Deang Posted September 30, 2013 Author Share Posted September 30, 2013 From Al, Dean,... the microphone used for the tone burst tests was a Bruel & Kjaer 4133 1/2 inch capsule on a 2639 preamp. The response tests used a 4135 1/4 inch capsule with a Larson Davis adaptor. These are the industry standards.Al k. Quote Link to comment Share on other sites More sharing options...
Schu Posted October 1, 2013 Share Posted October 1, 2013 starting to get excited over here! Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted October 1, 2013 Share Posted October 1, 2013 Hopefully it won't fit anything I own. I'm semi content with what I have and have a weakness for upgrades. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted October 1, 2013 Share Posted October 1, 2013 (edited) I was confused since I thought this thread was about the horn that was fabricated. However, I wanted to make sure that everyone understands that while the ringing and burst tests are interesting, they mostly tell us about the driver (the diaphragm material and the strength of the motor). They do not tell us much about the horn itself. The freqeuncy response, on- and off- axis, would be informative (although not the complete story). Edited October 31, 2013 by PrestonTom Quote Link to comment Share on other sites More sharing options...
Arkytype Posted October 1, 2013 Share Posted October 1, 2013 Tom, et al, A complete set of acoustic testing for the horn/driver combination is in the works. Lee Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 2, 2013 Share Posted October 2, 2013 Nice, I am anxious to see the results. Thanks Lee Dave Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 2, 2013 Share Posted October 2, 2013 I didn't realize there was such a big difference between these two, yikes. Neodymium is cool (or is it Neo is cool, however this driver was chosen for its size not it's magnet composition. Actually my search criteria was size, diaphragm material, and response. The size was a major limitation, I only found a few drivers that could meet my criteria ,those were offerings from B&C and Celestion. I chose the B&C because I prefer the sound of Mylar diaphragms to Aluminum or Titanium. The B&C DE-38 has a very smooth response in the audible, and extended range. I did not expect it to extend to 30khz Dave Quote Link to comment Share on other sites More sharing options...
Deang Posted October 2, 2013 Author Share Posted October 2, 2013 I was confused since I thought this thread was about the horn that was fabricated. However, I wanted to make sue that everyone understands that while the ringing and burst tests are interesting, they mostly tell us about the driver (the diaphragm material and the strength of the motor). They do not tell us much about the horn itself. The frequency response, on- and off- axis, would be informative (although not the complete story). Hi Tom, Tone burst tests on the drivers were performed with horns attached. The horn for the B&C DE38 is not the same as the horn being sold by the eBay seller. On and off-axis frequency response plots for this combination are on the first page. While there have been more than several different tweeters available for use as replacements to the K-77, there has only been one that could be used as a direct replacement that could be mounted above the mid-horn within the top section -- the B&K Sound CT-125, which uses the Eminence APT 50. I guess we now have to differentiate between those made in Poland (original Eminence APT-50 and the past/current CT-125). For clarification puposes, the driver used by Al was the original Eminence APT-50. The APT-50 is a $25.00 tweeter. The B&C DE38 is a $100.00 tweeter. While it's not always true that you get what you pay for, I do think it's mostly true. Quote Link to comment Share on other sites More sharing options...
John Warren Posted October 5, 2013 Share Posted October 5, 2013 It's comparative testing. As long as the same microphone is used, the testing is valid, yes? Sure, it's a single frequency, but if it rings like a telephone at 6kHz, what hope is there for it throughout the rest of its useable range? ...on-axis frequency response (roughness or degree of "ripple") and bandwidth correlate to transient behavior, they're orthogonal views of the same thing. In other words, can't have one without the other. So tone burst measurements, ala Gilbert Briggs, don't say very much. That said, I've measured B&C units, they're decent. Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 7, 2013 Share Posted October 7, 2013 That said, I've measured B&C units, they're decent. Excellent, that's good news. I have had good results with B&C drivers as well. Dave Quote Link to comment Share on other sites More sharing options...
babadono Posted October 23, 2013 Share Posted October 23, 2013 Hi Dave et al, Well it is good to have the forum up and running again. Any thing new on these babies after the 2 week hiatus? Eric Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 24, 2013 Share Posted October 24, 2013 Yes, got some tests results back on the tweeter. The directivity plot looks good. Dave Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 24, 2013 Share Posted October 24, 2013 (edited) Vertical polars Obviously designed for horizontal orientation. Edited October 24, 2013 by GotHover Quote Link to comment Share on other sites More sharing options...
djk Posted October 25, 2013 Share Posted October 25, 2013 That looks great! Quote Link to comment Share on other sites More sharing options...
