Laptop Headphone to Hifi AUX

nilblade

Member
2014-12-22 10:38 pm
I hope I am posting this in the right place, sorry if not...

I am currently connecting my laptop via headphone jack, I have no line out) to the AUX on my hifi (Panasonic SC-HC29DB), I am finding that the volume on the laptop has to be 50% or more to get a decent sound on my Hifi. Is this normal?

Would a USB DAC /Headphone amp help?

What signal level is expected by the AUX jack, and what is the headphone port on the average laptop able to provide. I have some idea of what the issue is - but Im not sure what the correct solution is

if some one could point me in the right direction - it would be appreciated

Thanks

I am finding the same occurs when connecting to the hifi via bluetooth.
 
I am currently connecting my laptop via headphone jack, I have no line out) to the AUX on my hifi (Panasonic SC-HC29DB), I am finding that the volume on the laptop has to be 50% or more to get a decent sound on my Hifi. Is this normal?

From my understanding, it is normal. When you connect, say, a CD player, the signal out is the unattenuated signal (100%) which is then modified by the analog pre-amp volume control. A volume control reduces the signal substantially, effectively nearly 100%, at the anti-clockwise point of rotation, and progressively reduces the impedance allowing a higher signal voltage through to the amplifier section as the volume control is rotated clockwise. Many, including mine, also boost the signal when it gets past a certain point.

You could leave the the laptop volume at 100% and just use hifi volume control. Alternatively, if there are other inputs to the hifi, you could set a level so that all will have roughly the same volume at the same point of volume control rotation. I use Daphile and set the initial volume at 25% to avoid the possibility of blowing my active speakers up, if the pre-amp is wound up too far.
 
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My parents have a similar (older) Panasonic unit, and as you may have guessed, the line-in requires a fair bit of oomph even in high gain mode, and I usually preferred to use my Clip+ via a portable headphone amp.

Specifications on this unit are pretty dire, unfortunately, yielding no more than the aux input being a 3.5 mm job. <insert page-long rant on how not all consumers are f***ing idiots and manufacturers should be ashamed of themselves here>

Maximum output level would depend upon sound chip and its implementation. If it's got a +5V analog supply available, expect 1.0-1.2V-ish tops. With +3.3 V only, more like 0.8 Vrms, and note that full output gain may run the output stage into clipping - verify with sine test tones. Software mixer facilities may reduce levels by a few dB.

Contemporary Windows versions allow switching between % and dB display in output device properties, Level tab, if you right-click the value. 50% typically corresponds to -10 dB, so the control characteristic is neither true lin nor true log.