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Quickie: Apple iPhone Lightning Headphone Adapter

Arnandsway

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#21
Sure. But it will, of course, depend on the amp, how loud you play music, and whether or not there's any other amplification. In my system, for example, I have a choice of a Didden-modified DCX2496 or a miniDSP 2x4HD. The former can be driven to full output with the 1V, the latter will fall 6dB short. I have never found that I couldn't get things uncomfortably loud with the latter, so for me, it's not a dig deal.
To what input sensitivity in dB does this correlate, for the DCX2496?
 

SIY

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#22
Good question, and I don't know the answer off the top of my head (I'm a few dozen miles away from it at the moment). But since this is the Didden-mod version, the numbers won't correspond to stock DCX2496 anyway.
 

Arnandsway

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#23
Good question, and I don't know the answer off the top of my head (I'm a few dozen miles away from it at the moment). But since this is the Didden-mod version, the numbers won't correspond to stock DCX2496 anyway.
Alright. Curious if anybody else knows this. (Also what dB correlates for a voltage of 2V.)
 
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#25
Input sensitivity (V rms) =

Square root (Rated power x ohm Load) divided by
10 to the power of gain / 20.


Example:
I have an amplifier rated at 200 watts into 8 ohms, with 26dB gain;

Input sensitivity
= square root (200 x 8) / 10^(26/20)
= square root 1600 / 10 ^ 1.3
= 40 / 20
= 2 (V RMS)

In other words, I need an input of 2V RMS to output 200W RMS from my amplifier.

Most consumer disc players standardise to around 2V RMS.

Now if I use a dongle or phone with only 1V RMS, that is 6dB less than 2V RMS.

A 6dB reduction in power is not half, but a QUARTER of the power rating.

So if I hook up this dongle with its maximum output of 1V RMS, the maximum power my amplifier will now deliver is 50W RMS.
 
Last edited:

Arnandsway

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Joined
Sep 13, 2018
Messages
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#26
Input sensitivity (V rms) =

Square root (Rated power x ohm Load) divided by
10 to the power of gain / 20.


Example:
I have an amplifier rated at 200 watts into 8 ohms, with 26dB gain;

Input sensitivity
= square root (200 x 8) / 10^(26/20)
= square root 1600 / 10 ^ 1.3
= 40 / 20
= 2 (V RMS)

In other words, I need an input of 2V RMS output 200W RMS from my amplifier.

Most consumer disc players standardise to around 2V RMS output.

Now if I use a dongle or phone with only
1V RMS, that is 6dB less than 2V RMS.

A 6dB reduction in power not half, but a QUARTER of the power rating.

So if I hook up this dongle with its maximum output of 1V RMS, the maximum power my amplifier will deliver now 50W RMS.
Thank you for the clear explanation!
 
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#27
They apparently DO care if it involves me doing things that will not make them money. Like moving my WAV files from computer to phone or vice versa, changing computers and transferring files that I did not purchase from them to or from my phone...
I won an iPod shuffle in a raffle, I tried to drag some files onto it to no avail. My son said you can't do that you have to install iTunes. Right in the bin it went, people don't get why I have nothing to do with Apple products.
 

SIY

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#28
I won an iPod shuffle in a raffle, I tried to drag some files onto it to no avail. My son said you can't do that you have to install iTunes. Right in the bin it went, people don't get why I have nothing to do with Apple products.
Scott gets it. I only have them because my job pays for an iPhone and issued me the MacBook Pro.
 
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