Current-to-voltage conversion in all cases is done by a resistor somewhere in the circuit.
In some cases the resistor is obvious on the current output of the Sabre (or other current output DAC chip, like the PCM1794) and in other cases the resistor is buried somewhere in the I/V circuit. When the resistor is separate, like on the DAC output, it is immaterial if you do current amplification before the resistor or voltage amplification after the resistor. When the resistor is buried, the question is moot.
Different designers will have different philosophies as to which approach is better, and there are good (and bad) examples of separate I/V resistor designs and buried I/V resistor designs.
Dave
In some cases the resistor is obvious on the current output of the Sabre (or other current output DAC chip, like the PCM1794) and in other cases the resistor is buried somewhere in the I/V circuit. When the resistor is separate, like on the DAC output, it is immaterial if you do current amplification before the resistor or voltage amplification after the resistor. When the resistor is buried, the question is moot.
Different designers will have different philosophies as to which approach is better, and there are good (and bad) examples of separate I/V resistor designs and buried I/V resistor designs.
Dave
Russ White said:
I must correct myself here. This is what happens when you post after a long day at your daughter's dance recital.
In reality the there is no voltage gain with the IVY as I have it configured , in fact there is slight loss.
All that really matters is the output is 2VRS at 0dB output.
Cheers!
Russ
Hey guys,
just to let you know I just built my Buffalo after the normal startup-problems: soldering station was missing/lost (i recently moved to a new house), out of solder (on sundays), no room to work, you know how it goes
.
Current state: spaghetti! I plan to put it in a nice case sometime, but i'm really waiting (lurking in the dark) for the uber controller.
Soundwise: *very* good. Wide, stable, accurate soundstage. Quite neutral, i think. Lots of detail, especially in the lower (bass) regions.
I'm using it with a sonos as source (the only thing I had with volume-controlled spdif output, for lack of balanced diff. preamp) and a pair of UcD400's as amp.
just to let you know I just built my Buffalo after the normal startup-problems: soldering station was missing/lost (i recently moved to a new house), out of solder (on sundays), no room to work, you know how it goes
.Current state: spaghetti! I plan to put it in a nice case sometime, but i'm really waiting (lurking in the dark) for the uber controller.
Soundwise: *very* good. Wide, stable, accurate soundstage. Quite neutral, i think. Lots of detail, especially in the lower (bass) regions.
I'm using it with a sonos as source (the only thing I had with volume-controlled spdif output, for lack of balanced diff. preamp) and a pair of UcD400's as amp.
Attachments
OK, I got the SACD transport but it is not the 230v I will need when I go back overseas. I will need to buy a transformer to get 110v and I want to make it balanced power. If I understand correctly I need a 230V to +/-55VAC transformer right? Would the LCDPS/Buffalo benefit from being run at 110v on that same transformer or should I wire it for 230V and only use the converter for the DVD player?
Haiku I/V stage
Hey folks,
Some of you may be interested in this thread I started about my Haiku I/V stage which I am testing with the Sabre chip.
http://www.diyaudio.com/forums/showthread.php?postid=1552427#post1552427
Cheers!
Russ
Hey folks,
Some of you may be interested in this thread I started about my Haiku I/V stage which I am testing with the Sabre chip.
http://www.diyaudio.com/forums/showthread.php?postid=1552427#post1552427
Cheers!
Russ
Ah fair enough fierce....
I'll stick with the IVY and see how it goes. Will have to try it with the aikido HPA. But this one is really destined for the main rig and to be fed with either the squeezebox or CDP.
Looking forward to the build now. Will this thing fit OK in a smaller case - say the size of a zhaolu type DAC do you think? (I'm thinking of separation from transformers).
Fran
I'll stick with the IVY and see how it goes. Will have to try it with the aikido HPA. But this one is really destined for the main rig and to be fed with either the squeezebox or CDP.
Looking forward to the build now. Will this thing fit OK in a smaller case - say the size of a zhaolu type DAC do you think? (I'm thinking of separation from transformers).
Fran
Hi NeoY2k,
The Sabre DAC clock input is a simple CMOS 3.3 input. Sorry if this is not what you had hoped.
Hi All,
I have a very interesting question for you guys. I had a person I trust and feel has very good ears and he made this comment about one of the Sabre refference designs.
"The highs are very good/crisp...... however the lows sound dullish. He then hinted that it might be the exturnal circuit that was on the refference board, but didn't go into anymore details. I was hoping some of you on this site might be able to share with me why this phenomina may occur. I would like to change the refference design and convince this guy that the lows can be just as good as the highs.
Dustin
The Sabre DAC clock input is a simple CMOS 3.3 input. Sorry if this is not what you had hoped.
Hi All,
I have a very interesting question for you guys. I had a person I trust and feel has very good ears and he made this comment about one of the Sabre refference designs.
"The highs are very good/crisp...... however the lows sound dullish. He then hinted that it might be the exturnal circuit that was on the refference board, but didn't go into anymore details. I was hoping some of you on this site might be able to share with me why this phenomina may occur. I would like to change the refference design and convince this guy that the lows can be just as good as the highs.
Dustin
Welcome back Dustin,
Its interesting you should say that, as everyone here who has auditioned my DAC speaks very well of the bass. But it is two different circuits.
I do have a question for you.
What harm if any would be caused by running the outputs directly to an I/V stage which has its input at 0V potential, and not 1.65V.
The reason I ask is that I have a discrete zero global feedback design in the works and I want your input.
Right now I am making provision to set the common mode input voltage 1.65V, but it would be much simpler to make it 0V
You can see it here:
http://www.diyaudio.com/forums/showthread.php?postid=1556739#post1556739
Cheers!
Russ
Its interesting you should say that, as everyone here who has auditioned my DAC speaks very well of the bass. But it is two different circuits.
I do have a question for you.
What harm if any would be caused by running the outputs directly to an I/V stage which has its input at 0V potential, and not 1.65V.
The reason I ask is that I have a discrete zero global feedback design in the works and I want your input.
Right now I am making provision to set the common mode input voltage 1.65V, but it would be much simpler to make it 0V
You can see it here:
http://www.diyaudio.com/forums/showthread.php?postid=1556739#post1556739
Cheers!
Russ