"Reference" TDA1541A DAC with I2S-BUS architecture

[dvb projekt]

Bargain Sale

Here you could order my ready build Red Baron DAC test module with
-ecdesigns- MK7 onboard I/V stage:

Main Parts

- TX2575 0,1% I/V resistors ($18.80/pair solo)
- PRP resistors
- Sanyo OS-CON SEPC capacitors

and the needed DC Reference module:

Main Parts

- Vishay Bulk Metal Foil 1280G trimmers ($30.70/pair solo)
- Sanyo OS-CON SEPC capacitors

for the special price of

Complete $99

including
Worldwide shipping and paypal fee









If you are interested, please send me a PM.

[dvb projekt]

Originally Posted by dvb-projekt

Bargain Sale

Here you could order my ready build Red Baron DAC test module with
-ecdesigns- MK7 onboard I/V stage:

Main Parts

- TX2575 0,1% I/V resistors ($18.80/pair solo)
- PRP resistors
- Sanyo OS-CON SEPC capacitors

and the needed DC Reference module:

Main Parts

- Vishay Bulk Metal Foil 1280G trimmers ($30.70/pair solo)
- Sanyo OS-CON SEPC capacitors

for the special price of

Complete $99

including
Worldwide shipping and paypal fee









If you are interested, please send me a PM.

Sold!

[martinn]

Hi all,

wanted to share a finished Red Baron I am planning to use in an old philips cd player, but unfortunately one of the five 100R capacitors in the mail today was 27.4 k... so I can say it's almost assembled I will have to make a trip to a local electronics shop before connecting and powering up the board.

Oliver: I've noticed the 106C inductor is on some posts oriented one or the other way. In post #766 top picture it's how I have it, on the same post two pictures below it's rotated. Is the 106C sticker sometimes rotated? Plus end is pointing towards +5V and ground is up, right?

Can't wait to finally hear it. I hope it sounds as good as it looks

Thanks,
Martin

[martinn]

all componets in place

[dvb projekt]

Originally Posted by martinn

Hi all,

wanted to share a finished Red Baron I am planning to use in an old philips cd player, but unfortunately one of the five 100R capacitors in the mail today was 27.4 k... so I can say it's almost assembled I will have to make a trip to a local electronics shop before connecting and powering up the board.

Oliver: I've noticed the 106C inductor is on some posts oriented one or the other way. In post #766 top picture it's how I have it, on the same post two pictures below it's rotated. Is the 106C sticker sometimes rotated? Plus end is pointing towards +5V and ground is up, right?

Can't wait to finally hear it. I hope it sounds as good as it looks

Thanks,
Martin

Hi Martin,

very nice soldered

In the specifications of the inductor are no informations about an orientation mark. Normally you could solder it in both directions.

I hope you didn´t forgot to flip the MOSFET Source and Drain Pin!

Cheers,
Oliver

[martinn]

Originally Posted by dvb-projekt

Hi Martin,

very nice soldered

In the specifications of the inductor are no informations about an orientation mark. Normally you could solder it in both directions.

I hope you didn´t forgot to flip the MOSFET Source and Drain Pin!

Cheers,
Oliver

Hi Oliver,

thanks for the nice comment and all the help! I took my time soldering and checking if all the contacts are ok. All the parts arrived last Friday except for the capacitors and I could not wait without doing sth.

The inductor came with a longer and shorter wire, so I thought orientation might play a role. Found something on inductor orientation and frequency response.

Mosfets drain and source are flipped.

Rechecked the orientation for the quad input gates (pointing right, ground legs are connected to ground).

I think all is set for the test run in the evening

Best,
Martin

[martinn]

Guys I will need some help (again) .

Hooked up all the cables, powered up... no smoke. So far so good. Checked the voltages, V digital-analog GND is 0, +15 V is 14.84 V, -5V is -5.59V, +5V is 4.79V. Adjusted the trimmers to 0V offset left and right channels with respect to digital GND and then the same on the DC board with respect to the new left right grounds... connected to the amp, pressed play and... no sound, it's dead silent.

First thing I've checked if the cables supplying FS, clock, data have contact and they are fine.

Then I've checked if the data format is right. Pin 27 OB/TWC is connected to VDD +5V, which means the data format is the same as on my cd player.

Checked if I've connected the output / input wrong.

