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Audioman00
04-22-2004, 10:12 PM
Ok, I have a fairly high end system, but the speakers I am running just don't have that good of tweeters. I have a set of RadioShack add on's and they do actually aound quite good, but I wondered if anyone out there knows of a higher end add on tweet for this type of occasion? Thanks. audioman

92135011
04-22-2004, 10:38 PM
if its more upper range, then you can add on a super tweeter.
never used one or seen one for that matter but check this out

http://www.hifichoice.co.uk/review_read.asp?ID=2315

this baby goes up to 50khz no problem. Although...we cant hear that high so I'm not sure what its really used for.

WmAx
04-23-2004, 12:14 AM
Ok, I have a fairly high end system, but the speakers I am running just don't have that good of tweeters. I have a set of RadioShack add on's and they do actually aound quite good, but I wondered if anyone out there knows of a higher end add on tweet for this type of occasion? Thanks. audiomanHigher end? I guess the mere defintion of hi end is expensive? If so, then you can certainly fnd many more expensive units. Actually the Linaeum drivers possess some quite fascinating behaviors. The scope of which, not really relevant here. You can probably get better performance from that tweeter by doing three simple things.

(1) Remove the tightly spaced metal preforated and/or metal screen grill. It is causing problems. A poor choice for a grill on a high frequency driver, period.

(2) Remove the existing capacitor. Use a smaller value capacitor to raise the crossover frequency or at minimum replace the existing capacitor with similar value. I recommend a mylar or poly film capacitor. I believe that unit you have has an electrolytic 6.8uF?. They are not stabile; their value will drift(lower) significantly over time.

(3) Add an adjustable L-Pad control so that you can control the SPL level of this tweeter.

(4) Always use the tweeter so that it is more then 20 degrees angle, horiztonally, from the main listenig position(s). These things have a couple of peaks directly on axis, that quickly subsides off axis.

You can find the parts you need at www.partsexpress.com (http://www.partsexpress.com/) for realtively low cost.

-Chris

skeptic
04-23-2004, 03:20 AM
I've just added some tweeters myself to of all things, Bose 901. Of course in my situation, they required a separate amplifier so that they did not recieve the equalized signal. In your case, it won't.

Parts express has a fine selection at many price points. You can spend as little or as much as you want. You need to consider several things. First the impedence. Most are 8 ohms but some are 4. If you use an impedence which is different from the one you are using now, you will need to replace the crossover parts as well. This is just one capacitor and one inductor for a second order high pass filter (12 db per octave.) There is plenty of software to help you. If you get it wrong, you will have a poor match for the rest of the system and could even damage the new tweeter if the crossover frequency is too low for it. If you intend to use the old crossover parts, be sure that the new tweeter responds as low as the old one did. If you have a two way system, this can get pretty low. You also have to consider the sensitivity of the new tweeter. If there is a level mismatch, the new tweeter could make the speaker sound too bright or not bright enough. Choose a tweeter that is at leaast as sensitive as the manufacturer's original and use a 4 or 8 ohm L pad (depending on the impedence of the tweeter you buy) if necessary. Install it ahead of the crossover components. You could also try fixed resistors as well and Parts Express has a nice selection of them. Place them ahead of the crossover components instead of the L-pad as well. Mounting is another consideration. The tweeter should fit the hole in the cabinet left by the old tweeter. If it doesn't and you don't want to cut up the baffle board, leave the old tweeter physically in the box and build a small baffle board with some sort of support and sit it directly on top of the enclosure. Tweeters do not need a complete enclosure of their own.

You could also try an array of tweeters. I have found that using multiple tweeters where one fires forward and the others fire indirectly at the walls and ceiling makes a great improvement in sound.

hifitommy
04-24-2004, 08:30 AM
I have a set of RadioShack add ons and they do actually sound quite good, but I wondered if anyone out there knows of a higher end add on tweet for this type of occasion?
are these the linaeum tweets that ax infers? if so, they are ALREADY high end.

i agree about the grill, i never heard a speaker grill that i liked. i always listen with grills off.

raising the xover freq is another fine idea from ax. allowing the tweeter of function down into the midrange is just interfering with the midrange sound of the primary speaker. if i remember correctly, a 1uF cap will yield about a 5kHz rolloff point. i used a 0.5uF cap in my system for a rolloff point of 10k with dyna a25s. the speaker became nice and airy, something it hadnt been before.

and after listening to the new setup for about a week, invert the absolute phase of the tweet to see if that sounds better. it may or may not. in my case it did but that was just MY situation. and having the L-pad to adjust tweet level is important.

one more thing. place the tweet as near to the front edge of the speaker cabinet as possible which should align its apparent source with that of the other drivers and also reduce diffraction from the top of the cabinet a bit. also try setting it near the inside edge, center and outside edge to see how each of these positions affect the sound. if you hear differences, pick the one that sounds the most natural to you.