Pops and Clicks, begone
there’s a lot of voodoo out there — instead, let’s be systematic
On the journey to audio nirvana, we have this far determined this:
So, most cheap simple gear is “kinda OK”
However: sometimes (ha! “often”, perhaps “inevitably”) things that are just OK turn out to disappoint, or the “magic smoke” is released, never to return.
This is not to rag on people’s products: the simple fact is, that all commercial projects are sold to customers and produced to a budget and hence will largely [a] work well enough to not be returned, and [b] not likely to look like it was produced by the Gods on Olympus
Getting things past the OK takes time and nudges
Re: the above I noticed the problem with ruined audio recordings a while ago, but lived with it, because frankly, it was a free software SDK connected to my laptop with a USB cable.
What was I supposed to expected?
A Very Good question.
So, from the above, we know that the intrinsic quality of the recording via the Amp was not half bad: we also know the quality of the dedicated interface is even better, and has excellent noise rejection.
There were still some clicks and pops, and after several days attempting to find a common factor, I decided I had failed.
There are numerous pieces of advice out there about, in the vein of:
use high sample count / high latency for playback
low sample count / low latency for recording
Quite how we’re supposed to record without some playback is not addressed.
Also, a system that needs its parameters tweaked each time you change your mind about whether you’re using either of its two primary features, has quite simply failed.
So, the internet did not seem to be in agreement that the Studio 24 is terrible (it’s not), so I have to assume this is one of the depressingly regular “you need to find the magic configuration” scenarios.
Lest I give you the impression that the Audio Interface has so many problems: I should point out, that the 2 inputs and the gain trim knobs and the output knobs are simply very, very useful. I can set the levels up perfectly and simple leave them — knowing that recording and playback will be just right.
Basic diagnosis for the pops and clicks was
(using the 5 Whats method):
What is the problem?
Noticeable, intermittent clicks and pops in playback via the DAW
What are Clicks and Pops?
Clicks and pops are sounds generated when wave-forms do not have the normal smooth characteristics of real world sound, but instead have sudden jumps in level
What produces Clicks and Pops?
typically: problems with getting chunks of audio to the audio device on time, resulting in incorrect waveforms. Also data corruption could reproduce this, but we can eliminate that as the popping is very easily controlled by changing sample counts, which is precisely not what data corruption would normally imply.
time waits for no man, so when there is the merest delay in getting samples to the speaker, something will happen — generally if there is a gap, or a sudden leap in the signal as samples from different points in time are output in sequence, there will be a very loud, broad spectrum, click or pop
What process in a computer would generate delay?
There are many causes:
- software faults — given this software has been in use for several years on this machine and has regularly performed flawlessly, this seems to be a stretch to adopt as the primary culprit
- hardware faults — in this case, almost everything is brand spanking new, or refurbished, again would be surprising, though not impossible
- attempting to ask too much of the computer — a given device can only produce so much throughput — even coming close to that limit in a generalised device like a laptop is asking for intermittent problems. The laptop is a Dell XPS 13 9360 — recently refurbished and seems capable enough. Always check your free memory, though.
- inappropriate design — the electronics and device may be capable of impressive performance, but if the timescales you are asking for were not considered in the system design, it may never deliver them reliably. We can eliminate this possibility simply be noting other people use laptops and computers with decent results.
- buggy device drivers — the hardest charge to make stick in court! The most sensible approach is go with the mainstream. In this case, Microsoft’s drivers or a 3rd with very good reputation. This is generally my approach unless I am placed under severe duress.
- inappropriate configuration — the single most straightforward way to screw the pooch and also the easiest to implement. This is a good candidate as it is the most common cause of faults (CITATION NEEDED)
What is the procedure for diagnosing mis-configuration?
Ok, now we are getting somewhere.
There are few parameters to play with usefully, hence why this problem is both
- super frustrating
- also, as a corollary of having few levers: it is a problem that, if it has a fix, has one that is quite easily found — \o/
So, we break it down back to the Not Even Set Up state and then Change One Thing Only
sidebar: processes and products that change more than one thing and give you no options: avoid avoid avoid
Fault finding
Plug it in
it lights up, and with a blue light, which implies the device was correctly initialised
I did discover one change which I applied and made permanent, which was to connect the interface audio out directly to the powered speakers, thus removing them from the loop (including the USB connection)
Attempt to use Studio 24 directly
This does not work as it stands.
Attempt to use Studio 24 with supplied drivers
This was kinda OK, but with audible pops and clicks
After installing the drivers: his was irritatingly close to just working, but even for large blocks of samples, there were intermittent pops more than once a minute. Uninstall the drivers.
Using ASIO4ALL alone
This did not seem to work as the device was not recognised.
Using ASIO4ALL with the Studio 24 device
After installing only the supplied “Studio USB” driver, the audio interface could be seen.
The initial sound was terrible: but for this configuration it’s very east to tune the device block size — results are atrocious below a certain size, but perfect above another.
Results
This is my current configuration:
11.3 ms is equivalent to standing 3.3 metres from the amp: this is not the kind of setup that with going to impact your concentration.
The previous settings I had to resort to where in the region of 50 ms however, which is more like is 16.5 metres — that’s like playing next door to the amp.
Conclusion
Fixed
With the right setup of the device, the behaviour is perfect.
I was worth looking for the solution.
So far, I have not heard recurrent pops and clicks: instead there is a very quiet and noise-free sound experience. I can set up the level trims of the inputs and simply leave them so that for recordings the initial captures are already the right level in the mix, making it much simpler to record and hear the track while monitoring and playback.
Diagnosis
This is merely a set of my speculations based on the observed behaviour, but given
- there is a setup that works
- hence, all the components in that chain are working, when in that particular chain
- therefore, it seems reasonable there is a difference in the operation for the configuration between the direct Studio 24 driver and using ASIO4ALL
The Studio USB driver configuration does appear to work for a much wider range of Device Block Size values, but is afflicted with pops for all of them. The ASIO4ALL configuration using the device has major problems with sizes below a certain threshold, but it works flawlessly a little above that threshold, and fortunately, that threshold is one that yields a very usable latency.
