Again, I want to make a U-Pad.
http://3.bp.blogspot.com/-NH_cxciYf...T4IBGMLdKnQ/s1600/balanced_pad_attenuator.png
Uneeda Audio - Build your own attenuator pads
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I need to make a simple U-Pad, to convert a 600 ohm balanced signal from +4dBu to -10dBV
I can't for the life of me figure out the calculation.
Can someone help a brother out?
- THANKS.
A Jensen app note has the resistor network for this conversion.Helpful web page for you:
Convert between dBu dBV and RMS Volts
I don't remember which one. There are over a dozen, so it will take some searching.
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No one can just calculate the values?
For a matched 600R source, with the output -12dB (with a light load),
the series resistors are each 150R, and the shunt resistor is 300R.
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I had a look through my Jensen AN last night and did not see the resistor network.A Jensen app note has the resistor network for this conversion.
I don't remember which one. There are over a dozen, so it will take some searching.
Maybe it was another of the balanced retailers that published it.
I do remember having to work through it because intuitively it did not make sense. Took a little while to understand why they placed the resistors in the arrangement they showed.
Thanks, Rayma ! And thanks to all for the help.
Remember this calculation relies on the source impedance being 600R,
and also the load being >>300R (say at least 3k or more).
..... No one can just calculate the values?
I just did. The "true 600r" case and a more real-world case around 2,400r.
Is my image not showing for you?
Two L-pads connected in Balanced mode. Try 2250R for the 2 series resistors and 750R for the 2 shunts with their midpoint connected to audio ground. Input/output impedances are 6000R and 1125R Balanced respectively.
SO.....
No one can just calculate the values?
I'm totally stuck here.
I just did. The "true 600r" case and a more real-world case around 2,400r.
Is my image not showing for you?
Nice walkthrough/example. Textbook quality stuff
Textbook quality stuff
It's a matchbook size problem. Dunno why it needed so much thread space.
It's a matchbook size problem. Dunno why it needed so much thread space.
Well, I have a matchbook-sized understanding of such things.
But actually, given the somewhat wide swing in the responses, maybe it's not really so simple?
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