Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: EarWorm on June 27, 2015, 12:32:54 PM

Title: Shunt or Series Stepped Attenuator.
Post by: EarWorm on June 27, 2015, 12:32:54 PM

I'm leaning towards a stepped attenuator for my crack build but I am not clear if an input impedance issue will be a problem for a Shunt attenuator with the Crack.  So I'm not sure if a Series or Shunt will be better.

Thanks. 

Title: Re: Shunt or Series Stepped Attenuator.
Post by: Paul Birkeland on June 27, 2015, 09:46:05 PM

You'd have to discuss further what specific designs your looking at and what source components you may be using to drive your Crack.

Most stepped attenuators that you see online are ladder attenuators.   

-PB

Title: Re: Shunt or Series Stepped Attenuator.
Post by: EarWorm on June 28, 2015, 06:18:43 AM

My source is a W4S DAC2.   I'm working a slow build toward my crack by upgrading parts over time as I buy the items when they finally appear on sale.  Right now I have a large credit with a vendor and I'd like to obtain the new Khozmos Shunt Attenuator with that credit but I am confused about things I've read about input impedance and shunt attenuators.  Will something like that really matter? 

Eventually I'll design a chassis for all the upgraded components, and I'm not sure of the layout yet but I want to show some things up top the chassis for looks and the Khozmos shunt Attenuator is one of them.  Don't know yet how I would do that but it's too nice looking to hide. But if it won't work as a shunt then I'll do something else. 
I just don't have the experience with the impedance question.   

Title: Re: Shunt or Series Stepped Attenuator.
Post by: JamieMcC on June 28, 2015, 08:45:59 AM

Some pics on headfi of a Khozmo attenuator squeezed into a stock Crack enclosure

https://www.head-fi.org/t/476650/crack-bottlehead-otl/6630

Title: Re: Shunt or Series Stepped Attenuator.
Post by: Paul Birkeland on June 28, 2015, 08:56:19 AM

Quote from: EarWorm on June 28, 2015, 06:18:43 AM

I'd like to obtain the new Khozmos Shunt Attenuator with that credit but I am confused about things I've read about input impedance and shunt attenuators.  Will something like that really matter? 

There isn't really enough data on these to even worry about impedance.  Just go with the 100K specified part.  The input impedance will vary, but your source shouldn't be very stressed driving it.

Title: Re: Shunt or Series Stepped Attenuator.
Post by: EarWorm on June 28, 2015, 09:46:37 AM

Thanks Paul.  I just needed to make sure it wouldn't be a gross mistake since I could find no data about impedance. 

Title: Re: Shunt or Series Stepped Attenuator.
Post by: EarWorm on June 28, 2015, 09:55:08 AM

Quote from: JamieMcC on June 28, 2015, 08:45:59 AM

Some pics on headfi of a Khozmo attenuator squeezed into a stock Crack enclosure

https://www.head-fi.org/t/476650/crack-bottlehead-otl/6630

Jamie, I saw that post when I was scouring the Internet for any info on the
Khozmos.   I think I forfeited the Crack chassis when I purchased these for the power supply.  :)

Warning! Capacitor Porn and choke porn ahead.

Title: Re: Shunt or Series Stepped Attenuator.
Post by: JamieMcC on June 28, 2015, 10:14:12 PM

lol that's going to be a fun build.

Title: Re: Shunt or Series Stepped Attenuator.
Post by: mcandmar on June 29, 2015, 03:43:24 AM

Now that is some cap porn, they are lovely :)

Title: Re: Shunt or Series Stepped Attenuator.
Post by: EarWorm on June 29, 2015, 10:02:05 AM

Grabbed two of these for the output caps a few months back when HiFi collective had them at an excellent price.   MCap EVO Aluminum Oil.     Porn is porn.   :)