for at worse. This thread was intended to get an understanding of how the product functions, and to solicited legitimate (key word) advice from those who are more familiar with the process. I want to fully understand what I'm posting in a review before I post it. That's how it's supposed to work, right?

Harsh it was and it was intended to sound that way. Like I said at this stage it would be a joke given your current level of understanding. Posting an RTA based on pink noise... ever seen such a thing in a sub review?

Yes you can solicit advice but before that I hope you have done quite a bit of reading first. Otherwise it appears as if you're asking the forum to do your homework for you.

Quote:


I know. That's precisely why I said "I realize without having actually heard the subs yourself you can't make a definite assessment, but in general how do they fair?".

Still not a fair question to ask in my opinion because you'll not get an accurate reply.

Quote:


At least you have a point on this one. Those photo's were taken after I got some worthwhile (read: constructive) assistance from someone on another forum. They suggested I move the mic closer, which consensus indicated was the preferred method for indoor readings.

Again, this goes back to my comment about not doing your homework. You should have done a lot of reading on measurement methodology prior to this. If you were an average Joe complete noob it would be understandable, but you have positioned yourself better than this so this is why I'm perhaps harder on you.

The 1m distance is standard for outdoor ground plane measurements (even though 2m seems to be preferred nowadays). For indoor you need a close mic measurement, which is only a few inches away as what you later found out. If you have a ported sub the mic position also needs to be adjusted a bit to account for the port.

The close mic technique would not give the full picture when it comes to the sub with the passive radiators because the contribution of the radiators is not taken into account. Therefore, your interpretation of the results would not be correct.

Again I ask: do you know what performance metric you are trying to convey by including XTZ graphs in your review? Then following from that is XTZ even suitable for the goal you have in mind?

Quote:


From where did you get this 99% figure from? Something credible, or purely fictional?

It was a rhetorical 99% in case you didn't get that. And you didn't answer the part about "Really? You can tell that the "numbers look like what it sounded like to my ears"." If you truly believe you have that ability then this is one example where you have a high opinion of yourself.

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No he's not, that's why there was a smiley after that statement. This is a passion of mine, not a career. If it continues to grow then I may see if there's a way to be compensated for my time, but there will be nothing beyond that. My chosen profession is one I have no intention of leaving.

Ok, going part-time pro then. Or moonlighting. But if you intend to be compensated for your time then you're not just an average Joe giving his opinion.

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There seems to be an abundance of people who don't comprehend what opinion means. To clarify, it's "a personal view, attitude, or appraisal". I've done nothing but render properly informed opinions, but since opinions are purely subjective how could anyone's not be?

I get what opinion means, but some people's opinions are worth more than others right? Even experts can have different opinions but each can back up their opinion with their own research and data and experience.

Yes an opinion is personal or subjective, but behind that subjectivity is knowledge and experience. Hence an opinion from someone who is knowledgeable and experienced is different from an opinion from someone who is not. So really what we'd like to know is what is your knowledge and experience with subs so we know how much weight and credibility we can give to your opinion.
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post #22 of 32 Old 05-05-2012, 07:42 PM - Thread Starter
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Harsh it was and it was intended to sound that way. Like I said at this stage it would be a joke given your current level of understanding.

Bottom line, you need to maintain some degree of decorum. You want to say that the graphs wouldn't be appropriate to post now? Then say it without being so disrespectful. Otherwise your comment is nothing more then a joke itself, and does nothing to help.


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Yes you can solicit advice but before that I hope you have done quite a bit of reading first. Otherwise it appears as if you're asking the forum to do your homework for you.

The first paragraph says "I've read the manual twice now". The very last thing I would do is not research something before asking a question. Frankly, I take it to the extreme instead. But at some point you have to take the plunge, jump into the pool and start swimming; you just can't keep reading about it.

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post #23 of 32 Old 05-05-2012, 07:47 PM - Thread Starter
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Originally Posted by eljaycanuck View Post

When one's opinion contradicts someone else's opinion, one's opinion is clearly not "properly informed".

