Claus, tak for links, det var nyttig lekture.
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Buyer: FAQ hos Lehmann siger:
Q: What should be preferred: a high gain with plenty of reserve for the volume pot or a low gain with a volume setting between 12 and 4 o’clock?A: As long as you can realise a volume setting that is loud enough, the low gain setting is to be preferred. As a matter of fact potentiometers tend to have a weaker channel balance in the lower volume range. Secondly the danger of cranking up the volume to insane and dangerous levels is minimised.
Q: On my Linear I have set the dip switches to 0dB. To get a decent volume, the volume control is between position 12 and 1 o'clock. Is this normal? Would altering the DIP-switches to 20dB give me the same volume level without moving the volume knob to such high positions? Do the different gain settings affect sound quality in any way?A: We recommend to leave the gain settin at 0dB. At 12 o'clock you still have 20dB of reserve. If you choose a higher gain setting, you will have to turn down the potentiometer to a lower level and also slightly increase the noise.
Using higher gain settings is only recommended in cases where the potentiometer reaches the maximum level and volume is still insufficient. This is highly depending on the efficiency of the headphone in question.
Buyer, jeg ved ikke om din kommentar var ment som en spørgsmål, men ovenstående er en yderligere indgang til gain-problematikken. Det er det logaritmiske potentiometer konstruktionsmåde, der giver dårligere kontaktvilkår og styring (og mere støj) i rand-områderne, lavt
og højt. Ud fra den betragtning giver den mening at have kl.3 som normal-til-høj lyttestyrke. Der er stadig lidt at gå på, før potentiometerets indbyggede svaghed kan høres i det høje rand-område.
Der er andre konstruktionsmåder for en lydstyrke-kontrol, men det logaritmiske potentiometer er tilsyneladende det fremherskende indenfor audio-domænet (hi-fi/head-fi/mm). Sikkert fordi det har sine styrker, men det har så også sine svagheder.
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Ampere/Volt/Ohm/Watt/Power/Gain/Impedance/Sensitivity/Efficiency/Potentiometer - sjovt, hvordan ting begynder at hænge bedre sammen, når man graver lidt