Get Free, Friendly, Expert Advice
Call 1-866-244-8796 or email

Designed and Manufactured in Canada Since 1980


AxiomAudio Blog

Axiom’s Newest Speaker: The In-Ceiling M3

Outdoor Speaker Placement

Speaker Placement: Unusual Room Layouts and Elevating Speakers

Wall'O'Fame
Greetings fellow Axiom owners...
HG Rosewoods Part 3
Who's Online
1 registered (CV), 149 Guests and 3 Spiders online.
Key: Admin, Global Mod, Mod
Financing
Forum Stats
13303 Members
11 Forums
22841 Topics
403596 Posts

Max Online: 378 @ 02/24/13 04:33 PM
Top Posters
Ken.C 17751
pmbuko 16267
SirQuack 13321
CV 11160
MarkSJohnson 10848
Meanwhile On Facebook

Get a Gift Card Worth 20% of Your Purchase! Save hundreds!

Got your new In-Ceiling speakers yet? #atmosready http://axiomaudio.com/m3-in-c...

(y) Can't wait for the next evolution of surround sound to go mainstream!

Pre-order our new in-ceiling speakers and save 25%! Offer ends August 11th.

Page 3 of 4 < 1 2 3 4 >
Topic Options
Rate This Topic
#146451 - 09/03/06 04:31 PM Re: What on earth is Ian up to now? [Re: n8wrl]
jakeman Offline
aficionado

Registered: 10/03/05
Posts: 852
Loc: Toronto
Well after several good conversations with Ian, Tom, Alan and Amie we went out back to look at the testing tower. Its always very pleasant spending time with them and getting caught up.

The tower sure looks like a good 100 ft up close. I had hoped to see a sub being tested but the wind had been picking up since early Friday morning as Ernesto continued its course up the East Coast. Nevertheless I did get a demonstration about the testing procedure.

Here is a shot of the weather instrumentation which goes up before every test. The temperature, humidity, barometric and wind readings are transmitted wirelessly to a metre inside the plant.



The environmental guidelines for successful testing seem to be temperature at no less than 10C, low to no wind, and average humidity. Humidity was not a factor I had given much thought too but apparently a high humidity testing environment can have an impact on results. I want to think about that one as it implies high water content in the air can affect wave propagation.

You can't see it in the above picture but there is a wire about 6ft over the platform which runs parallel. A Bruel & Kjaer mic is suspended over the sub or speaker equidistant from its drivers and ports. The mic can be moved along the wire depending on the subs configuration. Why a B & K mic? Its known to be one of the most accurate mics made and at $5,000 each it better be.



Anyway because of the wind, we just hoisted up the instrument cluster. The procedure was simpler than I thought. No winch. There is a pulley on top of the tower and another at the bottom. The platform is lifted by a 3/8" steel wire which is connected to a golf cart by a hook. Driving the cart backwards raises the platform to the desired height. The cart driver looks familiar.





The long distance of the tower requires a power boost and as a result of 100db appears to be the limit of reliable measurements. That's too bad as I look forward to seeing graphs at max output to get a better idea of the subs behaviour under stress. Perhaps a small generator at the tower itself would help matters. Here is a shot of the platform being lifted along with the electrical wires.


This finicky attention to detail and R & D just impresses the hec out of me.
_________________________
John

Top
#146452 - 09/03/06 06:54 PM Re: What on earth is Ian up to now? [Re: jakeman]
Ajax Offline
axiomite

Registered: 12/30/03
Posts: 6248
Loc: Cleveland, Ohio
Quote:

Humidity was not a factor I had given much thought too but apparently a high humidity testing environment can have an impact on results. I want to think about that one as it implies high water content in the air can affect wave propagation.