But, y'know, that's just my opinion.

Do you even know what that's supposed to mean?

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post #24 of 32 Old 05-05-2012, 08:32 PM
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Do you even know what that's supposed to mean?

I do!


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post #25 of 32 Old 05-05-2012, 09:04 PM
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Bottom line, you need to maintain some degree of decorum. You want to say that the graphs wouldn't be appropriate to post now? Then say it without being so disrespectful. Otherwise your comment is nothing more then a joke itself, and does nothing to help.

The comment itself might have been disrespectful or harsh but certainly not a joke. And that comment was only one sentence in a long post... it was not meant to help but rather express an opinion.

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The first paragraph says "I've read the manual twice now". The very last thing I would do is not research something before asking a question. Frankly, I take it to the extreme instead. But at some point you have to take the plunge, jump into the pool and start swimming; you just can't keep reading about it.

I'm not talking about merely reading the manual twice. The manual itself only talks about the XTZ product and how to use it.

How about reading about measurement methodology in general (the theory and science behind it). Then you would have known what was the appropriate distance to place the mic. What about where to place the sub in room?

How about reading about the different graphs and what they represent? Then you would have known the RTA is not appropriate and the frequency sweep is more relevant.

But you haven't even addressed the most critical issue: what performance metric are you trying to convey by including XTZ graphs in your review?

Yes, I'm being hard on you. You project yourself as a capable sub reviewer, a sub "designer" even... and with that comes a bit of ego/pride that you know what you're doing. In my opinion that ego/pride needs to be knocked back a little so you can really start learning about this stuff and become even better. There's a lot of people who are willing to help and share. Anyway, enough with getting personal. Just gets more feathers ruffled without achieving anything. So let's start over with my question: what performance metric are you trying to convey by including XTZ graphs in your review?
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post #26 of 32 Old 05-06-2012, 08:16 AM
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Thanks for proving my point about you. Again. You actually make this very easy for me.



You do know what the word "opinion" means, right? It's completely irrelevant whether or not you concur, so there's no value in arguing against it. It's an opinion. Look it up. You'll see what it means.




It was 10 ounces. If you're going to be vain enough to try and mock someone at least know what you're talking about. And ironically, it's way more then you've ever achieved. Like I said, you don't contribute; you merely echo what others have done. Unless you can stand up and be counted on to provide something beyond other peoples opinions then you have no place to judge what someone else has done. Like I said, stop talking and start doing. If you want anyone to believe you're the savant you purport how about proving it in some tangible manner?

My statement says that in




Other then you, who cares? I don't do this for a living, so I would certainly hope he's better at it then me. I'm sure he's far ahead of you too. You're point proves nothing, which is pretty standard it seems.




I have every intention of it, because unlike you I want to contribute something of value. You continue wasting forum space with useless drivel and personal attacks, designed solely to inflate your immense ego. It's not working though - I'm sure more and more members are seeing through your facade too, so it's probably having the inverse affect.

If you read my post correctly you would see that I said that your great contribution was to come up with using AN ADDITIONAL 8 ounces of polyfill which comes to 10 ounces, since the Rumba originally had 2 ounces of polyfill. Further, it took 2 people to decide that 10 ounces of polyfill was the ideal amount. That is some heavy duty "design" work you are doing

Good thinking about not leaving your day job to test subwoofers. After all, despite the fact that it is widely known that if you are not testing outdoors groundplane your aren't in the big leagues.
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post #27 of 32 Old 05-06-2012, 03:02 PM - Thread Starter
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The comment itself might have been disrespectful or harsh but certainly not a joke. And that comment was only one sentence in a long post... it was not meant to help but rather express an opinion.

It was perhaps a single sentence, but the entire tone of that post -- and every subsequent one from you -- has been similar. What possible help is derived from being arrogant and disrespectful? None. Don't try and fool yourself, or me for that matter, into thinking you've done anything even remotely close to helping.


