michiganpat Posted April 6, 2015 Report Share Posted April 6, 2015 thanks kent, I'll probably should just break down and buy one Link to comment Share on other sites More sharing options...
ra.ra Posted April 7, 2015 Report Share Posted April 7, 2015 Good advice from Kent on the meter, but one more detail. Be sure to check the range of capacitance measurable - - don't be a doofus like me and get a device that only measures up to 20 uF - - find a simple meter that measures at least up to 200 uF, if not more, to make it far more useful in your projects. Link to comment Share on other sites More sharing options...
DavidR Posted April 7, 2015 Author Report Share Posted April 7, 2015 This is the one I got thru Parts Expresshttp://www.parts-express.com/digital-handheld-capacitance-meter--390-735 Link to comment Share on other sites More sharing options...
johnfalc Posted April 8, 2015 Report Share Posted April 8, 2015 Here's what I found when I recapped my AR-90s a couple of years ago. Perhaps helpful information...http://falcons.dyndns.org/links/open/audio/ar-90/ar-90_cap_replacement.jpgHappy Listening! Link to comment Share on other sites More sharing options...
DavidR Posted April 9, 2015 Author Report Share Posted April 9, 2015 So I called Erse today (thanks to ra.ra posting the addy and tele) and asked about the 250V 200uF PulseX cap they used to have on their website and still shows on their Corp website (Gabriel). They no longer make it so I'm unable to parallel a 150uF and 200uF for the 350 cap. He recommended (2) 180uF paralleled. He also thought the 82uF would work in place of the 80uF.What are the thoughts on whether this will be acceptable ? Link to comment Share on other sites More sharing options...
Pete B Posted April 13, 2015 Report Share Posted April 13, 2015 DavidR, said:"As to NPEs Pete B states that there aren't any NPEs available in the U.S. that are any good (maybe not is exact words); "I can't think of anytime I've ever said this, in fact I do remember saying that I have 15+ year old Bennics that still measure fine. I believe that Erse are fine also. I would not trust no name or off brand names since there is a lotof junk being made today.I don't believe that any are made in the US and I don't remember making any statement like that.I might have said that you'll never match the low ESR of the big cans in the ARs with any single "normal" NPE cap.The big cans have multiple attachment points to the plates. You'd probably need 10 smaller caps in parallel tocome close to the ESR of the big cans. Link to comment Share on other sites More sharing options...
Pete B Posted April 13, 2015 Report Share Posted April 13, 2015 So I called Erse today (thanks to ra.ra posting the addy and tele) and asked about the 250V 200uF PulseX cap they used to have on their website and still shows on their Corp website (Gabriel). They no longer make it so I'm unable to parallel a 150uF and 200uF for the 350 cap. He recommended (2) 180uF paralleled. He also thought the 82uF would work in place of the 80uF.What are the thoughts on whether this will be acceptable ?Figure out the percentage difference and if you are within 5% I'd call it good enough. Link to comment Share on other sites More sharing options...
DavidR Posted April 24, 2015 Author Report Share Posted April 24, 2015 I've been out of action for a bit.Thanks for the response Pete.I've been offline for a while so I'm just seeing this now.Would I be better off going (higher) with (2) 180uF equaling ~360uF or going (lower) with a 180 + 160uF equaling ~340uF?Perhaps it doesn't matter. I was just thinking if that zobel is filtering higher frequency noise then going lower might be the better way to go. But that's just a total guess. https://www.trueaudio.com/st_zobel.htmI don't know the drivers/woofers L(e) in henries to do the calc. Link to comment Share on other sites More sharing options...
donquixote99 Posted April 25, 2015 Report Share Posted April 25, 2015 Looking at Erse's offerings online, it seems you could try 2 120's and a 110, and that would nail it. Link to comment Share on other sites More sharing options...
ra.ra Posted April 26, 2015 Report Share Posted April 26, 2015 There has been a great deal of healthy chatter about caps in this forum lately, but I'd be interested to hear a convincing argument for why anyone would feel compelled to shell out such substantial $$$ for 350uF Erse Pulse-X caps in the woofer circuit. From my quick glance, any of the mentioned combinations of paralleled caps (180+160 or 180+180 or 120+120+110) will run close to $100 per cabinet simply for the woofer capacitors. Before committing to that type of expenditure, I would think it would be prudent to first confirm a solid reason (measurements?) for replacement, and even if those findings do stand up, I'd be strongly inclined to look at two 6% Erse npe's (200+150uF) for about $4 per cabinet. (edit: ....and welcome to this forum, donquixote99.) Link to comment Share on other sites More sharing options...
DavidR Posted April 26, 2015 Author Report Share Posted April 26, 2015 Believe me, I'd be lying if I said the cost of film caps for the woofers isn't a concern. Well over $200 (for the pair) with shipping. One reason for considering the 180 + 160 is a small savings. NPE may very well be the route to go. Waiting for the conclusion to the cap accuracy thread and how a hobbyist with a 'simple' capacitance meter can determine 'good' caps vs out-of-spec.I believe I've read that the woofer cap in the shunt/parallel position doesn't really affect the sound. Its just shunting frequencies to ground. Advantage to going with a film cap is it will not likely have to be changed, ever, and a better more accurate performer for the job at hand. Link to comment Share on other sites More sharing options...
donquixote99 Posted April 26, 2015 Report Share Posted April 26, 2015 thanks for the welcome, ra.ra, and yes, I was ignoring the cost factor...with some effort..... Link to comment Share on other sites More sharing options...
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