JKent Posted November 5, 2019 Report Share Posted November 5, 2019 Stimpy, Of course you are right. My comment was more a "rule of thumb" because were it not for your helpful comment earlier, many people would not know which caps are series. Also, low-value film caps are pretty inexpensive. The 8uF PeX for example is about $1.50. And the Carli you used (sadly NLA) was $2.35. Kent Quote Link to comment Share on other sites More sharing options...
ra.ra Posted November 5, 2019 Report Share Posted November 5, 2019 6 hours ago, DavidR said: Not our $$$; not our gear, not our ears, not our concern. David, your terse response to my comments and to suggest I was "aiming" at Larry makes me think you've missed my points, so perhaps I could have worded my earlier post better. There was no intended snark or criticism - - - in fact, I have great respect for what Larry has done here and his posts routinely remain among my very favorites to read in this forum. Aside from praising his new crossover work, I was trying to bring up two issues that I felt might address some of the OP's initial questions and parameters. Issue One: I remain very curious to learn about Larry's personal audio evaluations resulting from the terrific circuits he has built for his AR-58s resto-mod project. Adapted boards, new switches, high quality caps and resistors, perhaps soon a subjective A-B test....... This appears to me to be one of the very core issues discussed in this forum, and therefore I think it is "our concern". Because the OP very clearly stated an explicit budget for this project, the issue of cost is also very much a germane topic for this thread. My curiosity was purposely stated to not be so crass as to ask "How much did this cost?", but I feel that a statement to the OP such as "this solution can be purchased within your budget" could be very helpful, not only to him but to all readers. Three or four other prescriptions with excellent solutions for re-built crossovers have already been presented with great detail - - including rough costs - - and I was merely pointing out that this information was lacking in the one post and therefore left a more comprehensive comparison of the various suggestions unavailable to us. On 11/1/2019 at 10:33 PM, Darren James said: Question, would you replace the caps on principal? You've received a lot of great advice and experience in these responses, but this question remains the crux of the biscuit. Mostly from Stimpy, he has best tried to address your question with his own personal philosophy and tastes, and I think he offers some solid advice here when it comes to making value decisions about how to prioritize some component purchases. Darren, please follow up and show us how your project is progressing. Quote Link to comment Share on other sites More sharing options...
Aadams Posted November 5, 2019 Report Share Posted November 5, 2019 If cost benefit is a genuine concern to the OP, it might be helpful to tell him the magnitude of improvement in sound quality that comes from using the more expensive solutions as opposed to using all Dayton NPE, for example, which would very inexpensive by comparison and merely replicate the original design and sound. Adams Quote Link to comment Share on other sites More sharing options...
ar_pro Posted November 5, 2019 Report Share Posted November 5, 2019 On 11/3/2019 at 8:27 PM, JKent said: Erseaudio.com 4uF PeX film $0.86 OR 3.90μF 250v PulseX - Metallized Polypropylene Film $1.33 8uF PEX film $1.48 or 8.20μF 250v PulseX - Metallized Polypropylene Film $2.08 24.0μF 250v PulseX - Metallized Polypropylene Film $4.36 40uF NPE $0.38 100uF NPE $0.71 Could be $16 for both The 100uF poly cap is especially notable, at about $27.00 for the PulseX version against 71 cents for the NPE. Changing out crossover parts - caps, resistors, terminals, wire, binding posts, level controls, etc. - is an aspect of speaker restoration that stays within the lines of the original design, but also allows for the "what if" possibility of utilizing components that might not have gotten past the original bean counters those many years back. That these ancient designs are still competitive with high-quality modern speakers is extraordinary, and that they can be tinkered to improvement with a relatively small investment for parts and some simple soldering is doubly so. The practical application of experience, modifications, parts substitutions and artful technique is my favorite part of this forum - it's always a pleasure to see how things are done. Quote Link to comment Share on other sites More sharing options...
lARrybody Posted November 5, 2019 Report Share Posted November 5, 2019 Almost done with the second crossover board, but this is Darren James thread about his AR 91 restoration. I just wanted to add the possibility that some of the original Components may well be in specifications. I have a Mastech capacitance meter and one of those inexpensive circuit board devices with the readout screen. Also a Fluke 177 that test capacitance that I did not use. The original 100uf Callins cans tested out 97.04 and 99.9 respectively. These may well be just fine. The 40uf CRX black with red ends tested 46.68 and 46.5. The silver 24uf CRX caps were way off at 57.85 and 55.2. The 8uf black and red CRX tested 8.1 and 8.55. The white 4uf Mexico caps 5.02 and 5.03. I don't know if Darren James can test his original caps,but mine seemed acceptable except for the 24uf midrange cap. I sure hope Darren James keep us informed with his progres with his 91's. I won't post anymore about the my 58S's until they are complete. Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 5, 2019 Author Report Share Posted November 5, 2019 good mix from all of you..... thanks for the thoughts.... I will take it all into account, then choose so I only have myself to blame if it shits.... LOL So, on the parallel ones (shunts?) these are second level action right? So the series ones should be as clean and top notch as best possible... Darren Quote Link to comment Share on other sites More sharing options...
