Volume setting question - smaller version

humblebee

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So, heres what I did, let me know if this is ok.
My sound card output is line level consumer, so around 1.44v. Amp sensitivity is 200mv. So my calculation was to reduce sound card output by 20db which would bring it to around 200mv output. (1440/7 ~200mv; hence 3dbx7~20db )
So by doing this, even if the volume knob is pushed to its max, it wont go beyond the amps max capability.
 
What is 3dBx7 ? You dropped the signal level in 3 dB steps via software control ?
Might be better to just let the card output the full signal and use a voltage divider ( 2 resistors...or even one...in each channel ) at the output of the card / or input of the amp......if you really need to do this !
You can even use it directly as it is ,except that the amp will reach full volume with just a partial rotation of the volume control. Try it. 1.4 V into the amp will not kill it and in any case the amp will see only what the volume control sends to it. So the volume control is like a gate keeper. Its signal to the amp will depend on it's position. The 1.4 V will go past it only if you turn it to it's maximum position.

The only problem you "might" face is that small changes in the position of the volume control might cause the volume to change quite a lot. But this sensitivity depends on a lot of factors. If you are lucky , in your system the sensitivity might be acceptable. TRY it ! An alternative simple solution is to try a 10 K resistor in series in the signal cable to the amp. It will drop the signal to the amp , depending on the resistance of the volume control. Try all the simplest solutions first. Simplest being just connect it directly . You can't damage your amp.
Note that you need to have some extra input capability to take account of recordings that are made at lower levels. At least say 6 dB more. This will help to reach full output even with low level recordings. I'm guessing you might just be able to get away without adding anything and tolerate the sensitivity of the volume control position !

PS: Wow, just noticed your location . Glad to meet you ! This must be the first communication we have had from the 'other side' where we all go to after shedding our current garb. I guess there are no countries there...must be just one BIG country ? Hmmm....and there is hi-fi too...! Great ...that's really good news. Keep in touch ! :D
 
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Thanks for the answer.
Yes my sound card shows sound in dbs, so I can drop 20dbs. And since we have an analog volume control here, I guess we wont lose sound quality as well, as compared to reducing sound in windows which is digital.
So, I am guessing that I am doing the correct thing.

I had another question. If we engage full bass and treble, brochure says we get 10db jump for each, though it doesnt feel that much.
So now I decrease it by 40db?

Hmm, nice to meet you earthling. Though you must know that you were never alone. Everybody doesnt go to my realm which is in the Pole Star system. Yes, people don't particularly feel the need for 'possessing' land there. And yes, theres live music only, and thats why im getting into a system that at least gives me some feel.
Look its all about consciousness. Take your time, its not impossible. (Serious)
 
If your bass and treble boost don't sound much, it could be because of their characteristics like max boost and the frequency at which it starts doing it. But to really know what's happening you will need to check it out with some test instruments or run a FFT program while playing a frequency sweep or pink noise. Maybe it's possible the tone controls are not working in the first place ! There is more to say about all this, but it's too much to type out in an email. For example: If the sound card has a 2 Volt output limitation and it's running flat out and then you boost bass and treble it could cause signal overload and clipping ! I don't know the set up so I can't even guess what's happening. I'd just ignore any tone controls !

The effect of the tone controls should be audible at any volume level. No need to reduce the sound card level. It will not help in any way ( apart from overcoming any clipping !). But I think a good recording through decent speakers won't require a tone control !

I'm not an Earthling. I'm a Rearthling ! The reluctant earthling ! :) I didn't want to be here. Just passing by ! Too much gravity, it's slowing me down ! ;)
 
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