JKent Posted August 12, 2011 Report Share Posted August 12, 2011 Well, Pete, decided to go for the gusto and use the good inductors. Getting braver What the heck--only paid $50 for the speakers. Figuring in the refoam kit, new caps, resistors, inductors and misc these are still costing me well under $200. So even if I decide not to keep them I can probably sell them and at least break even.Here's what I ordered from Erseaudio: (2) EAC32-18-450 0.45mH 18ga EQ -Perfect Lay High Bond Air Core Inductor $9.30(2) EAC31-18-070 .07mH 18ga EQ - EQ – Perfect Lay High Bond Air Core Inductor $4.80(2) EAV75-14-1500 1.5mH 14ga XQ - Perfect Lay Air Core Inductor $44.60 Subtotal $58.70 Shipping $9.25 Total $67.95 So while I wait, think I'll make some cabinet braces per Carl's suggestion and clean up the veneer.I've decided that, except in extreme cases, it's better to just clean the cabinets with Howard Restor-a-Finish, leaving minor dings and scratches as "patina." Sanding and veneer do not make a good combination.Kent Link to comment Share on other sites More sharing options...
dynaco_dan Posted August 12, 2011 Report Share Posted August 12, 2011 The refoam job is finished. Came out quite well if I do say so. Still don't agree that the Masonite-ring version is "easy" compared to more conventional designs, but not as bad as I had feared.KentHi KentGlad your refoaming went well for you.I see an optical illusion, it looks like to 1/2 roll is outward, rather than inward.I've seen this before on ebuy, dunno why it appears that way.Maybe I should eaze up on my meds. LOL Link to comment Share on other sites More sharing options...
Doug G. Posted August 12, 2011 Report Share Posted August 12, 2011 Hi Vern!The same thing happens to me too with masonites. I usually have to take a second or third look to let the "correct" way lock in to my vision.I take meds too but they shouldn't be any of the kind to make me hallucinate (just blood pressure and anti-cholesteral drugs). Unless, of course, Kent has discovered a new, superior, half-and-half Advent refoaming method.\:^)Doug Link to comment Share on other sites More sharing options...
JKent Posted August 12, 2011 Report Share Posted August 12, 2011 I see an optical illusion, it looks like to 1/2 roll is outward, rather than inward.What?! You mean that's not how they go? Yes, they are inverted per originals.Finished the bracing: 2 oak braces front-to-back.Kent Link to comment Share on other sites More sharing options...
JKent Posted August 17, 2011 Report Share Posted August 17, 2011 Separated at birth? Never noticed this before but the OLA looks a LOT like the KLH Model Five: Bull nose frame, trim between the bull nose and grille, even the size. OLA is 14 ¼ x 25 5/8 x 11 ½. KLH Five is 13 3/4 x 26 x 11 ½ Link to comment Share on other sites More sharing options...
dynaco_dan Posted August 17, 2011 Report Share Posted August 17, 2011 Separated at birth? Never noticed this before but the OLA looks a LOT like the KLH Model Five: Bull nose frame, trim between the bull nose and grille, even the size. OLA is 14 ¼ x 25 5/8 x 11 ½. KLH Five is 13 3/4 x 26 x 11 ½ Hi KentSmall section of cabinets but both are attractive in appearance.You'd almost think that the same designer was involved with both of their design. LOL Link to comment Share on other sites More sharing options...
Doug G. Posted August 18, 2011 Report Share Posted August 18, 2011 OK, ready for it?They are pretty Kloss in appearence.Ba dum bum.Doug Link to comment Share on other sites More sharing options...