May I then suggest you never build a tower and take measurements in Cleveland, Ohio. 56% today, and it's a "dry" day.
_________________________
Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton

Top
#146453 - 09/03/06 07:21 PM Re: What on earth is Ian up to now? [Re: Ajax]
jakeman Offline
aficionado

Registered: 10/03/05
Posts: 852
Loc: Toronto
Yes humidity is a bigger factor than I thought even in Cleveland. Knowing temperature and humidity you could use adjustment tables to get to a reference. As the air get moister, it becomes less dense(reverse of what I thought at first) and the speed of sound increases. It can make quite a difference to FR measurements or phase. I'm also wondering if that explains why my equalization settings appear miscalibrated on high humidity days.
_________________________
John

Top
#146454 - 09/04/06 12:21 AM Re: What on earth is Ian up to now? [Re: jakeman]
Ajax Offline
axiomite

Registered: 12/30/03
Posts: 6248
Loc: Cleveland, Ohio
Does this mean there is an equalizer with a humidity sensor in our future?
_________________________
Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton

Top
#146455 - 09/04/06 01:44 AM Re: What on earth is Ian up to now? [Re: Ajax]
bridgman Offline
axiomite

Registered: 08/25/04
Posts: 5330
Loc: Bowmanville, Ontario, Canada
Good idea. I was about to buy a humidor for the box of Cohibas my brother-in-law brought back from Cuba -- maybe I'll hold off until I can get a combination humidor / BFD. Why buy two hygrometers when you can share one between the humidor and the PEQ ?

Top
#146456 - 09/04/06 10:16 AM Re: What on earth is Ian up to now? [Re: Ajax]
jakeman Offline
aficionado

Registered: 10/03/05
Posts: 852
Loc: Toronto
Quote:

Does this mean there is an equalizer with a humidity sensor in our future?




I guess it means you should look at humidity as much as temperature. Ideally equalize on a day with "normal" temp and humidity in your room.

I like John's idea. Smoke a Cohiba and if tastes too moist, go listen to tunes instead.
_________________________
John

Top
#146457 - 09/04/06 10:27 AM Re: What on earth is Ian up to now? [Re: bridgman]
jakeman Offline
aficionado

Registered: 10/03/05
Posts: 852
Loc: Toronto
If you are so inclined here is a good article from AES on just how much these two factors can effect sound especially phase in a room. One conclusion is that it questions the usefulness of the auto-equalization feature found in many receivers.

http://www.rane.com/pdf/eespeed.pdf#search="environmental%20effects%20on%20the%20speed%20of%20sound"
_________________________
John

Top
#146458 - 09/04/06 11:53 AM Re: What on earth is Ian up to now? [Re: jakeman]
Ajax Offline
axiomite

Registered: 12/30/03
Posts: 6248
Loc: Cleveland, Ohio
Quote:

Ideally equalize on a day with "normal" temp and humidity in your room.



LOL! The humidity in my room (I have a humidity measuring thingy) is "normally" around 20% in the winter (forced air heat), and during the summer "normal" varies from 30 to 75% (Just a slight variation. ), depending on whether it's the Gulf of Mexico sending us our weather, or if it's Cananda.

In summer, we regularly pray for Candadian air which is our cool, dry friend. And, when we receive some we love you all.

In winter, you send us Alberta clippers and we send you a few choice words in return strongly suggesting you send your air elsewhere, thank you very much.




_________________________
Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton

Top
#146459 - 09/04/06 11:59 AM Re: What on earth is Ian up to now? [Re: Ajax]
RickF Offline
axiomite

Registered: 02/26/05
Posts: 5210
Loc: Vero Beach, Florida
>>>> In winter, you send us Alberta clippers and we send you a few choice words in return strongly suggesting you send your air elsewhere, thank you very much.

Jack, down here in our neck of the woods we praise the winter Alberta Clippers ... knocks the temps down into the low 70s / high 60s. Nice!
_________________________
Rick
Our Room

smile

Top
#146460 - 09/04/06 12:22 PM Re: What on earth is Ian up to now? [Re: Ajax]
real80sman Offline
connoisseur

Registered: 05/16/02
Posts: 1122
Loc: Ontario, Canada
Quote:

Cananda? Candadian?




LOL! I sat here just saying them over and over laughing!
_________________________
Shawn

Epic 80/600 + M3's + Custom Finish Algonquin V3's

Top
Page 3 of 4 < 1 2 3 4 >



Moderator:  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 

Home  |  Corporate Info  |  Products  |  Message Board  |  FAQs  |  Warranty  |  Site Map  |  Privacy Statement   |  Contact Us

©2014 Colquhoun Audio Laboratories Limited
All Rights Reserved.