TDA1541a side:
pin 1 = LS/ WS
pin 2 = BCK
pin 3 = DATA (time multiplexed mode??)

goes to Red Baron I2S input:
pin 1 = BCK
pin 2 = LS/ WS
pin 3 = DATA

I guess this is fine.

and now it's time for more

I've looked at the SAA7220 filter and TDA1541a datasheets, but I don't seem to find the filter would need anything leading back from the dac i.e. the filter does not know the dac is not there.

This is as far as I came. Have to get an used osciloscope somewhere, but maybe it's something simple I've overlooked For anyone wanting to take a look there are two images attached; the cd board side and an overlay of cd to Red Baron.

Thanks,
Martin

[dvb projekt]

Originally Posted by martinn

Guys I will need some help (again) .

Hooked up all the cables, powered up... no smoke. So far so good. Checked the voltages, V digital-analog GND is 0, +15 V is 14.84 V, -5V is -5.59V, +5V is 4.79V. Adjusted the trimmers to 0V offset left and right channels with respect to digital GND and then the same on the DC board with respect to the new left right grounds... connected to the amp, pressed play and... no sound, it's dead silent.

First thing I've checked if the cables supplying FS, clock, data have contact and they are fine.

Then I've checked if the data format is right. Pin 27 OB/TWC is connected to VDD +5V, which means the data format is the same as on my cd player.

Checked if I've connected the output / input wrong.

TDA1541a side:
pin 1 = LS/ WS
pin 2 = BCK
pin 3 = DATA (time multiplexed mode??)

goes to Red Baron I2S input:
pin 1 = BCK
pin 2 = LS/ WS
pin 3 = DATA

I guess this is fine.

and now it's time for more

I've looked at the SAA7220 filter and TDA1541a datasheets, but I don't seem to find the filter would need anything leading back from the dac i.e. the filter does not know the dac is not there.

This is as far as I came. Have to get an used osciloscope somewhere, but maybe it's something simple I've overlooked For anyone wanting to take a look there are two images attached; the cd board side and an overlay of cd to Red Baron.

Thanks,
Martin

Hi Martin,

have you done the NOS Mod. to get the SAA7220 out of the circuit?

Servus,
Oliver

[martinn]

Originally Posted by dvb-projekt

Hi Martin,

have you done the NOS Mod. to get the SAA7220 out of the circuit?

Servus,
Oliver

Good morning Oliver,

Yes, I've done the nos mod some time ago. The 7220 is physically still there just the out LS/WS, BCK, data are not connected to the dac, but there is a thin wire connecting these three from filter input directly to the dac as done here:
lampizator_DIY NOS Non Over Sampling modification

"""
1. Locate the "LEG 1" on the underside of 1541 and 7220 chips
2. on 7220 cut both traces as close as possible to legs 15 and 16
3. on 1541 cut trace as close as pos on leg 1
4. using a thin wire connect the 1541 and 7220 : leg 1 to 1, 2 to 2, and 3 to 3.
5. connect the 7220 leg 23 to the other chip - the de-modulator chip 7210 leg 11. In case of the Marantz 40/50/60 - there is a newer chip - the 7310 - a square black spider with 44 legs - 11 on each side of the square. The mute is in this case leg 18 (which looks like floating)
6. sit back and listen.
In case of the SAA7220 and SAA7210 chips - if the mute trick does not work, you must float (isolate) the leg 11 on SAA7210 before connecting it to SAA7220P 's leg 23.
"""

aaah, to the Red Baron I2S BCK I should connect the subcode clock at 2,82 Mhz from pin 6 on 7220 instead of connecting pin 2 at 11,29 Mhz xtal which is what I did. Thanks a lot! Have to run (skiing), people are already becoming impatient.... tomorrow evening I am back.

[martinn]

It works

The problem were the five 100 ohm resistors. Seems the BCK signal from my cd-player is weak and got attenuated below a minimum signal threshold. Someone else on the thread had a similar problem and this started my poking with a wire and resistor bypassing. With all five or four resistors in series = no sound. Three resistors in series = weak sound and lots of noise and clicking. With two resistors it works wonderfully.

The sound:
On the cd-player I already had larger mkp bypass capacitors for the dac and nos mod and I did not expect such an improvement. It really stunned me how much more transparent and liquid the sound is. After the cd nos mod, the sound was very analog or brutal like and now it's very smooth, more natural and extremely pleasant to listen to. Haven't done extensive testing yet, but I am already very impressed.... Thanks Oliver for all the help and the amazing Red Baron!!!

and now it's time to enjoy a bit... before the clock upgrade
Martin