kg4guy Posted March 30, 2008 Share Posted March 30, 2008 Would adding inductors on the tweeter and squawker make a improvement in the type E crossover and if so what size inductors should be used? Quote Link to comment Share on other sites More sharing options...
Guest " " Posted March 30, 2008 Share Posted March 30, 2008 How about convert to e-2? It may require parts you currently do not have. Quote Link to comment Share on other sites More sharing options...
BEC Posted March 30, 2008 Share Posted March 30, 2008 Fritz, You posted the Heresy II crossover, not the E-2. Here is the E-2. Bob Crites Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted March 30, 2008 Share Posted March 30, 2008 But what's the answer to kg4guy's question? Erik Quote Link to comment Share on other sites More sharing options...
kg4guy Posted March 30, 2008 Author Share Posted March 30, 2008 Thanks-I just built some Cornscala type speakers and I am playing with the crossovers I am using a type E with a 8 ohm 15 " woofer and a K-55 and a APT tweeter.Sounds good but the bass is a little weak and the mid and highs nice but could be better. Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted March 30, 2008 Share Posted March 30, 2008 If he wanted to install the inductors, how would he do it? There really wasn't an explanation given for the crossover he has. Erik edit: And what would the values of the inductors be? ....hopefully you'll get some help. Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 1, 2008 Share Posted April 1, 2008 Someone unknowingly gave you a nudge in the right direction, but a little more work is needed. Wish I could help. bump! Quote Link to comment Share on other sites More sharing options...
kg4guy Posted April 1, 2008 Author Share Posted April 1, 2008 Thanks for the support I switched it over to a type B with Kimber Kaps and Dayton Film and Foil bypass caps.The Type E 's tweeter and sqawker have there phase reversed so I was stuck but Bob sent me a type B shematic however I think I need a 4 ohm 15 as the 8 ohm is a little weak but they sound awesome anyway the way they are.Anyone know the Eminence part # on that 4 ohm 15" woofer? Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 1, 2008 Share Posted April 1, 2008 Good job on figuring out how to wire those on your own. If you like, you can also find solder terminal lugs, or lugs that have eyelets (sometimes used for solder connections on barrier strips) that can be mounted to the board so that the leads from caps and so forth can have a more secure place to connect. Sometimes it's necessary to pad more efficient tweeters and midranges so that their output matches more suitably to that of the woofer. Erik Quote Link to comment Share on other sites More sharing options...
kg4guy Posted April 1, 2008 Author Share Posted April 1, 2008 I was thinking about that but if I can get a more efficient woofer to match the high end I may do that because the top end is sounding very nice I do want to touch it.Thanks Eric Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 1, 2008 Share Posted April 1, 2008 Sure. The setup you've created looks really interesting, by the way. I totally understand about not wanting to mess around with something more once it sounds right. The top end is really the critical part, and hopefully you'll find the best way to balance everything out. Nice work -- I've always thought the form-follows-function, sort of utilitarian-tech of uncovered (sans grille) drivers in simple boxes or unfinished MDF to be visually appealing. Nice veneer can be good too, but I think it's just sort of interesting sometimes to consider performance only. I've heard great sounding amplifiers installed in aluminum baking pans. Erik Quote Link to comment Share on other sites More sharing options...
kg4guy Posted April 1, 2008 Author Share Posted April 1, 2008 The wood is 3/4 birch with poly finish I got a bunch of this birch from a freind who owns a Kids furniture Co. ,Room Magic is the name you can find it on the net, so I have about 100 boards 33' by 20' 3/4 inch solid birch so I have many speaker projects in mind. Quote Link to comment Share on other sites More sharing options...
BEC Posted April 1, 2008 Share Posted April 1, 2008 "Anyone know the Eminence part # on that 4 ohm 15" woofer?" I don't think Eminence makes any 4 ohm 15 inch woofers except as special order exclusively for Klipsch and ..... well, for me. Bob Quote Link to comment Share on other sites More sharing options...
homemadeheresy Posted April 1, 2008 Share Posted April 1, 2008 I think the Eminence Kappa 15c is a 4ohm 15" woofer...... Quote Link to comment Share on other sites More sharing options...
