Hi bidule, tda1543A (note the "A" suffix) is a different critter, it´s digital format is NOT i2s.
This is completely new information to me. At first I thought that it had to be a non Philips product, but a quick search on the net told me that it is produced by Philips. What kind of format are we talking about and what could be the reason for making a different format? Anyone?
These dac chips were made for 90's cd players and there were different interface formats between the oversampling filter chip and the dac chip. This particular one we´re talking about (TDA1543A) is often referred to as the Japanese format.
http://files.pedjarogic.com/datasheets/Philips_TDA1543A.pdf
http://files.pedjarogic.com/datasheets/Philips_TDA1543A.pdf
Thanks. I can see now there has been a lot of confusion on this forum about this japanese version. Never knew about it. I would have replaced a blown TDA1543 with this TDA1543A version without knowing the difference.
George,
Did you compare your PCM1704 player with a standalone ad861 ? 660 ? Instead 3 x ad844 ?
I bet for something like you do but with a less "coldy" (if this word has sense) AD1862 (20 bits only!) than PCM1704.
Did you compare your PCM1704 player with a standalone ad861 ? 660 ? Instead 3 x ad844 ?
I bet for something like you do but with a less "coldy" (if this word has sense) AD1862 (20 bits only!) than PCM1704.
No, because for a few reasons.
I like the 844 because it has dc offset null pins to null out any dc from the dac, so does the BUF03 buffer, so everything is direct coupled from dac to output of the cdp.
It uses 15v rails which my cdp already had.
And it's not surface mount, which my eyes loath.
And I was very happy with it's sound 2 stacked not three for the PCM1704.
Three stack for the TDA1541 from what those guys have found.
Cheers George
I like the 844 because it has dc offset null pins to null out any dc from the dac, so does the BUF03 buffer, so everything is direct coupled from dac to output of the cdp.
It uses 15v rails which my cdp already had.
And it's not surface mount, which my eyes loath.
And I was very happy with it's sound 2 stacked not three for the PCM1704.
Three stack for the TDA1541 from what those guys have found.
Cheers George
I have a couple of original AD1862 reference design cards from 1988, you guys make me think I should resurrect them.
AD1862 and AD1865, two very interesting dacs to work with. I have my next iteration with the '65 planned, it will be a differential dac, one chip per channel. This way I should get a nearly constant current draw on the analog supply pins (except for small imbalances perhaps?).
Trouble with passive low value resistors is that you end up with no level, and you then have to boost the daylights out of the gain, and in turn the noise level comes up with it along for the gain ride, to get anything useful (>2v). You end up with much noise, and if you filter it out, you really start chopping into the audio signal.
I have yet to hear this passive resistor way give you a black silent background. Without a heap of filtering.
Cheers George
Well, I listen mostly to studio recorded music and would really like to try that sort of passive old-school circuitry in a dac. The sort of circuits that were used in good vintage gear. I think it could give a warm, vinyl-like character that will add to the enjoyment of music. I´m not too much into hi-res or precise soundstaging.
Good old vintage digital gear, was nasty, NE5532 and like as the I/V and brickwall filters, creating nasty sounds. Try to listen to the Sony CDP-101 today, ugly ugly ugly.
Cheers George
Cheers George
Hey, I´m talking vintage ANALOG gear, that was full of transformers! Apply that to a dac, like audio-note does... but on a budget. That´s what I mean.
Hey!! So why mention low value I/V resistors for doing I/V duties, as for transformers as I/V's, same deal, give them any gain they ring like a bell, so they need to be unity gain and need a big gain stage after them, welcome back noise.
Cheers George
Cheers George
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The idea is to drive the transformer from a low impedance, therefore the low value i/v resistor before it. And probably a buffer after the trafo. It´s just an idea, since the AD dacs were mentioned, sorry if off topic.
You just need to ensure your preamp's front-end has a low enough voltage noise. I've found AD605 when used differentially, and AD603 (single-ended) don't compromise the noise to any noticeable extent. In that noise in the recording always eclipses noise inherent in the DAC. This is for RBCD - if you want hires and 20bit noise floor then yes it becomes a more serious problem. Perhaps the solution for 20bits is going to consist of paralleled BF862s.....😎
Are anyone aware if there are fake AD844's out there?
Seems that eBay is the best price now, but it says China and makes you wonder. Some are for sale at USD $2.40
Anybody has any experience on this front?
Cheers, Joe
Seems that eBay is the best price now, but it says China and makes you wonder. Some are for sale at USD $2.40
Anybody has any experience on this front?
Cheers, Joe
Just how do you mean by 'burnt' - did they work at all or was pin 5 not there which means it could have been a re-badged cheaper current feedback IC?
.
As soon as they went into oscillation, in the same setup I knew they were fake and in the bin they went, and the RS ones then behaved as I've implemented in exactly the same position.
Cheers George