Attenuation

Anyone had any experience attenuating a balanced cable?

Any thoughts? I'm not paying £69 for a Rothwell balanced attenuator, and I don't want to change my cable if I can avoid it.

I've got about 5 degrees usable volume control and it's starting to seriously nark me off.

 

My thoughts are:

39KOhm in series on the hot wire, and then a 9K1 shunt between hot and signal return. This should give about 16dB, should it not?

 

if its fully balanced youll need to do the same to the - (pin 3 on xlrs) wire,if you use a couple of pots you can find the ideal values and then replace them with fixed resistors

 

I'm not really sure. Reading through the manual NAD refer to the - pin as 'signal ground'. Implying that it's not + and - as such as just having a seperate signal ground to the sheild.

In your method I presume you'd put a series resistor in + and - and then a shunt between + and shield and - and shield, right?

 

The manual says this:

Pin 1 : Chassis Earth (Ground)
Pin 2 : Hot (Live)
Pin 3 : Signal Ground (Return)

 

yep,but the discription given by nad makes it look like its not a balanced system,so your origanal idea will work

 

Well, it would appear that my DIY skills haven't totally deserted me (see mains filter thread).

Just finished attenuating my cable and it works a treat. There is a slight improvement in the sound, mainly because my amps tonal balance seems to change slightly as it moves away from minimum volume (I was previously always near minimum, unless I fancied a bit of ear bleeding). Now I can run around the dial a bit more and listen at normal levels with the tonal balance I 'enjoyed' at the higher levels. Basically the bass is in better proportion at lower volumes.

Having said all that, I could be making it all up in my head - but I don't care. The attenuation served it's primary purpose of giving me more range on the volume control, meaning I can now realistically use the remote to adjust volume.

Woo hoo.