diyAudio

diyAudio (http://www.diyaudio.com/forums/)
-   Digital Line Level (http://www.diyaudio.com/forums/digital-line-level/)
-   -   TDA1543 NOS DAC-V4.5 - 24 bits ?! (http://www.diyaudio.com/forums/digital-line-level/214498-tda1543-nos-dac-v4-5-24-bits.html)

nowhere 14th June 2012 05:54 PM

TDA1543 NOS DAC-V4.5 - 24 bits ?!
 
Looking around at/for various DIY DACs I stumbled upon, for example, this one: TDA1543 NOS DAC-V4.5 - TeraDak Audio Electric Company .

And the page says:

Quote:

      • USB input
        • maximum supported sampling frequency : 96k/24bit

.

This sounds funny to me - the TDA1543 DAC is a 16 bit one.

It is possible to combine two 16 bit DACs in a manner that the resulting thing will be kind of 24 bit WRT resolution (not accuracy). I.e. at lower levels resolution will be about
24 bit, and at higher - still 16 bit.

But this requires certain HW and SW tri
cks - not just parallel connection as they typically do with TDA154.

So, is that 96K/24bit just false advertisement ?

Ken Newton 14th June 2012 11:00 PM

It is possible to configure multiple smaller DAC chips to create a single DAC chip of higher resolution. Burr-Brown has done that many years ago via their Colinear architecture as utilized in the PCM63 and PCM1704. To do so requires some non-trivial control logic, and DAC chips which are extremely well matched. It's much more likely that TeraDak has simply paralleled those TDA1543s, in which case the noise floor would be reduced, but the resolution would remain fixed at 16-bits.

My guess, and I emphasize, guess, is that the digital input receiver chip can accept 24-bits but is sending only the 16 most significant of them to the DAC chips. In which case the TeraDak would be 24-bit source compatible, but not deliver 24-bit signal conversion.

nowhere 14th June 2012 11:06 PM

Quote:

Originally Posted by Ken Newton (Post 3059896)
It is possible to configure multiple smaller DAC chips to create a single DAC chip of higher resolution. Burr-Brown has done that many years ago via their Colinear architecture as utilized in the PCM63 and PCM1704. To do so requires some non-trivial control logic, and DAC chips which are extremely well matched. It's much more likely that TeraDak has simply paralleled those TDA1543s, in which case the noise floor would be reduced, but the resolution would remain fixed at 16-bits.

My guess, and I emphasize, guess, is that the digital input receiver chip can accept 24-bits but is sending only the 16 most significant of them to the DAC chips. In which case the TeraDak would be 24-bit source compatible, but not deliver 24-bit signal conversion.

OK. It's like on eBay very few DAC sellers tell that though the DAC itself is 24 bit, and through SPDIF it can support 24 bits, with USB it can't (I am not talking about DACs with TE7022).

The 24 bits are supposed to be caught by the potential buyer's eyes, and hopefully for the seller he/she will make an erroneous buying decision.

qusp 15th June 2012 12:22 AM

Quote:

Originally Posted by nowhere (Post 3059901)
The 24 bits are supposed to be caught by the potential buyer's eyes, and hopefully for the seller he/she will make an erroneous buying decision.


correct, that about sums it up and many I would be surprised if they got 10-11 bits analogue

the idea behind them is that you stuff them full of huge film/foil/oil caps and/or transformers for the output and have to leave the lid off the case, always passive IV


All times are GMT. The time now is 01:43 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio


Content Relevant URLs by vBSEO 3.3.2