albertli Posted June 21, 2017 Author Share Posted June 21, 2017 I'm waiting for those interconnects between EQ and the active crossover to come, and I could make some noise after. Am really excited to see what would be the result. Please do advise for the following: 1). I read on one post that I have to protect the CD with a cap in series after the amp. My 2A3 will be the amp in that position. How big the cap I would need for this purpose? The 2A3 could only play 3.5w max. 2). I only have to lightly stuff the upper portion of the box. Is it correct? 3). Heard that the polarity of the CD should be reversed, Red to diaphragm (-) and Black to (+). Is it the case? Thanks Quote Link to comment Share on other sites More sharing options...
albertli Posted June 30, 2017 Author Share Posted June 30, 2017 I have this baby starts singing for me at last. They play all sort of music beyond my expectation and what can I ask for more.... To my astonishment these 2445J sound so smooth and lush and even the highest notes on violin didn't sound harsh. I run them 2 ways at the moment at 700hz. The bass is maturing and hope they give more low end after 100 hours. My friend will do the measurement for me this week end, see what they sound after EQ. 1 Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted June 30, 2017 Share Posted June 30, 2017 Have you added the crossover and EQ yet. If you have not then the highs are being attenuated a fair amount (the EV HP640 is a CD horn and will need the obligatory high-end boost. Where have you crossed (500 or 600Hz I assume). Also if you are using DSP (and I hope you are), have you done the time alignment yet?. That combo (JBL and EV) should sound quite good. Quote Link to comment Share on other sites More sharing options...
albertli Posted July 1, 2017 Author Share Posted July 1, 2017 7 hours ago, PrestonTom said: Have you added the crossover and EQ yet. If you have not then the highs are being attenuated a fair amount (the EV HP640 is a CD horn and will need the obligatory high-end boost. Where have you crossed (500 or 600Hz I assume). Also if you are using DSP (and I hope you are), have you done the time alignment yet?. That combo (JBL and EV) should sound quite good. Tom, I cross them at 700hz with the cx3400 in two way. My friend will tune them with my eq tomorrow. I'm new in speakers and don't know much above time alignment. Is it to delay the bass in ms kind of thing. There is a attenuator in my cx3400. Will report after the adjustments. Albert Quote Link to comment Share on other sites More sharing options...
Marvel Posted July 1, 2017 Share Posted July 1, 2017 You would normally have to delay the mid and tweeter, to match the length of the bass horn. The 4" dia. Ports at 7 1/2" should be about right. The padding in the doghouse shouldn't be needed if you ported it. I believe the padding is for a sealed/standard doghouse. Quote Link to comment Share on other sites More sharing options...
albertli Posted July 2, 2017 Author Share Posted July 2, 2017 13 hours ago, Marvel said: You would normally have to delay the mid and tweeter, to match the length of the bass horn. The 4" dia. Ports at 7 1/2" should be about right. The padding in the doghouse shouldn't be needed if you ported it. I believe the padding is for a sealed/standard doghouse. I didn't pad the dog house but with a thin layer of pad in the add-on bass bin section. For the delay on mid and high, I doubt if I can do it with the Behringer cx3400. Quote Link to comment Share on other sites More sharing options...
albertli Posted July 2, 2017 Author Share Posted July 2, 2017 My friend did the measurement for me today. The result is attached. Please do comment if you find anything. I didn't try the mod that Dennis suggested yet and I thought I'd try it very soon. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 2, 2017 Share Posted July 2, 2017 That looks fairly good. Could you tell us about how the measures were done (indoors or outside, amount of averaging etc)? Quote Link to comment Share on other sites More sharing options...
albertli Posted July 2, 2017 Author Share Posted July 2, 2017 Tom, It was done at my listening room and the mic was set right at my listening position, about 15 feet away from both speakers. He used 1/12 smoothing with pink noise. The graph showed the result of the left speaker, the right one looked almost the same. It showed a bit rough from 100-1000, but the EQ couldn't make it better than this. I thought I have to try Dennis's suggestion to line the doghouse with foam. Albert Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 2, 2017 Share Posted July 2, 2017 For an indoor measure without too much smoothing, that looks gosh darn good. Since that HP 640 horn is fairly narrow in its dispersion, you have minimized a number of the room interactions. My guess is that the imaging is fairly convincing and dramatic? What is your subjective impression? Job well done! Quote Link to comment Share on other sites More sharing options...
albertli Posted July 3, 2017 Author Share Posted July 3, 2017 6 hours ago, PrestonTom said: For an indoor measure without too much smoothing, that looks gosh darn good. Since that HP 640 horn is fairly narrow in its dispersion, you have minimized a number of the room interactions. My guess is that the imaging is fairly convincing and dramatic? What is your subjective impression? Job well done! Tom, To be honest, I don't really know much about speaker building and theories etc. I did finished couple speakers and big thanks to all knowledgeable, open minded forum members who contributed comments and ideas. I only have two days experience with this horn and I believe they would stay in my listening room for a long period of time. They sound so smooth and lush of which is really out of my imagination. The highest notes of trumpet and violin are so admirable. Piano is so grant and the vibrant on every key is lively present. The voices of all soprano I like are so smooth and gorgeous. Only the bass and mid bass are a bit too soft and weak if compare to the my last one. I'd go for the mod to line the doghouse for sure. Will report. Albert Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted July 3, 2017 Share Posted July 3, 2017 I don't think lining the doghouse is going to boost a "soft and weak bass". The system is a candidate for a subwoofer to help the bass. Most La Scala systems are this way also. Keep up the good work Quote Link to comment Share on other sites More sharing options...
absolve2525 Posted July 4, 2017 Share Posted July 4, 2017 I have a pair of those exact horns. Great sound! Looking good ☺️ Quote Link to comment Share on other sites More sharing options...
albertli Posted July 6, 2017 Author Share Posted July 6, 2017 I have the doghouse lined with foam as of Dennis recommended. The result is amazing with the measurement below. The bass is deep and solid and I don't think I'll need a sub-woofer. There is still a big dip at 55hz, this might be a room mod but can't correct it with my EQ. Any ideas? Quote Link to comment Share on other sites More sharing options...
albertli Posted July 15, 2017 Author Share Posted July 15, 2017 I have found couple Ciare tweeters sitting doing nothing. Will try them on with 3 ways at 600/6000. Any recommentations? Quote Link to comment Share on other sites More sharing options...
albertli Posted August 16, 2017 Author Share Posted August 16, 2017 Hi guys, Lately my friend offered me a pair of genuine 8 ohm diaphragm and they both measured 5.8/5.9 ohm. Since my drivers are 16 ohm 2445J type. Is there any ill effect for me to put these diaphragms into my drivers? I mean do they sound bad and or would sound better because they are genuine? Thanks Albert Quote Link to comment Share on other sites More sharing options...
albertli Posted August 21, 2017 Author Share Posted August 21, 2017 On 8/16/2017 at 8:25 AM, albertli said: Hi guys, Lately my friend offered me a pair of genuine 8 ohm diaphragm and they both measured 5.8/5.9 ohm. Since my drivers are 16 ohm 2445J type. Is there any ill effect for me to put these diaphragms into my drivers? I mean do they sound bad and or would sound better because they are genuine? Thanks Albert I tried the said drivers on last night and found they sounded more vivid and detail but with a kind of annoying Zzzzzz. I thought it is the result of the efficiency. Quote Link to comment Share on other sites More sharing options...
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