Topic: Oade modSBM-1 discussion

[Todd R]

Well, yes and no.  The SBM1 could be great at 16 bits, but have too much inherent noise as part of its design to get anything useful at 24 bits.  That is, the increased 8 bits of resolution would just be essentially random due to the noise, and not capturing the true audio signal.  That would explain why a box could be good at 16 bits, but not worth it to be expanded to 24 bits.  But if those additional 8 bits are only capturing noise, what would be the point of dithering and noise-shaping from 24 bits to 16 bits?

At any rate, it doesn't sound like the SBM1 is going to be a candidate for a 24-bit A/D, even if the mods could be easily done.

[Kindguy]

I'm so glad this thread is here. I've always been confused about the mods. But never searched it out till I wanted one.

I just picked up a SBM-1 (Oade ADC-24 SBM-LINE modification). spelled out just like the box in the pic shown earlier.

[scb]

not sure if this was posted yet

http://www.oade.com/cgi-bin/miva?Forum/technology/showmsg.mv+message=3116

he responded to marc to say it was a new op amp, not adc chip...

[marc0789]

not sure if this was posted yet

http://www.oade.com/cgi-bin/miva?Forum/technology/showmsg.mv+message=3116

he responded to marc to say it was a new op amp, not adc chip...

blast from da past.

[scb]

damn right.  back in the "who the fuck is this blackpete asshole?" days 

[marc0789]

damn right.  back in the "who the fuck is this blackpete asshole?" days 

times have changed, but the asshole has not.

[L Ron Hoover]

Damn, that was only three years ago? Seems like a lifetime.

[marc0789]

Daryan Lenz on soldering, circa 02:

I ordered a sla last night, I have a charger, and would just like to
solder some sort of wiring from the battery to the 3 pin, mini xlr.
I am trying to avoid cutting my da-p1 power supply, so if anyone has
a suggestion on what to use as far as wire from the battery to the
3-pin xlr female interconnect, I would really appreciate it.

Daryan

 

[macdaddy]

so if it is an opamp, where does the "24bit" mod come from..?

[marc0789]

so if it is an opamp, where does the "24bit" mod come from..?

good question.....perhaps the mod unit *does* sample at 24 bits? which is pretty irrelevant I guess if it dithers to 16 anyway.

[nickgregory]

either that or marketing language

[Brian Skalinder]

good question.....perhaps the mod unit *does* sample at 24 bits? which is pretty irrelevant I guess if it dithers to 16 anyway.

Per the manual, the stock SBM-1 ADC creates a 24-bit signal and then employs the SBM process to dither down to 16-bit for output.

And as quoted by Mic D earlier, a bit more detail on this process in a post from the Oade archives:

Snagged from the oade archives...

This was how the Sony technical support rep I just got off the phone
with explains the SBM A/D used in all their products carrying that
identifier in simple terms. This is using simplified explanations,
so computer geeks, please overlook the obvious generalizations.

" The SBM initially quantitizes the analog signal into 24bit data and
then through a noise shaping filter which is the core of the SBM
process. First it analyzes the entire waveform and identifies bytes
of noise information it finds in the audible bandwidth that it
captures until it reaches 4 bits worth of this information. This 4
bits of information is then cut out completely. The remaining 20
bits of data are then reintegrated, or dithered, into the 16 bit
word length."

[marc0789]

good question.....perhaps the mod unit *does* sample at 24 bits? which is pretty irrelevant I guess if it dithers to 16 anyway.

Per the manual, the stock SBM-1 ADC creates a 24-bit signal and then employs the SBM process to dither down to 16-bit for output.

And as quoted by Mic D earlier, a bit more detail on this process in a post from the Oade archives:

Snagged from the oade archives...

This was how the Sony technical support rep I just got off the phone
with explains the SBM A/D used in all their products carrying that
identifier in simple terms. This is using simplified explanations,
so computer geeks, please overlook the obvious generalizations.

" The SBM initially quantitizes the analog signal into 24bit data and
then through a noise shaping filter which is the core of the SBM
process. First it analyzes the entire waveform and identifies bytes
of noise information it finds in the audible bandwidth that it
captures until it reaches 4 bits worth of this information. This 4
bits of information is then cut out completely. The remaining 20
bits of data are then reintegrated, or dithered, into the 16 bit
word length."

then I guess that was a bit deceptive to market the thing as "Oade ADC-24" as my box from the Oades claims.

[Kindguy]

good question.....perhaps the mod unit *does* sample at 24 bits? which is pretty irrelevant I guess if it dithers to 16 anyway.

Per the manual, the stock SBM-1 ADC creates a 24-bit signal and then employs the SBM process to dither down to 16-bit for output.

And as quoted by Mic D earlier, a bit more detail on this process in a post from the Oade archives:

Snagged from the oade archives...

This was how the Sony technical support rep I just got off the phone
with explains the SBM A/D used in all their products carrying that
identifier in simple terms. This is using simplified explanations,
so computer geeks, please overlook the obvious generalizations.

" The SBM initially quantitizes the analog signal into 24bit data and
then through a noise shaping filter which is the core of the SBM
process. First it analyzes the entire waveform and identifies bytes
of noise information it finds in the audible bandwidth that it
captures until it reaches 4 bits worth of this information. This 4
bits of information is then cut out completely. The remaining 20
bits of data are then reintegrated, or dithered, into the 16 bit
word length."

then I guess that was a bit deceptive to market the thing as "Oade ADC-24" as my box from the Oades claims.

Then why are the ADC chips changed out & the part # scratched off?

[Brian Skalinder]

Then why are the ADC chips changed out & the part # scratched off?

Dunno, ask Doug.