Mcandmars ramblings \ build thread...

mcandmar · 39240

0 Members and 1 Guest are viewing this topic.

Offline Paul Joppa

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 5751
Reply #105 on: June 11, 2015, 05:45:03 PM
Generally any change that increases resolution (i.e. most of the good ones) will make the next change easier to hear. So the optimal strategy in my mind is to go with the biggest effect first, so that the more questionable "upgrades" get the best chance of making a difference.

Paul Joppa


Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #106 on: June 11, 2015, 05:50:11 PM
Generally any change that increases resolution (i.e. most of the good ones) will make the next change easier to hear. So the optimal strategy in my mind is to go with the biggest effect first, so that the more questionable "upgrades" get the best chance of making a difference.

I think I'll 'fit' the larger mundorf Supremes just to make sure the c4s board won't cause issues and/or how to solve potential issues, then I'll build it stock, add c4s, then solder in the Supremes where I previously fitted them.

Thanks everyone!  Best support community by far.



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #107 on: June 11, 2015, 07:55:25 PM
Has anyone here ever used an Elma attenuator?  Have a line on one populated with kiwame resistors but it's 50k.  Will there be any issues with that?  My source will be a Schiit Modi 2 uber
« Last Edit: June 12, 2015, 12:17:18 AM by ZacharyP »



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #108 on: June 12, 2015, 02:22:11 AM
Elma make the switching part, for example the Goldpoint attenuators use the Elma switches, but add their own PCB's and resistor layouts to make the complete attenuator.  Anything using Elma switches gets a thumbs up from me.

There are different types of attenuator, main ones being series and ladder.  Personally i don't like the idea of series attenuators as you end up with a whole string of resistors in the signal path, where as with ladder style there is only ever two resistors in the path creating a divider. Easy to spot the difference as the ladder style have double the amount of resistors.

Then there are resistor choices, much like brands of coffee or beer everybody will have a preference. Kiwami are carbon resistors, i think they are carbon film as opposed to carbon comp.  Personally i find them a little soft sounding, rounds the edges off and makes things all smooth and cuddly.  Where as metal film i find to be more transparent so you don't notice them.  I've always use Dale RN series resistors in signal paths and attenuators for that reason, but again that's just my opinion, i may be completely wrong about that.

I believe 50k will work fine, especially with something like a Modi driving it as it will have been designed to drive 20k-50k loads.

M.McCandless


Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #109 on: June 12, 2015, 02:26:05 AM
Thanks.  It's an Elma switch populated with thru hole kiwames.  The slight soft sound, or rounding off shouldn't be an issue because I tend towards neutral-bright sound preference.

The attenuator in question:

http://www.diyaudioblog.com/2011/03/elma-stepped-attenuator-populated-with.html?m=1

Thanks again!

Still part of me wonders if the series goldpoint with and resistors for under $180 shipped is the better choice.
« Last Edit: June 12, 2015, 02:28:21 AM by ZacharyP »



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #110 on: June 12, 2015, 02:45:44 AM
Dunno.  Depends on how much you are getting the Kiwami one for.  From what i have read many people dont like the SMD resistor versions of the Goldpoint, i remember Doc B expressing a dislike for them too so stick to through hole resistor attenuators.

Personally i think these are the best value, proper ladder style unlike the current Goldpoints and uses Dale resistors. http://www.ebay.co.uk/itm/assembled-dale-24-step-copper-axis-attenuator-volume-control-100k/281664997434?hash=item41948ac83a 

You can also buy them unassembled if you are a sucker for punishment. BTDT, and swore never again.

M.McCandless


Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #111 on: June 12, 2015, 03:18:14 AM
Ladder attenuators keep a constant impedance to the source.  It approximates a pot with none of the drawbacks of a pot. 

I, personally, would not consider any other configuration.



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #112 on: June 12, 2015, 03:30:38 AM
Dunno.  Depends on how much you are getting the Kiwami one for.  From what i have read many people dont like the SMD resistor versions of the Goldpoint, i remember Doc B expressing a dislike for them too so stick to through hole resistor attenuators.

Personally i think these are the best value, proper ladder style unlike the current Goldpoints and uses Dale resistors. http://www.ebay.co.uk/itm/assembled-dale-24-step-copper-axis-attenuator-volume-control-100k/281664997434?hash=item41948ac83a 

You can also buy them unassembled if you are a sucker for punishment. BTDT, and swore never again.

Biggest issue with that is the ship time can be horrible.  I'd hate to have the kit arrive next week sometime and then I spend a month waiting for the Dale resistor ladder attenuator because I have looked at that one.

Anyone have any extras?  ;)



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #113 on: June 13, 2015, 12:29:53 AM
What is the necessary wattage rating for the 100r heater supply mod?  1/2 watt?



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #114 on: June 13, 2015, 03:18:51 AM
Yes at a minimum as they will be dissipating approx .4watt.

M.McCandless


Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #115 on: June 13, 2015, 03:53:30 AM
Then a one or two watt would be nice to keep the heat down.  heat is an enemy to all components.



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #116 on: June 13, 2015, 06:48:59 AM
Then a one or two watt would be nice to keep the heat down.  heat is an enemy to all components.

My thoughts exactly.



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #117 on: June 30, 2015, 08:50:57 PM
Quote
For those who have installed the c4s, would it be beneficial for me to install the nylon standoff before I populate the terminal strip?  It looks like it'll be a tight fit, removing the nut among the diodes, wires and resistors, and If it saves me from a later hassle then it's worth it.

Thanks for reading!



Offline Grainger49

  • Hero Member
  • *****
    • Posts: 7175
Reply #118 on: June 30, 2015, 11:26:53 PM
It is easier.  You might also get some soldering iron burns on the standoffs while installing components.  Those burns won't compromise the standoff it will just look bad.



Offline ZacharyP

  • Full Member
  • ***
    • Posts: 68
Reply #119 on: July 01, 2015, 05:27:30 AM
It is easier.  You might also get some soldering iron burns on the standoffs while installing components.  Those burns won't compromise the standoff it will just look bad.

Well we don't build amps to stare at standoffs :P

Thank you Grainger!