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How about reading about measurement methodology in general (the theory and science behind it). Then you would have known what was the appropriate distance to place the mic.

I have read many other sub reviews and articles on how to obtain measurements. But there is significant contradictory viewpoints on what's the best method, so I posted for advice. That's what these forums are supposed to be about, aren't they?


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Yes, I'm being hard on you. You project yourself as a capable sub reviewer, a sub "designer" even... and with that comes a bit of ego/pride that you know what you're doing. In my opinion that ego/pride needs to be knocked back a little so you can really start learning about this stuff and become even better.

I've never projected myself as anything other then someone giving an opinion of a sub. Period. And regardless of how you misinterpreted my contributions, who the h#ll are you to decide that someone needs to be "knocked back"? I'd get outright banned for telling you what I'd like to about that utterly asinine statement, so I'll just leave it with this: stop trying to "help" me. You clearly have no intentions of anything other then being belligerent, so it's time for you to go "help" someone else. Actually, it's long overdue.

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post #28 of 32 Old 05-06-2012, 03:05 PM - Thread Starter
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If you read my post correctly you would see that I said that your great contribution was to come up with using AN ADDITIONAL 8 ounces of polyfill which comes to 10 ounces, since the Rumba originally had 2 ounces of polyfill. Further, it took 2 people to decide that 10 ounces of polyfill was the ideal amount. That is some heavy duty "design" work you are doing

And you've contributed to making a product better when? How? Not at all would be my guess. Got you beat there. Again.

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Good thinking about not leaving your day job to test subwoofers. After all, despite the fact that it is widely known that if you are not testing outdoors groundplane your aren't in the big leagues.

At least I'm in the game, and not sitting on the side lines doing nothing but whining. Real helpful you are.

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post #29 of 32 Old 05-06-2012, 06:14 PM
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I have read many other sub reviews and articles on how to obtain measurements. But there is significant contradictory viewpoints on what's the best method, so I posted for advice. That's what these forums are supposed to be about, aren't they?

Regarding in-room sub measurements the general consensus is that a close mic reading should be taken. I've not read significant contradictory viewpoints on this. However, there have been contradictory viewpoints on the usefulness or validity of in room measurements per se.

Like I said, it is fine to post questions and ask for advice. But one additional layer is that you'd like for that advice to be delivered to you all nice and sweet.

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I've never projected myself as anything other then someone giving an opinion of a sub. Period.

True to some extent but do note you have projected yourself as being involved in sub design and contributing to some engineering changes in a sub. But I'm not just talking about the outward act of you giving an opinion. Internally you like to think of yourself as someone who writes sub reviews well. I've seen your reviews and they are quite detailed and well written. I'm sure you take pride in that. When people compliment you on your reviews you're happy.

Having done some reviews, maintaining the thread on budget subs, being recognized by some manufacturers and being submitted subs for review... all these make you feel good, that you are progressing. Perhaps you even think to yourself "hey I'm getting pretty good at this". Your responses to spyboy show your pride in being in the game.

So now you want to take it to another level, by including some graphs into your review. Once you start doing that, it becomes less subjective and more objective. You have to be clear on what you're doing. Look at your first post in this thread - the first few paragraphs you talk about what you've done in terms of measurements. The tone of it suggests that you proceeded quite confidently in terms of methodology - the main thing you wanted was "to get some feedback from those who know about measured testing to see if these numbers appear legit. I already have an opinion formulated..."

Again this is echoed towards the end: "Do these numbers look as though they could be legit to you? I realize without having actually heard the subs yourself you can't make a definite assessment, but in general how do they fair?"

You're just asking for validation on the numbers and how do the subs fare. It seemed like you assumed you did everything right and you were more interested in the results. You never did ask if your methodology was correct except obliquely in your last sentence. So when you were being challenged on this perhaps it bruised your pride... so you became defensive.

