How does the 896 mk3 handle analog output at 192kHz?

[AndreaT]

Dear Folks,

anybody knows exactly how the MOTU 896 mk3 Hybrid handles the Analog Output at 193kHz when the source streams and the system sampling clock is set 2x or 4x lower rate?

Anybody knows exactly if it does 2x and 4x automatic oversampling or not?
I asked this to the technical support, but no final reply received so far.

Herein below is what I could get after one month of "discussion":

Details

Do you confirm that all the Analog Output operate anyway at 24bit 192 kHz regardless of the input/system sampling frequency?
Thank you. Regards, Andrea

Responses


Added byNicoleon2012/02/02 12:18:22 US/Eastern

State change from 'Unread' to 'In progress'
Hello Andrea,
Yes, the 896 mk3 Hybrids' Analog Outputs all are capable of outputting at 24 bits/ 192kHz.

Hope this helps,

.Nicole
MOTU


Added byAndreaon2012/02/03 06:02:38 US/Eastern

Dear Nicole, your reply is not clear for me.

My question is: Does the Analog Output always work at 192kHz 24bit regardless of the System Sampling Frequency set?

In other words, if my source is a CD Player connected via SPDIF, so having digital input running at 16bit 44.1kHz, does the Analog Output run at 24bit 192kHz doing an internal own oversampling and conversion?

Thanks and regards,
Andrea


Added byNicoleon2012/02/08 13:28:43 US/Eastern

Hi Andrea,
If you are running SPDIF in at 16/44.1k, your MOTU unit should be clocked to 16/44.1k, otherwise you may run into clocking problems within your (re)recordings...

Perhaps if I understood what you were trying to do with the device, I might better be able to assist you with this particular task or application...?

Thanks very much,

.Nicole
MOTU


Added byAndreaon2012/02/09 06:39:08 US/Eastern

Dear Nicole, I just want to know if the ADC and the DAC are working independently in the 896 mk3 and if the DACs of the Analog Output 1 to 8 and Mains are always running at 192kHz regardless of the source material sampling frequency.

Many products have such a kind of independent operation and do internally the so called oversampling.
So that, if I have a source at 44.1kHz, the output DAC automatically does a 4x oversampling and works at its best 176,4kHz.

Please forward this ticked to your R&D department, they absolutely know the answer.

Thank you.
Kind regards,
Andrea


Added byNicoleon2012/02/09 10:36:06 US/Eastern

Hi Andrea,
Simply put: Yes, our gear uses internal oversampling.

Hope this helps.

Thanks,

.Nicole
MOTU


Added byAndreaon2012/02/09 11:29:58 US/Eastern

Dear Nicole, this is good, we are approaching the closure of this ticked too.

Please ask to your R&D team these 2 last questions and copy me back the precise replies you'll get:
1) Do you confirm that any incoming digital stream at 44.1kHz and 88.2kHz is internally oversampled to 176.4kHz by the DAC stage of the Analog Output 1 to 8 and Mains? (If the reply is NO, please specify better).
2) Do you confirm that any incoming digital stream at 48kHz and 96kHz is internally oversampled to 192kHz by the DAC stage of the Analog Output 1 to 8 and Mains? (If the reply is NO, please specify better).

Thank you.
Kind regards,
Andrea.


Added byNicoleon2012/02/09 13:25:03 US/Eastern

Andrea,

I do not have the specific oversampling frequencies. Oversampling frequency is variable based on the system sample rate.

I am curious. Why do you ask about the oversampling rate?

Best,

.Nicole
MOTU


Added byAndreaon2012/02/10 01:24:29 US/Eastern

Dear Nicole, I am asking this to be sure about how the analog output quality is affected by the source input sampling rate.

Again, your R&D must know these two details because are typical of the DAC and architecture used.

Please ask to your R&D department.

Thanks and kind regards,
Andrea.



Added byNicoleon2012/02/10 10:39:31 US/Eastern

Hello Andrea,
I provided you with a specifications sheet in a previous TechLink, but for your reference, I will re-post them here:

Dynamic Range: 112db (A-weighted RMS)
Headroom: 16db (20dbu FS)
Available pre amp mic gain: 53db (60db on UltraLite mk3 Hybrid)
Sampling Rate: 44.1kHz - 192kHz on analog, 44.1kHz - 96kHz on ADAT Lightpipe, S/PDIF, and AES/EBU
Frequency Response at 96kHz sampling rate 20Hz: 48kHz +/- .05db
Frequency Response at 192kHz sampling rate 20Hz: 96kHz +/- .05db with a 2dB linear roll off from 48kHz to 96kHz
THD+N: .001% or better
Output Resistance: Under 100 ohms
TRS Input Resistance: 10k ohms
XLR Input Resistance: 2k ohms

These specifications are MOTU's public documentation for the 896 mk3 Hybrid. I'm sorry, but I am unable to provide any more specific information.

Hope this helps.

Cheers,

.Nicole
MOTU


Edit

Added byAndreaon2012/02/10 11:06:29 US/Eastern

Dear Nicole, this is not what I asked about!

I really do not understand what kind of Customer/Technical Support MOTU is providing.

I didn't asked for any corporate secret, just a normal technical details that is also present on any $50 CD player.

I am really without words.
I am very disappointed for the very bad level of technical support provided by MOTU.

Best regards
Andrea

[TipTop]

Hi Andrea,
In general, MOTU does not give out information like this unless you establish yourself as a developer. I'm sure if you would've told them you were a developer you would've been receive with open(er) arms. Everyone knows this about MOTU. Next time, maybe establish that fact up front.

.TipTop

[kgdrum]

fwiw
I think Nicole answered your question correctly.
The I/O is capable of recording 24/192 but if you are recording from a CD(redbook= 16/44)via spdif it will record 16/44.
Example:If you want to record a string quartet with the I/O @ 24/192 you set the I/O to record Analog and record 24/192
I/O 's are recording devices not upsampling DAC's.
If you record something digitally into the I/O there should be no conversion recording will import at the sample rate of the files(16/44)
Analog output is analog, digital input will be whatever sample rate you record at and then be converted to Analog.
Does this make sense?