44/48 kHz, USB Audio and Helix

deeplfo deeplfo at gmail.com
Wed Sep 13 01:37:00 CEST 2017


The sampling frequency value represents how many audio data points you measure in a given time period, thus defining your audio quality.  It's the bit depth that represents the dynamic range of each of those data points, i.e. the headroom. So, for more detailed (accurate) representation of the audio, you would record at say 24 bits or more.  

You probably get some what of an improvement in audio quality by bumping the sampling rate to higher than 44.1 K values, but I'll stop here when it comes to discussing the mertis of higher sampling rate and perceived audio qualities :-)

mohsen

> On Sep 11, 2017, at 6:52 PM, Andrew Tarpinian <andrewtarpinian at gmail.com> wrote:
> 
> I decided on recording @ 48khz. The reason to record higher than your end format is you have more information when processing the audio with effects etc inside the computer. Supposedly 48 gives you just enough headroom without having to go through the headaches of 96, incompatible plugins etc... I have yet to research the conversion to 44, obviously it works fine exporting out of live on the surface but I want to see if there is a piece of software that does the conversion for the master more accurately. If anyone has any thoughts that would be cool. 
> 
> I'm also used to 48 coming from the video world. 
> 
>> On Sep 11, 2017, at 6:06 PM, Mikael Hansson <forums at deadmengods.com> wrote:
>> 
>> Hi bar,
>> 
>> I got the Line 6 Helix Rack this weekend and stumbled upon a few issues…
>> 
>> If you’re using it’s USB interface (8in/8out) you can easily send both the raw and the processed guitar to your DAW for recording. Combined with their Helix Native plugin, you can just fire up an instance of the plugin on the raw track, select the same preset and it will sound exactly the same as the processed recording. This is because the level of the raw recording is matched to the level hitting the hardware processing.
>> 
>> As I have another main interface, Focusrite Saffire Pro40, I tried setting up the Helix as an aggregate device. Setting it up wasn’t a problem but the Helix channels were nowhere to be found when I selected the aggregate device in Cubase. I found out that the USB Audio class compliant driver for the Helix requires running at 48 kHz so changing the aggregate device to that solved the problem…but:
>> 
>> I have never wanted to use 48 kHz since I only release 44 kHz material. Initially due to the CD format but is that even relevant anymore and do you really risk getting any artefacts converting from 48 kHz to 44 kHz?
>> 
>> Another thing is this lockdown to 48 kHz. The Helix supports 44, 48, 88, 96 kHz using their custom Mac driver which unfortunately has double the latency (about 20 ms total in/out) compared to the class compliant driver and it's supposedly only developed to alleviate problems that a minority of users experience.
>> 
>> Looking at the Apple USB audio tech specs doesn’t give any hint of why it shouldn’t be feasible to also make different sample rates available in the class compliant driver. Maybe someone here knows more about creating drivers for audio devices :-)
>> 
>> Other than that I’m very pleased. Luckily I got the rack version which has a guitar thru output making it easy to record the raw sound on another channel, but then I have to match the level by ear when running it through the Helix plugins…and if you’re not using the USB audio you miss out on sending stuff back to the Helix for processing (it’s a big a** multi fx if you want with several parallel multi fx lines available)
>> 
>> /Micke
>> _______________________________________________
>> music-bar mailing list
>> music-bar at lists.music-bar.org
>> http://lists.music-bar.org/cgi-bin/mailman/listinfo/music-bar
>> 
>> Listen to Music-Bar Radio! <http://stream.music-bar.org:8000/radio.m3u>
> _______________________________________________
> music-bar mailing list
> music-bar at lists.music-bar.org
> http://lists.music-bar.org/cgi-bin/mailman/listinfo/music-bar
> 
> Listen to Music-Bar Radio! <http://stream.music-bar.org:8000/radio.m3u>


More information about the music-bar mailing list