JKent Posted August 19, 2011 Report Share Posted August 19, 2011 They are pretty Kloss in appearence. :lol: Funny (to those who know how Henry pronounced his name).Built one new XO today. Thanks Pete for the encouragement and advice. Those new inductors are BIG and HEAVY compared to the weenie ones in there originally. Used Carli capacitors and stuck a bypass cap on the tweeter. Doubt it helps but it couldn't hurt. New Dayton "Audio Grade" resistor.Can't wait to get these finished now! But I'm dividing my time between these and the Pinnacle PN6+ Sally find.Kent Link to comment Share on other sites More sharing options...
dynaco_dan Posted August 19, 2011 Report Share Posted August 19, 2011 :lol: Funny (to those who know how Henry pronounced his name).Built one new XO today. Thanks Pete for the encouragement and advice. Those new inductors are BIG and HEAVY compared to the weenie ones in there originally. Used Carli capacitors and stuck a bypass cap on the tweeter. Doubt it helps but it couldn't hurt. New Dayton "Audio Grade" resistor.Can't wait to get these finished now! But I'm dividing my time between these and the Pinnacle PN6+ Sally find.KentHi KentWhen I was a subscriber to, The Audio Amateur magazine, there was a Walt Jung who wrote several articles.A Dynaco C-100 electrolytic capacitor type bank for the Dynaco 400, but it could be used for others.Almost every electrolytic capacitors that he wrote about had a small, such as 0.47uf capacitor, across it.I would need to review all my old back issues to be absolutely certain of this.Not too long ago I read something about this, it allows higher frequencies to pass.Maybe it is, AVA, Van Alstynes (spel) web site. Link to comment Share on other sites More sharing options...
JKent Posted August 20, 2011 Report Share Posted August 20, 2011 Not too long ago I read something about this, it allows higher frequencies to passYes Vern, that's the theory. I'm skeptical but the bypass caps are very cheap so why not?Kent Link to comment Share on other sites More sharing options...
Pete B Posted August 20, 2011 Report Share Posted August 20, 2011 Hi KentWhen I was a subscriber to, The Audio Amateur magazine, there was a Walt Jung who wrote several articles.A Dynaco C-100 electrolytic capacitor type bank for the Dynaco 400, but it could be used for others.Almost every electrolytic capacitors that he wrote about had a small, such as 0.47uf capacitor, across it.I would need to review all my old back issues to be absolutely certain of this.Not too long ago I read something about this, it allows higher frequencies to pass.Maybe it is, AVA, Van Alstynes (spel) web site.Hi Vern,Walt Jung is the author of "The OP Amp Cookbook" and I believe that he has written application notes for Analog devices. His web site:http://waltjung.org/He was somewhat involved in the old TIM debate, or is at least mentionedby John Curl on DIY Audio when he brings it up.Jung also did this excellent history of OP amps paper:http://www.analog.com/library/analogDialogue/archives/39-05/Web_ChH_final.pdfI noticed prior art involving Deane Jensen's patent for the inductorsused in his 990 OP amp. I'm PB2 here:http://www.diyaudio.com/forums/solid-state/107404-simulation-je-990-op-amp-deane-jensen.html#post1289112'>http://www.diyaudio.com/forums/solid-state/107404-simulation-je-990-op-amp-deane-jensen.html#post1289112I really admired Jensen's work on the JE-990:http://www.diyaudio.com/forums/solid-state/107404-simulation-je-990-op-amp-deane-jensen.html Link to comment Share on other sites More sharing options...
Pete B Posted August 20, 2011 Report Share Posted August 20, 2011 :lol: Funny (to those who know how Henry pronounced his name).Built one new XO today. Thanks Pete for the encouragement and advice. Those new inductors are BIG and HEAVY compared to the weenie ones in there originally. Used Carli capacitors and stuck a bypass cap on the tweeter. Doubt it helps but it couldn't hurt. New Dayton "Audio Grade" resistor.Can't wait to get these finished now! But I'm dividing my time between these and the Pinnacle PN6+ Sally find.KentI'm really curious to hear your opinion of the LA, did you considercomparing one with the crossover upgrade and one without? You'rewelcome to try the BSC circuit if you'd like. They're rather forwardsounding without it and they really "lock in" with it. I would nothesitate to give them some power also, I've run 200W/ch keeping itbelow clipping. You would not want to drive them hard with that muchpower, especially originals without ferro fluid in the tweeter. Link to comment Share on other sites More sharing options...
