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Everything posted by dynaco_dan

  1. 1File.pdf Hi there PART 1 of 5 I will be scanning and posting my collection of AR literature here over a period of a few days or so. Standby. This is the AR-LST blueprint photocopied in manageable sizes plus a few other repeats. This is my photocopies of an original AR blueprint. If I was to have the blueprint on a cd or dvd I can get it printed as long as it is less than 54" in one direction. It can be as long as one would want though. It would be $4.50 per square foot just to print. We have lost some good copy companies here in the last few years. I would need to search out a company here that can scan such a large drawing and it would not be cheap either. You will need to jigsaw the sheets together yourself. If I have downloaded any from this site, Mark or Gene can delete them. I scanned in 200 dpi which is my new scanners default, but it can be incresed slightly to 300 dpi. I used a post-it-note with a number which is not in page order or document order, just tried to keep them identified only. None are over 600KB in size. Enjoy. 2File2.pdf 3File.pdf 4File4.pdf 5File6.pdf 6File.pdf 7File8.pdf 8File10.pdf 9File.pdf 10File14.pdf 11File16.pdf 12File18.pdf 13File20.pdf 14File22.pdf 15File24.pdf 16File26.pdf 17File28.pdf 18File.pdf 19File2.pdf 20File34.pdf 21File36.pdf
  2. dynaco_dan

    Repair abvice BIC 8950 8” Woofer

    Hi there Try solder-wick, available in several small gauges. It may be what the manufacturers used in the old days. Vern
  3. dynaco_dan

    Cloth surrounds

    Hi there; I was day-dreaming, again, about all the write-ups regarding the, KLH butyl speaker surround coating of their many speaker surrounds. It appears that in a KLH service bulletin, that the warantee depot would apply an additional coating of the KLH supplied butyl material. I believe that Kent mentioned recently in the KLH forum that a particualr manufacturer does not make it anymore. Other than, Tom Tyson's, please correct me if I am wrong, suggestion to use ArmorAll to rejuvinate AR cloth surrounds, 2 coats 24 hours apart, there seems to be no other information. At least at this time, there is no mention of the solution that AR used or any follow-up coatings. Surely there must be a source for liquid butyl, today, I do not mean only in 45 gallon drums either. Aleenes watered down glue has been brought up, water downed latex sealant, as well as a liquid compound by a mailorder speaker repair company. I have been looking at a pair of early used AR-2AX speakers that I bought this past year. They both have the old aluminum frame, alnico magnet woofer with cloth surrounds. The woofers both have a set of 4, hand applied x's, of a liquid compound, as well as a smear of it on the dust domes. The X's are not uniform in size or shape but definitely hand painted on the cone material. I assume this is to add weight to the cone and cutdown on cone-cry. Has anyone here used ArmorAll and can say that this is a suitable substitute for the factory original material. Is two coatings enough, or should we use more? It is strange that when these speakers were produced, in the 1960's, there has been no mention of a sealant for the surrounds ever since.
  4. dynaco_dan

    Dynaco amp mods and tweeks

    I have a few mods or tweeks information on Dynaco's ST-150, ST-400, ST-410, ST-416 amps also series 80 amps and ST-120. If there is sufficient interest I will follow up here in the near future. If I remember correctly there was a phase 2 Dynaco ST-400, I have no information on why there was this added model designation. It may have been an internal doc. Please post here if you are interested in following up on these issues. Remember there is a serious risk of shock if you are not experienced. There was a TIP mod well known for the ST-120 but there was also a similar TIP mod for the 80 series. The mod for the ST150 - ST-416 amps is on Greg Dunn's web site. It was posted there around 2002. You can print out the article. A set of 8 pages has been deleted there that would have created a 600 watt mono amplifier. No explanation posted. Perhaps liability issue. Vern I do not have an email address yet.
  5. dynaco_dan

