Re: Re: Thanks for the info...
Lots of cool ideas coming!
If the complex firmware for your AC1 or Volumite is not finalized yet, could you please consider configurable I2C addresses or ascertain some special ones to be unused? A potential DIY thing could be to use the VGA port of a media PC to change volume, but for this the I2C addresses 0x37 and 0x50 should stay reserved.
Russ White said:
Lots of cool ideas coming!
If the complex firmware for your AC1 or Volumite is not finalized yet, could you please consider configurable I2C addresses or ascertain some special ones to be unused? A potential DIY thing could be to use the VGA port of a media PC to change volume, but for this the I2C addresses 0x37 and 0x50 should stay reserved.
transformers and buffalo
I have just ordered the buffalo combos, but I have thought about using transformers as I/V or V/V stage for a long time.
Gordon Ranking uses transformers as well, in V/V mode, and Audio Consulting Serge Schmidlin sells different transformers with silver windings for this purpose.
For me the topic is still not absolutely clear:
If there is bias on both sides, the transformer would not see any dc at all, wouldn´t it?
But is there an "idle" current in voltage mode? If yes, where can it flow to?
As soon as you are going to use step up transformers, there is dc that wants to flow to negative, you have partially or full current mode, depending on the step up ratio. So you have to use a transformer with separate windings to make up a centre point, where the current can flow to. Then there is the question about the imbalance of the transformer:
Maybe in voltage mode the transformer has no bad influence on balance, but in current mode it could destroy the THD figures of the buffalo,
because it won´t be possible to build a transformer balanced as precisely as an IVY.
These are my thoughts, but I am not sure about them. I would be very pleased if there is an expert, who could clarify.
I thank you for help-
I have just ordered the buffalo combos, but I have thought about using transformers as I/V or V/V stage for a long time.
Gordon Ranking uses transformers as well, in V/V mode, and Audio Consulting Serge Schmidlin sells different transformers with silver windings for this purpose.
For me the topic is still not absolutely clear:
If there is bias on both sides, the transformer would not see any dc at all, wouldn´t it?
But is there an "idle" current in voltage mode? If yes, where can it flow to?
As soon as you are going to use step up transformers, there is dc that wants to flow to negative, you have partially or full current mode, depending on the step up ratio. So you have to use a transformer with separate windings to make up a centre point, where the current can flow to. Then there is the question about the imbalance of the transformer:
Maybe in voltage mode the transformer has no bad influence on balance, but in current mode it could destroy the THD figures of the buffalo,
because it won´t be possible to build a transformer balanced as precisely as an IVY.
These are my thoughts, but I am not sure about them. I would be very pleased if there is an expert, who could clarify.
I thank you for help-
Hi Rolls,
Here is a page on using a transformer on the output of a current output DAC. The DAC in the article is the PCM1794, but the idea is the same for the Sabre.
Dave
http://www.raleighaudio.com/passive_output.htm
Here is a page on using a transformer on the output of a current output DAC. The DAC in the article is the PCM1794, but the idea is the same for the Sabre.
Dave
http://www.raleighaudio.com/passive_output.htm
David Davenport said:
Me personally, I want Both.
As I firmly believe the two tend to be complimentary attributes.
But I am also wise enough to know my tastes are not necessarily the same as anybody else.
But still, I am hard pressed to put a -90db thd output stage on a -120db DAC.
But I know plenty of folks will, and even some much worse. And that's OK, it is just not for me. Especially since I do a lot of my listening with headphones. I want the music to be reproduced as accurately as is practical.Cheers!
Russ
Russ White said:SPDIF MUX is tested and working, but there is one small error on the this first run PCBs which requires you to install a small wire jumper if you want your "LOCK" LED to work.
Luckily there is a pad right next to the LED pad which you can bridge to connect it to GND. This will make the LED light happily when the signal locks. I will post pic of it later.
The circuit itself functions wonderfully. I am using it right now.
We will probably make this run of boards available to anyone who wants them very soon. I think there are 20 or so left. Not sure.
The MUX allows 4 inputs 3 can be standard consumer SPDIF and one AES.
The output is both SPDIF and I2S.
There is a 4 pos DIP for selecting various settings for the CS8416.
I will get a manual done for it soon.
Cheers!
Russ
Could you please some insight in how the input switching will work for the mux? Can we use a rotary selector for it or is it made for up/down buttons?
MrMajestic said:
Sure, basically there are 2 inputs which represent a two bit binary number. You can use a 2 pole 4 pos switch (like a rotary switch) or a microntroller (or maybe a counter or some other logic device) to step through the sources.
There is a pin header on the board with the that looks something like this VDD,b1,b2,GND.
Cheers!
Russ
SPDIF Switch
Can I use the TwistedPear Darwin to select my SPDIF source or is the MUX a much better implementation.
I plan to intergrate the buffalo when it arrives into a preamp. I will have 3 analog inputs and three digital.
I was planning on using the Darwin to select each source. The analog inputs would use output 1 of the Darwin driving directly to a volume control and the digital sources would use output 2 driving the buffalo then the volume control.
Can I use the TwistedPear Darwin to select my SPDIF source or is the MUX a much better implementation.
I plan to intergrate the buffalo when it arrives into a preamp. I will have 3 analog inputs and three digital.
I was planning on using the Darwin to select each source. The analog inputs would use output 1 of the Darwin driving directly to a volume control and the digital sources would use output 2 driving the buffalo then the volume control.
Re: SPDIF Switch
I would not use the Darwin that way. Routing the digital and analog signals close together like that is probably not a good idea.
The MUX is a much better solution for selecting digital sources.
Using the Darwin to select analog signals is still just fine.
Cheers!
Russ
npapp said:
I would not use the Darwin that way. Routing the digital and analog signals close together like that is probably not a good idea.
The MUX is a much better solution for selecting digital sources.
Using the Darwin to select analog signals is still just fine.
Cheers!
Russ
Russ,
Besides using a digital volume control, I am more inclined to build a variable analog output for the Buffalo dac (something similar to Lavry DA10).
Can IVY be modified slightly to support variable output (e.g. varying R1-4 or R5-8)? or will the upcoming Conterpoint be a better option?
Thanks
Nacder
Besides using a digital volume control, I am more inclined to build a variable analog output for the Buffalo dac (something similar to Lavry DA10).
Can IVY be modified slightly to support variable output (e.g. varying R1-4 or R5-8)? or will the upcoming Conterpoint be a better option?
Thanks
Nacder
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