DIYHiFi.org

I saw this product listed here - http://www.ttvj.com/index.php?main_page ... ts_id=1289

I noticed one section is basically lifted from some article by Ryohei Kusunoki here - http://www.sakurasystems.com/articles/Kusunoki.html ('The Sound of Non-Oversampling')

Information is kind of sparse on this thing. I'm just wondering if someone more familiar with this type of technology than I am may be able to shed some light on it. I found some datasheets that were apparently about the FN1242A, but they're in japanese and I simply cannot read it. Maybe I just don't understand it, either; it just looks like they're showing a slow roll-off filter that has better impulse response and less passband ripple than some other unnamed filter.

edit - spelled Kusunoki's name wrong X_X

It looks like NOS but that FN1242A is, so they say, 24bit/192Khz. Looks like delta-sigma but probably without digital filter or accepts an external DF.
They talk about a DSP. Probably this is not a NOS implementation, but a slow rolloff DF?

Hey, this one is cool:
"Custom parts made exclusively for Luxman; the paint used on the resisitors on the tiny stripes, that denote is value & tolerance have been chosen for the sonic qualaties."

Wasn't it Pioneer that made the first universal player, in the japanese market? Must have been around year 2000...

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Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein

Yeah, it looked like a slow-rolloff DF, which is already claimed to accomplish some of these supposedly, as far as I recall.

I'm not familiar with the FN1242A part; I did find a datasheet about *a* part with this part number that is a dac, and yeah it's a delta-sigma part. The app note schematic, provided I'm reading it correctly, makes it look as though it's an SCF output dac (e.g. v-out), which is kind of

The THD+N spec for SACD matches that of the datasheet (0.002%), so seems like it's a good chance it's the same part.

Interesting part...Initially I tought it's a custom AKM or something...but then I tried google and came up with the translated web page from the manufacturer's website: Nigata Seimitsu. I hope the link works.
There you can find the datasheet, demoboard, schematic...etc - in japanese of course Aparently you can even order some of these DACs directly from them.

I can't read the datasheet very well but it looks like maybe it's saying the THD is measured w/ 20KHz bandwidth, in which case 0.002% isn't all that hot for a 1KHz THD+N since that wouldn't be including what is probably fairly high out of band noise. Not to say that THD+N is the be-all end all, but it seems like it wouldn't speak well for IM/DIM performance considering how these d-s parts tend to behave, especially (it seems? maybe I haven't tested enough) those with the SCF output...

Oh well, might be worth trying if someone is feeling adventurous enough to make a board for it (not me! )

I'm personally wondering how they "restore" everything that got cut off above 22KHz during mastering.

(if it's an alias of 0-22.05KHz, no, that doesn't count.)

Pioneer claimed they did, with the "Legato Link" system.

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Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein

LUXMAN DA-07 The first commercial first Fluency DAC

US Patent 6411238 Digital to analogue converter with step voltage generator for smoothing analog output

Kazuo Toraichi uses a similar technique in image processing toraichi.pdf

Regards
James

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