LabVIEW
VIEWLAB for recording audio with protools
Hi AJ,
@AJSPARK4444 wrote:
i have a 2 channel sigma delta lynx audio ADC with a good preamp chandler tg2 with a micophone first what kind of signal conditioning do i need for this system ?i read somewere that it's better to implement a sample and hold before the adc for a better convertion is it true ? i guess all the calibrations will go hand in hand with the conditioning circuits ?and what language do i need to learn to aquire data with labview ? I'm recording music so i need to know how i'm gonna implement that with the DAW protools ? is there any connection between labview and protools ? is it a mistake to record directlly from protools without coding in labview ?
When you read "something somewhere" then you should provide a link to "somewhere" to allow us to verify your information… (I wouldn't consider a sample&hold as signal conditioning. Depending on ADC type the S&H is already included in the DAQ device - that's not the part you need to worry about.)
When you talk about some other hardware/software (like "DAW protools") then you should provide a link to a website with information about those software… AFAIK there is no connection of LabVIEW to any "protools".)
As long as "record directlly from protools" gives you the results you expect it surely is no mistake to record data "without coding in LabVIEW"! (When you want to use LabVIEW then you need to learn LabVIEW.)
It also helps to write messages with correct grammar and punctuation rules. It also helps in a LabVIEW forum to spell LabVIEW correctly, especially in the thread title!
Hi AJ,
@AJSPARK4444 wrote:
i'm talking about the lynx E22 pcie sound card ,you can see the image below there is no sample and hold in this card because a sample and hold contain a mosfet with resistors,capacitors and opamps
Ok, now you give us a brand and name for this device. Do you really think you would notice such sample&hold circuitry by looking for some discrete mosfets with additional "breadcrumb" around them? They are built into the ICs holding the ADC/DAC circuitry! This card even uses a FPGA, so the S&H could even be created with software inside the FPGA…
Your soundcard is a high-end device: I don't think you can improve their performance by attaching an external sample&hold circuitry. How will you trigger the S&H according to the internal ADC conversion cycles (at a max of 192kHz)?
The need for S&H circuits also depends on the kind of ADC, see whitepapers of all analog IC manufacturers like this.
@AJSPARK4444 wrote:
which sha brand do i need for my 24 bit sound device?do i need to learn C++ for data aquisition or the simple play button in protools is enough ?
I don't think you need any external S&H. If you don't believe my guess you should call Lynx to advise on additional hardware for their product!
When you have questions on this "protools" software you should ask in a "protools" forum. This forum is about LabVIEW…
@AJSPARK4444 wrote:
i'm speaking about a 940 page book called THE DATA CONVERTER HANDBOOK,in the section 7-4 they say that the sha amplifier when used either internally or externally,the sha performance is critical to the overall dynamic range,and play a major role in determining the SFDR,SNR of the system,now i don't know if i speak english or another language but you visibly need to read this book
Why don't you reference your information sources right in the beginning?
@AJSPARK4444 wrote:
First thing don't speak to me like that you just need to calm down
I didn't needed to "calm down", I just rephrased your rather generic question for a very specialized task/problem.
When you have problems with this you should rather read articles like this…
Quite a thread. I'll summarize for my own organization.
- OP asks for help and provides very little information.
- GerdW asks for more information, while attempting to make suggestions based on missing information.
- OP says GerdW needs to calm down and calls him ignorant, then tells him he must read something.
- Kevin (another volunteer) tells OP that they are asking too much of GerdW, or of anyone here.
- OP seems to try to say they weren't asking for Kevin's help. Paraphrasing they seem to say "butt out".
There is certainly disrespectful and unpleasantness taking place here. OP I suggest reading with the Unofficial Forum Guidelines, this will help you in getting your questions answered more easily in the future.
I'm not understanding your claim about a S&H circuit providing better dynamic range. S&H may be necessary depending on the used ADC technology, for instance when using a SAR (Successive Aproximation ADC). Here the signal is sampled & held and then over several stages successively quantisized into a digital signal. Without a S&H, the input signal would change during the quantisation and the resulting digital pattern would be spread and potentially provide completely erroneous values.
There are other ADC techniques that will not benefit at all from a S&H circuitry as they basically convert the signal in one single go from an analog signal to a digital value. In fact in terms of analog puristic reasoning a S&H circuit is an additional potential distortion in the analog signal path that will actually reduce the accuracy of the signal.
So just because you read somwhere that a S&H circuit is the golden apple that makes all analog to digital conversion better, doesn't mean that this is correct. It very much depends on a number of other factors such as what ADC architecture it uses internally. SAR ADCs are cheaper to build than ADCs that use a voltage divider network with individual comperators for each digital quantisation level. And I'm pretty sure your 950 page book somewhere spells this out, maybe in the margins. If not, it's not worth the paper it was printed on. Also such ADCs have a very high calibration effort during manufacturing to make sure their linearity is good.
SARs or also DeltaSigma ADCs have a technologically more complex operation but that is mostly in the digital part of the circuit and that can relatively easily be very highly integrated without increasing the cost of the whole circuit very much. Anything analog is a lot more difficult to integrate properly to achieve a good accuracy, linearity and signal/noise ratio.
And yes you need to calm down! This is a forum mostly driven by volunteers. And most of all it is a forum about LabVIEW. Sure some people use LabVIEW to control all kind of hardware, from a particle accelerator at CERN, to a little small Arduino Uno. Such specific questions about ADC technology are definitely not at the right place in this forum. Your last sentence in your first message even sounds like it was just thrown in to somehow make it sound like it is about LabVIEW. It makes however no sense at all.
