Home » Audio » Speaker » Digging out the old (?) ART array - some questions
icon5.gif  Digging out the old (?) ART array - some questions [message #81693] Mon, 30 November 2015 11:04 Go to next message
Rolf is currently offline  Rolf
Messages: 3
Registered: November 2015
Location: Kenya
Esquire
Dear all,

greetings to all of you from Kenya.

I just registered to find out more about the 2009 ART array speaker.

...the ones explained in detail here:
http://audioroundtable.com/GroupBuild/Projects/

...and with nice photos here: https://fredt300b.smugmug.com/Hobbies/The-ART-Arrays/i-Hhp7hL9


I actually think I read quite a bit about it, including the long debate at http://techtalk.parts-express.com/showthread.php?209376-ART-com-line-array

AND, most importantly, I already bought the 16 Dayton DC130BS-8 Laughing

Rather than building/using passive crossovers, I am planning to use - for the time being - an active solution. I own a nanoAVR-HD from miniDSP, which should do the trick.

Before starting to build the speakers, I would however like to clarify a few issues, hoping that some of you were involved in the making and still remember these details - maybe Scott Placke is still around?

First of all, the arrangement of the woofers on the baffle. I assume they were deliberately moved slightly to one side, to minimize baffle-step issues. But were these really serious?
If not, then I would prefer centering the speakers vertically.

Secondly, the dimensions of the port tubes: these ought to be 4'' diameter and 4-3/8" length resulting in a 49 Hz tuning frequency. Typing these dimensions and the enclosure volume (~14.5 liters per woofer) into a standard tuning frequency calculator (I am using the German program Boxsim), results in a much higher tuning frequency, namely something around 70 Hz.
Anything that I am overlooking here?

I would appreciate very much hearing back from you.

Best regards,
Rolf

Re: Digging out the old (?) ART array - some questions [message #81708 is a reply to message #81693] Wed, 02 December 2015 09:48 Go to previous messageGo to next message
Rolf is currently offline  Rolf
Messages: 3
Registered: November 2015
Location: Kenya
Esquire
Nobody with any idea? Confused
Re: Digging out the old (?) ART array - some questions [message #81711 is a reply to message #81708] Wed, 02 December 2015 15:31 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 17591
Registered: January 2001
Illuminati (33rd Degree)

I didn't mean to ignore you but I've already given my input on this matter. Not sure anyone else has any other thoughts, but if so, I'm sure they'll chime in.

In my opinion, it's a great speaker, built as Fred designed.

Re: Digging out the old (?) ART array - some questions [message #81712 is a reply to message #81711] Thu, 03 December 2015 10:06 Go to previous message
Rolf is currently offline  Rolf
Messages: 3
Registered: November 2015
Location: Kenya
Esquire
Thank you, Wayne.

I will do.

In the meantime I have figured out my mistake when calculating the resonance frequency of the port tube.
One needs to use the entire chamber volume (not dividing this by four, as I earlier did) and the equivalent volume (Vas) equal four times the single Vas.
Then the calculation matches that published by the builders of this speaker.

Once ready, I will post some photos.

Best regards,
Rolf
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