|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
In Reply to: Re: Give us a break Brian. posted by Brian Cheney on July 30, 2002 at 10:44:42:
Well Brian, I did not say you were full of it.I was not implying anything like that either.
But, I still have a hard time understanding why you stated, and now why you animately attempt to justify the need for maintaining unobtainable tolerances in your capacitors, especially in light of such greater discrepancies that are possible and common in other areas with much greater effect.
Also I find it hard to believe that you go to such extreme to maintain high QC regarding driver consistency as well yet could care less how one of your speakers has measured once it has left your shop (regarding the rather lengthy threads on the Mad board).
If any of my speakers measured with the 30db response dip and other problems that I saw posted of one of your speakers, I would be concerned. I would likely think something to be seriously wrong and I would be doing all I could to remedy the situation.
I am also not really sure what you meant when you related your experience measuring the Spica TC 60's?
Are you trying to say that despite your best efforts you could not produce a flat response with it as well?
Or are you saying that it sounded good despite the poor measurements? You did not mention how it sounded.
What was the point of that portion of your reply?
Follow Ups:
Danny, you should know better than to ask these questions.The tolerances I mention are not only obtainable and maintainable, I have been trimming every crossover to such tolerances for over 15 years. I understand if you don't care about tolerances, or can't hear the difference between the correct crossover point and the wrong one. I surely wouldn't advertise such a personal shortcoming on a forum like this, however.
I have total control over every aspect of the design and manufacture of our speakers. I can and do what I want. It is not your place to question why, as it would not be my place to critcize what you do. Why anyone would try to put such as highly regarded product as mine in a bad light is beyond me.
As for 30 dB notches and the like, I will assume tester incompetence.
The Spica story illustrates that when you measure speakers you have to put your mic where it measures best, not worst, even if that takes some doing.
"The tolerances I mention are not only obtainable and maintainable,"Tolerances that you are boosting can only be maintained for the mere moment you measure them. After that they will change. Those tolerances will change considerably after they have been burned in. Temperature will shift them. Plus, caps often short. It's a self healing process, but it will easily shift the value by more than the tolerance percentage you are shooting for. Dr.J even mentioned it could shift that much just from holding it in your hand. Considering he designs caps I wouldn't doubt it.
"I understand if you don't care about tolerances"
Oh I certainly do. I measure every driver that is sent out from here. Even our inexpensive $24.95 soft dome tweeters have a response curve of that tweeter attached to each one that leaves. I also measure each fully assembled speaker that leaves here as well.
The crossover components I use are generally better than 2%. If someone would like them even closer I can measure a few of them and pick some out that are better than 1%.
Even you just stated that your coils are held to only 1% tolerances.
Your resistors won't fall within 1% tolerances. Most are no better than 5% and still considered within specs.
If you are using some kind of variable L-pad (and it sounds like you are) the customer will never be able to turn them to the same setting twice or even come close to matching them to the cap tolerances you are claiming. They can be off more than 1% from one speaker to the next and the audible difference will not be heard. It can't be. The input isn't the same. Most of the time a completely different signal is sent to the right and left speakers.
When measuring a speaker it is to subjective to determine if the tweeter response looks better with a 6.800uF cap on it or a 6.9uf or a 6.7uF cap. It may make less than 1/10th of a db difference in the response curve. Moving the mic (or you ear) up or down 2" will make more difference.
"It is not your place to question why, as it would not be my place to criticize what you do."Oh, I don't question why you do it. I am not criticizing your actions in any way. I really don't care if you go to the effort or not. But, I am really surprised that you advertise it and expect well educated and knowledgeable members of the industry to see any value in trying to hold cap tolerances that close. I am certainly not the only one here that can't believe you are making such claims.
"Why anyone would try to put such as highly regarded product as mine in a bad light is beyond me."
No one, absolutely no one here, has said a single bad or negative thing about any of your products. In fact even those that are questioning your claims here about capacitor tolerances have had nothing but good things to say about your products. I also feel as if you are offering a good quality product for a really good price and I have no doubt it stands above the norm.
"The Spica story illustrates that when you measure speakers you have to put your mic where it measures best, not worst, even if that takes some doing."
This is also a completely ridiculous statement.
Do you also put your ear where it measures best too?
You should have a targeted design axis in the beginning before you even take the first measured response. You should never design a crossover then begin taking response measurements in different locations searching for the best response.
Personally I measure all our speakers in what I feel is listening axis or what might be ear level. Even our inexpensive kits are all within about a +/-2db range and most often than not measure smoother than that. Some have measured as good as +/-.75db.
Response measurements are posted on all our kits.
I also measure off axis response in the vertical and horizontal plane and post those responses too. This will give a better indication of what the room response might be.
"As for 30 dB notches and the like, I will assume tester incompetence."
Brian, I know the guy that took the measurements. It was taken at an ear level height. There were also several other speaker measured along with yours. This guy is VERY competent.
That was not it.
You are embarrassing yourself with an endless litany about how you measure speakers. I don't care how you measure and your measurements are of the crudest sort. You lack the training and ability to discern small but vital sonic differences and you seem determine to apply your own low standards to everyone else.Let's wait until your have my press clippings and professional recognition before you even question what I do or how I do it.
And yes, the RM 1 was measured incompetently if done in the manner you describe. The people involved should be ashamed of themselves.So should you.
"You are embarrassing yourself with an endless litany about how you measure speakers."If anyone is looking or feeling a little embarrassed here it is certainly not me.
"I don't care how you measure and your measurements are of the crudest sort. You lack the training and ability to discern small but vital sonic differences and you seem determine to apply your own low standards to everyone else."
A personally attack on me will not help you here. You also do not know me well enough to judge my training or ability.
And I mentioned my measurements because you said I didn't care about tolerances. I was in no way comparing my standards to yours.
"And yes, the RM 1 was measured incompetently if done in the manner you describe. The people involved should be ashamed of themselves."
Maybe you could tell us how that speaker should have been measured? If ear level is not the design axis then what is it? Please let us know?
"So should you."
I have nothing to be ashamed of. I have only asked you some questions, as have others. I think all here have been more than civil to you as well. It seams that only you have become offensive and have made personally attacks.
You have not answered anyones questions here and you are digging yourself into a hole. Maybe you should just stop now. It is getting pretty deap.
This post is made possible by the generous support of people like you and our sponsors: