No, I am not selling kits.
I had some finished modules to spare and I wanted someone neutral to try and give his opinion about the DAC here in the forum.
(No, he did not have it for free, but I also did not get anywhere near enough for the time and money I spent on experimenting with it.)
It is much better if more people are prepared to take the time and trouble to explore different implementations.
This is how this forum flourishes.
Patrick
I had some finished modules to spare and I wanted someone neutral to try and give his opinion about the DAC here in the forum.
(No, he did not have it for free, but I also did not get anywhere near enough for the time and money I spent on experimenting with it.)
It is much better if more people are prepared to take the time and trouble to explore different implementations.
This is how this forum flourishes.
Patrick
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You contact one of the authorised distributors and see whether they would supply you the quantity you want. Then you make a request for the datasheet. They send you an NDA form to sign, and you get the datasheet afterwards as pdf.
Take some effort and a while, but it went through without too much problems. I asked a lot of technical questions afterwards, and they were all answered to my satisfaction.
Good luck,
Patrick
Take some effort and a while, but it went through without too much problems. I asked a lot of technical questions afterwards, and they were all answered to my satisfaction.
Good luck,
Patrick
I see that QLS are about to sell a version with integrated WM8740 DAC, headphone output and lithium battery: QA350--SD Card WAV High Fidelity Music Player
It is only a logic step to put a DAC to the QA, but to me this is not the right implementation.
For general use, it is way too large to compete with an MP3 player and there are many good ones on the market. For stand-alone audiophile, using a single (single-ended) power supply and lots of tantulum caps for dsPIC, DAC analog & digital, clock, and headamp IC is for me too much compromise.
If you want to use it as a source, adding a DAC module with separate supply is IMHO the right choice. And the easiest of the 3 modules I shown (TDA1543) requires very little effort (and cost) and still yields very respectable results.
Patrick
For general use, it is way too large to compete with an MP3 player and there are many good ones on the market. For stand-alone audiophile, using a single (single-ended) power supply and lots of tantulum caps for dsPIC, DAC analog & digital, clock, and headamp IC is for me too much compromise.
If you want to use it as a source, adding a DAC module with separate supply is IMHO the right choice. And the easiest of the 3 modules I shown (TDA1543) requires very little effort (and cost) and still yields very respectable results.
Patrick
I think that its a great idea for QLS to make a model with a DAC installed, however I think they have missed the point of their product. As you stated Patrick, its too big to be used as a truly portable player. people who buy these use them at home as a source. So the should have installed RCA jacks rather than a 3.5mm audio jack.
I commend QLS for going down this route. The audiophile community is in desperate need of a high quality low jitter HDD or flash card source.
I just wonder why none of the big name manufacturers have bothered to do this yet (except for Meridian - which is just too ridiculously expensive - so is out of the question)
The only thing that puts me off the idea of the QLS is that it only takes SD cards. Personally, I want to have all my music there at once, not have to copy files every time I want to listen to something different. - which defeats the comments made by QLS on their website where they write"In these days of hugely expensive utility bills, the electricity consumed in putting a computer to use for considerable periods just for music playback is also quite considerable as is wear and tear to the hardisks."
This cheap product from ebay would have been promising if the chip played WAV or FLAC, but unfortunately it only plays lossy formats.
Hard disk IDE MP3 Controller Board with LCD Display DIY - eBay, Other Brands, MP3 Players, Electronics. (end time 05-May-10 13:06:24 AEST)
I commend QLS for going down this route. The audiophile community is in desperate need of a high quality low jitter HDD or flash card source.
I just wonder why none of the big name manufacturers have bothered to do this yet (except for Meridian - which is just too ridiculously expensive - so is out of the question)
The only thing that puts me off the idea of the QLS is that it only takes SD cards. Personally, I want to have all my music there at once, not have to copy files every time I want to listen to something different. - which defeats the comments made by QLS on their website where they write"In these days of hugely expensive utility bills, the electricity consumed in putting a computer to use for considerable periods just for music playback is also quite considerable as is wear and tear to the hardisks."
This cheap product from ebay would have been promising if the chip played WAV or FLAC, but unfortunately it only plays lossy formats.
Hard disk IDE MP3 Controller Board with LCD Display DIY - eBay, Other Brands, MP3 Players, Electronics. (end time 05-May-10 13:06:24 AEST)
I have started a poll here..
http://www.diyaudio.com/forums/digi...les-want-stand-alone-high-end-hdd-source.html
Please vote if you have an opinion...
http://www.diyaudio.com/forums/digi...les-want-stand-alone-high-end-hdd-source.html
Please vote if you have an opinion...
Erin,
If you want convenience, I suggest you buy yourself a TEAC WAP2200. It supports all formats including FLAC and WAV. There are people on a German HiFi forum who hook this to a 1TB USB-HDD with God knows how many sub-directories and mixed formats all in one. I bought one for my sister. The DAC inside is pretty non-audiophile (a Wolfson codec) and has 1Vrms out and 'lytic coupling caps. So you want a SPDIF receiver plus a DAC. You can still use the ES9022 to reduce the jitter from the SPDIF.
The point of the QA550 is not convenience, BUT to drive the DAC AND a "non-spinning" (i.e. fully solid state) source with ONE common clock, so that both operates at exactly the same frequency and we do not need to have a PLL to correct for different timings of 2 clocks. This is e.g. the way I use the AK4396 with the QA550. They were both driven by a common oscillator near to the DAC. A non-spinning source is desirable because all spinning sources have reading errors which need correcting with the CD built-in error correction software.
This common clock idea was not used in the ES9022, because the 9022 has a different architecture to most DACs which allows it to re-time the incoming data. Hence it was used with an asynchronised clock of some 50MHz. That is how ESS works. I was sceptical myself, but the results speak for themselves.