BEC Posted April 1, 2008 Share Posted April 1, 2008 I think the Eminence Kappa 15c is a 4ohm 15" woofer...... Looks like you are right. I missed the 15c. Bob Quote Link to comment Share on other sites More sharing options...
kg4guy Posted April 2, 2008 Author Share Posted April 2, 2008 Bob how efficient are the 4 ohm 15's you have looks like the Kappas are 100.5 db 1w/1m? Quote Link to comment Share on other sites More sharing options...
BEC Posted April 2, 2008 Share Posted April 2, 2008 According to Eminence, the 15C is 98.1 db and claims 63 to 2800 frequency response. Mine are based on the K-33 with sensitivity of around 96 db. Bob Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 2, 2008 Share Posted April 2, 2008 Kg: It may be that you have a very good performing woofer, but, again, just need to match the outputs of the other drivers (the job of the autoformer on the old Klipsch networks). The loudspeakers you made should still be quite efficient, even if you have to drop the tweeter and midrange outputs again. The nature of the autoformer makes quick attenuation difficult, but it can be done. A mixed order network can sometimes even make a difference, but you have to do a little work for that. The kind of network you have is simple in that there aren't added elements such as impedance equalizers, notch filters, and so forth. In other words, the network is designed around the impedance of the drivers, the desired crossover frequency, and the amount of attenuation (which, considering how the autoformer works, also influences the refleced impedance) -- only. Still very simple. Thus, if you are using a single inductor in series with the woofer, using a slightly higher order network in the tweeter and midrange branches may offer slightly higher insertion loss, which may provide the balance you are looking for, which offering some of the subjective benefits of a sharper cutoff. And this brings us back to your original question about the addition of inductors in the tweeter and squawker. It's the same idea I used in building my own new networks for Klipschorns. But absolutely try another woofer. If you can find something to balance out the system that way, it will be easier for you. However, if all you need is a tiny bit more attenuation in the tweeter and midrange, Bob offers an autoformer with finer steps of attenuation than the T2A. You just have to keep in mind that changes in steps of attenuation on the autoformer alter the previous balance of reflected impedance. A swamping resistor can be used so that tap changes can take place without changes to values in capacitance, but whether you like what that does is something you would have to try. Still another method: Design a crossover for the ACTUAL impedances of the tweeter and midrange (such as a 12 or 18dB/octave), and use a variable L-pad (like the old Altecs and others) to balance the drivers. An L-pad is not technically part of the crossover, but rather a means to balance the drivers. You would read in many books that the L-pad (whether variable or fixed) should be installed AFTER the crossover. It's just a volume control that maintains the impedance of the driver regardless of amount of attenuation. Since the impedance is maintained constantly, there is no need to change the amount of capacitive reactance you need for the desired crossover frequency. You just turn the drivers down so they match each other and the woofer. Or again, find a woofer you like better -- whichever you prefer.....and have fun. Erik Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 2, 2008 Share Posted April 2, 2008 Image above shows an autoformerless approach using fixed resistor-based attenuation. This is the mixed-order network I built for my Klipschorns with home-made coils (which I could wind for the EXACT amount of inductance I wanted -- since the precise calculated value isn't available). I know of others who solve that problem simply by buying a larger value, and then unwinding it as needed to achieve the inductance they want. The network above uses a 4000Hz crossover point for the tweeter at a slope of 18dB/octave, a very focused band-pass on the squawker, and a simple but very robust choke in series with the woofer. This next one shows what a variable L-pad looks like. It's a network that in design is much like the ALK Universal (I built it with parts I had on hand as an experiment), but uses the variable 50 Watt L-pad shown with a black knob. I tried this with an extremely low powered output-transformerless amplifier, and the results were terrible. With a more powerful amplifier, it was much much better. The crossover point in this one is 6kHz. Just to show you some alternatives. Since this type of control maintains the impedance of the driver (16 ohms) that's the value of impedance that's used in calculating the capacitance needed at the chosen crossover frequency. In other words, no need to change caps when all you want to do is turn down the volume on the squawker. Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted April 2, 2008 Share Posted April 2, 2008 Oops -- sorry, that was the breadboard design for the first one I posted. This is where it started out, and I got really excited about how it sounded and fine tuned values a bit from there. This should be the one with the variable L-pad (at least I still think I have that picture) edit: The network to the left is the type A . Erik Quote Link to comment Share on other sites More sharing options...
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