Guest " " Posted April 18, 2011 Share Posted April 18, 2011 Basically a battery applies a very small amount of voltage to the crossover capacitors. You can google the claims by various manufactures that do this. My approach is a little different from the major manufactures........I use both the + and the - to charge the capacitors whereas everyone else is just using the +. It takes double the capacitors to do it my way. How does it sound? I have heard all the klipsch xovers from A to AL/AK-5, and a few of the popular boutique crossover upgrades for the Heritage line. This is the most amazing thing I have heard in a long time. This particular pair is going off to Marvel. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 18, 2011 Share Posted April 18, 2011 Here's the schematic. it takes four times the capacitors to bias them the way I have here, but the end result is amazing. Quote Link to comment Share on other sites More sharing options...
moray james Posted April 19, 2011 Share Posted April 19, 2011 I used to bias on the input caps on my Acoustat interfaces with a 1n4007 diode in series with a 4.7K resistor using the negative leg to supply the voltage to charge the caps. That was back in the early 1990's . Few parts cheap to do no battery to replace . Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 19, 2011 Share Posted April 19, 2011 interesting....in the crossover world..most folks are using 1 to 2 meg resistors. The batteries last pretty close to their shelf life since the current thru the 1 to 2 meg resistor is so low. Quote Link to comment Share on other sites More sharing options...
Marvel Posted April 19, 2011 Share Posted April 19, 2011 Does the one with the most parts win? I'm really looking forward to trying these out in my LS. I'm currently using some DHA2 crossovers, which, being constant impedance, work great with my 2A3 amps. Bruce Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 19, 2011 Share Posted April 19, 2011 if you want to compare to the DHA2, should I send you type A's? The below are type AA and the DHA2 are type A's. let me know. Quote Link to comment Share on other sites More sharing options...
Marvel Posted April 19, 2011 Share Posted April 19, 2011 Nope... I want to try the AAs with battery bias. Thanks for asking, though. [] Bruce Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 19, 2011 Share Posted April 19, 2011 OK, AA's it is...they will be shipped out in the morning. Quote Link to comment Share on other sites More sharing options...
moray james Posted April 19, 2011 Share Posted April 19, 2011 more current more bias kind of like pulling an IC into class A operation the more you pull it down the better within the limits of the device. You can do the same thing on you main filter caps in an amp, dosen't take up much realestate or cost much in parts. It's a good tweak. Pump those caps up. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
djk Posted April 20, 2011 Share Posted April 20, 2011 The capacitors with their DC resistance on the order of 10^12Ω pull no current with the DC bias, none, zip, nada. " You can do the same thing on you main filter caps in an amp, dosen't take up much realestate or cost much in parts. It's a good tweak. Pump those caps up. " You're not making any sense, the main filter caps are hooked straight to the rails, how do you pump them up? Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 20, 2011 Share Posted April 20, 2011 The capacitors with their DC resistance on the order of 10^12O pull no current with the DC bias, none, zip, nada. You're not making any sense. small amount of current as in normal film capacitor leakage.....which all caps have....so even a good within spec cap, once installed, would have a small amount of current flowing thru it as a result of the leakage...... Quote Link to comment Share on other sites More sharing options...
djk Posted April 20, 2011 Share Posted April 20, 2011 Sure, but there is likely to be more leakage from your fingerprints on the part, and internal to the battery leakage, than in the dielectric of a high quality film cap. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 20, 2011 Share Posted April 20, 2011 thats probably why some manufacturers call this "battery charged " instead of "battery bias". "battery charged" would avoid the current debate. both use the same circuit approach. Quote Link to comment Share on other sites More sharing options...
dkalsi Posted April 20, 2011 Share Posted April 20, 2011 I think JBL does this in their higher end models. I build "charged-coupled" crossover for my JBL 4345 clones - (see below). I don't know if they sound better than the non-charged versions because I have never heard a non-charged version. I decided to build the charged couple versions sole based on the positive reviews I've read online. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 20, 2011 Share Posted April 20, 2011 very nice layout. There are a handful of manufacturers that do charge coupling or battery biasing in their xovers. noticed you have one battery charging 4 sets of caps. I was wondering about if that was doable. all of the schematics I saw had a separate battery for each cap set. Quote Link to comment Share on other sites More sharing options...
moray james Posted April 20, 2011 Share Posted April 20, 2011 Dennis it has been a lot of years since I did this and perhaps the IC bias analogy was not a very good or technically correct one, I am not a technical electronics guy. I figured the guy who showed me how to do this knew about electronics design and he seemed to feel that a charge bias was a good idea and those are the values he used. I have been trying to remember the discussion we had about this but it was around twenty years ago and it's not clear but it seems to me he figured a hard bias was a good thing. I have drawings somewhere (that was long before I had a computer) for the configuration used on an amp but where, would be a task to look for them now. I do remember when he modified my Meitner MTR 101 mono blocks I liked the results. Ed's still in town but I don't see him much these days. Sorry for not answering your question. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 20, 2011 Share Posted April 20, 2011 battery bias of transistors was very popular in the early 80's. I remember making the mod to a dynaco st-80 kit I put together. your resistor and diode method seems to ring a bell. Quote Link to comment Share on other sites More sharing options...
Guest David H Posted April 24, 2011 Share Posted April 24, 2011 Hey Fritz, I redrew your Schematic in paint, please check it for accuracy. Dave Quote Link to comment Share on other sites More sharing options...
Guest " " Posted April 25, 2011 Share Posted April 25, 2011 That looks real good....thanks Quote Link to comment Share on other sites More sharing options...
Marvel Posted April 26, 2011 Share Posted April 26, 2011 After dealing with the local P.O., I got the crossovers yesterday (Monday). They survived the trip, and are safely tucked away in the back of my LS. I am in the middle of rearranging some gear, so I can't give a listen yet but will post as soon as I can. Thanks go out to Mike for wiring these up and sending them to me. Bruce Quote Link to comment Share on other sites More sharing options...
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