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And regardless of how you misinterpreted my contributions, who the h#ll are you to decide that someone needs to be "knocked back"? I'd get outright banned for telling you what I'd like to about that utterly asinine statement, so I'll just leave it with this: stop trying to "help" me. You clearly have no intentions of anything other then being belligerent, so it's time for you to go "help" someone else. Actually, it's long overdue.

That's your ego/pride talking right there. When something less than positive or complimentary is pointed out to you, you get all defensive. Instead of addressing the substantive matters you attack on the form. You have communicated clearly your dislike of my style or tone in responding to you but you have not responded on the substantive question I asked - I suspect that is because you do not know and you do not wish to admit that. I also think you do not like being challenged.

And please, if you're being so picky on everything I write, I did not say that you have to be knocked back, it was your ego/pride.

Was it not you who came here asking for help? However, when help was given you don't seem to appreciate it. craig john pointed out it was better to use the FR graph and 2D waterfalls - helpful advice but you didn't respond to that.

Anyway, I wish you good luck on your endeavours.
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post #30 of 32 Old 05-06-2012, 08:09 PM - Thread Starter
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Like I said, it is fine to post questions and ask for advice. But one additional layer is that you'd like for that advice to be delivered to you all nice and sweet.

Civility is a "layer" for you? That's scary. Who honestly wants sarcastic, useless BS being pawned off as "advice"? Do you answer everyone that sardonically? If so then you've never helped a single person.


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Having done some reviews, maintaining the thread on budget subs, being recognized by some manufacturers and being submitted subs for review... all these make you feel good, that you are progressing. Perhaps you even think to yourself "hey I'm getting pretty good at this". Your responses to spyboy show your pride in being in the game.

How how on earth do you even have the slightest clue about how I view things? You've proven, quite categorically, the exact opposite. Save your two-bit psychology lessons for someone who isn't able to see through your transparent ploy.


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Look at your first post in this thread - the first few paragraphs you talk about what you've done in terms of measurements. The tone of it suggests that you proceeded quite confidently in terms of methodology - the main thing you wanted was "to get some feedback from those who know about measured testing to see if these numbers appear legit. I already have an opinion formulated..."

My "tone" -- assuming there really is one -- suggested nothing of the kind, so this is yet another thing you completely missed the mark on. So I guess in your mind me asking if the neophytes measurements could be corroborated by someone who knows what they're doing somehow got twisted into an exclamation of confidence? I don't even want to know how you got from point A to point B with that one.


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You're just asking for validation on the numbers and how do the subs fare. It seemed like you assumed you did everything right and you were more interested in the results. You never did ask if your methodology was correct except obliquely in your last sentence. So when you were being challenged on this perhaps it bruised your pride... so you became defensive.

Are you ever going to get any of your wild guesses right? As is your wont, the assumption is completely and totally wrong. The last paragraph is not ambiguous in the slightest, providing you take the time to read it and not read into it.


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That's your ego/pride talking right there.

Ego talking? Now there's something you know all too well, because that's what you've done since you began to pollute my thread; feed your ego trip. And let's be clear; that's all it's been. It's so blatantly obvious even Stevie Wonder could see that.


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When something less than positive or complimentary is pointed out to you, you get all defensive.

"less then positive"? That's what you call caustic and deliberately inflammatory comments? Wrong. Again. I react negatively to disrespectful, arrogant people. When someone acts like you do I respond like this, it's just that simple. When I'm attacked for no reason I respond in like kind. You get what you give. Less then positive. Cut me a break...


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Was it not you who came here asking for help? However, when help was given you don't seem to appreciate it. craig john pointed out it was better to use the FR graph and 2D waterfalls - helpful advice but you didn't respond to that.

What question did he ask? He posted a suggestion -- a real one -- about what might be a better way to approach this. I was going to try his suggestion and post back, but you and the other one have destroyed this thread to the point where it's no longer a possibility. BTW, thanks for your wonderful "help" with that - it turned out to be worthless too.

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