There is a single-bit sigma-delta audio DAC in large-volume production that I designed myself, so I don't need to rely on what's in the datasheet. It's part of a larger system-on-chip. Unfortunately I'm not at liberty to give you more information about it.
That is why I chose to purchase the completed assembly from Arcam, figured they would have circumvented that with the 5102, but good to know for certain about the load. Thanks for the solid info!
And I have long suspected that to be the case with any v out dac chip per the original question in this thread. My wm8741 works wonders with both an I/V stage along with a buffer.
Most of the high end ones don't have ground centered outputs with charge pumps. Even the Cirrus parts with charge pump have no problem and can drive 600 ohms or even lower. So, no, it's not a problem with all voltage output chips at all.
Also, WM8741 has a voltage output so I don't know why you would use an I/V converter.
How nice it is to have someone from TI here..
Thank you for the useful information PaulFrost
I will try the PCM5102 DAC..
(a very non- DIY post) This DAC has two AUDIO OUT ports, one is Balanced, the other one is UNBALANCED. For driving an amplifier/amplified speakers just set the volume to maximum (or set it to any level you choose) More info: - SHENZHEN DAHAO TECHNOLOGY CO., LTD - Review and Measurements of Sabaj Da3 Dac compared to Dragonfly Black | Audio Science Review (ASR) Forum
My day long listening device use a pcm5102 (powered from usb to boot). Honestly, I'd be hard pressed to describe a difference compared to much more expensive DAC I've tried or built.
Still, its specs aren't that great. The wm8741 does quite a bit better and AKM's offerings a lot better on that front if you really want to try the best chipsets.
Surprising.
What DAC product is it?
Is it the FX Audio FX-01, or something else?
And btw, what do you mean by "to boot"?
("powered from usb to boot")
I sometimes see the WM8740 being mentioned,
sometimes the WM8741,
and sometimes the WM8742, like in Cambridge Audio's "DacMagic 100" (a 200$ product).
Their product pages in cirrus.com don't provide distinct info on how to choose each
WM8740 | Cirrus Logic
WM8741 | Cirrus Logic
WM8742 | Cirrus Logic
But it seems that the WM8740 is different from the other 2: WM8741 and WM8742,
especially in the power consumption (80-160mW in the first, vs 407mW in the last 2)
Also in dynamic range: 117 dB versus 125 dB. Not that that makes any difference at normal listening levels, the noise floor will be quite inaudible in either case, but it certainly makes a difference for the power needed to reach such dynamic range figures.
A rule of thumb is that with a similar architecture and supply voltage, the power dissipation of the analogue/mixed-signal part increases with a factor of 10^(1/10) for each extra dB of dynamic range. The actual ratio of power dissipations is smaller than that, which could mean that the digital part is not negligible or that the rule of thumb is too simple:
10^(8/10) ~= 6.3096
407 mW/79.2 mW ~= 5.1389
407 mW/160 mW ~= 2.5438
Remarkably, the THD+N is actually better for the WM8740: -104 dB versus -100 dB (which also doesn't matter much).
A rule of thumb is that with a similar architecture and supply voltage, the power dissipation of the analogue/mixed-signal part increases with a factor of 10^(1/10) for each extra dB of dynamic range. The actual ratio of power dissipations is smaller than that, which could mean that the digital part is not negligible or that the rule of thumb is too simple:
10^(8/10) ~= 6.3096
407 mW/79.2 mW ~= 5.1389
407 mW/160 mW ~= 2.5438
Remarkably, the THD+N is actually better for the WM8740: -104 dB versus -100 dB (which also doesn't matter much).
No, it's a design from my own. See here
"To boot" means "as well". Just a way to say that the power source (usb) isn't the greatest, just like the pcm5102 isn't the greatest chipset. Which doesn't prevent it to sound quite good to me.
The FX-01 has a pretty decent reputation on French audio board btw. Considering its low price, it's hard to see how you could go wrong with it.
DPH, you're completely incorrect..
6 months ago I purchased several DACs, and found one that I really like, it's TDA1387 based.
Now, after several months of not trying any more DACs, I decided I want to try more..
My curiosity makes me want to try more DACs.
Hopefully after this second series, I will feel I had enough of different DACs.
Oh..
The term "boot", along with "USB", usually means something completely different
Terrific..
I ordered it yesterday..
Hopefully it will arrive soon.
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Fair enough, it seemed like a continuing conversation. Hopefully this round is more fruitful.
I am looking forward to hearing of your listening impressions in comparison to your TDA1387 based DAC!
The first round was also fruitful.Hopefully this round is more fruitful.
The TDA1387 DAC is so good that after I heard it, I purchased another unit, to have as backup..