JKent Posted August 20, 2011 Report Share Posted August 20, 2011 Hi PeteUnfortunately I did not keep a "stock" xo, so I can't compare them. I'm betting those heavy new inductors will affect the sound, but have no idea how. I doubt the Carli caps will have an audible effect, since I've been told they have ESRs closest to the original NPE caps. And yes--I'd like to give the BSC circuit a try.Hope to finish the other speaker soon, then stuff the cabinets with 2.1 pounds of fiberglass (according to Carl) and fire them up. The foam is gone--used it as packing material!Here's a shot of the new and old inductors. Big difference!Kent Link to comment Share on other sites More sharing options...
Pete B Posted August 22, 2011 Report Share Posted August 22, 2011 That inductor is so much bigger because it is air core and requires thicker wire.There are very large differences in iron core inductor saturation (distortion)characteristics. Laminated iron for woofer inductors are usually best but thereare also newer Ferrites that are fairly good. I've not seen any measurementson the old Advent inductor but there is a good chance that there will be animprovement with the air core when pushed hard. I don't expect a large difference.Let me know when you have them finished and are ready for the BSC. Link to comment Share on other sites More sharing options...
JKent Posted August 22, 2011 Report Share Posted August 22, 2011 Laminated iron for woofer inductors are usually best but there are also newer Ferrites that are fairly good. . . .I've not seen any measurements on the old Advent inductor . . . .OK. Now I'm confused (again). Didn't you recommend that specific air core woofer inductor? And.. Didn't YOU measure the old Advent inductors? I must be missing something Kent Link to comment Share on other sites More sharing options...
Carlspeak Posted August 22, 2011 Report Share Posted August 22, 2011 OK. Now I'm confused (again). Didn't you recommend that specific air core woofer inductor? And.. Didn't YOU measure the old Advent inductors? I must be missing something KentThat was me Kent. So, you have me to blame if things don't work out to your liking. I found the voicing with the compliment of coils I used changed a bit to the lower side which, if the same occurs for you, you may not need BSC.I have some WT2 woofer coil measurement scans of the old and new but haven't had the time to post them yet.I just summarized the results in an earlier post #19. Link to comment Share on other sites More sharing options...
JKent Posted August 22, 2011 Report Share Posted August 22, 2011 Hi Carl No "blame". I was referring to Pete's page that shows measurements of the inductors: http://baselaudiolab...VENT_LA_XO.htmland here, http://www.classicsp...?showtopic=4919 in Post #3 he recommended a Dayton Air Core Perfect Lay inductor that seems identical to the Erse: http://www.parts-exp...tnumber=266-360Hence my confusion.Kent Link to comment Share on other sites More sharing options...
Pete B Posted August 23, 2011 Report Share Posted August 23, 2011 I measured the linear inductance value.I did not measure the non-linear distortion characteristics.All iron core inductors saturate at some current level.Usually it is at mid to high current levels, but there aresome with odd non-linear characteristics even small signal.All air core inductors do not saturate at all, they havevirtually no distortion.I did repeatedly say that they would probably only makea difference at high levels above 50W. The air core inductorswill certainly not sound worse, only better. Link to comment Share on other sites More sharing options...
JKent Posted August 23, 2011 Report Share Posted August 23, 2011 I measured the linear inductance value. I did not measure the non-linear distortion characteristics.All iron core inductors saturate at some current level. Usually it is at mid to high current levels, but there are some with odd non-linear characteristics even small signal.All air core inductors do not saturate at all, they have virtually no distortion.I did repeatedly say that they would probably only make a difference at high levels above 50W. The air core inductors will certainly not sound worse, only better.Here's one of the things that confused me: I understand that "air core inductors...have virtually no distortion" but earlier you wrote " Laminated iron for woofer inductors are usually best but there are also newer Ferrites that are fairly good" (Post #39). So my confusion involves which is "best" for woofers--air core or laminated iron.Thanks for all the guidanceKent Link to comment Share on other sites More sharing options...
