Guest David H Posted March 28, 2014 Share Posted March 28, 2014 (edited) JBL's reference to the loosely wound caps. Dave Edited March 28, 2014 by GotHover Quote Link to comment Share on other sites More sharing options...
djk Posted March 28, 2014 Share Posted March 28, 2014 (edited) Some of Timbers' talk about battery bias make no sense at all, especially his comments likening it to crossover distortion in an amplifier. With automated capacitor winding machines it's not a big issue to maintain the proper winding tension, neither to loose nor too tight. The winders are so accurate they generally progran 5% caps to be near the low end of the tolerance to save material, this makes it easier to add a small bypass and keep the value where you need it. Edited March 28, 2014 by djk Quote Link to comment Share on other sites More sharing options...
Schu Posted March 28, 2014 Share Posted March 28, 2014 (edited) Dean, have you had the opportunity to compare the results of the battery bias network to those networks you build with premium components? I wouldn't expect a metallized or film type to sound like a paper in oil or wax impregnated stacked film, regardless of what you do to them. Those capacitors sound really different to me, almost ethereal. that is a perfect word to describe what it is being heard with Jupiters (and I am sure it would be the same with some other premium grade units)... Ethereal. I was always slightly skeptical about what would be gained by going with a cap modernization and how much of that modernization would be both audible and beneficial to the sound I wanted... but after making the difficult decision (based on the diminishing returns argument) to go in the premium direction, I was very very thankful I did so. Over OEM and some other re-Cap setups I have heard, there really was a marked difference in spacial qualities of the Jupiters cap's. It was the kind of upgrade you do that completely and legitimately justifies the cost IMHO... Yes I know I have a dog in this race, but I also know what I hear is vastly different in listening pleasure. Edited March 28, 2014 by Schu Quote Link to comment Share on other sites More sharing options...
Schu Posted March 28, 2014 Share Posted March 28, 2014 (edited) it seems a lot of what I am reading is an exercise in marketing... while I don't know a lot about what is being produced, I do know about branding and marketing. There needs to be a very distinguished an easily discernible difference in products in a particular line otherwise your customers begin to suffer from branding confusion issues that arise due to the fact that there is not enough distinction between a unit in the line that costs less, and those units in the line that might be better performance wide but do not justify the additional costs (at least in the end users mind). Overall, it is always much better to offer "less" to the customer as long as there is a measurable difference between those products. When a product line becomes "bloated" (specially with closely matched products) you begin to "cannibalize" your better end goods in favor of the more attractive price point items... this is an issue because for the most part, you best margin is usually skewed towards the "better end" goods. Edited March 28, 2014 by Schu Quote Link to comment Share on other sites More sharing options...
Deang Posted March 28, 2014 Author Share Posted March 28, 2014 Some of Timbers' talk about battery bias make no sense at all, especially his comments likening it to crossover distortion in an amplifier. With automated capacitor winding machines it's not a big issue to maintain the proper winding tension, neither to loose nor too tight. The winders are so accurate they generally progran 5% caps to be near the low end of the tolerance to save material, this makes it easier to add a small bypass and keep the value where you need it. Engineers deal with complex things. They are then expected to explain those things in such a way that a layperson can understand. Analogies are a good way to do this. Sometimes they work and sometimes they don't. The DC biasing of capacitors in crossover networks is now over 20 years old. With that in mind, his comment regarding the differences between capacitors in how they were wound may not be out of place. Quote Link to comment Share on other sites More sharing options...
Deang Posted March 28, 2014 Author Share Posted March 28, 2014 JBL's reference to the loosely wound caps. Dave "It has been established that capacitors that are more tightly wound have better transient response than those that are wound more loosely." - G Timbers Timbers was only saying that the tighter a capacitor is wound, the better the transient response is. He made a comparsion between those "more tightly wound" and those "wound more loosely". He never said anything about "cheaply built loose wound caps". I think he was just speaking in relative terms. IOWs, I don't think it's accurate to associate the amount of tension used to wind a capacitor with its quality. In fact, if the film isn't thick enough for the high level of tension employed, the film will stretch and create lesions, which causes low level arcing within the cap. This is the premise behind self-healing capacitors, and though marketed as a desirable quality, it's not a situation you want in high efficiency horn systems, because it translates into noise. So, how tight a cap is wound is no real indication of its quality. Quote Link to comment Share on other sites More sharing options...
