DIY amp volume pot slow vol increase help

[Tubeglowpio]

Hi everyone, I'm working on a 5 watt Bluetooth portable speaker for my mother in laws Christmas gift. I'm using the very simple audio amp chip LA4425, I've built these and others before and always get this one sounding very nice for the price but I cant figure out how to make the volume pot increase in volume slowly and to restrict it from reaching full vol due to distortion. This is a high gain chip and cant change it, I've tried putting a resistor on my input but it doesn't do much and acts more like a filter and I lose some of my body to the music. I've tried 10k and 50k to no success and 10k sounds the best.

 

[toddalin]

Are you using a linear or logarithmic pot? You should probably be using a logarithmic taper for audio.

 

[whoaru99]

As far as limiting the amp from distortion/clipping by somehow manipulating the volume pot or resistors/resistance, I think that's largely ineffective. If you pad down the input so much as to preclude distortion/clipping with any possible input then I think the amp might be limited to such small effective gain it may not even be practical/useful to use.

Remember, volume controls/input attenuators are not power controls, per se. All they do is change the ratio of output to input. With enough input you can still drive enough output to distort/clip.

Rather than try to somehow artifically limit it, perhaps a bit of hands on training showing what distortion sounds like so she knows when, rather than where, to stop.

 

[Tubeglowpio]

Thanks for the replies, it is a audio taper pot yes. I'm thinking I could make a stepped attenuator to limit the volume increase but that's prob about 30-40 bucks more on a 20 dollar circuit I could maybe add a class a biased small signal transistor before and control the gain with that? The amp is fine for me to use but the pot is too touchy for for her to use, maybe I could find three good volumes and use a triple throw switch to select 3 different voltage/volume dividers.