Incidentally the WM8740 (as used in QA350) has single ended outputs (i.e. not ground referenced), so I guess either ('lytic) decoupling caps or extra opamps (headamps) are required at the voltage outputs of the DAC, as different from the ES9022.
Patrick
If you want convenience, I suggest you buy yourself a TEAC WAP2200. It supports all formats including FLAC and WAV. There are people on a German HiFi forum who hook this to a 1TB USB-HDD with God knows how many sub-directories and mixed formats all in one. I bought one for my sister. The DAC inside is pretty non-audiophile (a Wolfson codec) and has 1Vrms out and 'lytic coupling caps. So you want a SPDIF receiver plus a DAC. You can still use the ES9022 to reduce the jitter from the SPDIF.
The point of the QA550 is not convenience, BUT to drive the DAC AND a "non-spinning" (i.e. fully solid state) source with ONE common clock, so that both operates at exactly the same frequency and we do not need to have a PLL to correct for different timings of 2 clocks. This is e.g. the way I use the AK4396 with the QA550. They were both driven by a common oscillator near to the DAC. A non-spinning source is desirable because all spinning sources have reading errors which need correcting with the CD built-in error correction software.
This common clock idea was not used in the ES9022, because the 9022 has a different architecture to most DACs which allows it to re-time the incoming data. Hence it was used with an asynchronised clock of some 50MHz. That is how ESS works. I was sceptical myself, but the results speak for themselves.
Incidentally the WM8740 (as used in QA350) has single ended outputs (i.e. not ground referenced), so I guess either ('lytic) decoupling caps or extra opamps (headamps) are required at the voltage outputs of the DAC, as different from the ES9022.
Patrick
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Hi Patrick,
I know that CD transports can have errors but a HDD should not have reading errors otherwise my computer would not start up. Correct me if i'm wrong.
Also, the Teac unit is not audiophile quaility.
I am suggesting something that stores 1 or 2 TB of music in lossless format and is audiophile quality.
Erin,
There are many HDD players on the market. I know of quite a few from Yamaha combining CD transport with a built-in HDD.
What I suggested to you is one of the lowest cost, best sounding solution to suit your requirements.
One of our DIY Group members uses exactly the same configuration.
What is audiophile about the QA and not the TEAC? The oscon caps ?
Both are just uPs grapping data from a SPI storage device.
And I don't know of any audiophile uPs.
The TEAC has optical out, so its entire circuit can be isolated from the audio chain, especially if you use batteries and a 5V regulator.
It is jittery, but the ES9022 with an asychronous clock will take care of that.
Put them & a 1TB USB HDD in a box, and you have a one-box solution.
Personally, 16GB is enough for listening. So I stick to QA / Ultimate Source.
Patrick
There are many HDD players on the market. I know of quite a few from Yamaha combining CD transport with a built-in HDD.
What I suggested to you is one of the lowest cost, best sounding solution to suit your requirements.
One of our DIY Group members uses exactly the same configuration.
What is audiophile about the QA and not the TEAC? The oscon caps ?
Both are just uPs grapping data from a SPI storage device.
And I don't know of any audiophile uPs.
The TEAC has optical out, so its entire circuit can be isolated from the audio chain, especially if you use batteries and a 5V regulator.
It is jittery, but the ES9022 with an asychronous clock will take care of that.
Put them & a 1TB USB HDD in a box, and you have a one-box solution.
Personally, 16GB is enough for listening. So I stick to QA / Ultimate Source.
Patrick
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Hi Patrick,
thank you for the explainations but I guess my problem is that i want to use i2s into my TDA1541.
Apparently the TEAC cant do this.
You just said that the output of the TEAC is jittery. How do you know this?
If it is jittery, then it will not be sufficient for my needs, as I suspect that my CMP + cPlay computer will beat it.
on another point, why do you use the QA-550 rather than the TEAC, if the TEAC is so good?
thank you for the explainations but I guess my problem is that i want to use i2s into my TDA1541.
Apparently the TEAC cant do this.
You just said that the output of the TEAC is jittery. How do you know this?
If it is jittery, then it will not be sufficient for my needs, as I suspect that my CMP + cPlay computer will beat it.
on another point, why do you use the QA-550 rather than the TEAC, if the TEAC is so good?
I thought that the circuitry on the HDD takes care of error correction, so that the data delivered at the HDD interface is already error free. In addition, the error correcting codes on HDD's are different from those used on the CD's, so even if any errors needed correcting outside of the HDD, the CD built-in error correction software could not be used for this.
Or do I misunderstand something here?
The main disadvantage of HDD's is probably more their inherent noise and their need for a backup.
Kurt
Running i2s output from source to TDA1541 does give the same clock for Transport and DAC, BCLK. You only need a PLL in the digital reciver if using SPDIF. If what i read on the other thread is correct, the TEAC should output a 44.1khz BCLK, if playing 44.1Khz source material. So, source and DAC would be using one common clock. Correct me if im wrong.
Unfortunalty the TEAC outputs EIAJ rather than Philips format.
My suggestion was to use the Toslink from the TEAC to a CS8414 in slave mode (i.e. no extra 11.28MHz clock), and then ES9022 with its own 50MHz clock, and not to fiddle with the inside of the TEAC without schematics.
But there are many ways to Rome.
If you have to use your TDA1541 with I2S, then you need a different solution (and I have no suggestion for that).
The TEAC won't do.
Patrick
But there are many ways to Rome.
If you have to use your TDA1541 with I2S, then you need a different solution (and I have no suggestion for that).
The TEAC won't do.
Patrick
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There is already a Version 7 :
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Patrick
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Patrick