Drive NOS AD1865/62,PCM1704/02/63,TDA1541 from FIFO: Universal I2S-PCM driver board

Some good news: PCM1704, TDA1541A confirmed working at 384KHz driven by PCM board

I made a fixture and did some test with success yesterday. I confirmed both PCM1704 and TDA1541A NOS DAC can work perfectly at 384KHz driven by I2S to PCM convertor board.

System configuration was:

1. PureMusic with 384KHz real time up-sampling and memory play
2. Amereo384 USB audio interface with I2S isolator
3. FIFO KIT with Si570 clock board running at 98.3040 MHz (can also use Dual XO clock board with 45.xxx/49.xxx MHz XOs)
4. I2S to PCM convertor board
5. PCM1704 or TDA1541A NOS DAC

PCM1704 can work at both half-speed and full-speed mode. Software based real time up-sampling filter should be better than hardware based DIF chips because of the 64bit calculation and algorithm.

TDA1541A sounds very nice at 384KHz, but could only work at half-speed mode. Though in this case, according to the datasheet, it’s already over clocked.

I2S to PCM convertor board can work with Amereo USB audio interface without FIFO KIT for sure, but can only go up to 192KHz because of the low frequency on board MCLK. I hope they can upgrade it to the 45.xxx/49.xxx MHz version later on.

I upgraded WaveIO to new firmware which comes with 384KHz support, and I did some test with same configuration. But I got problem with it. WaveIO plays noise at 384Khz on both PCM1704 and TDA1541A. But no problem at 352KHz. I tried back and forth a couple of time still cannot fix it. It might be a software compatible issue with pure music. Just hope it can be solved soon.

I attached some pictures blow. Please find the picture name for details. I2S to PCM board could also be stacked on top or underneath the clock board to save space.

Ian
 

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Hi Ian,

I have not yet read the whole manual in detail. A quick skim read it looks good! A big achievement to get it all written down so concisely, there is a huge number of options on these boards!

I did notice that points 8 and 9 on the Application Notes & Tips page are missing test point numbers 'TPX' is presumably a place-holder for you to place the respective numbers. Looking at the pic of the top of the PCB I'm thinking maybe the 3pin regulator doesn't have TPX designations unless they're on the underside? These perhaps are now best shown as 3.3Vout, GND and VIN.


Chris
 
Hey Ian,

Concur- Great Job!

I am struggling to see the u.fl inputs that are mentioned in the table on the board unless that are on the underside? There were a couple other u.fl I couldn't see that we're mentioned, will check again later
Really tops effort, look forward to getting this in play!

Thanks again,

Drew.
 
Hi Ian and others,

This looks really good and I look forward to implementing it between FIFO/Dual XO and TDA1541A.

I'd like to ask: if someone wanted to set up TDA1541A at 352.8kHz I can see that using the Dual XO board in double speed mode and with U1 at 45.1584MHz it would run at 128*Fs and expect all to be ok. However, using the same double speed mode and same clock at U1 would have 44.1kHz playback at 1024*Fs.

Would this change at all using the I2S > PCM board, and if not, any idea how well TDA1541A would handle 44.1kHz playback at 1024*Fs - using the same clock in the same position and in the same mode.

The other question I have is, assuming WaveIO issues are sorted and it plays 384kHz correctly, is there any problem with using the Dual XO board with U1 at single speed mode (TP3-TP4) with 22.5792MHz clock for 44.1kHz at 512*Fs and U2 at double speed mode (TP6-TP7) with 49.1520MHz clock for 384kHz at 128*Fs.

Thank you,
Shane
 
Thanks Shane, hope I can answer your questions

Hi Ian and others,

This looks really good and I look forward to implementing it between FIFO/Dual XO and TDA1541A.

I'd like to ask: if someone wanted to set up TDA1541A at 352.8kHz I can see that using the Dual XO board in double speed mode and with U1 at 45.1584MHz it would run at 128*Fs and expect all to be ok. However, using the same double speed mode and same clock at U1 would have 44.1kHz playback at 1024*Fs.

Would this change at all using the I2S > PCM board, and if not, any idea how well TDA1541A would handle 44.1kHz playback at 1024*Fs - using the same clock in the same position and in the same mode.

When we talk about the 1024*Fs, it means the relation ship between MCLK frequency and Fs of an I2S signal. If using an I2S to PCM board, the situation gonna be totally different. There is no any MCLK at all after the PCM board, the D/A conversion will be controlled only by LE (LLLR), which is always running at 1*Fs NOS mode . I this case, You can not run your TDA1541A at I2S mode any more, it has to be jumped to offset binary mode(PCM mode). A 45.xxxMHz XO on dual xo clock board can cover from 44.1 to 352 KHz. FIFO does not need a MCLK as input, so, for the I2S input, FIFO doesn't care about the *Fs.

The other question I have is, assuming WaveIO issues are sorted and it plays 384kHz correctly, is there any problem with using the Dual XO board with U1 at single speed mode (TP3-TP4) with 22.5792MHz clock for 44.1kHz at 512*Fs and U2 at double speed mode (TP6-TP7) with 49.1520MHz clock for 384kHz at 128*Fs.

