D1 I/V with TDA 1541A

[smario]

Hello !

I'd like to put D1 I/V stage on DAC with TDA 1541. I've read somewhere that this could be done. Could somebody post (or send me) a schematic of I/V stage and how to connect it to TDA 1541? Any listening impressions?

Thanks in advance !

 

[santi]

Hi smario
You can connect D1 to TDA1541A without any problem. Don't forgot to remove TDA1541A's R I/V.

The sound was very nice (for my ears).

 

[smario]

Coud you post or mail me schematic od D1 and how it is connected to TDA1541?

I made http://www.diyaudio.com/forums/attachment.php?s=&postid=578104&stamp=1108695002


Is it ok to connect Ina(b) directy to Aol (Aor) on TDA1541A ? I trimmed Ina to 0 V and after connection to Aol nothing happened.

 

[santi]

I used the same schematic as you.

Is it ok to connect Ina(b) directy to Aol (Aor) on TDA1541A ? I trimmed Ina to 0 V and after connection to Aol nothing happened.

Yes, It's OK.

Does your TDA1541A work OK without D1 I/V?

 

[smario]

Does your TDA1541A work OK without D1 I/V?

How could I check, if it works ok without I/V? All voltages (+5V,-5V,-15V) are ok.

 

[santi]

Use R I/V, 47-150 Ohms connect AOL, AOR to ground then connect AOL, AOR to your amp. The signal was very low, just turn your volumn more than usual.

 

[smario]

I'll try this resistors as soon as I come home and report the results next morning.

Thanks !

 

[smario]

I put 82 ohm resistors and connected the amp. The result is nothing. Input reciever is locked on signal from the cd-transport but nothing is out from the dac. I'll have to dismantle the entire dac and check it.

Does anybody have have any idea what could be wrong?

 

[poolorpond]

Did you read the data sheet to determine the correct I/V resistor? I think the 1543 uses 1k. If the chips are similar, 82r would be a little low and might not make enough voltage. You also might have to set the current on the dac with another resistor to Aground. Sorry if this is not helpful, I don't have the data sheet in front of me.

 

[santi]

smario
Does you have "reclock circuit" between digital receiver and dac?
If yes, try to bypass the reclock.

 

[smario]

I don't have the reclock circut. I tried to make DAC as simple as possible. Afterwards I planed to put the reclock circut. I'd try to borrow an osciloscope.

Shematic could be seen here:
http://www.pedjarogic.com/1541a/pdf/rev1_1b_sch.pdf

I did not make the I/V stage like this one on the schematic, but I made D1 I/V that should be connected directly to the Aol (Aor) pins on TDA1541A.

 

[hifimaker]

Has anyone used 2 TDA 1541A's per channel for balanced output?

-David

 

[smario]

I made some mesurements and there are the results. On WS line is 2,82MHz, and on BCK line is 44.08KHz.

That is all ok. Sound is still missing.

Any suggestions ????

 

[smario]

I fixed my dac.
D1 I/V works but another problem came up. At full level (0 dB) positive swing is 2.3V but negative is clipped at -1V. When music is played, this clipping can be heard, and it can burn the tweeters in speakers.

Any suggestions how to fix this ?

 

[smario]

Fixed everything !
DAC with D1 I/V sings like a bird

 

[poolorpond]

I was also thinking about the D1 output stage but was impressed with passive I/V so I thought that i might wait.. . . Ok waited long enough.

If the dac chip requires a reference voltage (for bias) of 2/3 Vcc, roughly 2.5 volts, do you need to keep the same bias circuit that already exists on the dac board? Or, do you bias the D1 with its potentiometers at 2.5 and connect to the dac chip?

Any thoughts would be helpful.

 

[skseah]

Hi Smario,
So what was the fault ? I am thinking of building a balance output D1 I/V stage ? Would appreciate your experience.

 

[smario]

There was a fault on pcb. Shematic works, no problem.

 

[flyboi]

Hi guys!

What is the output impedance of this D1 IV? Thanks!


Regards,

Eddy.

 

[Hattori Hanzo]

Has anyone used 2 TDA 1541A's per channel for balanced output?

Yes I did. I used the same method to invert the data as it is done in the original D-1. Apart from the different DAC and PS everything else between the digital receiver and analog out was just copy/paste. Works great...