Shock-Late Posted October 17, 2004 Share Posted October 17, 2004 hi folks, since two years now (geeez, amazing how time flies!) I've been considering buying ALK type A networks for my old, type AA laScalas. being young and poor (well, let's say "student"), this hasn't been done yet for budget reasons. Meanwhile i've been updating the midrange horns (EV SM120A in place of the K400), and three months ago i replaced the K77M tweeters with beyma CP25. That last change, while improving the QUALITY of treble, also made my speakers sound WAY too bright, almost unbearable, when it was just balanced with the K77M. My listening room is quite small and very "bright" sounding, so any excess of high frequencies is disastrous. Also, i listen mainly to Cd's, through a SS amp. So after asking Al for a solution, i dropped the tweeter network level down by 3db by connecting it to a lower transformer tap, wich was easy to do on the AA and worked great. My main concern is: if I buy ALK networks, wich is still on my wishlist, will i be able to modify it so that the tweeter doesn't sound too hot? there's no way I can try a pair before ordering as -as some of you may already know- I live in Brussels, Belgium and nobody owns ALKs around here. thanks for any advice or comment... Frans Quote Link to comment Share on other sites More sharing options...
sunnysal Posted October 17, 2004 Share Posted October 17, 2004 Hi Frans, I am sure that Al would be glad to drop the tweeter level on your pair of ALKs by 3db (or whatever amount you decide is correct), he builds them one by one and I sure he will make a small mod like that for you without any additional charge, regards, tony Quote Link to comment Share on other sites More sharing options...
Daddy Dee Posted October 17, 2004 Share Posted October 17, 2004 You've probably noticed from Al's pics of the network that he builds it so the user can easily change taps on the autoformer to adjust the level of the midhorn. I would think that Al would be able to offer similar user flexibility for the tweeter. Quote Link to comment Share on other sites More sharing options...
Deang Posted October 17, 2004 Share Posted October 17, 2004 "That last change, while improving the QUALITY of treble, also made my speakers sound WAY too bright, almost unbearable..." So much for "quality". Quote Link to comment Share on other sites More sharing options...
Shock-Late Posted October 17, 2004 Author Share Posted October 17, 2004 Well, yes, if the tweeter is a better tweeter but is too loud, it can't sound good. What's so strange in what I wrote? Quote Link to comment Share on other sites More sharing options...
sunnysal Posted October 17, 2004 Share Posted October 17, 2004 dean is what we call a "stocker"...lol, tony Quote Link to comment Share on other sites More sharing options...
Deang Posted October 17, 2004 Share Posted October 17, 2004 Not really Tony, I just think there is more to doing the mods correctly than throwing horns and drivers together. Networks are optimized to work with specific drivers, and I guess my thinking is that the main thing that determines whether a driver is "quality" or not -- is if it integrates properly with the rest of the speaker. What good is a high quality driver if just ruins the balance and musicality of the speaker? Shock-late, my apologies, I didn't mean to come off like that. Quote Link to comment Share on other sites More sharing options...
Shock-Late Posted October 18, 2004 Author Share Posted October 18, 2004 No problem Dean...lol and you're perfectly right. BUT the mod i did to balance the beyma to the rest was easy to do and effective, and my scalas really sound a lot better now than with the stock tweeter... Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 18, 2004 Share Posted October 18, 2004 I'm running JBL baby-butts on ALK's with no attenuation on SS gear, to boot! This would be a very close approximation to what you are running. Believe it or not, the connecting WIRE between the tweets and the crossover can be changed to alter the freq response. Dramatic effect. Try this before you do anything else! Combined with the appropriate room treatment placement, I found that I can leave them "straight". The baby-butts have a very wide dispersion, wider than the stock ones for sure. This means that the "new" reflections from the new dispersion pattern caused the room treatments to be rearranged when I made the change. DM Quote Link to comment Share on other sites More sharing options...
