AJR Posted January 25, 2012 Share Posted January 25, 2012 Hi there, I want to modify the latest version of the Heresy III , with that big crossover inside. This crossover seems to be very complex. And the parts are very cheap looking, those yellow cap's...or coils. Is there somebody who has the layout of that filter, or is there somebody whic\h already has changed that filter, with very good (expensive...) capacitors, etc? Regards, AJR Quote Link to comment Share on other sites More sharing options...
moray james Posted January 25, 2012 Share Posted January 25, 2012 AJR: welcome to the forum. I like the way you think. Sounds like a fine plan to me. Yave you taken a parts count in there that would be a good first step. You can draw the schematic out when you do that. Maybe borrow an inductor meter and lift a leg of each coil when you measure. Film and fiol caps would be a fine upgrade. Large low DCR inductors would be nice also but notgoing to fit if you use air core. What are you thinking? Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
Guest " " Posted January 25, 2012 Share Posted January 25, 2012 Those crossovers are fine. The only tweak I would do is to add a polycarbonate by pass capacitor to each existing capacitor. I would use a polycarbonate capacitor at 1% of the existing capacitor values. Quote Link to comment Share on other sites More sharing options...
Chris A Posted January 25, 2012 Share Posted January 25, 2012 And the parts are very cheap looking...From an engineering perspective, it's the sound the speakers make that is important - not their looks. But if your intent is to tinker, I'd recommend starting with cheaper second-hand Klipsch speakers. Old capacitors in those older units usually need to be replaced after they are 15-20 years old. You could also bypass the passive crossovers in your H-III's and bi-amp or tri-amp them--this would improve sound reproduction. Chris Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted January 25, 2012 Share Posted January 25, 2012 Doesn't look that cheap to me. Quote Link to comment Share on other sites More sharing options...
StephenM Posted January 25, 2012 Share Posted January 25, 2012 From an engineering perspective, it's the sound the speakers make that is important - not their looks. +1. FWIW, I would caution against this project. It's one thing to modify a speaker after you've identified a problem, worked out a fix (while trying to minimize unintended consequences of said fix...), implement the fix, and then hopefully measure the results, thus verifying the efficacy of the fix. It's a whole different animal to replace all the crossover components because they look cheap... Quote Link to comment Share on other sites More sharing options...
tigerwoodKhorns Posted January 25, 2012 Share Posted January 25, 2012 You can easily fix the yellow caps with one of these: Quote Link to comment Share on other sites More sharing options...
moray james Posted January 25, 2012 Share Posted January 25, 2012 To help maintain the sensibility of those who feel the suggestion of such a project is a "Heresy" why dont you get a new set of terminal cups and build up a brand new network on a board to place on the bottom of the cabinet. You will require the added room if you go with S.O.T.A. inductors which will be very large. Then you can compare your selection of parts to the stock networks and sell which ever one you like the least. While you are in the cabinet you can brace the heck out of it too. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
StephenM Posted January 25, 2012 Share Posted January 25, 2012 While you are in the cabinet you can brace the heck out of it too. While I like an inert cabinet as much as the next guy, won't altering the box volume by adding lots of bracing potentially introduce new problems? Quote Link to comment Share on other sites More sharing options...
Islander Posted January 25, 2012 Share Posted January 25, 2012 Not only that, the Heresy III cabinet panels aren't that large and are reasonably thick, plus the front and rear boards are solidly attached, so I don't think there are too many complaints about panel flex, unlike the much larger La Scala side panels, for example. Quote Link to comment Share on other sites More sharing options...
moray james Posted January 25, 2012 Share Posted January 25, 2012 you have about 1.9 cu. ft. of volume inside a Heresy give or take. Shifting that 10 % will not have any appreciable impact even if you ate up 15% it's not going to shift much . Consider that you are going to redamp the cabint which will in all likelyhood make up for any small loss of volume and also keep in mind Heresy don't make bass to begin with anyway so a small loss makes little difference, at worst the bass will end up about the same as a Heresy or a Heresy ll. I plan on testing some unusual damping with perlite which I have tried once before with excellent results, I my just end up with slightly better bass even with the loss of volume due to brace work. Remember that when you have a loose goose cabinet design like a Heresy or a cornwall and you then brace it well a lot of what people take for bass will be gone. Unbraced box walls flopping around can and do in many cases generate more bass tha the actual output of the driver. that's not bass that's distorted noise and you are well rid of it. A small example of this BBC style nonesence is the LS35A and other modern day designs such as the Harbeth. It is well documented that some unbraced cabinet designs can result in the cabinet walls actually radiating as much acoustical output asd the driver itself. The Heresy would have to be considered a offender in this respect. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
moray james Posted January 25, 2012 Share Posted January 25, 2012 Nothing personal but there is nothing solidly attached in a Heresy except the edges of the panels in the cabinet. The panels are only restricted in their range of motion by the inhearent stiffness or thickness of the material used and in this case that is 3/4" MDF. So as you can imagine there is little stiffness. Most people do not even realize that there is any panel flex until they are presented with a version which actually has little flex.Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
StephenM Posted January 25, 2012 Share Posted January 25, 2012 Out of curiosity moray, do you run any measurements before and after your modifications to verify the problems exist (significant panel flex) and that the result is up to snuff (not significantly impacting low end response)? Any tips as to how you'd go about effectively bracing a Heresy without significantly reducing box volume? Quote Link to comment Share on other sites More sharing options...
