I guess that's because , technically, Solo and PFL are different functions - bigger consoles have both. In smaller consoles the function is sometimes switchable (globally) between Solo & PFL. It's certainly useful to have access to either/both functions and, as Steve says, PFL is often the preferred option for live work.

If there's only a single button for this on each input (rather then both PFL & Solo), then a global setting for PFL/Solo is more straightforward than making it a per-input setting, and maybe a little less confusing than having to remember which inputs are in which mode, unless they're colour-coded in some way. If they were to be set on a per-input basis, then global "helper" buttons in the settings tab to "Set all to Solo" & "Set all to PFL" would be useful.

Could you clarify what you need a PFL for specifically in your workflow?
The Solo button turns on the audio only for headphones and won't be heard in the mix, but it does still follow
the volume level as set for that particular input.
(As that is usually more helpful to hear how loud it will be when switched live)

I'm guessing you need PFL to monitor the audio at a higher volume for some reason?

Regards,

Martin
vMix

Hi Steve,

Apologies but I am a bit confused as that is exactly what Solo is intended for.
You can hear audio inputs exactly as they will be heard in the live mix, without it actually being live and affecting the stream, recording or output.
When solo is on only the headphones will be able to hear it as long as it is remains muted at the time.
Regards,

Martin
vMix

I feel your pain Steve. Many video software solutions for live/broadcast media get this wrong unfortunately. A couple of weblinks for a different point of view.
http://www.mediacollege.com/audio/mixer/pfl.html
https://churchtecharts.o...s-the-difference-afl-pfl

The SOLO function is generally found on audio mixers (software/hardware) used in the production of music, mostly in a studio environment.

The PFL function is commonly found in live stage or outdoor environments, where the operator needs to hear the audio channel/s prior to the channel fader being opened, to verify level and quality of sound. This is via the monitoring channel using either headphones or speakers. Any number of channels can be PFL’d simultaneously for comparisons in sound quality or level. As the name suggests, the PFL audio is ‘pre-fader’ for the nominated channels/s. There is no effect on the master, or sub-master outputs. The PFL function also allows control of the channel gain, channel attenuation (not in vMix, sadly), the equalization parameters, and effects return gains to that channel prior to opening the fader and going Live.

It would be of great benefit to have this feature on each Input where audio is mapped in vMix, as well as the Preview monitor ( a small button in close proximity to the Preview display). It’s very important to be able to pre-listen sound in preview during live events, confirming that the microphone, external audio source or vMix Input is correctly set and verified for levels and quality. The audio metering should also reflect the audio levels when the PFL mode is activated. The nice thing about PFL is that the operator can make fine adjustments with headphones/monitor speakers even while the channel is on air, only listening to that channel/s. Keep in mind there are two types or sound mixers: Live performance (PFL) and Studio recording (SOLO).

Admin Quote “You mentioned being able to check the level prior to going live, well with PFL you can't adjust the fader level to fine tune it as it would have no effect, it is always going to be at the input level.”

With PFL you can adjust the channel gain/attenuation. The channel fader is generally the last control surface on the audio channel, and where the operator wishes to set the nominal position of that fader will be determined by the style of sound mix to be achieved. It is best practice not to have all the channel faders at maximum setting. Channel gain/attenuation on each channel is your friend. This is what is being referred too. Quote: “The PFL function also allows control of the channel gain, channel attenuation (not in vMix, sadly), the equalization parameters, and effects return gains to that channel PRIOR to opening the fader and going Live.”

Faders are designed to be used to fade in/out of audio channels, either rapidly or slowly, depending on the circumstances. Rarely does a professional audio operator simply switch the audio channel on/off. Generally faders are left down, unless those channels are being used. That’s a traditional workflow, and permits a visual indication of which channels are being sent to programme. An exception would be feeding sub-mixes A-B.

Admin Quote: “The trouble with input levels with ASIO devices is there is they are always 100%, there is no concept of pre-gain other than physical knobs on the ASIO device itself.” Correct, but also can be adjusted by a midi control surface. Though once in the vMix audio mixer environment channel ‘Gains’ only can be adjusted, there is no attenuation. As for other non-ASIO audio sources this would not be an issue.

