Shorting Plugs - Stereomour

M42 · 2375

0 Members and 1 Guest are viewing this topic.

Offline M42

  • Full Member
  • ***
    • Posts: 114
on: January 24, 2014, 03:17:42 PM
Hi all,

I have made a couple of shorting plugs as per the advice here on the forum. I used 5.1k ohm 2% resistors. Am I correct in my understanding that the shorting plugs will be put in one set of inputs only? I presume there is no need to make the adjustments at all three inputs. In other words, pick one pair of input jacks, short them both out with the plugs and measure as per the instructions in the manual. I've attached a photo of my plugs. I understand if I  assemble or use  these incorrectly I can cause serious damage to my amp! Looking for confirmation I have things right.

Many thanks,

Jeff


Jeff Hullin

Stereomour(2A3), Eros, Crack/Speedball, Thorens TD160 MKII, Grace F9E, Sennheiser HD600's, Frugelhorn 3's, DIY 8" Subs.

If at first, the idea is not absurd, then there is no hope for it.


Offline Mike B

  • Full Member
  • ***
    • Posts: 248
Reply #1 on: January 24, 2014, 05:12:03 PM
I only made 1 shorting plug and it was a direct (wire) short.

You can only adjust 1 pot at a time, so why make 2?

Far away from the bleeding edge


Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #2 on: January 25, 2014, 01:37:30 AM
Jeff,

Exactly, only one set of inputs.

Mike,

Because you buy them in pairs.  You can also use them as a load for breaking in cables.
« Last Edit: March 31, 2014, 03:47:03 AM by Grainger49 »



Offline M42

  • Full Member
  • ***
    • Posts: 114
Reply #3 on: January 25, 2014, 04:48:13 AM
Mike/Granger,

Thanks for the information, it's much appreciated. I was under the impression that both the right and left channels of any given pair of outputs had to be shorted to trim the pots. Now I can move forward. Thanks again

Jeff Hullin

Stereomour(2A3), Eros, Crack/Speedball, Thorens TD160 MKII, Grace F9E, Sennheiser HD600's, Frugelhorn 3's, DIY 8" Subs.

If at first, the idea is not absurd, then there is no hope for it.


Offline M42

  • Full Member
  • ***
    • Posts: 114
Reply #4 on: January 25, 2014, 07:59:45 AM
Hi,

I have adjusted the hum pots,but I think I'm seeing some rather implausible numbers. With the meter auto-ranging on ac volts...I am trimming both pots to a reading of .001 mV? The manual states the values should fall somewhere between .08 and 2.0 mV. Any thoughts?

Jeff

Jeff Hullin

Stereomour(2A3), Eros, Crack/Speedball, Thorens TD160 MKII, Grace F9E, Sennheiser HD600's, Frugelhorn 3's, DIY 8" Subs.

If at first, the idea is not absurd, then there is no hope for it.


Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19757
Reply #5 on: January 25, 2014, 08:02:59 AM
0.001V is 1mV, which may be what your meter is showing.


Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline M42

  • Full Member
  • ***
    • Posts: 114
Reply #6 on: January 25, 2014, 08:09:25 AM
Thanks Paul...looks like the amp's adjusted right down the middle. I think I'll I'll leave well enough alone...at least until I learn to read a meter!

Jeff Hullin

Stereomour(2A3), Eros, Crack/Speedball, Thorens TD160 MKII, Grace F9E, Sennheiser HD600's, Frugelhorn 3's, DIY 8" Subs.

If at first, the idea is not absurd, then there is no hope for it.


Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #7 on: January 25, 2014, 08:16:40 AM
Those numbers are probably as low as your meter goes.  I'm not sure mine goes any lower on AC.

Keep the pots there and listen to some music.
« Last Edit: March 31, 2014, 03:44:17 AM by Grainger49 »



Offline M42

  • Full Member
  • ***
    • Posts: 114
Reply #8 on: January 25, 2014, 08:27:03 AM
Hi Granger...thanks, I'm going to do just that. I have my NST speakers set up for (desktop) near field listening. With barely a dozen hours on the amp it already sounds amazing. I can't wait to hear it with one hundred hours or so on it.

Jeff Hullin

Stereomour(2A3), Eros, Crack/Speedball, Thorens TD160 MKII, Grace F9E, Sennheiser HD600's, Frugelhorn 3's, DIY 8" Subs.

If at first, the idea is not absurd, then there is no hope for it.