Hi,
Is anyone running their TDA1543 at 9V? I'm currently have mine at 8V and was wondering if 9V is worth trying. There is the odd mention that Lab 47 use 9V....
Cheers,
Anthony
Is anyone running their TDA1543 at 9V? I'm currently have mine at 8V and was wondering if 9V is worth trying. There is the odd mention that Lab 47 use 9V....
Cheers,
Anthony
Just sacrifice one for the sake of "science", they're so cheap 😎
Got one on 9.05V for a few hundred hours now, still alive
Got one on 9.05V for a few hundred hours now, still alive
I have a 7809 regulator before it, so it must be running on 9V 🙂.
And for several weeks.
Anyone tried more TDA1543s (on top of each other) from a direct I2S connection to see if it is worth?
Miguel
And for several weeks.
Anyone tried more TDA1543s (on top of each other) from a direct I2S connection to see if it is worth?
Miguel
Never trust 78xx completely, especially when they're the older types. The newer ones are fairly precise but I'd measure what voltage it has at the output to be sure.
I remember 7818 and 7918 that produced from 17 to nearly 20 V ( yes, with decoupling caps ).
Jean Paul, how can you know if it's an old one or not?
I think it's the same where you live, small local electronic stores have parts since years. And I rerely saw a manufacturing date on an IC (especially not on a reg)
I think it's the same where you live, small local electronic stores have parts since years. And I rerely saw a manufacturing date on an IC (especially not on a reg)
So I guess I was lucky, as mine gave 9.00VDC on my DMM. I decoupled it with 1uF film on both sides.
The real question (for me anyway) is how to decouple the DAC in order to get no noise or hum...
Miguel
The real question (for me anyway) is how to decouple the DAC in order to get no noise or hum...
Miguel
Bricolo said:
There are almost always datecodes on active components. Besides that old IC's aren't a problem as long as you check the voltage ( which you always should do in any circumstance as making errors is a human virtue ).
Hum isn't a question of decoupling but more a bad ground layout or wrong wiring the thing. There are various sources on the web how to proper wire audio-gear so I won't go into that again.
Keyword is "ground loop".
Anyone tried more TDA1543s (on top of each other) from a direct I2S connection to see if it is worth?
Miguel
Yes, have a look at the other 1543 thread. It is described in detail by happy ears.......
Miguel
Yes, have a look at the other 1543 thread. It is described in detail by happy ears.......
passive power supply
Anthony,
Here's one to try. It's what I did and it works great with my 4x 1543 DAC, which runs at about 300mA.
Get a 12V SLA battery, about 5Ah. I got a 15R 15W surplus rheostat, and added a 10R 10W resistor for 10R-25R adjustment. Put this in series with the battery and adjust until the voltage is where you like it. You'll have about 20R of resistance. Since the battery is <1 ohm impedance, the effective impedance of the powersupply (before caps) is about 20R, which is pretty good. I follow this with 4x 220uF 16V cerafines, for a total of 880uF of capacitance, bypassed with 0.1uF 50V film caps.
This allows you to adjust voltage at will, and also gets that IC voltage regulator out of the PS.
Anthony,
Here's one to try. It's what I did and it works great with my 4x 1543 DAC, which runs at about 300mA.
Get a 12V SLA battery, about 5Ah. I got a 15R 15W surplus rheostat, and added a 10R 10W resistor for 10R-25R adjustment. Put this in series with the battery and adjust until the voltage is where you like it. You'll have about 20R of resistance. Since the battery is <1 ohm impedance, the effective impedance of the powersupply (before caps) is about 20R, which is pretty good. I follow this with 4x 220uF 16V cerafines, for a total of 880uF of capacitance, bypassed with 0.1uF 50V film caps.
This allows you to adjust voltage at will, and also gets that IC voltage regulator out of the PS.
Hi,
Last night I tried 9V and it was a noticeably different. The DAC become more precise and less warm. I can see why some people like high volts and some like low volts. At 9V it seems to have greater control and with that better sound stage. The chip runs slight warm but nothing to worry too much about. On 8V it was pretty cool.
The question I now have who here has their TDA1543 running on low volts is using active I/V? From what I have heard so far if you use passive I/V then you need higher volts.
Also you need more the 12V supply. The 7809 sounds MUCH MUCH better with a supply of 18-24V. And yes it needs a heat sink.
While I had my soldering iron out and after listen to the DAC at 9V I replaced all the cheap metal film resistors in the output with some Rikens 1/2w. Again very interesting change. I love carbon films in valve amps they bring a smooth muscality to the table but here the change was one of greater clarity and less warmth or should I say less fuzz around the image.
I'll let this burn in and then make my mind up.
Cheers,
Anthony
Last night I tried 9V and it was a noticeably different. The DAC become more precise and less warm. I can see why some people like high volts and some like low volts. At 9V it seems to have greater control and with that better sound stage. The chip runs slight warm but nothing to worry too much about. On 8V it was pretty cool.
