AudioSector-chip amp kits, dacs, chassis

[Peter Daniel]

Ideas like that are always welcome here

 

[woodturner-fran]

Heres that pic - hopefully it will be of some use to someone.

An externally hosted image should be here but it was not working when we last tested it.

Fran

 

[JBdV]

Hello Peter, are you still considering a FireWire version of your DAC?

Maybe I can provide some info and I want a FireWire DAC ;-)

 

[Peter Daniel]

It depends on your info

 

[karma]

heat transfer

peter some time back you used ceramic insulaters to transfer heat
from mosfet to heatsinc. i cant remember the name of em.
any idea what the name is or where i can pick em up?


thanks


cheers

 

[Peter Daniel]

Those were aluminum oxide pads, available from Mouser: http://ca.mouser.com/Search/ProductDetail.aspx?qs=2v7q0MSBcBMwt5GBytMENg==

 

[Telstar]

Hello Peter, are you still considering a FireWire version of your DAC?

Maybe I can provide some info and I want a FireWire DAC ;-)

The biggest issue with firewire, is that to be used with windows or linux, it requires drivers to be written.

Can you do that?

 

[2A3SET]

1543 DAC improvement

-ECDESIGNS- posted a new 1543 design without using the VREF,

http://www.diyaudio.com/forums/showthread.php?s=&threadid=79452&perpage=25&pagenumber=115

Looks interesting and easy to implement.

Quoted from that thread,

Same applies for Vref (pin7) if this pin is connected to anything, sound quality degrades dramatically. This is caused by ground or power supply noise polluting both bias current source and DAC output current, then it's over. So never ever connect this pin!

I use 680 Ohm passive I/V resistors, this gives enough signal to directly drive my power amps (100K input impedance). Since I only use one TDA1543, I need a reference voltage for these I/V resistors. This is also required to use the actual DAC output current (that flows to GND).

Mains power supplies are too polluted for this, and a "floating" supply is required. So I simply used 2 penlight alkaline batteries (I needed one for the master clock anyway). Current consumption (TDA1543 powered-up) equals 2 x 1.15mA = 2.3mA. When the player is shut-down, the TDA1543 no longer draws any bias current, so the battery can simply stay connected. The master clock only consumes a few hundred nano amperes when shut down, and even less when operating. So the batteries should last a long time.

I am using TDA1543 with 680 ... 900 Ohm passive I/V resistor and alkaline 3 ... 3.8V reference voltage (like in the SD-player diagram I posted).

This gives 0.0023 * 680 = 1.56Vpp ... 0.0023 * 900 = 2.07Vpp from a single TDA1543 chip without using the Vref pin.

 

[jeff mai]

I'm using this PC Engines Alix as a transport for Peter's DAC:

http://www.pcengines.ch/alix2d2.htm

I highly recommend this PC if you know Linux or are curious about learning it. It consumes around 5 watts using the Linux app Music Player Daemon to play music located on a file server through an attached USB sound card or DAC. It does not have a lot of processing power for upsampling, but why would you do that if you have Peter's NON-OS DAC?

There is a location for a second USB header on-board. I was thinking you could hardwire the USB DAC connection to this header and run the DAC and PC off the same PSU in the same enclosure (the Alix requires only a single 7 - 18VDC supply.)

 

[jeff mai]

Should anyone want to try the Alix, there is a guide to setting it up here:

http://cheap-silent-usb-linux-music-server.blogspot.com/

Not my blog, but I did add a few comments to it on my set up experience.

 

[AlanElsdon]

Balanced to Unbalanced

Peter,

I am wanting to run a balanced supply into my Patek-style amplifier; I have had a look at the Edcor transformers (as you use for going the other way) - would these Edcor M2M600/150 transformers be suitable?
http://www.edcorusa.com/products/ShowProduct.aspx?ID=24

Regards

Alan

 

[samoloko]

Re: 1543 DAC improvement

-ECDESIGNS- posted a new 1543 design without using the VREF,

http://www.diyaudio.com/forums/showthread.php?s=&threadid=79452&perpage=25&pagenumber=115

Looks interesting and easy to implement.

Quoted from that thread,

Same applies for Vref (pin7) if this pin is connected to anything, sound quality degrades dramatically. This is caused by ground or power supply noise polluting both bias current source and DAC output current, then it's over. So never ever connect this pin!

I use 680 Ohm passive I/V resistors, this gives enough signal to directly drive my power amps (100K input impedance). Since I only use one TDA1543, I need a reference voltage for these I/V resistors. This is also required to use the actual DAC output current (that flows to GND).

Mains power supplies are too polluted for this, and a "floating" supply is required. So I simply used 2 penlight alkaline batteries (I needed one for the master clock anyway). Current consumption (TDA1543 powered-up) equals 2 x 1.15mA = 2.3mA. When the player is shut-down, the TDA1543 no longer draws any bias current, so the battery can simply stay connected. The master clock only consumes a few hundred nano amperes when shut down, and even less when operating. So the batteries should last a long time.

I am using TDA1543 with 680 ... 900 Ohm passive I/V resistor and alkaline 3 ... 3.8V reference voltage (like in the SD-player diagram I posted).

This gives 0.0023 * 680 = 1.56Vpp ... 0.0023 * 900 = 2.07Vpp from a single TDA1543 chip without using the Vref pin.

Peter

have you tried this
your comment

 

[Peter Daniel]

Re: Re: 1543 DAC improvement

I am wanting to run a balanced supply into my Patek-style amplifier; I have had a look at the Edcor transformers (as you use for going the other way) - would these Edcor M2M600/150 transformers be suitable?
http://www.edcorusa.com/products/ShowProduct.aspx?ID=24

I have no experience with those transformers whatsoever, but if your source can drive them, the amp won't have problem either.

have you tried this
your comment

I've seen it, but didn't try it yet. In general, I'm usually scheptical of claims like that.

 

[JBdV]

Regarding a FireWire Dac it might be worth looking into for example cheap Lacie PC speakers with FireWire.

 

[cyxg]

Here's a more detailed view, not all components are installed yet.

Hi, Peter

I got one plitron 97w transformer. It has 18V*2 and 12V*3. Can I use it build your buffer?

Thanks

 

[AndrewT]

you can draw a continuous 300mAdc from any or all of the 12V windings.
Similarly you can draw a continuous 370mA from either or both of the 18V windings.
This will easily supply a few buffers and headphone amplifiers.

 

[cyxg]

I buy copper from Metal Supermarkets.

any body knows?
is there any Metal Supermarkets in AUSTRALIA?

 

[cyxg]

...The sound acquired completely new dimension, resolution is improved, but what most important, the melody lines are much better pronounced now. Each instrument and each sound exists in it's own space and has now complete freedom of expression. Small details, that were not noticed previously, are more obvious now. ...

Hi,peter
i finished my buffer got from you.
i running it over 50 hours. sound like you said.

but, i feel the middle range sound density less than to connect USBDAC directly.

 

[cyxg]

... However I HIGHLY suggest doing ones you listen too. The bennifits are are more than worth it. The poor CDs you have may all of a sudden be worth listening too.

http://www.audiocircle.com I invite you Peter to have a look. Squeeze Box, SB, Slimware, and Foobar2000 have taken over.
...

hi,peter

i also got USBDAC from you. it's very good sound and convenient to play WAV or APE by Foobar2000.

i strongly recommend you to rip CDs.

 

[samoloko]

are there any better decoupling cap than pana FC which can be substitute to Black Gate
has anybody compared rubycon ZA/ZL, nichicon, pana FM