NOS Nakamichi DAC-101 2X TDA1541A-S1

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Hello! I have an old Nakamichi DAC-101 that i would like to run in NOS. The digital filter YM3414 (4 or 8times OS) split the I2s signal to one left and one right . The left signal comes to the dac TDA1541A-S1 like one "left normall" and one "left inverted". The right signal goes to it's dac in the same way as the left do. I need to find a device that can replace the digital filter. I only want the I2s signal to be splited in left and right without filtering or OS. I send the schematic for you people to see.
 

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The digital filter YM3414 (4 or 8times OS) split the I2s signal to one left and one right.

Unfortunately not. The signal bus between the receiver and the digital filter is not I2S, but a time multiplexed right justified format.

I only want the I2s signal to be split into left and right without filtering or OS.

There is no 'only' about it.

The YM3414 LSI currently in your DAC does another couple of jobs apart from oversampling and filtering. It de-multiplexes the data and changes the digital format. The glue logic after the filter LSI further alters the digital bus and improves its timing accuracy.

Replacing this functionality is a big job. I expect you've seen the threads on removing the SAA7220 filter in a lot of players, which is simple to do (this is because it only filters and oversamples, it doesn't change the digital bus format).

I am genuinely sorry to rain on your parade, but unless you have a lot of experience designing with glue logic, or preferably CPLDs, this is not a project I would even contemplate starting.
 
Unfortunately not. The signal bus between the receiver and the digital filter is not I2S, but a time multiplexed right justified format.



There is no 'only' about it.

The YM3414 LSI currently in your DAC does another couple of jobs apart from oversampling and filtering. It de-multiplexes the data and changes the digital format. The glue logic after the filter LSI further alters the digital bus and improves its timing accuracy.

Replacing this functionality is a big job. I expect you've seen the threads on removing the SAA7220 filter in a lot of players, which is simple to do (this is because it only filters and oversamples, it doesn't change the digital bus format).

I am genuinely sorry to rain on your parade, but unless you have a lot of experience designing with glue logic, or preferably CPLDs, this is not a project I would even contemplate starting.
Ok, i'm happy to get the answer so fast, and you are absolutly right... i'm not that experienced to "fix" with this kind of things, and yes i thaught it would be that easy just to find a spliter IC. My plans are now ruined, and i thinking about desolder the dac's. I really would like to hear these beauty's nos.
I allready have the S1 single crown in my digital amplifier (marantz PM-95) and i just love how it sounds. I have to try building the DIY-dac with these two chip's, or is it a waste of high performance dac's? Is the TDA1541A good enaught for this? Advices is thankfully recived.
 
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I can't read that rtf file and the online conversion tools either. So i don't know what is before the digital filter. In case it's I2S, i worked on a dac some time ago which did accept I2S and used two TDA1541's the way you want them to be used (so one DAC per channel). Allthough it's not perfect (see thread). No filter/oversampling.

It does require some glue logic (most important part is a shift register), so i think it's too complex. Thread is here on this forum.

But, i did see something similar once in a chinese DAC design being sold on the net. And they used a CPLD, so a one chip solution. Maybe that would suit you.

Personally i would replace the YM with a PMD100. Should be a much better filter and you can also use the TDA's differential. But this also requires some additional glue logic and going beyond the TDA's specs :rolleyes:
 
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So i don't know what is before the digital filter.

Neither do I (I'd put my money on a YM3623 or similar), I based my assessment on what the YM3414 accepts, which is very dissimilar to I2S.

I have to try building the DIY-dac with these two chip's, or is it a waste of high performance dac's?

Using the S1s for a DIY DAC is a good idea, and there are kits avalible for using two TDA1541As, but usually just in parallel, rather than the differential configuration your Nakamichi uses.

Another idea would be to build a new front end for the Nakamichi, but again this would be a lot of work.
 
I can't read that rtf file and the online conversion tools either. So i don't know what is before the digital filter. In case it's I2S, i worked on a dac some time ago which did accept I2S and used two TDA1541's the way you want them to be used (so one DAC per channel). Allthough it's not perfect (see thread). No filter/oversampling.

It does require some glue logic (most important part is a shift register), so i think it's too complex. Thread is here on this forum.

But, i did see something similar once in a chinese DAC design being sold on the net. And they used a CPLD, so a one chip solution. Maybe that would suit you.

Personally i would replace the YM with a PMD100. Should be a much better filter and you can also use the TDA's differential. But this also requires some additional glue logic and going beyond the TDA's specs :rolleyes:
The file i paste in the thread is a zipped word document. I send the file with the digital receiver. It's the pioneer PD0037. hope you can open this. Do you think it would improve the sound to run the digital filter in 4xOS ? What i heard, heavy OS make the high frequency's to fade a way,with less details. I maby forgot to say this is a dac for cars, but i thinking in build a new power source to run it with my stereo system. Or.. as i said before, take out the dac's and build something new. That would really be a shame when this is a good sounding dac. I bought it just for the two s1 single crown chip's, and to make it to NOS. I have to think some days...
 

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Why are you posting pictures within rich text format documents that are zipped? It's much easier for everyone trying to help you if you just post JPEGs.

The fact that the receiver is a PD0037 doesn't really change any of what I said before though.
 
Anyway, here are the schematics as JPEGs for this discussion:
 

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Why are you posting pictures within rich text format documents that are zipped? It's much easier for everyone trying to help you if you just post JPEGs.

The fact that the receiver is a PD0037 doesn't really change any of what I said before though.
I'm new to this, thats why. My original jpeg was more than 13 MB . And what i can see DIY accept jpeg with 195,3kB maximum, so i tryed something... By the way it seems that i have to forget about this NOS thing.:(
 
Hello! I have an old Nakamichi DAC-101 that i would like to run in NOS. The digital filter YM3414 (4 or 8times OS) split the I2s signal to one left and one right . The left signal comes to the dac TDA1541A-S1 like one "left normall" and one "left inverted". The right signal goes to it's dac in the same way as the left do. I need to find a device that can replace the digital filter. I only want the I2s signal to be splited in left and right without filtering or OS. I send the schematic for you people to see.

Dear Fragglan,

10 years after you, I would like to o exactly the same with my Nak DAC 101. Were you successful in your attempt? Got you the TDA1541 in non oversampling?

Pls, could yu send me the complete DAC 101 schematics? The attached zip file shows part of it only.

Thanl you very much!
 
Schematic Wanted

Hi Folks,
I also want to have full schematic of Nakamichi DAC-101
I'm not interested in NOS but I want to modify my DAC-101 analog part.
MODIFICATION NAKAMICHI DAC-101
I attached my current collections related DAC-101...


CyberPit
 

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