For anyone interested, it's this:
L1387DAC 4X Quad TDA1387 fever USB decoder beyond the TDA1543 | eBay
Amazing value you get, for 21$...
Of course
Hi spaceman5,
As the toppic is about I/V things, could you tell us please (you need to look at inside the box) what are the oap used in your tda1387 dac please in order to give us some food on why it is found to sound so good according your tastes ?
I looked at the picture, one can see 4 x tda1387, some excelent capacitors as thegreen Sanyo or LXJ Nippon-Chemi-con, two looking like some Philips (blue axial ones), MKT blue from vishays or CDE (?) and also less good tantalum or ceramic yellow drop capas towards the RCAs output.
But impossible to see what are after the 4 dac chips halas after the two blue MKT caps!
It would please people here as Abraxalito perhaps to have a picture of your whole TDA1387 pcb..
Halas there are so much factors that your original question will not drive you towards a decision as a dac is not just about its dac chip but also as already said about the layout and external parts arounds. So your own conclusions could be biased by this fact, your budget, the rest of your hifi (what are the speakers, amps, room, etc)...
All the dac chips discussed here are good and have pro and cons but halas it doesn' tell you about their quality or defaults when listening to them as you don't listen to a dac chip alone as you already know. Always these damned trade off we have all to deal with...
Be carefull if you are on a budget to balance the purchase of several little dac vs only one but from a very good quality you could also buy second hand... There are many 1500 to 2000 usd brand new dacs which will be very good enough to let you think you migh tneed to change all the others devices around, speakers, etc.
Sorry about the disgress, think it's not off topic and that helps and oh... shoot a beautifull picture of your tda1387 pcb for us please
regards
As the toppic is about I/V things, could you tell us please (you need to look at inside the box) what are the oap used in your tda1387 dac please in order to give us some food on why it is found to sound so good according your tastes ?
I looked at the picture, one can see 4 x tda1387, some excelent capacitors as thegreen Sanyo or LXJ Nippon-Chemi-con, two looking like some Philips (blue axial ones), MKT blue from vishays or CDE (?) and also less good tantalum or ceramic yellow drop capas towards the RCAs output.
But impossible to see what are after the 4 dac chips halas after the two blue MKT caps!
It would please people here as Abraxalito perhaps to have a picture of your whole TDA1387 pcb.
.Halas there are so much factors that your original question will not drive you towards a decision as a dac is not just about its dac chip but also as already said about the layout and external parts arounds. So your own conclusions could be biased by this fact, your budget, the rest of your hifi (what are the speakers, amps, room, etc)...
All the dac chips discussed here are good and have pro and cons but halas it doesn' tell you about their quality or defaults when listening to them as you don't listen to a dac chip alone as you already know. Always these damned trade off we have all to deal with...
Be carefull if you are on a budget to balance the purchase of several little dac vs only one but from a very good quality you could also buy second hand... There are many 1500 to 2000 usd brand new dacs which will be very good enough to let you think you migh tneed to change all the others devices around, speakers, etc.
Sorry about the disgress, think it's not off topic and that helps and oh... shoot a beautifull picture of your tda1387 pcb for us please
regards
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... oups, sorry, i saw the others pictures of your link... seems the I/V is made 100% passive with resistors and there is no oap buffer : so what you like here is, for a part of it, the combo of a particular resistor (here surface mount) with a particular cap used for the passive I/V operation. the more tda1387 chips the more current at output so the less the value resistor which is important in that direct typology, you can notice also TDA1387 with 8 dac chips... But a standalone one could suffice if the further stage is well designed : you should try Abraxalito tda1387 dac but you may need basic diy to add it an usb to I2S board (that is cheap).
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Hi diyiggy
Thank you very much for this useful information.
I tried to find that post now in order to quote it here, but couldn't find it.. :/
I assume this is not a prevalent method of doing the I/V?
Because people usually put much more than just a resistor..
Regarding Abraxalito - he also has this DAC..
He's the one who recommended me about this DAC chip,
and he modded this DAC also..
Mine is not modded.
Actually I am not on a budget, I just enjoy trying different ones, as long as their price is reasonable and not hundreds or thousands of $.
Thank you very much for this useful information.
Yes, someone wrote about it here a few weeks ago, regarding this DAC product.
I tried to find that post now in order to quote it here, but couldn't find it.. :/
It definitely might be a part of it.
I assume this is not a prevalent method of doing the I/V?
Because people usually put much more than just a resistor..
Regarding Abraxalito - he also has this DAC..
He's the one who recommended me about this DAC chip,
and he modded this DAC also..
Mine is not modded.
Amazing identification of components, from such low resolution images
That's a great tip.
Actually I am not on a budget, I just enjoy trying different ones, as long as their price is reasonable and not hundreds or thousands of $.
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