The question I now have who here has their TDA1543 running on low volts is using active I/V? From what I have heard so far if you use passive I/V then you need higher volts.
Also you need more the 12V supply. The 7809 sounds MUCH MUCH better with a supply of 18-24V. And yes it needs a heat sink.
While I had my soldering iron out and after listen to the DAC at 9V I replaced all the cheap metal film resistors in the output with some Rikens 1/2w. Again very interesting change. I love carbon films in valve amps they bring a smooth muscality to the table but here the change was one of greater clarity and less warmth or should I say less fuzz around the image.
I'll let this burn in and then make my mind up.
Cheers,
Anthony
dddac,
can you tell what resistors did you use on your 3 x TDA1543 DAC? I mean for reference and output. I want to add 2 more to my 1xTDA1543 setup to see what it brings, but dont know how to change these resistors. Presently I use 1.2k for ref and 2.3k for output. Any way to check optimum values without a scope?
jean-paul,
I certainly know that ground loops are a problem, but after making a ground plane with copper foil I guess no loop can be there... But it still hummssss.
Miguel
can you tell what resistors did you use on your 3 x TDA1543 DAC? I mean for reference and output. I want to add 2 more to my 1xTDA1543 setup to see what it brings, but dont know how to change these resistors. Presently I use 1.2k for ref and 2.3k for output. Any way to check optimum values without a scope?
jean-paul,
I certainly know that ground loops are a problem, but after making a ground plane with copper foil I guess no loop can be there... But it still hummssss.
Miguel
Miguel, a ground plane has not much to do with having a ground loop. There is a possibility that the ground plane is connected wrong for example. When the PSU is OK there is almost no other explanation than that you have a ground loop.
Check your ground wiring as well. Never had any hum with TDA DACs I built.
Check your ground wiring as well. Never had any hum with TDA DACs I built.
Some interesting reading on ground loops and ground planes
http://www.analog.com/UploadedFiles...70227201355514263225653595342524731AN-345.pdf
http://www.analog.com/UploadedFiles...70227201355514263225653595342524731AN-345.pdf
I have to connect the ground plane to:
- PSU 0V (I use the pins of a big cap on the cdp PSU)
- and to chassis
Is this rigth or am I missing something here?
- PSU 0V (I use the pins of a big cap on the cdp PSU)
- and to chassis
Is this rigth or am I missing something here?
I dont have a digital camera🙄.
I have the following:
ground plane
__________________________________________
| | | |
To PSU 7809 and dac and output
and chassis caps caps on dac resistors
Hope this is understandable.
Miguel
Hum etc.
Miguel ,
dddac offers explanation on "how to calculate" optimum Rref. and Rload value on his site ... initialy he start looking for "best" value to use with a single 1543 chip . namely 1K35 for Rref. and 2K2 for Rload . accordingly at 8.5 VDC supply !!
However in your suggested case ( 5 dac chips in total ) if I'm right ? you can simply divide this value by #5 ... so Rref close to 270 Ohm and Rload close at 440 Ohm .
Of course you can use a pot too , in that case you can adjust one and other untill you find your "magic spot" .... but Doede did a great job/test on his single chip version .... completely agree with his findings here !
About your hum-gost , that might be a tougher job to determine ..
Are you sure you have enough regulation from your 78xx ?? etc etc . any excessive voltage drop across the regulator after stacking dac chips perhaps .. good luck
Happy Ears
miguel2 said:dddac,
can you tell what resistors did you use on your 3 x TDA1543 DAC? I mean for reference and output. I want to add 2 more to my 1xTDA1543 setup to see what it brings, but dont know how to change these resistors. Presently I use 1.2k for ref and 2.3k for output. Any way to check optimum values without a scope?
jean-paul,
I certainly know that ground loops are a problem, but after making a ground plane with copper foil I guess no loop can be there... But it still hummssss.
Miguel
Miguel ,
dddac offers explanation on "how to calculate" optimum Rref. and Rload value on his site ... initialy he start looking for "best" value to use with a single 1543 chip . namely 1K35 for Rref. and 2K2 for Rload . accordingly at 8.5 VDC supply !!
However in your suggested case ( 5 dac chips in total ) if I'm right ? you can simply divide this value by #5 ... so Rref close to 270 Ohm and Rload close at 440 Ohm .
Of course you can use a pot too , in that case you can adjust one and other untill you find your "magic spot" .... but Doede did a great job/test on his single chip version .... completely agree with his findings here !
About your hum-gost , that might be a tougher job to determine ..
Are you sure you have enough regulation from your 78xx ?? etc etc . any excessive voltage drop across the regulator after stacking dac chips perhaps .. good luck
Happy Ears
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