SIP / PFL How is it done?

[peter purpose]

Gentlemen,
Can anyone point me to some info on how to impliment soloing.
Or put it in laymans terms for a fool.

Grassy arse
peter

 

[Bjorn Zetterlund]

Hi Peter,

On my soundcraft, it is simply a double pole switch per channel. One pole is used to switch the actual audio to the solo bus, which is a virtual bus just like any other on the desk. Any solo'd channel will send audio to this bus and therefore you hear a mix of whatever is solo'd.

The other pole of the switch is for a sense line, which also runs along the main ribbon connector. I think this sense line is normally held at ground, but when any channel is solo'd, that channel will pull the sense line up to 24V. The master section has some audio switches that will send the solo bus to the monitors rather than the mix when this sense line is at 24V. On a simple desk like the soundcraft, that's it pretty much!

Bjorn

 

[daArry]

evenin'

dunno if any good, but peep page 9: http://www.apiaudio.com/man8200.pdf

 

[peter purpose]

Thank you gentlemen... the mists are clearing.. :thumb:

 

[daArry]

and for dessert:

http://www.audient.co.uk/Uploads/Images/AZTEC_BLOCK_DIAGRAM_AND_MOD.pdf

 

[peter purpose]

[quote author="daArry"]and for dessert:[/quote]

Phwoar :thumb:

 

[Rob Flinn]

On my trident a double pole switch on each channel strip.

One pole switches that channel onto the solo buss. The other pole trips a double pole double throw relay, which switches the master out from looking at the stereo bus to the solo buss.

 

[peter purpose]

Cheers Rob,
I'm liking this method. Presumably I could put a resistor in series before each channel joined the solo bus in order that they'd be summed nicely if more than one channel were solo'd.

pooter

 

[SSLtech]

Problem with doing it the way that Rob describes is that it removes the feed from the stereo buss. That makes it unsuitable for "on-air" use, or checking during a mix print.

Petey Porpoise,
Are you sure you mean "PFL" SIP?

There are a couple of ways of doing Solo-in-place, most common is the "destructive" solo, which mutes everything other than the solo'd component.

the second one, which is common on Neve consoles, is to AFL by leaving everything as-is, but the same signal line which in destructive solo mode would mute everything with a button not pressed is used to instruct the monitor to switch away from the stereo buss output and switch to the stereo solo AFL line. The signal at the two outputs of the pan pot (post fader) is then also switched to the AFL busses (left & right), and since the panpot is post fader, this is AFL SIP.

There has never been a PFL SIP as far as I've encountered. -Not to say that it's impossible, but it might be more likely to be useless in that it ignores all fader attenuation, so why would panpot attenuation be important...? Balance info is lost, so stereo position info would not be much use.

The AFL SIP is useful in that if you then add a "-6dB-at-centre" crossfade blend of the stereo buss to your stereo AFL, you get SIF, or Solo-In-Front.

Now that's happnin!!!

Keef

 

[Rob Flinn]

Problem with doing it the way that Rob describes is that it removes the feed from the stereo buss. That makes it unsuitable for "on-air" use, or checking during a mix print.

There is a way to do this with my desk, but I`ve modded it to do this, & its a little difficult to explain. My desk has matrix outs, because it was a live/theatre desk, which is what I`d use for "on air" as Keith describes it. These also feed to the master out for control room monitoring, which is where the solo buss gets fed to when selected.

 

[Rob Flinn]

I'm liking this method. Presumably I could put a resistor in series before each channel joined the solo bus in order that they'd be summed nicely if more than one channel were solo'd

electronically the solo buss summing amp is identical to any other summing amp on the desk. If you think about it you might only have 1 channel punched into the master buss, which is the same as 1 channel being solo`d, so all of the summing amplifiers are exactly the same.

 

[peter purpose]

OK gents..It's all becoming clearer.

Keef.... Yeah, sorry about the confusing title. I should have said PFL and/or SIP.
The 'on air' aspect doesn't really bother me and would make things super simple.
I'm assuming that some sort of logic (I haven't a clue what that is) is needed to impliment true SIP, but if you could point me to an explanation, twood be marvellous.

ayethengyaw
peter

 

[StephenGiles]

Perhaps someone would explain the concept of Prefade Listen as it appears to be properly called - or I think Solo on my Alesis 1622. I would be most grateful if you please.
Stephen

 

[peter purpose]

Stephen,
Pre Fade Listen is exactly that. The signal is taken before it hits the fader, so wherever the fader position, the signal remains at a pre fader level.

peter

 

[StephenGiles]

So how do you use that Peter?
Stephen

 

[peter purpose]

Stephen,
PFL for a quick and dirty listen I suppose.
SIP, or solo in place is fab for hearing it where you put it.

peter

 

[Scodiddly]

PFL soloing is a way to listen to individual channel(s) without affecting the mix output. This is really handy in live audio, where there might be a problem with a signal but you can't figure it out listening to the mix. So, you slap on your headphones and start hitting the solo buttons, listening to suspect channels until you pin down the bad one. You might be wanting to check on a source that's currently faded down or muted, so you want "pre fader listen".

SIP soloing is more of a studio thing, usually because using it affects the mix outputs as well as the monitors/headphones. Many consoles have a glaring red indicator for when SIP is selected - wouldn't want to do that at a concert! But in the studio it's a handy way to tweak parts of a mix, such as several mics on a piano. You'd solo those channels instead of having to mute all the other channels. Top-end consoles will even have a stereo buss for soloing in place.

Also there's a nice feature you see on upper-end consoles, which is a "solo cancel" button. The channel solo buttons are momentary, so that a the solo cancel button can "un-solo" all the soloed channels.