It would be great to see a signal flow for all the sound modules in Vmix.

The problem with SOLO is that it is post-fader or AFL, and a dangerous way to operate. Which is one of the reasons why PFL/Cue exists on most Live sound mixers (Yamaha, Roland, Behringer ...) and not SOLO. Not being able to listen to the PFL sound with the video on the Preview Bus is also dangerous. Easy-As. One button ... Pre-Listen ... and cue the talent.

This thread is right on target.
When I mix music I always use solo in-place. The instrument is already "on-air" and I use solo to tweak it. But in Live Broadcast we flip almost all solos to PFL. There are not that many sources "on-air" at the same time, and tweaking can be heard and done in the mix mostly. We are most wanting to isolate what is coming up next to verify signal before air. To be honest I don't think I have ever used Solo in vMix in a show because of this and the shows we do. To be honest I could even use a global PFL setting/switch and that would be a start. Right now we have X-32's driving our shows, but we could do almost everything in vMix for smaller events if we had a PFL with the X-touch I am using now. :-)

This would also give us some of the "talkback" features we need for IFB.

This has given me an idea that I could use a script for a sort of AFL by launching the mute and solo at the same time. Might be a temporary work around????

HMMM

Thanks,
Steve

Quote Admin: “It sounds like people are using the fader itself to act as a sort of mute control, moving it up prior to going live.”

This is the workflow that has been in place for nearly 100 years. Radio, television and live sound production. PFL is not unlike ‘Preview’ for sound, just like the video preview monitor in vMix. The Solo implementation in vMix is more akin to to AFL (after fader listen). This is why the term, “open the fader on X” is echoed throughout the world. There have been many lively discussions on the Newtek and other forums regarding this misunderstanding by software developers on the subject of PFL, AFL and Solo. Again, have a look at, and understand the functioning of many popular live sound mixers from the major manufacturers. Look at the control surfaces, and you will see the ‘PFL’ or ‘Cue’ buttons on in close proximity to the channels faders.

There are many demonstration videos on ‘PFL sound” and “Gain Structure” on Youtube, have a look and you will better understand. Download a user manual for for a live sound mixer, and review the sound signal path in the diagrams provided within. Respectfully, this is how the audio world works. A time and tested workflow adopted by most manufacturers, driven by the needs of the sound engineers and operators. That is the strongest of cases.

Actually that is how I wondered on to this issue. It is not possible to click on both mute and solo at the same time. That is what it would take to get close to the desired function.

Best,
Steve

I am still not quite sure why there is the need to mute the input when activating solo, but if you wish to do so, simply setup two shortcuts
for the same button, the first to mute the audio, the second to enable Solo. They will be activated in order.

To summarise:

Solo in vMix is essentially an in-place isolation audio monitoring tool, useful for confidence monitoring at the same levels and effects as live. This is also handy when live, for example if one of the speaker's mics is crackling and you don't know which one it is, Solo can be used
to do that quickly and easily. (As I have done myself on a few occasions)

For this purpose, and for the reasons previously discussed, post-fader makes the most sense and provides a lot of functionality
to the user without them needing to learn the more complex analog mixer workflow required by PFL.

If others still want to make the case for PFL, feel free to post your support, but consider the question "how will it make the average vMix user's life easier?"
This is the primary question we ask when considering new features and provide practical step by step examples where possible.
(This is also good advice for other feature requests!)

Regards,

Martin
vMix

Hi Steve,

You are right, but the Solo in vMix can do both! It can be used prior to going to air when the input is Muted, and also to check for the unexpected when live as well.
May I suggest that a small change to your workflow to rely on Mute rather than the Fader might solve the problem.

The fader in vMix acts as both a gain and a fader in the traditional mixer sense, so think of it as a gain pot but with the channel fader
always set to 0 or unity.

Regards,

Martin
vMix