moray james Posted January 25, 2012 Share Posted January 25, 2012 I don't see this as being an attempt to fix a problem though totally unbraced cabinets should be considered a problem by all. People may argue that the box flex is factored into the intended sound of the cabinet and Harbeth would be one of those. I don't care two cents for this kind of messed up rational. I don't want to hear the cabinet distorting I only eant to hear the bass which is being generted by the loudspeaker. A hollow box is a problem in that it can do nothing but resonate at some number of frequencies determined by panel sizes, internal volume and the stiffness of the material used to build the cabinet.To answer your question no I don't bother to measure before or after because it was lousy befor and better after brace work. Not all that long ago I braced and stiffened a Quartet with 3/4"plywood braces which were 2.5"x 3/4" and one inch stringers. I re damped the inside of the cabinet with 5/8" thick high density fiberglass and then re tuned the passive using a 31.5 Hz. bass tone and weight to the passive.. I also dropped in a KLF20 woofer to replace the stock driver. The results are stunning and I don't think many here would believe the depth and quality of the resulting bass. I had been running two HSU VTF2 Mk ll subwoofers . The new cabinet and woofer generated deeper cleaner more articulate bass than what was being made by these to subs combined. Extension well into the 20's with the new speakers. None of this is scientific I agree but it works for me and that's all that matters. Below is a link to a thread with some pictures on the third and fourth pages of some internal brace work done on a pair of Quartets and a pair of KLF20 speakers. Hope this is of interest. Best regards Moray James. http://www.audiokarma.org/forums/showthread.php?t=372783&highlight=klf20 Quote Link to comment Share on other sites More sharing options...
StephenM Posted January 25, 2012 Share Posted January 25, 2012 I don't see this as being an attempt to fix a problem In this particular case, most certainly not. The only problem is that the XO parts do not appear to be fancy enough. There is no mention of any actual sonic problem, which is why I advise to proceed with caution. I've tried messing with speakers in the past, and I've had a little success (with help from an engineer with considerable insight on the speaker in question) and I've been burned for trying to mess with one of the best (IMO anyway) speakers I've heard. These days, I prefer to approach things from a scientific/engineering minded standpoint to avoid such mistakes. I can respect that you use your ears to tune your speakers to your preference, but it might not be a great idea to suggest to a new member with an unknown level of talent for tinkering with speakers to brace away. Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted January 25, 2012 Share Posted January 25, 2012 With all due respect, modifying the Heresey 3 as suggested is probably going to yield little or benefit. It will certainly decrease the value of the cabinet however. If you need to experiment (and we all do), I would suggest experimenting with geometry of the set up. Are they in corners, on the floor, near a wall etc.?This will have a far bigger and better impact than what some of the folks are advocating. In either case, good luck Quote Link to comment Share on other sites More sharing options...
Rick Posted January 25, 2012 Share Posted January 25, 2012 With all due respect, modifying the Heresey 3 as suggested is probably going to yield little or benefit. It will certainly decrease the value of the cabinet however. If you need to experiment (and we all do), I would suggest experimenting with geometry of the set up. Are they in corners, on the floor, near a wall etc.?This will have a far bigger and better impact than what some of the folks are advocating. In either case, good luck Agreed. And I certainly don't think there is anything "cheap" about the Heresy III crossover... Quote Link to comment Share on other sites More sharing options...
moray james Posted January 26, 2012 Share Posted January 26, 2012 What ever worksfor you is good. I don't see any reason for anybody not to build an upgraded crossover. I did suggest he keep the stock unis as such a reference if you will and I don't see any reason why anybody with the ability to brace a cabinet (any cabinet) should not. A shift of 10% cabinet volume for brace material is no big deal. It's not tinkering it's finishing the job that did not get finished for what ever reason. I happen to think the H3 is a fine speaker but that does not mean that it cannot be improved or should not be improved. You can always switch back at any time if you don't like what you have done. Its a great learning experience. You learn more from your mistakes than from your successes. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
moray james Posted January 26, 2012 Share Posted January 26, 2012 Your concern is a valid one and well worth noting. I would hope that anybody who embarks upon major modifications such as have been suggested would consider the impact of the changes being considered. As to the value of the cabinet I should think that would be a matter of perspective but yes as far as general re sale value would go it would have a negative impact. Personally I don't concern myself with that and it's not why I modify and if the next owner does not appreciate what I have done then they can purchase something stock. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
moray james Posted January 26, 2012 Share Posted January 26, 2012 I think the H3 crossover is a good one the best of the line so far. That said these are by no stretch of the imagination SOTA parts so there is no reason not to upgrade and expect improvements in performance. Best regards Moray James. Quote Link to comment Share on other sites More sharing options...
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