The LM3886 you have ordered from Tom will be great.
The pot can sit between a high output source such as a CD player and the following power amp.
A pot between an amplifier and speaker is impractical because of all the power it has to handle. A 100 watt amp would need to be producing 100 watts all the time and the pot would determine how much or little went to the speaker. Typical listening levels are around 0.1 to say 3 watts. The remaining 97 would have to be dissipated as heat in the pot. It would also need to be a very low value (resistance) pot. Speakers like to be fed from a constant voltage source and directly coupling to a power amplifier achieves that. Adding series resistance (a pot in circuit) would also alter the overall frequency response of the speaker as its varying impedance interacts with the resistance.
So we don't do that
Adding a volume control between your phono stage and the power also has another benfit. When you lower the volume you also lower the intrinsic noise (hiss and hum) produced by the preamp.
The pot can sit between a high output source such as a CD player and the following power amp.
A pot between an amplifier and speaker is impractical because of all the power it has to handle. A 100 watt amp would need to be producing 100 watts all the time and the pot would determine how much or little went to the speaker. Typical listening levels are around 0.1 to say 3 watts. The remaining 97 would have to be dissipated as heat in the pot. It would also need to be a very low value (resistance) pot. Speakers like to be fed from a constant voltage source and directly coupling to a power amplifier achieves that. Adding series resistance (a pot in circuit) would also alter the overall frequency response of the speaker as its varying impedance interacts with the resistance.
So we don't do that
Adding a volume control between your phono stage and the power also has another benfit. When you lower the volume you also lower the intrinsic noise (hiss and hum) produced by the preamp.
The vol pot goes before the Power Amplifier section and after all the other gain stages/processing you require.
I am aware of an exception. If an earlier gain stage or processor is likely to be overloaded by a high incoming signal then you can precede that stage/processor with a sensitivity pot to limit the level of the maximum signal.
I am aware of an exception. If an earlier gain stage or processor is likely to be overloaded by a high incoming signal then you can precede that stage/processor with a sensitivity pot to limit the level of the maximum signal.
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