Are Speaker Manufacturers just "optimistic" ? |
Post Reply | Page 123 4> |
Author | ||
Hemisphere
Old Croc Joined: 21 April 2008 Status: Offline Points: 2272 |
Post Options
Thanks(0)
Posted: 14 August 2017 at 6:34pm |
|
|
||
Racks&Stacks
Registered User Joined: 10 February 2006 Location: Germany Status: Offline Points: 204 |
Post Options
Thanks(0)
|
|
Pat Brown in the US is at least one of the credible speaker testers. If he or any other were to be willing to fudge the results so that some company with money to throw around would get better results, his client list would soon shrink when it would be realized that they are wasting their time with him. Production Partner is at least one trade magazine which publishes their own test results of various products, sometimes deviating quite a bit from manufacturers claimed specs Some brands get away with it, because their name alone is enough to win a bid, or because they almost give away systems to certain operators and those towards the bottom of the market want to compete and get the same caliber of acts to play on them
|
||
MattStolton
Old Croc Joined: 04 September 2010 Location: Walthamstow Status: Offline Points: 4234 |
Post Options
Thanks(0)
|
|
Even if there was a series of "independent" test houses, deemed to be virtuous and proper, eventually, after working for a manufacturer for a few years, they would get a phone call from manufacturer's marketing dept.:
"Hi Bob. These test results. Look a bit weak. Any danger of just improving them a bit. If you do, I will carry on sending my stuff to you, and paying your invoices. If not, A.N. Other test house has said they will test my stuff for 10% less than you charge, and report back the specs I want...." There already are test centres for BS5839pt8/EN54-24 compliance. So if your Penton or Toa, and you want to certify your speaker as VA compliant (which is mostly physical, i.e. thermal fuse, ceramic connector block, etc) you can, but they also give enough acoustic data to give meaningful EASE type data. So it does exist, but costs a fortune. When doing VA, generally part of the contract talks about meeting 0.5 or 0.6 or higher RASTI or STI, if the client reckons it sounds crap, you get someone in to test system to get a test measurement, and if you fail, you pay for testing, and doing whatever it takes to meet STI, and subsequent remeasure! So accurate speaker data, in the 100V line VA market is already standard, for EN54 compliant systems. But, and it is a big but (and I cannot lie...) VA is life critical. And the systems are big and expensive. So BS is not accepted. Sticking a couple of Eons on sticks is not life critical. So the BS that all other manufacturers spout is marketing "re-interpretation" of measurements to help shift boxes. Thankfully, good manufacturers will balance marketing BS with risk to reputation. Most multi $XXXXX boxes/systems will come with some sort of modelling data, and easy enough to measure result. If the two don't match up, someone pays. At the arse end of the market, what DJ is going to measure his boxes output in any meaningful way, against claim by manufacturers - they will either be loud enough or not. So manufacturers get away with it, especially to those who see big numbers (PMPO, Peak SPL or whatever) and hand over money accordingly. The problem is, most get away with it, as we don't measure, and we suffer a touch of Emporer's new clothes syndrome.
|
||
Matt Stolton - Technical Director (!!!) - Wilding Sound Ltd
"Sparkius metiretur vestra" - "Meter Your Mains" |
||
Hemisphere
Old Croc Joined: 21 April 2008 Status: Offline Points: 2272 |
Post Options
Thanks(0)
|
|
I think that's just to help reinforce the branding with crack addict stereo thieves. 'Kraco! Guaranteed to pawn for at least the price of your next rock!'
|
||
_djk_
Old Croc Joined: 23 November 2004 Location: United States Status: Offline Points: 6002 |
Post Options
Thanks(0)
|
|
|
||
djk
|
||
Hemisphere
Old Croc Joined: 21 April 2008 Status: Offline Points: 2272 |
Post Options
Thanks(0)
|
|
Krakatoa would be a great name for a car audio manufacturer.
|
||
VECTORDJ
Young Croc Joined: 11 June 2006 Location: United States Status: Offline Points: 515 |
Post Options
Thanks(0)
|
|
Liars. Maybe we should file a class action suit against the companies that lie on their specs. Pro audio is starting to look like the car audio fools. I have had many young car stereo customers tell me their 10 or 12 inch sealed box woofer puts out 168 to 170 dB.
|
||
Ricci
Registered User Joined: 13 March 2017 Location: Louisville, KY Status: Offline Points: 69 |
Post Options
Thanks(0)
|
|
Sure...I do it all the time. I think you're underestimating the amount of time needed though. About 6 is my record for # of speakers tested in one day. That was about 16hrs including setup and tear down. Frequency response and / or sensitivity are quick and easy once the setup is assembled and calibrated. Max SPL is much more involved and time consuming especially if it is a passive cab. The thing is you need the whole array of measurements, not just one or two. Personally I need to get all of the data collected at the time the equipment is setup, not just max SPL or voltage sensitivity, so it ends up taking a lot of time for each system. Typically around 2hrs per cab. In my opinion the following group of measurements provide a good characterization of the behavior of a speaker. This is exactly what I do, but of course I'm a bit of a measurement junkie. I'd expect that some manufacturers do similar, if somewhat different, testing to verify and prove out a design. Others likely do much much less. Impedance curve (for passive cabs) Voltage sensitivity (for passive cabs) On axis frequency response Polar data (Not required for subs) Time domain response / group delay / decay plot Output compression plots at increasing drive level ( For subs) Distortion data Short term maximum SPL at each 1/3rd octave band down to at least the -10dB extension rating of the speaker. Raw speaker driver ratings are also a problem at times. The usual problem specs are xmax, power handling and sensitivity. Car audio brands are the worst as a whole. I swear their power handling specs are often just made up completely. Thankfully there is a CEA-2031 spec covering mobile audio that is attempting to bring some reality into the market. Edited by Ricci - 11 August 2017 at 8:36pm |
||
Hemisphere
Old Croc Joined: 21 April 2008 Status: Offline Points: 2272 |
Post Options
Thanks(0)
|
|
So long as the results are consistent and representative, and could be reliably used to compare one product with another, are the merits of the specific methods used that important? Kind of a McDonald's approach to measurements. Low quality but high consistency and fast delivery.
Edited by Hemisphere - 11 August 2017 at 3:38pm |
||
Hemisphere
Old Croc Joined: 21 April 2008 Status: Offline Points: 2272 |
Post Options
Thanks(0)
|
|
Yes.
|
||
Racks&Stacks
Registered User Joined: 10 February 2006 Location: Germany Status: Offline Points: 204 |
Post Options
Thanks(0)
|
|
Wait, are we discussing driver or cabinet specs?
|
||
DMorison
Old Croc Joined: 14 March 2007 Location: Aberdeen Status: Offline Points: 1649 |
Post Options
Thanks(0)
|
|
Ivan Beaver of Danley has posted several times about finding exactly the same issues. Apparently they used to quote one of their boxes as 6Ω, being the most accurate representation of its impedance. But, they were constantly plagued with "how do I find an amp that can drive 6Ω" type questions. Their solution - change the spec sheet to say 4Ω. No stupid questions any more, they still show the Impedance curve on the spec sheet for anyone who really wants to check it for themselves, but anyone who just wants the "simple number" gets told a number that will result in them not overloading their amp by paralleling too many boxes. |
||
Post Reply | Page 123 4> |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |