
Home  Forums  Rules  Articles  diyAudio Store  Gallery  Wiki  Blogs  Register  Donations  FAQ  Calendar  Search  Today's Posts  Mark Forums Read  Search 
Solid State Talk all about solid state amplification. 

Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving 

Thread Tools  Search this Thread 
1st November 2009, 08:46 PM  #1 
diyAudio Member
Join Date: Oct 2009

Attenuation
Hello,
I've tried attenuating my cd input using a 10k restistor as a jumper and a 6.8k to ground, it attenuated the input but not enough. Anyone know what values will double the above attenuation? Thanks. 
1st November 2009, 09:08 PM  #2 
diyAudio Member
Join Date: Feb 2002
Location: Western Sydney

__________________
Impedance varies with frequency, use impedance plots of your drivers and make crossover calculations using the actual impedance of the driver at the crossover frequency 
1st November 2009, 10:08 PM  #3 
diyAudio Member
Join Date: Oct 2008

"Twice" as much attenuation
If we assume that the load driven by the attenuator is kind of high, then your current attenuator (10K series, 6.8K shunt) has 7.86 dB of attenuation. To get "twice" as much attenuation, psychoacoustically, you add another 10 dB of attenuation. Your can do that by keeping the 10K series, and changing the shunt resistor from 6.8K to 1.5K. That attenuator, 10K series, 1.5 K shunt, gives 17.7 dB of attenuation, or about 10 dB more attenuation. This will sound about 1/2 as loud.

1st November 2009, 10:16 PM  #4  
diyAudio Member
Join Date: Oct 2009

Quote:


2nd November 2009, 11:16 PM  #5 
diyAudio Member
Join Date: Dec 2006
Location: Overtaxed Long Island, NY

In order for your CD player to sound its best you need to keep the players output impedance in mind. Specifically if its 47,000 ohms the attenuator should also have a 47,000 ohm impedance. With a resistor setup as you are playing with my guess its loading down the op amps and causing problems with distortion and excessive output current.
My elderly Sony CD player sounds it's best feeding into an attenuator that has a 100,000 ohm impedance. Even though it has LM4562's as the op amps and on paper they can drive a 600 ohm impedance. Look on line for attenuator calculators where you input impedance along with attenuation, lots of them out there. 
3rd November 2009, 06:13 AM  #6  
diyAudio Member
Join Date: Oct 2008
Location: Vancouver

Quote:
Last edited by cbdb; 3rd November 2009 at 06:17 AM. 

Thread Tools  Search this Thread 


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
attenuation using I/V  ailouros6  Digital Source  14  15th October 2008 06:20 PM 
XLR to RCA with attenuation pad.  KOL69  Everything Else  1  24th April 2008 11:10 PM 
hum attenuation  AndrewT  Power Supplies  3  2nd July 2006 09:12 PM 
10 dB attenuation box  june  Parts  2  20th July 2004 04:07 AM 
Attenuation  Nappylady  MultiWay  3  18th February 2003 12:07 PM 
New To Site?  Need Help? 