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Scott Grammer

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Everything posted by Scott Grammer

  1. Hello, all. I need suggestions about how to properly (so as not to do any damage) and thoroughly clean records made materials other than vinyl, such as 78's, one-off records made on old home or pro record lathes, certain transcription discs, etc. I want maximum cleaning as well as preservation of the disc. Any help would be appreciated. Thanks! Scott.
  2. Hi. I work on vintage audio gear for a living, so I thought I'd try to give you a little more solid answers to your questions. As for the bulb going out, most likely it just burned out. There is a fuse for that lamp, however, but I doubt you'll find it blown. It's marked "Fm3" on the circuit board. You'll find three fuses on the main circuit board, two parallel to each other and one at a right angle to them. That one at a right angle is the fuse you're interested in. It's a 500mA (or 1/2 amp) fast-blow fuse. As for the meters not working, there's nothing in common between the lamp and the meters, and the meters are literally powered by the signal going to your speakers, so I'm at a loss as to why they would not work if the amp is playing. There are a pair of 47 microfarad capacitors in the meter circuits that, if they have become leaky enough, could cause the meters to stop working, but it seems unlikely. It may just be that you don't use enough amplifier power at your normal listening levels to make the meters swing. And that amp should be more than powerful enough for such sensitive speakers, unless you have a really large listening room and like to listen really, really loud. Still, if the amp has never been serviced, now would be a good time to take it to someone experienced with vintage audio gear and let them give it a check-up. And if you decide to check on that fuse, PLEASE unplug the unit from the AC power first. Scott.
  3. I'll look it up. Thanks. Edit: I looked it up. That's an awful lot of bucks. Must be a lot of bang to go with them. Scott.
  4. Hey, folks, I am looking for a long (12" or longer) tonearm, preferably with an SME headshell socket, to play 16" records. Alternatively, a turntable already outfitted for such use would be great. I'm not loaded with money, but on the other hand it does not have to be pretty or even working. Please PM me if you have something like this. Thanks, Scott.
  5. Stanford Research Systems SR770 FFT Network Analyzer for sale, CHEAP! Works, but needs internal battery replaced. It's on eBay, so you can look it over there, and if you like you can PM me here with questions. Please do not ask questions about price here! Save that for PM's, please. https://www.ebay.com/itm/176115317547 Scott.
  6. If you are building your own tube amp (or if you want to keep track of hours on a stylus), you may be interested in this. These are 12V powered, non-resettable hour counters made by Motorola, NOS in boxes, unused. I have ten of them. Here's the link. If you have questions, you can PM me here (NOT IN THE THREAD, PLEASE), or through fleabay. https://www.ebay.com/itm/175950574058
  7. Yes, I've been keeping an eye on those. I'm gathering all the service lit on the different models and I'm not sure exactly which one I want, but typically, a manufacturer's first try is the best, or one of the best, and later iterations are changes to keep the beancounters happy. Except, of course, when the changes are for stability or to cure issues not known until the amps were in the field. Scott.
  8. I'd like that. And maybe I can figure out what changed. The current limiting no doubt saved the amp, but things surely got hot in the process, and so values might have changed, or outputs may have been weakened. Next time you're coming my way, holler at me and we'll set a time for me to meet you at the shop. Thanks, Scott.
  9. Thanks. I'll find and download a service manual if I end up with the one I'm looking at. The owner and I are working on a trade.
  10. I'm negotiating with the guy regarding price, and I think I'll probably end up with it.
  11. Thanks. That's exactly what I was wondering about, noise with efficient speakers and of course sound quality compared to more upscale hi-fi amps. Oddly, I don't think I've ever repaired a D-75. I suspect, considering how many were sold, that this is because they don't break down; a big plus in my book.
  12. I'll dig that up. I've seen the D-45 and the D-60. The 75 is the only one I've ever actually used, as a headphone amp in a studio years ago. Edit: I found a pdf of the thread through the link you provided, and it appears that much of the work done to create "The Duke" was recapping with better caps. This is certainly part of what I would want to do. There was also replacement of opamps for more slew rate, but as my hearing tops out at 13k anymore, I don't know if that would ever be audible to me. The caps will certainly be up for replacement, though.
  13. I have an opportunity to buy a Crown D-75 for a very reasonable price. It's clean, never been racked, but of course it's old, and probably needs a bit of freshening up. What do you think of the sound, especially with efficient speakers? Thanks in advance for your thoughts.
  14. A client will be bringing me a Cary SLI-80 soon, the older version from the 90's, not the newer HS version. I spoke to Cary about getting service info, and they said, and I quote, "Proprietary to the company." If anyone has a schematic, it might well be useful. Feel free to PM me. Thanks in advance.
  15. I didn't think I remembered seeing them. I know that later LaScala's were made from thicker material, but for the clones I built, which were 3/4 inch marine-grade, void-free plywood, the braces helped. Of course, I imagine my construction techniques were not as good as the originals. Had they been, maybe the braces would not have been needed.
  16. I notice the horizontal braces in the mouth of the bass horn, to shore up the side panels. Almost 40 years ago, when I built clones of the LaScala bass cabs for use in a PA system, I noticed right away that these were needed. Adding them made a tremendous difference, and I think those in the picture are twice as thick as the ones I added.
  17. Here are the pictures: https://postimg.cc/gallery/qMpr4KP
  18. I'd be happy to do that, but I did say first come, first served, and so I will send the pics to the other member first. If he is not interested, then I will post the pics here.
  19. I'll shoot the pics tomorrow (Monday) and send them. Scott.
  20. Real ones, not knockoffs. No drivers, just the horns. If interested, please contact me privately. It will be about a week before I know if I will be selling them. First come, first served. Thanks.
  21. I'm guessing you lost a tweeter diaphragm. Playing too loudly with too small an amp is a guaranteed way to make that happen with any speaker. Disconnect the tweeter from the speaker system, and use an ohm meter to measure its resistance. It should be 6-8 ohms. If it's way off, either way too low (less than say, 4 ohms) or way too high (more than say, 12 ohms), it will need to be replaced. Have a pro replace the diaphragm with the real deal, not a knockoff. Cheap replacement diaphragms sound like crap as a rule, and they often don't last long. Some won't even fit.
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