Deang Posted March 28, 2014 Author Share Posted March 28, 2014 (edited) Battery bias'ed, or charge coupled has got the interest of a lot of DIY folks. what is interesting....collectively...and even on this forum...folks are removing the battery because once charged...for the current music session...they want to break their ground reference connection that exist as a result of the traditional bais or charge approach. I have read this comment at least two dozen times and I simply don't understand what you're trying to say. It sounds like you're saying that there are those who would like to remove the battery to hear their networks in a normal state, but can't because the JBL method ties the battery back to common. If so, this doesn't make any sense, because as I explained earlier, once the capacitors are charged, they pretty much stay that way unless you completely discharge them, which isn't as easy as one would think (see my earlier comments on DA and "memory effect"). Even still, your assumption is wrong. Thaddeus, nor the two other beta testers have removed their batteries. Mike stehr has decided to listen for a while first before inserting the battery, and I'm sure once he puts it in, it will stay in, unless he decides to rebuild his networks. with a bridge implementation...there is no need to remove the battery for the listening session once charge....that's because in bridge implementations there is no ground reference...and obviously....audiophile DIY folks feel the need to remove the ground reference for a reason. The idea here is to bring the attributes of high end film types to the sound by using affordably priced capacitors. The design requires a battery and a handful of resistors. The battery goes in, and should stay in until it needs to be replaced. I've studied this ad nauseum, and there is absolutely no down side to tying the negative side of the battery back to common. At least a half a dozen, well established and respected loudspeaker manufacturers have used this method in their high end products without any problem. This fixation on a "ground reference" has no relevance to the goals of the design. Edited March 28, 2014 by DeanG Quote Link to comment Share on other sites More sharing options...
djk Posted March 28, 2014 Share Posted March 28, 2014 "This fixation on a "ground reference" has no relevance to the goals of the design." I agree, but will take the time to compare with the bridged method (even though I think it will be a waste of my time, I'm willing to try it out). Too tight of a tension leads to an 'onion' shape and carbon deposits from self healing, and it can also make the capacitor microphonic. Correct tension depends on the thickness of the film, and is usually in the range of 300gm~1200gm. "Analogies are a good way to do this. Sometimes they work and sometimes they don't." I agree, and I still don't like this one. Basically we are shifting the zero-crosing point by 9V, at that level there is enough signal to cover up the noise created by the dielecric discharge issue. IIRC, Infinity used a higher voltage (18V), but they are much less efficient as well. BTW, oil filled caps are generally made with a lower tension, and the oil seems to damp things a bit. The JBL caps made by Electrocube in the 70's were in a sand-filled paper tube sealed with wax, well damped and not microphonic. I think they used a low temperature Bismuth alloy solder on the attachment points. Quote Link to comment Share on other sites More sharing options...
Deang Posted March 28, 2014 Author Share Posted March 28, 2014 (edited) "I agree, but will take the time to compare with the bridged method..." Are you out of your mind, we might have to eat crow. So, I'm ordering a cease and desist! : ) Edited March 29, 2014 by DeanG Quote Link to comment Share on other sites More sharing options...
Guest David H Posted March 29, 2014 Share Posted March 29, 2014 Are you out of your mind, we might have to eat crow. So, I'm ordering a cease and desist! : ) That's funny. Dave Quote Link to comment Share on other sites More sharing options...
djk Posted March 29, 2014 Share Posted March 29, 2014 "we might have to eat crow." I doubt it, I'm just trying to seem fair by offering due consideration to their idea. Quote Link to comment Share on other sites More sharing options...
jcmusic Posted March 29, 2014 Share Posted March 29, 2014 Dean, Where is this list to get on for your xovers? Which xovers are we talking about here? What setup are they designed for? Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted March 29, 2014 Share Posted March 29, 2014 "It has been established that capacitors that are more tightly wound have better transient response than those that are wound more loosely." I wonder if that applies to forum members as well. Quote Link to comment Share on other sites More sharing options...
Deang Posted March 29, 2014 Author Share Posted March 29, 2014 Lol, I think you might be on to something Carl. Quote Link to comment Share on other sites More sharing options...
