magister said: Somewhere, years ago, I picked up the idea that one should not set gain in a phono stage higher than necessary.
This is because phono pres are very sensitive and can pick up lots of RFI/EMI. If you do not need the gain lower gain settings may pick up less noise, keeping your noise floor lower. You then can make up for the lower overall gain by turning up your preamp. This is a great example of dealing with gain staging issues.
Here, I am assuming the level control you are changing is digital as you wrote of 20 levels of gain. There are usually only three or four analog gain setting on a phono pre. I infer from 20 that it is a digital volume control and thus one should use all of the gain if you need it. (Of course, the NPC may have digital switching of analog gain devices or something else going one that allows this level of control.)
I believe that the phono gain on the NPC is analog. As I remember the gain stages are based on the ‘Gain Cell’ design and the gain control is not in the circuit path. The phono gain is set with dip switches on the back panel, thus the steps.
I believe that there should be a separate gain setting for the A/D too, probably accessible from the menus and probably also from the USB connection. This should be double-checked if it has not already.
Oops! I just had a look at the product web page. The dip switches on back are for cartridge loading and gain is done fron the front panel… Still a digitally controlled analog gain.
Unchecking "Use WASAPI" eliminated the static sound. The Input Source is the default recording device, which is the PSA Audio driver that I had previously installed. IIUC, PSA supplies an ASIO driver, so maybe there was some conflict between that and WASAPI. Problem #1 solved.
In the Vinyl Studio help file under "Record Level," above the third screenshot it says "If you have a USB device on Windows Vista or later, the Check Level dialog might look like this." I have Win7 and the NPC is obviously a USB device, but I do not see the item "Set digital gain to 1 (recommended)" that is shown directly under the input source in the screenshot. Nor could I find such a control in the menus. Could this be involved in the low recording level?
I have now got my grubby paws on an NPC for testing and I have finally got to the bottom of this. The short version is to avoid using WASAPI in VinylStudio with the NPC under Windows until we work around a driver problem, which we will do in the next release. Essentially, the driver lies about the buffer size which upsets VinylStudio's polling mechanism, but, as I say, we can fix it. There is also another issue which makes using WASAPI undesirable with the NPC but I will pass over that for now.
So, in the meantime, either:
uncheck 'Use WASAPI for Recording' and set Windows' shared recording format (sample rate and bit depth) to whatever settings you are using in VinylStudio
use the ASIO driver (select ASIO as the Input Source in VinylStudio's Check Level dialog to do this)
The first solution has the advantage that you retain control over the recording level via the slider in VinylStudio's Check Level dialog, which is useful. The second is simpler. To set Windows' shared recording format, see the following link kindly provided by one of our rivals :)
Don't worry about the 'Set Digital Gain to 1' thing. That's for budget USB devices that offer no control over the recording level. With such devices, Windows scales the incoming data in the digital domain unless you do this, which is highly undesirable.
uncheck ‘Use WASAPI for Recording’ and set Windows’ shared recording format (sample rate and bit depth) to whatever settings you are using in VinylStudio
use the ASIO driver (select ASIO as the Input Source in VinylStudio’s Check Level dialog to do this)
When I unzipped the file I downloaded to install the PSA USB driver, I noticed an “ASIO” item along with other stuff. So I’m guessing that an ASIO driver is built into what PSA supplies, but maybe Paul M. or Dennis can confirm this. There is no separate ASIO choice, just the PSA driver. With my test recordings using the PSA driver, I did have control over the level using Vinyl Studio’s sliders, although the level was lower than I expected it to be (as I explained earlier).
Paul, do you have any comments on the recording level issue? Could the fact that I was recording at 24/96 have an impact on the level? In another thread on compression and the NPC, Paul M. mentioned that he needed to raise the gain to take advantage of 24/96 – is this the same issue I experienced?
magister said: So I'm guessing that an ASIO driver is built into what PSA supplies,
Yes, it is an ASIO driver.
magister said: Could the fact that I was recording at 24/96 have an impact on the level?
Not unless there is a bug in Vinyl Studio which screws up the volume when recording 96/24. I am certain this is not the case. :)
All of the volume levels of 44/16, 96/24, 22/8 - and any other digital resolution and bit depth - are the same. A greater sampling rate or bit-depth merely allows one to record with finer granularity, greater detail (and quieter sounds). The peak volume, RMS volume, lowest volume - all are the same. Regardless of format.
One does not, and cannot, "raise the gain to take advantage of 96/24." 96/24 cannot record a louder sound than 44/16 can. The peak level of 0dBFS (full scale), the loudest possible digital level, is always the same - regardless of bit depth or resolution.
96/24 can record really quiet sounds however that 44/16 cannot;that is, 96/24 can capture sounds below -96dB.
Of course, if the sound you want to record is less than 0dBFS you can always raise the input level to make a louder recording. Again, this is the same regardless of digital format. For example, if the peak level of the recording is -6dB, one can raise the level by 6dB. This is true for 44/16 and 96/24.
Paul, do you have any comments on the recording level issue? Could the fact that I was recording at 24/96 have an impact on the level?
No, as Elk says, that doesn't change anything. I would either increase the gain of the phono stage on the NPC's front panel or normalise (or manually adjust the preamp sliders) after recording. You've got plenty of dynamic range @ 24 bit so you won't lose anything by doing this.
I'm not sure why the ASIO driver is missing on your system - it's present on mine. I got the driver from here:
That said, if you're happily recording with the Windows driver I'd stick with that. Just make sure you set Windows' shared recording format as described in my previous post.
Perhaps uninstalling the PS Audio USB driver, rebooting, and reinstalling the driver will help.
My system displays the PS Audio driver as one of a number of ASIO options I have for playback. (The others are for items such as a multi-track recording interface, etc.)
I would UNINSTALL the driver while the USB is still connected.
Once the driver is uninstalled then disconnect the NPC, turn off computer, boot back up, re-install the driver and once this is done reconnect the NPC. Do so exactly as listed…
This may or may not work as I envision, depending on how M$ and Windoze are feeling at the moment.
wingsounds13 said: I would UNINSTALL the driver while the USB is still connected.
Why would it make any difference if the USB is connected during the uninstall?
I typically disconnect the device at issue, but I assume the force uninstall would have the same effect if the device is connected or disconnected. Why do you think differently?
That has just been my experience with Windoze. In the pre NT world the best way was to boot up in ‘safe’ mode and you could access and remove any and all drivers ever loaded into the registry. Since NT safe mode is not quite the same. I find it more consistent to remove the driver of a connected device. Of course, this is the experience of one computer tech and not the word of The Oracle.
Thanks for the followup. I’ve been busy with other things but will have some time next week to experiment more with recording from my NPC. I do see the Asio driver now (not sure why I didn’t see it before). One thing to note is that the NPC must be connected or the installer program will not work, and the PSA drivers are not visible in Device Manager if the NPC is unconnected.
I installed the driver some time ago to try USB out to the PWD. The instructions at the time indicated to connect the PWD prior to installing as well.
However, I see the driver as WaveStream even without the PWD connected (XP Pro). (I do not use the Bridge and do not have that WaveStream installed.) Interesting you do not see it without the NPC connected. No biggie I am sure.
