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Old

Radio Shack Linaeum measurements

Posted 14th March 2014 at 11:40 PM by hbc

I bought a pair of these in about '95 and modified them a bit. I blocked up the ports, stuffed them with fluff, replaced the inductor with an air cored type, and rewired with CAT5. I also removed the top cages and grills which subsequently got lost, and also removed the rubber from the woofer voice coil, and put in a phase plug fashioned from some dowel.

I lived happily with these for about 10 years, ending up with an 18" subwoofer which used an equalised bass guitar speaker. The advantage of this equalisation was a degree of cancellation between the sub and the little woofers, resulting in a very smooth lump free transition in the listening position.

I found them to be an excellent tool in the development of audio stuff, it was quite easy to discern the difference between different types of cables, for me and friends, etc etc.

I bought another pair but I was wondering if the tweeters were fried as they sounded a bit dull compared to my modded...
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hbc
diyAudio Member
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Old

Goodmans Magnum SL woofer distortion

Posted 5th March 2014 at 04:17 PM by hbc

I have a pair of tired Goodmans Magnum SLs. They are in reasonable condition, but one mid is blown, and they have no front covers. I tried grafting a new mid on to the broken one, expecting I would need to do some crossover work, but it really did not sound good. A very unpleasant sound that I found quite fatiguing and unpleasant to listen to coming from the upper bass lower mid area, quite a relief to turn it off actually. I put bigger and bigger choke on the woofer to try and filter it away, but that didn't work. I took of the dust cap in case that was causing it but no.


I am thinking of re-purposing the boxes now, but first did just check the woofer to make sure it has a problem. Below are some distortion plots, for a good one, the bad one and also for a Wharfedale Dovedale 3 woofer, with fixed rubber (Note the different scale). These plots were done at quite low level, like normal neighbour friendly listening levels.
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hbc
diyAudio Member
Posted in Uncategorized
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