Shock-Late Posted October 18, 2004 Author Share Posted October 18, 2004 ---------------- On 10/18/2004 11:21:40 AM D-MAN wrote: Believe it or not, the connecting WIRE between the tweets and the crossover can be changed to alter the freq response. DM ---------------- Well, i actually have QEd Anniversary silver (mixed with copper) wire between tweeters and crossovers, and QEd regular copper wire on the other drivers. I'm sure it has to play a part in the relative loudness of the tweeters, but enough for needing a 3dB attenuation? I'm quite sceptical... Quote Link to comment Share on other sites More sharing options...
dubai2000 Posted October 18, 2004 Share Posted October 18, 2004 Frans, well, like D-Man I am using those JBL tweeters with Al's 'A' crossover and I don't find the new tweeter too bright. Considering that Al himself uses the Beyma, I was wondering if it's really new new tweeter that causes such brightness. My initial though was that perhaps a tube amp might be more fitting for such a combo....but of course I AM biased towards tubes . I am not technically informed enough, but aging parts in your networks cannot be the reason for what you are experiencing? Just some thoughts.....which, I admit, won't help to improve the situation right now. And before I forget: I am very happy with my ALKs and don't think you'd regret purchase . Wolfram Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 18, 2004 Share Posted October 18, 2004 Frans, -3db's would be half as loud, are you sure that you need to attenuate that much? More like maybe 1db or so I would guess... I would not recommend that you need to change gear from SS to tubes, etc., unless you feel that its response is causing a portion of the problem. Good tube gear will also produce highs at the same volume, etc... As for wire, well, no need to "step down" from what you've got, so we'll drop that suggestion. Sounds like a resistor L-pad circuit would be your next bet. John Warren has the L-pad design that would meet your needs, check out his website: http://home.comcast.net/~wooferboy/Page_6.html Al K, or Dean could also give you some ideas, too. DM Quote Link to comment Share on other sites More sharing options...
scriven Posted October 18, 2004 Share Posted October 18, 2004 -3db is half the power not half as loud. -10db is usually considered half as loud. Quote Link to comment Share on other sites More sharing options...
3dzapper Posted October 18, 2004 Share Posted October 18, 2004 A simple -3Db@8ohms L-pot in the HF line will serve well with the ALK type A's. This is what I intend to do with my JBL 2404s. Center position will be -1.5Db which, I feel, will be just right, but will allow an additional -1.5Db for lousy CDs and full output for weak treble sources. YMMV Rick Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 19, 2004 Share Posted October 19, 2004 ---------------- On 10/18/2004 4:15:04 PM scriven wrote: -3db is half the power not half as loud. -10db is usually considered half as loud. ---------------- Scriven, negative on that, good buddy! -3db is a SPL level, not a wattage rating. It's -10x the power, 1/2 the loudness from the reference (0db). DM Quote Link to comment Share on other sites More sharing options...
sunnysal Posted October 19, 2004 Share Posted October 19, 2004 rick, so you find the 2404H too hot with the ALK crossover? regards, tony Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 19, 2004 Share Posted October 19, 2004 Shock, If you look at my web site you'll see that I have incorporated a switchable L pad in the tweeter on my ES5800 network. This switchable pad is probably what you need to calm your tweeter. It can be added to the tweeter on virtually any network, including my designs. If your interested I can post the schematic of the switch wiring and the resistor values. It's no big secret! An adjustable L pad will work too, but I don't like them becasue they are not reliable. Their attenuation is unpredictable. Their "resetability" is poor and they don't stay where you set them. The switch selects precicisely 0, 2, 4, 6, and 8 dB. Al K. Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 19, 2004 Share Posted October 19, 2004 Speaking of L-pads, I found that the "adjustable" ones actually sounded bad on my speakers. What's up with that? I assume that fixed, high-quality resistors would sound better? What's the skinny on these things? DM Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted October 19, 2004 Share Posted October 19, 2004 Dman, "L" pads are simply the cheap substitute for the autotransformer. I would not use them on the squawker, maybe that is where you had it connected. I think you can get away with it on the tweeter though. Al K. Quote Link to comment Share on other sites More sharing options...
D-MAN Posted October 19, 2004 Share Posted October 19, 2004 Al, you are indeed correct, I did have them on the mid-range as an alternative to the autoformer, exactly as you suspected. DM Quote Link to comment Share on other sites More sharing options...
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