Vinyl Asylum

I have no problem with system listings. I simply choose to not list my system. Anyway ...

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Garth

(A)

In Reply to: Re: And what are those? Do you like them? (nt) posted by tketcham on September 8, 2006 at 11:48:32:

if interested I can show you how to change the input impedance of either of those preamps, and both are fine products no need to get rid of them, to any value below 100 ohms without even touching the preamps.
Interested? That's what you really want to do is it not?
Cheers!

Follow Ups:

Yes, indeed. - tketcham 12:16:56 09/08/06 (7)
This is turning into a 20 questions game, but yes basically I'd like to be able to run a sub 100 Ohms load for cartridges that may require or benefit from it.
Now, as for the ability to get "any value below 100 ohms without even touching the preamps" I'm all ears (or eyes as the case may be.)
Tom
PS: This is also seemingly a deja vu discussion. Is there a good link to a concise description of the methodology you're prescribing? Don't get me wrong, customized instructions are vastly superior to generic themes.
- Ok, just wanted to know what you really wanted to do. Here goes .... - Garth 13:18:55 09/08/06 (6)
  First you need a RCA "Y" adaptor which allows two males to plug into one female, IE the current phono input female will now accept two male RCAs.
  One is the phono cable and the other is a RCA plug with a resistor soldered inside to alter the preamps input impedance.
  A sample is pictured above. Thanks to JE for the pic.
  By placing an additional resistor value in parallel with the 100ohm in the preamp input you can lower the input value to anything below 100ohms.
  Here are some common values in parallel with 100ohms:
  100ohms = 50ohm load
  80ohms = 44ohm load
  60ohms = 37ohm load
  50ohms = 33ohm load
  40ohms = 28ohm load
  25ohms = 20ohm load
  10ohms = 9ohm load
  It's that simple and a whole lot cheaper than buying a new preamp just to change the input load.
  Cheers!
  - Thanks, Garth. Now for the $64,000 question(s)... - tketcham 18:37:38 09/08/06 (4)
    Where do I purchase these resistors?
    Specifically which ones do I need?
    
    Are there specific RCA plugs that you recommend?
    
    Can you describe in detail how to solder them into the RCA plugs?
    
    Is there special solder I should use?
    
    Is there a soldering iron that you recommend?
    
    Did you mean (input impedance) that they plug into the phono preamp?
    Will I create a potentially damaging signal if I don't solder the resistor in properly?
    Tom
    - And the 2 bit answer .... - Garth 23:29:38 09/08/06 (3)
      good question!
      If you were in Germany or the UK I would know where to send you but in the USA being such a small country the choices are limited. And with everything being on ration due to the wars it may be hard to find military items like resistors and soldering irons. And "mother's against lead" have made solder nearly impossible to get. Have you considered moving?
      But seriusly your local Radio Shack should have everything you need. Buy the cheapest RCA connector and resistors, 1/4 watt.
      - FYI - mosin 10:25:04 09/09/06 (0)
        
        In Reply to: And the 2 bit answer .... posted by Garth on September 8, 2006 at 23:29:38:
        
        Carbon fiber supplies are getting short, so prices are going up.
      - The nearest Radio Shack is over 160 km away... - tketcham 02:00:16 09/09/06 (1)
        
        In Reply to: And the 2 bit answer .... posted by Garth on September 8, 2006 at 23:29:38:
        
        so I'll be doing my shopping online. Just looked at resistors at the Parts Connexion website and there is a dizzying array of them. (The Vishays look suitably hi-fi.) I ASSume that "value" is the Ohm rating of the resistor, right?
        Do the resistors have directionality or polarity; ie, is there a specific resistor lead that goes to the outside of the plug and one to the inside? Damn, my electronic ignorance is showing. Now you can see why it would be easier for me to just buy a Phenomena.'-)
        And would this work well for soldering?: supermax soldering device
        I'll just have to make do with the limited availability of parts and equipment in the U.S. as you have so cleverly deducted. Our country is on the brink of Marshall Law to ensure order in this time of chaos. The panic has only begun to surface. Why only yesterday there was a run on iPods and Apple had to make a hurried nationally televised/streaming video announcement (and XM and Sirius satellite radio simulcast) pleading for people to keep calm, that they will do everything in their power to meet the demand.
        Most defectors and lead solder lovers are heading to Canada, the unassuming yet lovable sibling runt of the U.S., although the Federal Republic of Germany is much more accomodating, greeting each and every U.S. citizen with open arms and a free stein of last year's overstock of Octoberfest ale.
        Tom
        
        Oh man, Omak! - Garth 02:34:25 09/09/06 (0)
        
        In Reply to: The nearest Radio Shack is over 160 km away... posted by tketcham on September 9, 2006 at 02:00:16:
        
        Don't buy "boutique" resistors. Just plain cheap and dirty 1/4 watt 5% carbon film. They are not polarized.
        Keep your head down! :-)
        Make sure you get a license to operate that soldering iron!
        Like they say in Omak, Have a nice weekend!
  - Thanks Garth, I also really wanted to just try on my Rogue nt./ - valvesonly 16:58:50 09/08/06 (0)
    ny

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