Schu Posted March 29, 2014 Share Posted March 29, 2014 "the response of a system to a change from equilibrium" I had to look that up. Quote Link to comment Share on other sites More sharing options...
mike stehr Posted March 29, 2014 Share Posted March 29, 2014 I'll listen to the Cornwalls tonight using my Scott LK-48B integrated amplifier, without the batteries connected. The other night, the GF and I listened for 3-4 hours with the same set-up, CDP direct to a Magnavox SEP amp. My ears are pretty forgiving, or I get used to things rather easily. Having the networks re-capped alone with a tighter tolerance seems to tighten up the overall balance of the sound...from what I can hear. The thing I notice most is using the .39mH inductor in series after the autoformer. Sitting near-field, it gives just enough attenuation to the midhorn so it isn't so dominate. I have to turn up the volume slightly, but in return it opens up things a bit more. I can hear more bass now obviously, and strong deep bass considering the 3.5-4 watt per channel SEP amp. Things were sounding rather nice the other night, once things were all warmed up. The GF even noticed the difference. My ears may have gotten used to the "plastic" sound of the caps...I didn't notice it as much the other night. I've used Bennic and Dayton caps over the years, and I've never had any objections about the sound of those brands of capacitors. I did notice some slight bass bloat on a song, but I may have been clipping the little amp a bit. I'm curious if connecting the batteries may tighten up the bass a bit...I guess I'll find out soon enough... Mike. Quote Link to comment Share on other sites More sharing options...
Deang Posted March 30, 2014 Author Share Posted March 30, 2014 (edited) Jay, there is no longer any list. That is, nothing is being shipped around right now. I was down to two, and one lost interest and the other got lost when I shut down my private messaging. I deleted everything, thinking I had everything I needed in my inbox, which ended up not being the case. IOWs, I screwed up. Anyways, the last person in possession made a fair offer on the networks so I sold them. The network that was being sent around was the Super AA, recently renamed "The SuperX" because it can be ordered with different crossover points. Right now, I have a handful of beta testers trying out a few different stock crossovers which have been modified using a low pass coil for the midrange (first order electrical bandpass) along with DC biasing applied to the capacitors. You can go back about a dozen pages and catch up, or check out some of the provided links on the "News" page of my website. Edited March 30, 2014 by DeanG Quote Link to comment Share on other sites More sharing options...
jcmusic Posted March 30, 2014 Share Posted March 30, 2014 Ok thanks brother, I was thinking about trying something different while you had that option going on... Quote Link to comment Share on other sites More sharing options...
mike stehr Posted March 31, 2014 Share Posted March 31, 2014 "Right now, I have a handful of beta testers trying out a few different stock crossovers which have been modified using a low pass coil for the midrange (first order electrical bandpass)" I was wondering if that was some sort of bandpass filter. This mod works well for near-field listening from what I have experienced here. However, in a large room it may recess the midrange too much...but I'm just guessing here. Well I listened to the Cornwalls with the Scott LK-48B, the Maggotbox SEP console amplifier, and my Sonance Sonamp 275X3SE power amplifier...no batteries connected to the networks. The Scott LK-48B integrated always sounded nice with the Cornwalls, and the low pass coil on the midhorn even makes it nicer. I can crank the integrated up more with tone controls set almost flat, and the loudness compensation switch turned off. A nice balanced sound, with no midhorn shout. I connected the Marantz/Heart tube output CDP to the Sonance 275X3SE power amplifier direct. It's a conservative 75 watts into three channels. http://sonance.com/products/electronics/detail/234 It has sensitive inputs, but has input trim pots. I had to keep trim pots dialed down low, and keep the remote volume control at a minimum for good listening levels. The Cornwalls even have a good balanced sound quality with the SS amplifier with no tone controls. I still prefer the sound of tubes with my Cornwalls, but the Sonance doesn't sound half bad. And you can really pour the coal to the Cornwalls with the Sonamp if need be... The low pass inductor used with the midrange may help attenuate the slight accentuated midrange with my stereo DHT 2A3 amplifier, but I'll find that out later after I connect the batteries to the Cornwall B2 networks. I'm ready to connect the batteries now...I think I have a good idea on how the speakers sound currently... Mike Quote Link to comment Share on other sites More sharing options...
Marvel Posted March 31, 2014 Share Posted March 31, 2014 There's a schematic in the second post: https://community.klipsch.com/index.php?/topic/137696-battery-bias-on-caps/?hl=%2Bbattery+%2Bbiased#entry1545552 Quote Link to comment Share on other sites More sharing options...
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