okay I'll try 10uF or 22uF later.
I'm now focus on the supply rail .
It's 33ohm in series and 100uF(or 47uF) for decoupling at philips design.
It's a low pass filter here.
I've studied the datasheet of lme49720
And the recommendation is to two shunt decoupling cap 10uF 0.1uF to ground.
"No" resistor on supply rail.
So.....I can just remove the 33ohm? or I need to replace it from a bead or inductor?
I'm now focus on the supply rail .
It's 33ohm in series and 100uF(or 47uF) for decoupling at philips design.
It's a low pass filter here.
I've studied the datasheet of lme49720
And the recommendation is to two shunt decoupling cap 10uF 0.1uF to ground.
"No" resistor on supply rail.
So.....I can just remove the 33ohm? or I need to replace it from a bead or inductor?
i check out 2 x TDA1541A for the simultaneous format from my TDA1540 14bit dac to 16bit. I have one jumper on CPLD to choose 14 or 16 bits. In balanced mode, one chip per ch, data+ and data- inputs. Very simple from Riv to the inter-stage trafo, bal to se.
Just to sniff is it working or not.
And it is working, from few songs I listened partially, very very nice indeed. And up to 192KHz NOS probably because of 6Mb speed. (Against the TDA1540 up to 384KHz 12Mb speed from datasheet)
cheers
Just to sniff is it working or not.
And it is working, from few songs I listened partially, very very nice indeed. And up to 192KHz NOS probably because of 6Mb speed. (Against the TDA1540 up to 384KHz 12Mb speed from datasheet)cheers
Funny!
I too just finished a working setup of two TDA1541a in simultanious mode and balanced configuration.
I had two old Red Baron boards, that I stripped for almost everything. I then used 100uF for DEM decoupling and 1uF and 12k for the DEM osc.
I used 150 Ohm as passive I/V resistor and 5Kohm trimmer to +5V to set V out to 0 V DC . This is also important for the distortion figure. I tried the old 2SK216 I/V, but that was not good enough.
As i2s to simultanious mode I used Ian Canada´s I2StoPCM module.
Powersupply is LCR prefilter and Salas shunt regulators.
I have, for a long time now, preferred a setup consisting of TDA1543 with an in house constructed I/V converter (and LifePo4 battery supply) to any of the TDA1541a I made, based on the dynamics and live feeling the 1543 was capable of. Even in some cases the natural timbre and tone of instruments in good orchestral recordings, even though I was well aware of the small roughness and lack of ultimate resolution the 1543 had.
Now this configuration with TDA1541a in simultanious mode , fed with stopped clock digital signal and in balanced mode, changed my preferences. Now the dynamics are back and the little bit synthetic and polite character is gone. And the refinement and resolution is still there, well - even better, I think.
I too just finished a working setup of two TDA1541a in simultanious mode and balanced configuration.
I had two old Red Baron boards, that I stripped for almost everything. I then used 100uF for DEM decoupling and 1uF and 12k for the DEM osc.
I used 150 Ohm as passive I/V resistor and 5Kohm trimmer to +5V to set V out to 0 V DC . This is also important for the distortion figure. I tried the old 2SK216 I/V, but that was not good enough.
As i2s to simultanious mode I used Ian Canada´s I2StoPCM module.
Powersupply is LCR prefilter and Salas shunt regulators.
I have, for a long time now, preferred a setup consisting of TDA1543 with an in house constructed I/V converter (and LifePo4 battery supply) to any of the TDA1541a I made, based on the dynamics and live feeling the 1543 was capable of. Even in some cases the natural timbre and tone of instruments in good orchestral recordings, even though I was well aware of the small roughness and lack of ultimate resolution the 1543 had.
Now this configuration with TDA1541a in simultanious mode , fed with stopped clock digital signal and in balanced mode, changed my preferences. Now the dynamics are back and the little bit synthetic and polite character is gone. And the refinement and resolution is still there, well - even better, I think.
That's good to hear.
My balanced DACs are close to completion and will also be using IanCanada's I2S board.
I have 3 Dac builds on the go: dual AD1865, dual TDA1541A and quad AD1862, using transformer I/V feeding the balanced inputs of the Doug Self/Carl Huff preamp. (then Quad 405-2 and Martin Logan Aeons)
Having once owned an Audio Note Dac1.1 which used an AD1865 in NOS mode, I liked the sound character but the 1541 in NOS just bettered it.
I decided to try Pcbway.com.cn for the AD1865 pcbs as their prices were very good (£32 including shipping for 5)
The larger AD1862 pcbs are from Eurocircuits and cost about £12 each but I will use Pcbway in future assuming the boards are good.
