Potentiometer [message #30162] |
Thu, 20 January 2005 17:44 ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
colinhester
Messages: 1349 Registered: May 2009 Location: NE Arkansas
|
Illuminati (3rd Degree) |
|
|
Well, let's the dumbass questions begin ![](http://www.audioroundtable.com/emoticons/smiley.gif) Why is the potentiometer 100k? Let's say I wanted to use the Sweetest Whispers stepped attenuator kit from Bottlehead; it's rated at 15k. What issues would I run into trying to use this in our preamp? Can the Sweet Whispers or the preamp's circuit be modified to make this work properly? In reality I'll more than likely go with Alps Blue Velvet. Is this a good choice? .....Colin
|
|
|
Re: Potentiometer [message #30166 is a reply to message #30162] |
Thu, 20 January 2005 18:38 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
PakProtector
Messages: 935 Registered: May 2009
|
Illuminati (2nd Degree) |
|
|
The 100k is just an easy grap from the RadioShack parts bin. It is not a bad sounding pot, and offers a light load to the source. The E-T Sweet Whispes is a fine sub. As is the ALps Blue. Pick what ever you and your source are comfortable with. There are as many options for this as there are flavours of coupling cap. regards, Douglas
|
|
|
Re: Potentiometer [message #30174 is a reply to message #30162] |
Thu, 20 January 2005 22:22 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) |
![](http://audioroundtable.com/forum/images/custom_avatars/5.gif) |
Wayne Parham
Messages: 18752 Registered: January 2001
|
Illuminati (33rd Degree) |
|
|
You can make a stepped attenuator using any values you like. It's a pretty easy thing in principle, just a lot of resistor pairs to form voltage dividers with precise ratios where both resistors of the pair add up to the same value. It makes a precise divider but switch contacts sometimes click as they go open for an instant before closing on the next resistor pair, or vice-versa. By the way, I've put an OrCad schematic file online. If everyone would rather standardize on a different platform, I'd be happy to upload alternate file types. The nice thing about OrCad is that it has the option of laying out circuit boards and running PSpice analysis. We'll probably not have boards etched, but we may use Spice for some what-if analysis at some point in the future. And having a format for distributon of schematic drawings that allows easy modification of the schematics is nice too.
|
|
|