Doug G. Posted August 23, 2011 Report Share Posted August 23, 2011 I think Pete meant, of the iron core inductors, laminated is best.Not of all inductors.So, air core would still be better.Doug Link to comment Share on other sites More sharing options...
Pete B Posted August 23, 2011 Report Share Posted August 23, 2011 I think Pete meant, of the iron core inductors, laminated is best.Not of all inductors.So, air core would still be better.DougRight, there is no question about air core, they are best.Properly designed laminated steel have been considered bestin woofer applications for many years. From memory, I seemto remember the OLA woofer inductor being a Ferrite type, not laminated steel. Their was a test of inductor distortion inSpeaker Builder or AA many years ago and most cored types didnot do well.Erse, for example has some huge cored inductors rated for 500Wthat do not look to be laminated that they claim are low distortion.I'd like to see some independent tests of them.I stick to all air core whenever possible in my best designs. Link to comment Share on other sites More sharing options...
JKent Posted August 23, 2011 Report Share Posted August 23, 2011 I think Pete meant, of the iron core inductors, laminated is best. Not of all inductors. So, air core would still be better.DougOh. Duh That clears it upKent Link to comment Share on other sites More sharing options...
dynaco_dan Posted August 23, 2011 Report Share Posted August 23, 2011 :lol: Funny (to those who know how Henry pronounced his name).Built one new XO today. Thanks Pete for the encouragement and advice. Those new inductors are BIG and HEAVY compared to the weenie ones in there originally. Used Carli capacitors and stuck a bypass cap on the tweeter. Doubt it helps but it couldn't hurt. New Dayton "Audio Grade" resistor.Can't wait to get these finished now! But I'm dividing my time between these and the Pinnacle PN6+ Sally find.KentHi KentWhere did this type of cabinet bracing originate?I've seen the original AR-1W prototype with it's front baffle radial bridging and the usual AR-3 and 3A cabinet with it's horizontal bracing but never front baffleboard to back panel bracing.Is this a new technique for strength? Link to comment Share on other sites More sharing options...
JKent Posted August 23, 2011 Report Share Posted August 23, 2011 Where did this type of cabinet bracing originate? . . . Is this a new technique for strength?Originate? I dunno. I basically copied Carl's technique. See attachment to Post #12:http://www.classicsp...?showtopic=2895Front-to back certainly adds strength, it's easy to do and the screw heads are on the front baffle and back panel so there's no "screwing up" the veneer. Seems to work well. I just added bracing to a small Pinnacle speaker, too.Also check the Human Speakers sitehttp://www.humanspea...wto/bracing.htmHuw Powell writes: "Places where the baffle is cut for the drivers, and hence weakened, are also ideal candidates - since not only is the material weakened by the cutouts, but this is where the "equal and opposite reaction" energy of the drivers enters the cabinet material directly. Often you will find that these two become one and the same - the rear panel is the largest, and putting in front-to-back braces around the woofer, say, will stiffen it nicely. "Kent Link to comment Share on other sites More sharing options...
JKent Posted August 24, 2011 Report Share Posted August 24, 2011 Finished the crossovers, put one speaker together. I used 33oz of fiberglass, consistent with Carl's write-up but although they sound "good" they seem a bit bass heavy compared to the AR91s. Any suggestions?Kent[edit] OOPS. Nevermind. It's not the bass. I have one bad tweeter. Sounds like a tissue paper & comb kazoo Can someone tell me if the offset fried egg tweeters in the OLA were the same as the ones in the Smaller Advent? They look the same but I know the Smaller Advent was a 4 ohm system. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.