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bumpy
08-10-2019, 07:37
The output of my CD player is a bit too high for my integrated amp meaning the volume control on the amp only works over a small range before being too loud. I am led to believe this may be causing some distortion to the music, although that is not immediately obvious.

The general recommendation is to use in-line attenuators like Rothwell, but I have a spare passive volume control that I could put in line before the integrated. Is there anything that I should be aware of with this approach? This would only be a temporary fix but it might give me a handle on whether permanent changes are needed.

https://m.media-amazon.com/images/I/31a8TJjEkJL._AC_UL320_ML3_.jpg

Light Dependant Resistor
08-10-2019, 08:29
Hi Chris
If using a passive volume control, try it at half volume as it should if its a conventional attenuator provide equal resistance from your source, and
the same value of resistance to ground. In electrical terms it is a L pad. The RCA solution is likely to be internally also two resistors doing the same thing
but may be higher or lower in resistance, this is where a multimeter comes handy to check.

The passive volume control you have, therefore is a neat solution, let us know how it goes.

bumpy
08-10-2019, 08:37
Thanks Chris

The advertising for these attenuators targets distortion caused by overloading the amps. I cant get my head around how one can still 'overload' the amp if the volume is right down to low levels. Surely this negates the overload.

Light Dependant Resistor
08-10-2019, 08:57
Hi Chris
Yes attenuation certainly does negate the possibility of overload. Most amplifiers provide for CD levels. If we measure a typical CD players
output it cruises along most of the time, at about 200mv only a 10th of its true capability for delivering output voltage and current. But there are CD's
that will use all of the available level, like about 5 mins in to Mike Oldfields Amarok .... have you heard that one ?

Any given amplifier, really does NOT need to amplify a CD input, rather just variable attenuation is sufficient to pass to its power amplifier stage
or to a separate power amp. Hence you can keep the CD audio as clean as possible by not adding or subtracting from its enormous capability.
There is more on the wee silver disc's than we casually appreciate. although i do have some criticisms of it, they are minor.