I deliberately measured low and high values to get an insight. The 4500 are just low bias settings. They are also valid, but deliver a roughly 1volt rms output where else you would have 1.2 volt rms....
With the somewhat lower bias and output you “gain” a small amount of less distortion, but the difference is minimal. The values are accurately measured though with the AP ...
The 5500 metric tells you, that within acceptable THD you will get the most output signal; 1.2 v rms roughly
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Hello everybody! Four years later, I'm back 
I have decided to finish my DDDAC, the first step will be to replace my USB to I2S, the WaveIO died 2 years ago for no reason and since then, I use a cheap board.
The "source" is a Beaglebone Black board running volumio. I read great feedback for ARMATURE HECATE XCORE 208, would it be a good choice ?
Thank you !
Julien
I have decided to finish my DDDAC, the first step will be to replace my USB to I2S, the WaveIO died 2 years ago for no reason and since then, I use a cheap board.
The "source" is a Beaglebone Black board running volumio. I read great feedback for ARMATURE HECATE XCORE 208, would it be a good choice ?
Thank you !
Julien
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I would like to switch to the FiFoPi instead of the HifiBerry I am using. Since I am a electrical noob, I would like to use the set-up Doede uses to power the FiFoPi:
So, I will use the LDOVR to get 3.3V from the 12V power supply as described by Doede. I do not see a heatsink in the picture, is that not necessary? Or is it better to use one for long term reliablity?
In addition, just to bee sure, since a 165 Ohm resistor is not available, I assume it's no problem to use a 169 Ohm resistor instead?
Regards, Anton
So, I will use the LDOVR to get 3.3V from the 12V power supply as described by Doede. I do not see a heatsink in the picture, is that not necessary? Or is it better to use one for long term reliablity?
In addition, just to bee sure, since a 165 Ohm resistor is not available, I assume it's no problem to use a 169 Ohm resistor instead?
Regards, Anton
@billyboyk.... Well, I don't know the ARMATURE HECATE XCORE 208 but it looks nice. I would however consider taking the i2s signal directly from the BBB and into the Ian Canada FiFoPi reclocker. This way you would bypass both USB- and Spdiff conversions and also get some serious reclocking and isolation of the signal along the way. Especially if you change the crystals to something better than stock.
You would need to place the BBB and FiFoPi close til the DDDac though...
You would need to place the BBB and FiFoPi close til the DDDac though...
no need for a heatsink. The resistor gives a drop of voltage making sure the LDO is not dissipating too much.
value is not critical…. 169 is ok
Power Headroom for I/V resistors
Hello Gents,
I am planing to purchase Wishay/Texas Zfoil resistor for my four deck DAC.
They are rated for 0.6W and will be (if I didn't mess) running at 0.22W.
I wonder if headroom is enough to have the resitors giving soundwise the best of what they can.
Any light on the subject welcome.
Thank you,
Tristan
Hello Gents,
I am planing to purchase Wishay/Texas Zfoil resistor for my four deck DAC.
They are rated for 0.6W and will be (if I didn't mess) running at 0.22W.
I wonder if headroom is enough to have the resitors giving soundwise the best of what they can.
Any light on the subject welcome.
Thank you,
Tristan
Power Headroom for I/V resistors
Hello Gents,
I am planing to purchase Wishay/Texas Zfoil resistor for my four deck DAC.
They are rated for 0.6W and will be (if I didn't mess) running at 0.22W.
I wonder if headroom is enough to have the resitors giving soundwise the best of what they can.
Any light on the subject welcome.
Thank you,
Tristan
Hello Gents,
I am planing to purchase Wishay/Texas Zfoil resistor for my four deck DAC.
They are rated for 0.6W and will be (if I didn't mess) running at 0.22W.
I wonder if headroom is enough to have the resitors giving soundwise the best of what they can.
Any light on the subject welcome.
Thank you,
Tristan
Sorry, I did not see your message. With FifoPi I take I2s from BBB and send i2s to DDDAC ?