Q. Besides the normal features I need something very user-friendly on top of being able to run statistics by user (to track number of recurring issues for continued training etc). Free would be nice, but not necessary. Would want to self-host.
A. Try Request Tracker - http://bestpractical.com/rt/
It's free and is basically a MySQL back end and php front end.
It's free and is basically a MySQL back end and php front end.
Why do you make a hole in a subwoofer/woofer cabinet?
Q. I want to build a pair of speakers with a woofer or subwoofer sitting UNDER my desk and two small bookshelf speakers sitting ON my desk with a mid-range and tweeter in each of them. Will this work? And also, why do you make a hole in the cabinet of the subwoofer/woofer? Should I do this? If so, how?
A. No you probably shouldn't do that. Mathematics to design a sealed box system can be done using simple arithmetic but to design a ported system requires 4th order differential equations. You can do it because these days software does all the hard parts for you. http://www.ht-audio.com/pages/BassBoxPro.html but for a simple system like that you're probably better off going with a sealed system. But just FYI, the "hole" or port is tuned to a specific frequency. At that tuned frequency the port and the woofer are in phase thus adding increasing output. Below this frequency they move out of phase and cancel causing the roll off to be steeper. Above the port frequency the port gradually produces less and less output until eventually it in effect ceases to exist.
You may want to consider a kit from Parts Express. http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=769 I'm not sure if any of these will work for you.
You can develop your own design but passive crossover design (or active for that matter) is not a trivial task. Proper measurement equipment and CAD software can make it pretty easy after you've had some experience. First you need Arta http://www.fesb.hr/~mateljan/arta/ which you can download and use free. You will also need a measurement microphone and a good sound card. http://www.earthworksaudio.com/our-microphones/m-series/m30/ Once you have made measurements you need the crossover design software http://www.ijdata.com/ (800 Euro or about US$1050). Without these tools it's pretty hard to get good results.
Speaker building is a fun hobby and I don't want to discourage you from it. Especially in the mass market speaker manufacturers don't set the bar very high so even if you don't know what you're doing it's not too difficult to beat the performance of commercial options simply because you usually don't have access to the ultra cheap OEM drivers. You simply can't buy crappy enough drivers to sound as bad as most mass market commercial options!
Visit the AVS Forum DIY section, http://www.avsforum.com/avs-vb/forumdisplay.php?f=155 and take a look at some of the projects on the Parts Express web site. Sometimes PE does have "Buyout" deals giving you access to the really cheap drivers like mass market products use. This will allow you to give speaker building a try without spending much money.
Another option would be to look at "full range" drivers. This would eliminate the need for passive crossovers. The subwoofer is pretty simple and hard to screw up. Find a woofer with a low Fs (Resonance Frequency) and a medium Qts (damping factor) Qts = 0.7 needs to be infinite baffle, greater than 0.7 possibly can be used in open baffle with EQ but don't put it in any box of any size. Making the sealed box too large is far better than making it too small so error on the large side and you will be ok. Tang Band makes some really nice high excursion small woofers around 6.5" that would work great.
Have fun!
mk
You may want to consider a kit from Parts Express. http://www.parts-express.com/wizards/searchResults.cfm?srchExt=CAT&srchCat=769 I'm not sure if any of these will work for you.
You can develop your own design but passive crossover design (or active for that matter) is not a trivial task. Proper measurement equipment and CAD software can make it pretty easy after you've had some experience. First you need Arta http://www.fesb.hr/~mateljan/arta/ which you can download and use free. You will also need a measurement microphone and a good sound card. http://www.earthworksaudio.com/our-microphones/m-series/m30/ Once you have made measurements you need the crossover design software http://www.ijdata.com/ (800 Euro or about US$1050). Without these tools it's pretty hard to get good results.
Speaker building is a fun hobby and I don't want to discourage you from it. Especially in the mass market speaker manufacturers don't set the bar very high so even if you don't know what you're doing it's not too difficult to beat the performance of commercial options simply because you usually don't have access to the ultra cheap OEM drivers. You simply can't buy crappy enough drivers to sound as bad as most mass market commercial options!
Visit the AVS Forum DIY section, http://www.avsforum.com/avs-vb/forumdisplay.php?f=155 and take a look at some of the projects on the Parts Express web site. Sometimes PE does have "Buyout" deals giving you access to the really cheap drivers like mass market products use. This will allow you to give speaker building a try without spending much money.
Another option would be to look at "full range" drivers. This would eliminate the need for passive crossovers. The subwoofer is pretty simple and hard to screw up. Find a woofer with a low Fs (Resonance Frequency) and a medium Qts (damping factor) Qts = 0.7 needs to be infinite baffle, greater than 0.7 possibly can be used in open baffle with EQ but don't put it in any box of any size. Making the sealed box too large is far better than making it too small so error on the large side and you will be ok. Tang Band makes some really nice high excursion small woofers around 6.5" that would work great.
Have fun!
mk
what is a good help desk tracking system?
Q. My company and I are looking for a reliable help desk tracking software. We wanted to be webbased, easy to use for end users, asset management, able to assign tickets and to have a report builder.
Thanks!!
Thanks!!
A. Hi,
I'm also looking for the same sort of help desk tracking system which is free and open source. So far, I found this site to be the best. http://www.helpdeskreloaded.com/
Their demo system can be accessed from http://www.demohelpdesk.com/index.php
Check it out. Hope it helps.
For more enterprise software listing, check out http://www.wareprise.com
I'm also looking for the same sort of help desk tracking system which is free and open source. So far, I found this site to be the best. http://www.helpdeskreloaded.com/
Their demo system can be accessed from http://www.demohelpdesk.com/index.php
Check it out. Hope it helps.
For more enterprise software listing, check out http://www.wareprise.com
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