    Dynaco amp mods and tweeks

    Hi there Just recently I came across more old paperwork. The TIP mod for the ST-120 amp is an 8 pages instruction and parts list. Gregg Dunn site has that TIP mod with a short list of parts with no instructions, which is all that he may have been given. My comment is not negative for Gregg's site which is very beautifully done, but without a forum. Also another 8 page mod to increase the ST-400 to a ST-416 watt amplifier output, referred to as "The Double Dyna", substantially doubling a ST-400's wattage output. Stereo Cost Cutters (SCC) Dec 1983 catalog of most of 13 pages of 24 pages 8 1/2 x 11 paper size remaining Dynaco inventory they had purchased on Dyna's closing, 40,000 pounds worth. The parts list of only 5 pages was done in such a small font, it may not even be scanable. US and Canadian Dynaco wholesale and retail price lists. The MBI-400 mod changes around parts, wires, etc to turn a 400, 410 and 416 into a 600 watt mono amps and this is to be considered non-reversible and very prone to hurt the user (hernia). This project is extensive and the possibility of expensive damage to the amp, if an error is made or serious personal injury, also 8 pages long, not for the rookie. The danger is so great that maybe that is why it was pulled from Greg Dunn's site. I will scan and post some as soon as I can. Errata: There was 60,000 pounds of parts and inventory. There is also 2 follow-up SCC hot sheets which mentions that they had a flyer, 20 pages, of just Dynaco. I'm only mentioning that fact, I don't have it, date unknown. Vern
  6. dynaco_dan

    AR-XA in box?

    Hi there This is the earliest 2 speed motor set. There doesn't appear to be the platter drive belt in the photo, oh well, less than $5.00. Vern
  7. Hi there I just read this topic a few weeks ago, thank you very much. Most all Audio magazines are complete and in downloadable condition, from 1950 - 1990+, thanks to the website owner. I could only imagine if they were presently being newly sold including coupons on every other page, lot's of missing sections. LOL Edgar Villchur was a very knowledgeable contributing author prior to AR. Vern
  8. Hi there I thought I would jump in here. I have both speaker systems, AR-3A's first and LST's later. When the opportunity to demo a pair of LST's in my house came up in the mid '70's, I jumped at it. I had the 3A's for several years of ownership and almost constant usage, so I had in intimate opinion of their capabilities. To add another point here is that I also had a Crown DC-300A amp and IC-150 preamp on another weekend loaner and after only a few minutes of listening again, the 3A's were outstanding reproducers on their own. In this case the electronics made all the difference, and they also were returned. My feeling after only a few minutes of usage with an AR amp was that the LST's were at least double the 3A's or at least considerably better. This was a weekend test setup and I returned them after the weekend, no WAF. I am sure I pouted for many, many weeks until in the mid 1990's when I bought a used and abused pair of LST's. Still not having the money or brains to turn down yet another used pair, I bought another used pair a few years later. No, I haven't stacked them, or placed Microstatic array tweeters on top of them. If you keep your eyes open, try to find an original pair of LST's as mint as possible. In my opinion, if you were to build your own cabinets, and be given brand new drivers and use the AR-3A crossover you would likely be happy with them, even with them being audibly less than real LST's. The LST's are great reproducers but they are only speakers. Vern
  9. dynaco_dan

    Newly acquired AR-LST

    Hi there I would suggest using small brass double nuts, bolts and lock washers, rather than those steel ones. If you have a source for FNM fuses I would suggest a 1 1/2 amp rating maximum rather than 2 amp. Great speakers with top end electronics. That stool looks just the right height and strength to use as a speaker stand, just not as pretty as a dedicated stand. Sure would be a lot less expensive though. Vern Hi Frank
  10. dynaco_dan

    Newly acquired AR-LST

    Hi there You mentioned the fuse clips. On a pair of LST's I found that AR had soldered them to the circuit board, rather they heated up the clips which made them fragile later on. I had extra regular fuseholders and drilled the rivet off of those clips and used very small brass hardware to remount to the circuit board. I did not solder any of the new mounting so that the clips should not break off in the future from being over heated. Just a thought for today, unless you can find just the original bare FNM fuse clips somewhere. Just do not attempt to solder them to the board. Vern
  11. dynaco_dan

    Dynaco amp mods and tweeks

    Hi again Here I am with some more trivia about the Dynaco 400, 410 and 416 amps. Today I found an article which I will write about another day and perhaps scan and post here. It is a more detailed story about the coil/resistor which I discussed earlier. The colours were correct but they used a black plastic sleeve over the coil. I also came across a copy of the MBI-400 super-charge mod which can increase the mono output to 600 watts This is one of several links that has disappeared from, home.indy.net/~gregdunn/dynaco/components. That site does not have a forum, sadly, because Gregg has done a beautiful job setting it up. Also I came across price lists both retail and wholesale which I need to scan first. To change the subject here, I see lot's of viewers but only a few get involved with this site. If everyone visiting could post an answer or a question it would be great, even if no one here can answer it. Especially me. Also if everyone could post a photo of an article or ad they have of old Dynaco. Vern
  12. dynaco_dan

