Higher sampling rate (Hardware Question)

[oosnoopy]

Hello, new to almost everything in this realm so my questions my appear a bit green.

I'm basically using Cantabile to play my Ivory VST's from midi from my keyboard. I'm currently using my motherboards on board sound card and the highest sample rate is supports is 96000 Hz. Will adding a better sound card let me achieve a higher sampling rate? If so is there anything anyone would recommend?



Also is there any advantage of using a (midi to midi card cable) as opposed to a (midi to usb cable)?

[TiUser]

Don't panic about high sampling rates... unless you are an audiophile manic with a very high end sound card the standard rates of 41.x or 48kHz will do as well.

I think it's more important to choose 24bit over 16bit if your soundcard provides this.

Quality is not only determined by the basic sampling rate and bit depth numbers - indeed, many D/A converters are HW wise 1 bit converters nowadays - but by the clock stability too. For instance my Virus TI as soundcard sounds better with 41.x KHz / 16 bit than my onboard realtec sound with much higher, better looking numbers...

But what you for sure do is waste cpu power with high sampling rates. 96 kHz will basically consume twice the cpu power as 48 kHz for the same sounds!


With midi it's best to use no classical Midi to anything PC converter at all but a direct USB to USB connect between your keyboard and PC as this is the fastest way transmitting midi.

Classic 5 pole midi connects are basically comparably slow, introducing a latency of approximately 1 ms per note! This means you never can send a cord's notes really simultaneously... If you send many notes on many channels via a single classic midi cable connect you run into severe sync problems the more notes you with to transmit simultaneously...

[dluther]

I'm basically using Cantabile to play my Ivory VST's from midi from my keyboard. I'm currently using my motherboards on board sound card and the highest sample rate is supports is 96000 Hz. Will adding a better sound card let me achieve a higher sampling rate? If so is there anything anyone would recommend?

Okay, there's a lot of heavy opinion in what I'm about to say, so take it with a grain of salt...

96KHz sounds awesome, but it's overkill for live playing. You have to consider your source material and the audio output stages for that material. If your speakers only go up to 16KHz, anything above that gets filtered out and your super sample rate is pretty much wasted in the upper ranges.

Second, 96KHz takes a lot of processing and big buffers to handle, which results in latency. In your example, you're getting 21.3 ms of latency, which is the time it takes for you to press a note on your keyboard until the time you hear it. For me, anything over 10ms is maddening, so you might want to experiment with 48KHz and 256 samples per buffer and see what kind of latency you get, and if it affects your play.

Personally, I'd play live with a lower sample rate and if needed, render audio at 96KHz (or 192KHz if you're so blessed).

Also is there any advantage of using a (midi to midi card cable) as opposed to a (midi to usb cable)?

It really depends on your MIDI interface. Lots of keyboard controllers have a USB connection that shows up as one or more MIDI devices, which is great because USB has a much higher data rate than MIDI does and you can bypass MIDI cables altogether. I once had a SoundBlaster Live card that had MIDI in and out ports, but they were the sub-DIN plugs that required adapters. Most computers don't have an actual MIDI interface, but rather a game port that requires yet another adapter to plug into the game port. The short answer to your question is "it depends on what's on the other end."

[oosnoopy]

Thanks for all the information. Everything seems to be rather clear expect on the sample rate. When I try a lower sample rate, I get slower response speeds (confirmed on the keyboard). This is why I thought a higher sample rate would decrease my latency. The 20ms delay is pretty noticeable with a weighted keyboard.

[TiUser]

What you found is quite logical when you consider that the audio buffer size remains the same regardless which rate you choose... The buffer is the bucket that needs to be filled in one calculation cycle. With a high sample rate the bucket is filled faster (and with higher cpu load) than with a slower rate...

You need to adjust the audio buffer size instead of the sampling rate to get lower latency... this will change cpu load again as well... you have to find a balance between buffer size and latency that works on your system. Changing the sample rate is not the appropriate setting to balance this out.

Click on the control panel button. There you should find the options of your ASIO driver to modify audio buffer size

[tony tony chopper]

Yes, pick your buffer size in MS, don't pay attention to the actual length in samples.
And no, you don't need 96khz, unless you're running plugins that don't care about aliasing, then yes it will do a difference, but you'd better switch to better plugins & spare your CPU.

[contrary]

I thougth that I would chime in and agree with the advise that's been given here ...... I recently did allot of research and a sort of cost/benefit analysis on the whole higher sample rate thing . The difference you have been hearing is real ; the converters on your mobo will sound better at a high SR ....

But that is sort of the issue really ; I did some listening test with an emu 1616m ( seperate sound card with asio drivers) and i could'nt really hear anything between the SR's . If you can hear a difference than it reflects poorly on the design and/or the execution of the a/d d/a converters ... It's that simple . The only real advantage I could ascertain was that at high SR's , non-linear processes like compression and limiting. ( limiting especially can use the extra samples in the lookahead function )



It can help comps in not producing aliases ( foldback ) and inharmonic distortions . But even then the cveat is that most times the benifit from these is only if you were really doing extreme mangling .... lots of pluggs can do reasonable compression at lower SR's and have no serious distortions.


There are also plenty of dynamic processors that up sample as a part of the pluggs internal archetecture ans save you from having to run the whole project at that rate to get the benefits.


good luck

[dluther]

This is why I thought a higher sample rate would decrease my latency. The 20ms delay is pretty noticeable with a weighted keyboard.

One thing that's making my eyebrows raise a bit is the "ASIO DirectX Full Duplex" driver. That seems to me to be an ASIO layer ON TOP OF DirectX which frankly sucks for audio.

What kind of sound card are you using, and can you find a native ASIO driver?

[TiUser]

...I noticed this too... but well, Asio4all does exactly the same thing and works most of the time well... but now you've made me curious in this question too...