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Those speakers on Iowa DIY 2007 $300-$600 Class. So I would say they are very good. There are alot of other designs out there but if you are interested in them and build them then I doubt you will be dissappointed.
 

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Well, like most speakers (DIY and hi-fi commercial), the cabinets are woefully inadequate it seems, to prevent substantial acoustic output from the cabinet panels. This secondary acoustic output causes a underlying acoustic response to contaminate the response, resulting in distortion of the timbre. You could modify the build to radically improve this aspect, but it requires more work. The easiest method is to increase depth of the cabinet, and perhaps width(but do not add more than an inch or so to width, or you will start to effect the intended baffle step compensation built into the crossover). But mainly depth. Then you can add in a 2nd wall layer internally, and between the outer and inner walls, you will adhere Dynamat or comparable visco-elastic dampening material. This will create an extraordinarily efficient constrained layer system that will radically decrease the vibration/resonance in the panels. In addition to this, you need to increase the bracing radically. I would increase bracing to at least 3x, compared to the original bracing seen in the drawing. Braces should not be more than 3" from each other, and this goes for ever axis and wall. I recommend using oak for bracing and a high grade 13 ply void free birch plywood for the cabinet panels. MDF should only be used if budget won't allow for the other (superior) materials. If you build according to the above suggestion, the cabinet panels will have little to no audible acoustic output; a trait that is extremely rare in loudspeakers.

I do not know what acoustic fill/stuffing materials are suggested for this build. But you can usually improve on this also, as most DIYers(and most hifi makers) do not usually use the most efficient materials.

-Chris
 

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OR....... forget all the overbuilding of cabinets, all the money and time spent building such cabinets and gain a less colored sound by simply building an open baffle design. There are forums around the net that have plenty of info on what to look for in a driver if you decide to go that direction. Best thing i ever did to my system was to stop building boxes and go up in size of the drivers.......just my 2 cents worth, take it or leave it :bigsmile:

-andy
 

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Well, like most speakers (DIY and hi-fi commercial), the cabinets are woefully inadequate it seems, to prevent substantial acoustic output from the cabinet panels. This secondary acoustic output causes a underlying acoustic response to contaminate the response, resulting in distortion of the timbre. You could modify the build to radically improve this aspect, but it requires more work. The easiest method is to increase depth of the cabinet, and perhaps width(but do not add more than an inch or so to width, or you will start to effect the intended baffle step compensation built into the crossover). But mainly depth. Then you can add in a 2nd wall layer internally, and between the outer and inner walls, you will adhere Dynamat or comparable visco-elastic dampening material. This will create an extraordinarily efficient constrained layer system that will radically decrease the vibration/resonance in the panels. In addition to this, you need to increase the bracing radically. I would increase bracing to at least 3x, compared to the original bracing seen in the drawing. Braces should not be more than 3" from each other, and this goes for ever axis and wall. I recommend using oak for bracing and a high grade 13 ply void free birch plywood for the cabinet panels. MDF should only be used if budget won't allow for the other (superior) materials. If you build according to the above suggestion, the cabinet panels will have little to no audible acoustic output; a trait that is extremely rare in loudspeakers.

I do not know what acoustic fill/stuffing materials are suggested for this build. But you can usually improve on this also, as most DIYers(and most hifi makers) do not usually use the most efficient materials.

-Chris
I almost started laughing until I realized this couldn't be serious. 3" between braces?
 

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I wouldn't laugh; he's serious. 3" is a center-to-center distance in Chris' builds. Extreme but effective.
Frank
 

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OR....... forget all the overbuilding of cabinets, all the money and time spent building such cabinets and gain a less colored sound by simply building an open baffle design. There are forums around the net that have plenty of info on what to look for in a driver if you decide to go that direction. Best thing i ever did to my system was to stop building boxes and go up in size of the drivers.......just my 2 cents worth, take it or leave it :bigsmile:

-andy
There are certain things desirable to a close box; depending on one's objective(s). Simply changing to open baffle would not be appropriate in these cases. Also, much more attention needs to be put into open baffles also than is typically done by the overwhelming majority of DIYers. Linkwitz puts proper attention into it, and decouples the driver from the baffle in order to prevent the baffle from becoming a resonance source. You can also choose to build the baffle in such a way that it is simply not very resonant. Both methods are relatively rare among both commercial and DIY executions.

-Chris
 

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I almost started laughing until I realized this couldn't be serious. 3" between braces?
I am quite serious. This, combined with effective constrained layer construction to channel the energy into an efficient dampening layer trapped between two panels is a very effective, and not too difficult method of producing an extreme low coloration closed cabinet system. A very rare thing to find in both DIY and commercial systems.

-Chris
 

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I wouldn't use home store hardwood plywood for enclosures for fear of an unseen inclusion causing a buzz. If you have any woodworking lumber stores in Gilbert (and I don't mean Woodcrafters), they'll have furniture grade plywood, as well as the even better solid hardwood, veneer ply options (Baltic birch, Appleply, etc.) Remember, too, that if you plan to veneer the MDF, you should add the cost of the veneer to the MDF price when comparing to furniture-grade plywood options. It made my decision easy.
Frank
 

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I almost started laughing until I realized this couldn't be serious. 3" between braces?
There are two members who call for over-bracing and constrained-layer construction methods. Both individuals claim unbraced panels produce resonances which are measurable and audible.
I haven't seen testing that shows minimum bracing producing any audible and "NOTICEABLE" resonances.
I've personally built both over-braced and minimally braced enclosures and have not been able to discern an audible resonance from box panels. There MAY have been a measurable difference but I did no measurements.
In DIY projects, waste and non productive time and material are a goal but not an imperative. If a guy wants to add braces and make a constrained layer for his enclosure, so be it. Some theoretical bragging rights can be applied to either build philosophy however:
IE: mine is simpler and performs as good as I need it to (or)
mine is complex and EVERY possible construction method has been included for the last bit of
technical, electrical, audible, accuracy.
 

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Are these DIY tower enclosures well built or would you recommend changing the build?:

http://www.geocities.com/cc00541/MiniStatements_3.html

Click on cabinet drawings.
IMO the enclosures are well built and will work extremely well with the various drivers specified.
The drivers and crossover components are more responsible for the success of the speaker than the box. The box is a simply designed ported enclosure with more than adequate braces.
 
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