    Dynaco A-50 cabinet salvage

    Hi there Here is a used pair of Dynaco A-50's I bought from a 2nd hand store for $100.00. Painted black cabinets with over spray on the back and cloths, Yuch. Here is a few photos of the in progressive stripping job and the hidden beautiful walnut veneer. With careful paint stripping and patience you can salvage a very nice quality walnut finish underneath. I used no sandpaper. You can see the mounting plate for wall mounting these floor mounted speakers. Huh? You can also see the standard 8 ohm Seas dome tweeter and the non-standard Seas 16 ohm round frame woofer, not horned. The switch has the non-standard screwdriver switch, not knobbed. The velcroed frame with it's minimal wooden frame supports the neutral flecked beige linen grille cloth more than adequately.
  13. dynaco_dan

    Dynaco amp mods and tweeks

  14. dynaco_dan

    Dynaco amp mods and tweeks

  15. dynaco_dan

    Dynaco A-50 cabinet salvage

    Hi Martin I feel that those tiny felt pads are definitely not enough to really isolate them from the wall. You would need to locate them at least with the tweeter at head height and equally spread along the wall. It is worth a try at least with maybe a piece of carpet between the cabinet and wall. Please report back here with your comments.
  16. dynaco_dan

    Dynaco amp mods and tweeks

    Hi Joel Yes the original composition resistors were slightly under-rated and that chap, Kevin, takes us through the steps to get to and replace them. After completing those replacements we get a helping hand to reset the bias. Only listed tools, parts and a VOM are needed. Which caps did you replace and were the new ones 85' or 105'? Did you strip the amp right down to it's basic components? Great job for someone here to do, you must be highly skilled. I picked up a Dyna 400 with meters here because one channel was dead. It is really ugly as it was tinkered with and likely stored in a damp carport. Less than $50.00 though, another of my rescues. I went to the directory here and see over 80 viewers have seen some or all of this topic. I wish some of those viewers would leave a comment or? Nice to see this amount of interest in this topic.
  17. dynaco_dan

    Dynaco A-50 cabinet salvage

    Here it is a little late, sorry. It is now 210kb in size rather than the several mb of the original photos. Vern Dynaco A-50.pdf This photo was the most interesting one of all the ones I took. The underlying walnut veneer is beautiful and it was worth all the effort to remove the paint. My comment earlier was because Dynaco was not going to be using the metal corner hanging bracket plates on the A-50's at least. You would need to really isolate the back of the enclosures from the wall or the wall would now become part of that enclosure thereby over exaggerating the bass. Yes, you can place rubber or felt pads on the rear of the cabinet.
  18. dynaco_dan

    Dynacos stuffing replacement!

    Hi there Here is my 2 cents worth of advice for this evening. With the classic Dynaco A-25's etc unless the cap is defective, such as is open, leave it alone. Some folks replace the caps with new ones and are happy. With the resistors unless you see one or more cracked or burnt up, which I've never seen, leave alone as well. Some folks replace the resistors and are happy. The cabinets fiberglass insulation was particularly fine material and without question should be left intact. There is much synthetic material which might do as good a job but without test equipment you will likely end up with less than you started with. The vent opening was covered with a particular piece of fiberglass which was determined by lab equipment. The switches were of good quality and very reliable. Wire was adequate for the job. Overall the Dynaco A-25 and family are well designed at a dollar compromise. No foam rot is a big plus issue. When a replacement driver is needed there was so many sold that there is a flood of used OEM drivers available. Vern
  19. dynaco_dan

    Dynaco amp mods and tweeks

    Hi Joel The site referral is a site without an active forum. The repair was written by Kevin Boales for PC-28 circuit boards. I can print out the St-400, etc, mod for my use but I do not know how to just save it. This mod is for usually one dead channel and it covers replacing a common cause of the one dead channel. I do not feel it is ok for me to print out that file and re-scan it and post it here.
  20. dynaco_dan

    Dynaco A-45 speaker system

    Hi there; I was watching the pair of oil walnut Dynaco A-45 speakers on ebay, until it ended a few minutes ago. Sniping drove the price from under $60.00 to $203.50 in the last minute. This same speaker model was also listed a few months ago, a rariety. I've downloaded a few of the photos that were used in that auction. Notice the mis-matched woofers, this should bring up some discussion here. I wouldn't mind listening to them. Vern
  21. dynaco_dan

    Should the AR-5 have been a 12" Speaker?