NBPK402 Posted October 25, 2013 Share Posted October 25, 2013 There was (is) a guy selling those wooden horns on Ebay that looked similar to these. Are they similar? http://www.ebay.com/itm/Wood-Wave-Guide-Horn-Tweeter-Driver-Home-Audio-Klipsch-K-77-replacements-/141053062214?pt=US_Pro_Audio_Speaker_Drivers_Horns&hash=item20d76aec46 Tame the your Klipschorn, La Scala or Belle with our new direct replacement wood waveguides! Every horn is precisely cut with a CNC and completely hand finished then assembled right here in Maine. Waveguide horns are used in most studio monitors and noted for they’re linear response, openness and lack of high frequency beaming. The waveguide gives you all the sound quality of a horn without the flaws and coloration. We use the American made eminence apt-50 and can make these horns out of any wood (some woods may add extra cost). Our goal is to use mostly upcycled wood to reduce shop waste and save the extra cutting of trees, also reducing the cost to you!! What to expect.. The k-77 is a great tweeter but has always been a little hot in my opinion, almost a little harsh and over bearing. I love how these waveguides smooth the high end without losing presences. Also there is a better balance between the mid range and high frequency with less separation between drivers. I would be very unhappy if I bought a tweeter from someone online and find out it was not what I was looking for. If you are unhappy with your order you can return for a full refund within 7 days of receiving it. So, the risk is mine, just send it back in perfect condition I’ll refund your money! Shipping is not refunded. Thank you for taking the time to view are horns! That is for a pair including the drivers? SAeems like a good deal. Quote Link to comment Share on other sites More sharing options...
mark1101 Posted October 25, 2013 Share Posted October 25, 2013 (edited) Dave, This is great work, and it is a beautiful piece. But, can I ask why eliptical? To match the eliptrac? Was it not possible or purposely unintended to do a pure tractrix to match the other Fastracs? I guess I'm asking if you intend to do a tractrix version so an audiophile can pick a set of elipticals, or a set of "old school" tractrix? I'm thinking that with you and that machine........it's only time that's in the way. Edited October 25, 2013 by mark1101 Quote Link to comment Share on other sites More sharing options...
NBPK402 Posted October 25, 2013 Share Posted October 25, 2013 Very nice thank you for the info next question I guess is to Dave when will they be ready. There is still a bit of work to be done on these. I hope to have a batch ready soon, however I have orders to fill and little time. Dave How much are these going to be? Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 26, 2013 Share Posted October 26, 2013 How much are these going to be? I apologize, but this is not the place. Dave Quote Link to comment Share on other sites More sharing options...
Guest David H Posted October 26, 2013 Share Posted October 26, 2013 Dave, This is great work, and it is a beautiful piece. But, can I ask why eliptical? To match the eliptrac? Was it not possible or purposely unintended to do a pure tractrix to match the other Fastracs? I guess I'm asking if you intend to do a tractrix version so an audiophile can pick a set of elipticals, or a set of "old school" tractrix? I'm thinking that with you and that machine........it's only time that's in the way. The transition from square to round is tricky, and less forgiving than the Elliptical. I have however considered what you are suggesting. I suppose once I get familiar with 3D CNC the project will be fairly straight forward. Anyone here familiar with Solidworks? Dave Quote Link to comment Share on other sites More sharing options...
NBPK402 Posted October 26, 2013 Share Posted October 26, 2013 How much are these going to be? I apologize, but this is not the place. Dave Sorry, PM sent Quote Link to comment Share on other sites More sharing options...
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