Yes, that's no any problem. With FIFO, dual xo clock board and PCM board, 22.xxxMHz XO can handle 44.1, 88.2, 176.4KHz, while the 49.xxx MHz XO can handle 48, 96, 192 and 384KHz. It has already be confirmed by Combo384 USB.
 
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Hi Ian,

I have not yet read the whole manual in detail. A quick skim read it looks good! A big achievement to get it all written down so concisely, there is a huge number of options on these boards!

I did notice that points 8 and 9 on the Application Notes & Tips page are missing test point numbers 'TPX' is presumably a place-holder for you to place the respective numbers. Looking at the pic of the top of the PCB I'm thinking maybe the 3pin regulator doesn't have TPX designations unless they're on the underside? These perhaps are now best shown as 3.3Vout, GND and VIN.


Chris

Thank you so much Chris, you found a bug! Yes, it should be VIN, GND and 3.3V VOUT. Will be changed in V1.0

You won debug award of this year :D.

Have a good night

Ian
 
Hey Ian,

Concur- Great Job!

I am struggling to see the u.fl inputs that are mentioned in the table on the board unless that are on the underside? There were a couple other u.fl I couldn't see that we're mentioned, will check again later
Really tops effort, look forward to getting this in play!

Thanks again,

Drew.

Hi Drew,

Another good point. Yes, they are on the bottom side of PCB. I'll discuss with vzs to see if we should include the layout of the other side into users manual.

Thank you so much!

vzs:

What do you think?

Ian
 
Hey Ian,

Just so I understand, with the 45/49 clocks, if fed a 16/24bit 44/88/176/352 or 48/96/192/384 it will simply work into a TDA1541 automagically using the offset binary mode. This is what I grasp from your answers above. Need to reread the manual too!
Looking forward to this! Get to finally put the 45/49 cryteks that qusp added to an order for me!

Thanks Ian!

Drew
 
Yes, that's no any problem. With FIFO, dual xo clock board and PCM board, 22.xxxMHz XO can handle 44.1, 88.2, 176.4KHz, while the 49.xxx MHz XO can handle 48, 96, 192 and 384KHz. It has already be confirmed by Combo384 USB.

Thanks for your reply, Ian - It answers my questions very well.

It seems then that 45.xxx + 49.xxx clocks should cover all bases, as Drew suggests below, without any penalty to 1541A operating with the PCM board.

Now, to wait patiently.. :)

Regards,
Shane
 
Hi Ian,

Got the converter board and did a quick test - it works nicely with AD1865 in both full-speed and half-speed modes!

The unfamiliar board among the pics is the music source Wandboard on top of an WD USB HDD. It will be stuffed into the DAC box as soon as I have time to do it.

Regards,
Zsolt
 

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Hi Ian,

Got the converter board and did a quick test - it works nicely with AD1865 in both full-speed and half-speed modes!

The unfamiliar board among the pics is the music source Wandboard on top of an WD USB HDD. It will be stuffed into the DAC box as soon as I have time to do it.

Regards,
Zsolt

Thank you for your good news. Looks very nice. What is the maximum Fs your AD1865 is going?

I didn't see your AD1865 :D.

I think I'll buy a Wandboard board. I can source it from mouser in Canada.

Ian
 
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Thank you for your good news. Looks very nice. What is the maximum Fs your AD1865 is going?

I didn't see your AD1865 .
Thanks! I'm hiding my AD1865 :)

Forgot to mention... maximum Fs is 384KHz with full-speed mode.
Since it's overclocked with full-speed mode at 352.8|384KHz I'm using the half-speed setting - don't hear differences but will do some tests later on and maybe switch back to full-speed.

Zsolt
 
Thanks! I'm hiding my AD1865 :)

Forgot to mention... maximum Fs is 384KHz with full-speed mode.
Since it's overclocked with full-speed mode at 352.8|384KHz I'm using the half-speed setting - don't hear differences but will do some tests later on and maybe switch back to full-speed.

Zsolt

Good to know that. You confirmed AD1865, I confirmed PCM1704 and TAD1541A. It seems with this I2S to PCM board, all NOS DACs we tested can work up to 384KHz at NOS mode . That's really a good news.

Ian
 
Thanks! I'm hiding my AD1865 :)

Forgot to mention... maximum Fs is 384KHz with full-speed mode.
Since it's overclocked with full-speed mode at 352.8|384KHz I'm using the half-speed setting - don't hear differences but will do some tests later on and maybe switch back to full-speed.

Zsolt

Hi Zsolt,

I'm very interested in your AD1865 board. The concept is like a core board, with keeping anything else such as digital front end, IV, power supply external, the core board could become a standard part.

Each DAC can have its own core board to reduce the cost and complexity, for example AD1865 core board, TDA1541 core board and so on. With same size and same interface, they can share a same platform. Change DAC will be as easy as change a XO.

I like this idea :).

Ian