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Fleabay impulse buy....

Very dangerous when you are half asleep late at night after a very stressful day at work and the eBay app on your phone buzzes, auction about to end. Your mind goes into fight mode adrenaline pumping, all dorwsiness disappers, and you are hyper sensitive, you body mind and soul channelling all it's energy into the tip of your fingers and you very tensely concentrate on.... Click... Wait, what, who, where ...
 What did just happen.... The buzzes again, with a congratulatory message, apparently I am the winner of.....

Comments

  • This pair of yellow things....

    4thtry
  • and This Is How they measure...

    a bit off from each other, but they will be active, so hopefully, should not be too much trouble


  • Ooooo, those are beautiful! 
  • Craig K would be lovin those!
  • This kind of thing happens - last time it happened to me I woke up and realized I had spent $100 on vintage USSR resistors (among a few other odds and ends) a few weeks ago. Whoops. Neat resistors, though:


    Ceramic insert with an aluminum over-wrap. I bought 18 in the 27 ohm value and 16 in the 1 ohm value. I have a problem with buying resistors, I tallied up the last two months and I am about $250 into this buying spree for vintage wire wound resistors. Guess sandcast just lost their appeal. Most of ones I have bought are NOS Dale with a smattering of Soviet and other stuff. The old Dale resistors have what looks like 16awg or better leads, though, worth the price of admission over the the shit tinsel crap on modern sand cast stuff. 

    kennyk4thtry
    I have a signature.
  • Ooops, realized the measurement attachment did make it. So here it is again.
  • Ok, the attachment thingie is not working. It shows the file in the message, but after posting it doesn't show up - it's a PDF file - i'll ping Jason. I'll try taking a screenshot and posting:



  • One thing I have been looking at lately is the breakup wrinkle in the impedance curve. I have decided if they overlay pretty tight between two or more samples, it is evidence of good quality control in soft part assembly. I see a striking disparity between these two drivers in that regards. Good thing they are not meant for use as anything but a woofer. Should be very good in that regards. 
    I have a signature.
  • jr@mac said:
    This kind of thing happens - last time it happened to me I woke up and realized I had spent $100 on vintage USSR resistors (among a few other odds and ends) a few weeks ago. Whoops. Neat resistors, though:


    Ceramic insert with an aluminum over-wrap. I bought 18 in the 27 ohm value and 16 in the 1 ohm value. I have a problem with buying resistors, I tallied up the last two months and I am about $250 into this buying spree for vintage wire wound resistors. Guess sandcast just lost their appeal. Most of ones I have bought are NOS Dale with a smattering of Soviet and other stuff. The old Dale resistors have what looks like 16awg or better leads, though, worth the price of admission over the the shit tinsel crap on modern sand cast stuff. 

    I am pretty ignorant about resistors. though the Mills wire wound resistors are expensive compared to the Dayton sandcast audio grade ones. Should i be hunting down the vintage wirewound resistors? I have pretty big stock of the dayton audio ones though. Are wirewounds better than the sand cast ones - in what way - tolerance or there is some other audio magic going on like caps?
  • jr@mac said:
    One thing I have been looking at lately is the breakup wrinkle in the impedance curve. I have decided if they overlay pretty tight between two or more samples, it is evidence of good quality control in soft part assembly. I see a striking disparity between these two drivers in that regards. Good thing they are not meant for use as anything but a woofer. Should be very good in that regards. 
    the impedance breakup is around 1k / 1.1k, I won't be going over 100hz for these. 4 way, 40-100 vented with these, 8" woofer sealed 100-300, 5" mid 300-3000, AMT 3k+, all active.... but this is project is a way off, maybe next year..... have a few in works for this year and I HAVE to enjoy the summer..... family time!
  • ani_101 said:
    jr@mac said:
    This kind of thing happens - last time it happened to me I woke up and realized I had spent $100 on vintage USSR resistors (among a few other odds and ends) a few weeks ago. Whoops. Neat resistors, though:


    Ceramic insert with an aluminum over-wrap. I bought 18 in the 27 ohm value and 16 in the 1 ohm value. I have a problem with buying resistors, I tallied up the last two months and I am about $250 into this buying spree for vintage wire wound resistors. Guess sandcast just lost their appeal. Most of ones I have bought are NOS Dale with a smattering of Soviet and other stuff. The old Dale resistors have what looks like 16awg or better leads, though, worth the price of admission over the the shit tinsel crap on modern sand cast stuff. 

    I am pretty ignorant about resistors. though the Mills wire wound resistors are expensive compared to the Dayton sandcast audio grade ones. Should i be hunting down the vintage wirewound resistors? I have pretty big stock of the dayton audio ones though. Are wirewounds better than the sand cast ones - in what way - tolerance or there is some other audio magic going on like caps?
    Short of opening a can of worms, not all wirewounds are created equal. The so-called audio grade are usually double-wound in some way, inductance is lowered in this manner. Think of the windings looking like this from the side: XXXX

    Cheaper wire wounds are generally single wrapped, look like this from the side: \\\\

    Then there are those who issue the challenge of "prove to me the inductance of a 4 ohm wire wound matters" as it may actually be on the order of 0.001 or 0.002mH.

    Me? I just prefer the looks of this type of resistor:


    That happens to be a 100ohm Dale, not sure of any other actual details other than when they arrived here they were mounted on a bigass cardboard backer that looked about 40 years old. 

    No idea the general construction, either. Either enamel or silicone coated. 

    That is pretty much all I know about them. Oh, and the thermal ratings can be deceiving. For example, the fancy heat-sinked resistors are small form factor for a given wattage - however if they are not mounted to a chunk of heat conductive material to serve as an additional heat sink, their power handling is generally derated quite a bit. 

    So, no commentary from me on resistors other than some general background on construction methods - I buy on looks. 

    4thtry
    I have a signature.
  • ani_101 said:
    jr@mac said:
    One thing I have been looking at lately is the breakup wrinkle in the impedance curve. I have decided if they overlay pretty tight between two or more samples, it is evidence of good quality control in soft part assembly. I see a striking disparity between these two drivers in that regards. Good thing they are not meant for use as anything but a woofer. Should be very good in that regards. 
    the impedance breakup is around 1k / 1.1k, I won't be going over 100hz for these. 4 way, 40-100 vented with these, 8" woofer sealed 100-300, 5" mid 300-3000, AMT 3k+, all active.... but this is project is a way off, maybe next year..... have a few in works for this year and I HAVE to enjoy the summer..... family time!
    That will be a great build! Yep, no worries on the disparity then - if you look closely where it matters for the anticipated bandwidth the two drivers are virtually identical.
    4thtry
    I have a signature.
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