Stimpy Posted November 6, 2019 Report Share Posted November 6, 2019 6 minutes ago, Darren James said: good mix from all of you..... thanks for the thoughts.... I will take it all into account, then choose so I only have myself to blame if it shits.... LOL So, on the parallel ones (shunts?) these are second level action right? So the series ones should be as clean and top notch as best possible... Darren Hey Darren, We don't mean to be confusing. We're just enthusiastic. But, remember, whether you choose film or NPE, or a mix, they'll be an upgrade. Don't stress too much over it, as there is no wrong choice. As to your questions, yes the parallel shunt caps are "second level". NPE is fine. The 4.0 and 24uF caps are the series caps. To me, they deserve "top notch". Though, as mentioned, electrolytic is fine too. But, even inexpensive poly's are great. And they won't ever need to be replaced. Good luck. P.S. I literally read and researched for months, when deciding on caps for my AR-90s. So, you're not alone. Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 6, 2019 Author Report Share Posted November 6, 2019 8 minutes ago, Stimpy said: Hey Darren, We don't mean to be confusing. We're just enthusiastic. But, remember, whether you choose film or NPE, or a mix, they'll be an upgrade. Don't stress too much over it, as there is no wrong choice. As to your questions, yes the parallel shunt caps are "second level". NPE is fine. The 4.0 and 24uF caps are the series caps. To me, they deserve "top notch". Though, as mentioned, electrolytic is fine too. But, even inexpensive poly's are great. And they won't ever need to be replaced. Good luck. P.S. I literally read and researched for months, when deciding on caps for my AR-90s. So, you're not alone. Passionate...... we'll call it passionate..... I get it!! I did the caps on a pair of JBL CF150's and it was like new speakers... I have done early B and W and seen no difference, I've done some Marantz Imperial 6's and huge change... I swear it is all hit and miss as far as a change.... But it does help to do the best you can... then you can go onto other shit as the reasons for shitty sound.... LOL thanks, Darren Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 6, 2019 Author Report Share Posted November 6, 2019 here are some pics of the woofs...... do pics have to be a certain size? Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 6, 2019 Author Report Share Posted November 6, 2019 some of the gooey mess I have to clean up.... Quote Link to comment Share on other sites More sharing options...
JKent Posted November 6, 2019 Report Share Posted November 6, 2019 1 hour ago, Darren James said: do pics have to be a certain size? About 100KB works well. And I usually size mine to about 6 to 8 inches on the long side. Quote Link to comment Share on other sites More sharing options...
DavidR Posted November 6, 2019 Report Share Posted November 6, 2019 3 hours ago, Darren James said: some of the gooey mess I have to clean up... The 'gluer' at the AR plant that day went crazy with the hot melt. One of my 90's is similar. Dribble a small amount of isopropyl/rubbing alcohol on the old hot melt glue. Let it sit for 5 to 10 mins and then go at it *slowly* with a small flat screwdriver and small putty knife. See you Friday afternoon. Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 8, 2019 Author Report Share Posted November 8, 2019 existing caps state.... 100 uf / this cap gave a reading of nil. 00.00 40 uf / 52.45uf 24uf / 32.33uf 8uf / 9.12uf 4uf / 7.67uf so this is where one speaker is at..... not for long... Quote Link to comment Share on other sites More sharing options...
Stimpy Posted November 8, 2019 Report Share Posted November 8, 2019 26 minutes ago, Darren James said: existing caps state.... 100 uf / this cap gave a reading of nil. 00.00 40 uf / 52.45uf 24uf / 32.33uf 8uf / 9.12uf 4uf / 7.67uf so this is where one speaker is at..... not for long... Wow...! Quote Link to comment Share on other sites More sharing options...
DavidR Posted November 8, 2019 Report Share Posted November 8, 2019 From what I seen it's believable. Did the 100uF read OL or 0.0 ? Did you test them at 1kHz ? Quote Link to comment Share on other sites More sharing options...
Darren James Posted November 8, 2019 Author Report Share Posted November 8, 2019 Here's one unit..... DavidR lives down the street.. (who woulda thought!) and gave me some 4's and 25's so I'll swap out the double up 2's and 12's later.... I have to say I am very pleased with the difference... So is the neighbors.... apartment living has its down side.... Thanks again everyone!! Quote Link to comment Share on other sites More sharing options...
DavidR Posted November 8, 2019 Report Share Posted November 8, 2019 More like across town. LOL Do both xover boards have the same copious amounts of glue? Geez........... Quote Link to comment Share on other sites More sharing options...
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