I want it to make it look a bit more fancy, so I added those LEDs; they indicate sources and phase.
The transformer will also lower the impedance seen by the chips. Being Iout, they really want to see 0 ohms.
In the balanced config with transformer, the Iout of each chip will see the parallel between the resistor and 1/2 of the reflected impedance on the primary. It´s quite easy to see they will be happier that way than if they were seeing the usual 1K or more.
And then there´s the filtering effect of the transformer which comes in handy with non oversampling.
Best,
Alex
In the balanced config with transformer, the Iout of each chip will see the parallel between the resistor and 1/2 of the reflected impedance on the primary. It´s quite easy to see they will be happier that way than if they were seeing the usual 1K or more.
And then there´s the filtering effect of the transformer which comes in handy with non oversampling.
Best,
Alex
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Hi, so you can indicate wether you´re in- or out-of-phase ? I guess
you´re using the 74atc86 chip for that. With relay?
And what circuit do you use for changing the source? I think the impedance
of the switch is important cause it affects 75ohm imp.
Greetings Ulf
I use TOCO toggle switch for source selecting, didn't observe any problems.
As to polarity switch, this is how it's implemented (to match my reversed XLR output wiring, for unbalanced signal, it will be the other way)
As to polarity switch, this is how it's implemented (to match my reversed XLR output wiring, for unbalanced signal, it will be the other way)
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Quite by accident I came across pictures of this system today, while browsing local audiophile club meetings: http://stereopal.com/HomeVisit/Marlen.htm
This is the older setup, from last October. You can still see there the TVC line stage I've built for him. The most recent picture in attachment. It's sort of a spy pic, that's why the quality isn't to my usual standards 😉
This is the system when we (me, Marlen and George from Audio Oasis) do all the critical listening comparisons. While all technical aspects of the design come from me, those two other guys always contribute to the final voicing of the device.
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And what do I use? My main DAC does not feature such fancy enclosure, I actually tried to avoid enclosure completely and ended up with a board mounted to a piece of spruce block with two small panels to secure connectors and another one on top, holding everything together. I quite like it this way. We compared fully enclosed DAC to this one, and didn't observe any major differences.
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My main transport is still TL0. Normally Shigaclone stands right beside (to play discs TL0 can't), but recently I was also using ML31.5 (testing before upcoming sale). The line stage is S&B TX102 (fully balanced), amps are F3 (mids/highs, passive crossover) and A75 (bass, crossed actively). The speakers were built in 1996 and I still find them attractive. The DAC sits in a back. All cables come from: BLUEBERRY HILL AUDIO-Manufacturer of high-end cables
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Hi Peter, thanks for this info. You may find the following useful:
Improving Your diyparadise Products
Improving Your diyparadise Products
Shunt regulator parts
I see that AD811 and LM285Z-2.5 are easily available from Digikey.
BSP129 is "on order" at MOUSER and due in August.
Just thought I would pass this along to any interested.
I see that AD811 and LM285Z-2.5 are easily available from Digikey.
BSP129 is "on order" at MOUSER and due in August.
Just thought I would pass this along to any interested.
bsp129 availability (for shunt regulator)
NEWARK says they are expecting stock next week and more in June, so not too big a deal.
NEWARK says they are expecting stock next week and more in June, so not too big a deal.
Hi Peter,
impresive as ussual. can you post the bom for the new schematic of the balance dac ?
thank you
deni
impresive as ussual. can you post the bom for the new schematic of the balance dac ?
thank you
deni
Unfortunately I don't have any BOM (never needed them for prototyping), however, it's relatively easy to figure out what parts are required following schematics and pics.
Peter, Having listened to a recently purchased Maganvox CDB 482 CD player with TDA1541 chip, I find myself interested i what this DAC is capable of. I have CS4398 OS DAC and find that it can sound digital at times with artifacts apparent in places. While it is not optimized, this seems likes a reasonable and simple implementation of a NOS DAC that would give me a pretty good idea of what to expect from this type of setup. I have two questions for you concerning the build. How do you match the chips? Would there be any advantage to adding I/V stage like D1? My current setup is Borberly balanced line-stage and Pass AJ's. I am also in process of gathering parts for F3 and noticed you use this amp. I have chosen it because i hope it pairs well with my MA 10.2 drivers. DO yo have any comments on the F3 sound?
I match the chips in a circuit; just swap them in and out until I get desired offset level, usually below 10mV.
I can't imagine any advantage in adding active I/V stage, unless of course your line stage can't work with passive I/V.
I like the sound of F3 very much, however, I'm not using any coupling caps at the output, those are replace by speaker's crossover capacitors. That also means that F3 works only as mids/highs amps in a biamp system.
I can't imagine any advantage in adding active I/V stage, unless of course your line stage can't work with passive I/V.
I like the sound of F3 very much, however, I'm not using any coupling caps at the output, those are replace by speaker's crossover capacitors. That also means that F3 works only as mids/highs amps in a biamp system.
HI Peter
I am using your Nos dac about 2 years now and I am very satisfied with the excelled sound
As all I think that it will be interesting to try your mods to go to the next level...
My Dac is fed by a Optima Red Top battery 12v/50Ah.
Do you think that I will need the Psu with the transformers or only the Regulators?
Your thoughts always count a lot!😉
Thank you Emmanouil
I am using your Nos dac about 2 years now and I am very satisfied with the excelled sound
As all I think that it will be interesting to try your mods to go to the next level...
My Dac is fed by a Optima Red Top battery 12v/50Ah.
Do you think that I will need the Psu with the transformers or only the Regulators?
Your thoughts always count a lot!😉
Thank you Emmanouil
