So the 2 adapters (XLR to RCA and RCA to 3.5mm headphones) for Rev2 version hasn't changed output impedance at all for headphones use?
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So the 2 adapters (XLR to RCA and RCA to 3.5mm headphones) for Rev2 version hasn't changed output impedance at all for headphones use?
OP
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- #22
The output impedance is measured without adapters, the adapters will add a little bit but the resistance of the wires inside the adapter is almost negligible.
Veri
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good question
Can you please measure and confirm with these 2 adapters, for 3.5mm headphones use?
If you have a spare moment...
OP
- Thread Starter
- #25
I will try to get this done later today.
Veri
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He has an audio precision analyser, so he can connect it to the output and measure output impedance. The only variable is in his cabling/interconnects which add their own impedance.
OP
- Thread Starter
- #28
I use the audio precision damping factor measurement utility with an APx525.
https://www.ap.com/technical-library/measuring-amplifier-damping-factor-with-apx500/
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OP
- Thread Starter
- #29
Here you go
Damping Factor Balanced (XLR) = ~220
Damping Factor RCA with XLR to RCA Adapter and Headphone Adapter = ~260
Veri
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260Ω ?
or am I reading this wrong?
OP
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- #31
No that is the damping factor. The damping factor does not have a unit.260Ω ?
Veri
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Ohhhh. Maybe you could PM @amirm or @WolfX-700 they should have an APx project file for output impedance like so
OP
- Thread Starter
- #33
Ohhhh. Maybe you could PM @amirm or @WolfX-700 they should have an APx project file for output impedance like so
The damping factor is a ratio between the output impedance and the load (32ohm) in this scenario so the
Output impedance for a balanced connection is 32/220 = 0.145 ohm
Output impedance for RCA connection is 32/260 = 0.123 ohm
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What's the load?
Veri
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By “RCA connection“ you mean with XLR to RCA adapter?
And does that include RCA to 3.5mm for headphones connection?
OP
- Thread Starter
- #37
Thanks, so for a headphones that peaks at 400ohms, output impedance is 400/260 = 1.5 ohms?
OP
- Thread Starter
- #39
No. The output impedance is 0.123ohm as I calculated earlier.
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