I found an excellent rack mounting CD player to use as a transport. Its a Denon DN-C110 costing £35 on Ebay. The build quality is much better than the usual consumer CD players and dedicated transports are outside my budget. The cd mechanism is a Sony KSS240a which seems very sturdy.
There is room inside for the I2S pcb and the connector pin outs from the CD processor to the existing dac pcb are labelled so it was easy to find the I2S signals.
The rack design matches the preamp and dac enclosures.
I want to add, that the TDA 1543 DAC had miniDSP usb streamer feeding Ian Canada`s FIFO - USB isolator - Dual clock.
The TDA1541a only had miniDSP streamer and I2StoPCM in front. I want to make a 4 channel DAC to be able to let Audiolense make a digital crossover to future subs and this calls for 4 channel DAC. My Ian Canada Fifo only supports 2 channels...
The TDA1541a only had miniDSP streamer and I2StoPCM in front. I want to make a 4 channel DAC to be able to let Audiolense make a digital crossover to future subs and this calls for 4 channel DAC. My Ian Canada Fifo only supports 2 channels...
Do you use 2 6K8 resistors. If I am recalling it right, ECDesigns recommended only to use 1 12 Kohm?
Did not follow his 12k recommendation. Just left the 2 6k8 resistors from his earlier design in place. Added a 1uf cap to the existing 100pf I had in place previously. RyanJ was the trail blazer on this one. I'll defer to his comment.
Maybe 1 x 12K is for different values of dem C 100uF. And 2 x 6.8K are for standard values of dem C network?
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from short listening sessions my opinion is the that TDA1541A working much better With Simultaneous format then I2S format? It is starting versinon very simple, I did not aplly yet 2mA current injections at the analog outputs, and free running dem. (I wil not apply 100uF dem Cs because I dont want to wait 10min to charge...)
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from short listening sessions my opinion is the that TDA1541A working much better With Simultaneous format then I2S format? It is starting versinon very simple, I did not aplly yet 2mA current injections at the analog outputs, and free running dem. (I wil not apply 100uF dem Cs because I dont want to wait 10min to charge...)
it is not about dem R. Something else is. tda1541A in my set up playing nos 192KHz. probably some mismatch in digital line input format?
I dont´t think it is a mismatch in format , as wlowes uses excatly the same digital format board (Ian Canada I2S2PCM) as I do. The only difference is , I use it in balanced mode with two TDA1541a.
Wlowes: Do you use coax cables between Ian´s board and the TDA1541a?
Have you linked pin 16 of the 1541s together?
When I was using two in quasi balanced operation (with the standard dem config) I did get a lot of noise until I linked the pins.
Worth a shot?
No such luck, but thanks for the suggestion. Made no difference. Actually I have no digital noise , except if I go over 96Khz.
I think I have to clean up the rather crude first setup. All the digital lines are non shielded and not terminated in any way, just directly connected fro Ian´s board to the two TDA1541a boards.
Yes, cables with ufl connectors connecting RyanJ's 1541a pcb to Ian's. 4" if I recall correctly. I use RyanJ's 1rst gen pcb which has no signal attenuation at input. And it is crystal clear at 192 with and without the 100uF DEM cap mod. With the mod everything is improved btw. Better separation in 3D making all music more 3D.
Aha, yes.. Then could be the coon?
I am using dual differential mode one chip per ch. (mono block config separate power supply's) and digital isolators before the dac chips. connections are not coaxial but simple flat cable snap in type with 10pin connector...
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Listened a bit more yesterday, and sounding better than I2S mode. Very natural, easy, good kick, soft highs, and no digital harshness - for me much of the importance.
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with curent inj. of 2mA per ch. measured offset at the Rivs is 1-3mV. Today I will add free running dem
I don't know how this was not captured.
The question was;
"Do somebody know if I can move the output 10K shunt Resistor(3645 3644 ) or not?
Maybe it's related to the impedance matching with the AMP
My AMP is JC Verdier 220de(6L6G)(with 16W output and 50K VR input) "
Yes it is completely related with the impedance of the amplifier. 10k in parallel with 50k. My advice was to change the 100uF to 2.2uF and the 10k to 1M, and therefore 2.2uF is working into 1M//50k = 47.6k load.
So, try the calcs with 2.2uF into ~47.6k. -3dB at 1.52Hz. Also, the 2.2 unit can be of much higher quality than ANY 100uF unit. Being as it is so far toward the front of the system, it will make a noticeable difference.
Happy days!!
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