    Hi Frank It appears that you have all of the toy's and all in one room my friend. Vern
  22. Hi there Thank you for posting this information here. Vern
  23. dynaco_dan

    AR Turntable Documents

    Hi there Thank you for posting this information here. Vern
  24. dynaco_dan

    AR turntable Trivia 1

    Hi there; It would be interesting to see how many members here have one or more AR turntables, of differing models even, both in storage or in use. AR produced over 350,000 AR turntables during it's lifetime, from 1961 - about 1973. Unless mentioned otherwise, I am referring to the AR-XA specifically here, but it may also refer to other models, such as the, AR-XB as well. The AR-TA, 1962, single speed, was the first one produced, 2 motors, 2 belts, solid walnut base, nickel finished aluminum arm and steel T-beam. The AR-XA 1962 - 1973, 2 speed turntable, was by far the most popular and widely sold model. They used both Philips and Haydon (1159) drive motors, the Haydon was considered the better of the two by AR. You will of course need to remove the masonite base cover (1186) to see which model of motor it has. For some accepted, at least by AR, but clearly unexplained reason, when the power cord is plugged in, but the power switch is off, there is a very slight vibration from the motor. For the AR-XA models, the drive belt (978) stretches and deteriorates in time but a suitable replacement can be purchased from any supplier that stocks tape deck belts. There is only the one size, at least for the AR-XA model, I do not have that length at this time, and they only cost around $5.00 each. The correct size is important, if it is too tight, the bearings will wear and if too loose, there will be belt slippage. A sprinkle of Talc powder on it once a year, will help. If you remove the main platter, use caution, there is a ball bearing (996) which usually sticks to the bottom of the main spindle. This is also true with the tone arm spindle. You can use a light and see if the white flat nylon disk bearing (1092) is still sitting on the bottom of the well. If you have cleaned out the bearing hole and platter shaft, with a lint free cloth, add about 8 - 10 drops of 10 weight motor oil to the well before, re-seating the platter. Be certain not to get any oil on the belt or pullies. I have not read anything to the contrary, DO NOT OIL THE MOTOR. The tonearm has a dampening device, built-in, to slow desent of the tonearm, if it should be dropped. This can be de-activated, if desired. The tonearm pivots on 2 very small conical bearing screws and should be very carefully adjusted to just stop it's floppy side to side wobble. Tighten them too much and the arm will hang-up. The cable and arm total capacitance is 135 pf and if required, make-up capacitors can be added underboard to increase this to match a particular cartridge, for extreme accuracy. If for some reason, you need to add more weight to the headshell, glueing a penny to the underside of the cartridge headshell works best, it is non-magnetic. The only conflict that stands out in my memory was the commentary of hum created or induced by a particular Grado cartridge, an early version only. This may or may not have been using only the AR-TA dual motor version. Other than that, there was always the criticism about the tonearm hanging up, no anti-skating, no cue control and could not track a low as Shure SME or Decca arms. Myself, if I had been asked for feedback, I would have suggested a larger finger hold, it is a lttle too small for my fingers and slightly higher. What the AR turntable did offer was, low cost to the masses, reliable, quiet, simple operation, tonearm included, accessories included, no acoustic feedback and outstandingly fine warantee, including shipping, parts, and labour for 3 years (initally one year). Pretty hard to beat. There have been a number of modifications done to the AR turntables. The Audio Amatuer magazine published a few mods. Merrill does have numerous mods for a price, available. LA Audiophile did a mod or two as well. Stereophile did a mod as well.
  25. dynaco_dan

    Dynaco A-25's & Subwoofer

    Hi there Just a small comment here. The original Dynaco A-25's were very well liked in their day. J. Gordon Holt of the original Stereophile Magazine fame went gaga over them in his first review. Very smooth and wide range, within their limits. I like them very much. Use caution with any bass boost, loudness controls or loud volume levels. You might download Dynacophil's "Dynaco Dynamax" paper from this site. It show's several options for multiple Dynaco speakers of the same brand and model. There is no reason the same cannot be used with most all 8 ohm speakers, at least to experiment with. For more bass, maybe if you have a friend with another pair of A-25's, try paralleling them together. Fusing them with a 3/4 or 1 amp fast blow fuse in an open style fuse-holder will help protect your investment at least. Just a thought. Vern