Monitor controller/switcher ideas - need some opinions

[Curtis]

Hi chaps,

I'm currently brainstorming a new project for an active monitor switcher/controller. Something a little bit like the Presonus Central Station - headphone amp, level indicator, source switching, cue feed, output switching, mute/dim/mono, big knob (ooeeerr) etc.

In your expert opinion(s) if you were to engage the Mute function on such a device and then twiddled the main volume knob, would you expect:

1 - the mute function to automatically disable as soon as the knob was rotated in either direction
2 - the mute function to automatically disable only if rotated clockwise
3 - the mute function to disable only when manually disabled?

For items 1 and 2, would you expect the volume to automatically return to the level it was it before the mute function was engaged, or start again from zero? Or something else?

My thinking is version 2 with recall-last-volume, but maybe people here have better ideas?

Thoughts?

 

[Sleeper]

On mine the switching is all analog and the mute switch is Post-volume so i have to disable the mute to hear something. but-I like it and it works great.

one idea about the other setups...

What if you had a too loud source. don't think you would want to touch the volume knob and unmute, you would want to turn the volume down and then unmute

Kelly

 

[valvehead]

I'm working on something like this. I'm planning on using 7 relays per channel for 128 1dB steps. Everything will be controlled by a PIC microcontroller: main volume, mute, mono, and source selection. I'm quite new to the PIC language, so it may take me a while.

 

[EKADEK]

hi curtis. my cross for your survey is definitely a 3. the less i have to THInk about what my volume knob is going to do when i just touch it.. the better . no second guessing please and definitely nothing fancy up in the monitor path. clean clean clean. heres a thing i made a while back. the left side has 2 pultec MB1 type microphone amplifiers (optional) and the right side is a stereo/reverse/mono. volume. solo left. solo right. spker 1. spker 2. 4 stereo source control room monitor console. big old ampex meters. the make up amp is a 4 transistor single ended circuit . lots of headroom. very clean.

 

[promixe]

Choice #2, but starting from zero would be only second best to choice #3.

Because imagine if you were at -20db (assuming your range is -60 to 0). You push mute, then turn the volume knob clockwise and it goes to -60, -59, etc. You loose your previous -20db point, what if you touched the volume accidentally and now you have to perform several unnecesarry turns to go back to where you were pre-mute.

Or if you are at -20, you push mute and then want to be at -40db when you unmute? Only scenario #3 allows you to do this.

So, practical (read: real-world) point of view is to do #3.
But I dig #2 from zero as well.

PS: However, if you are using a rotary encoder for your volume control, get one with integrated pushbutton, then you can alternate between #2 and #3 - if you push and rotate, it works relative to mute (i.e. starts from mute and up) and if you just rotate without pushing - it's a conventional #3. Then you can't mess up by accidently touching the knob and blow whiskers off your cat. =)

Hope this makes sense =)

I'm planning on using 7 relays per channel for 128 1dB steps

Valvehead, are you basing this on MCS's method? If not, could you elaborate on your approach?

 

[Curtis]

What if you had a too loud source. don't think you would want to touch the volume knob and unmute, you would want to turn the volume down and then unmute

Which is what option two allows you to do - it stays muted when the volume knob is reduced, and only un-mutes when the volume knob is advanced upwards, or mute is manually disabled.

I'm working on something like this. I'm planning on using 7 relays per channel for 128 1dB steps. Everything will be controlled by a PIC microcontroller

Yeah, mine's all PIC controlled too, but I was planning on using a TI PGA2310 for the volume control section (got a few lying around at the moment collecting dust).

Or if you are at -20, you push mute and then want to be at -40db when you unmute? Only scenario #3 allows you to do this.

Still covered by version two (see above).

A really crap example, but I once had a TV that did exactly this. You could mute the sound with the remote, reduce the volume (all the way to zero if you wanted) while muted and it would only un-mute if you physically hit the mute button, or advanced the volume up by one notch. So you could start at -20dB, mute, wind the volume down to -40dB and then click the volume up and have sound again. I always thought that was a pretty neat idea, and hated the next TV I had because it would un-mute if the volume was moved in either direction.

Thanks for the ideas, guys :thumb:

 

[PRR]

I work alone, hit Stop if I don't want to hear, though a DIM might be useful.

128dB range??? OK, cutting to 63dB or 31dB only saves $5 or $10.

Here's how I think and work.

There is Reference Level. A properly leveled final track will play at nominal level. In movie work there is now Dolby Level, which was rapidly accepted because it really is how professionals have set their monitor knobs for decades. If the track is done right, you don't feel an urge to move the volume knob. Working with a freely-turnable monitor gain invites erratic track loudnesses.

On my current JVC, this is "1.9".

Tracks come in unfinished. I work with live acoustic music with narrower dynamic range than modern digital recorders, so I often have long passages with peaks 15dB below digital clipping. When auditioned at standard playback gain they are weak; I will normalize. But I may want to work un-normal for a while.

So I may be working for a while with 12dB-18dB boost. "4" to "6" on my JVC.

I also have questions about the soft parts. Is that hum? Truck rumble? Radiator clank? Should I do something about it? Sometimes it takes 20dB-30dB boost to bring un-normalized "quiet" up above room noise. "6" to "9" on my JVC.

This knob is right AT eye level (actually 5 degrees up and right).... I always know how much monitor gain I have on tap. (If it were not at eye level I would file a deep notch in the knob so I could feel the setting; my portable box has that.)

So if I wanted to move from a simple pot to a PIC:

BIG "Reference gain" button.
Small buttons for Dim, Mute, denormal boost, and "listen to hiss loudly" boost.
Said buttons should BLINK when enabled.

Depth of Dim, boost, and big-boost on dedicated pots.

Reference gain is set by studio electroacoustician, according to Dolby Reference or other guide, and is not user adjustable. (For multiple monitors, each needs its own gain set, and the speaker switcher should set the appropriate gain for that speaker.)

Dim depth is really your "mix" between the track and whatever else you are hearing (phone, client, ballgame) and will vary with situation.

Denormal boost is roughly how under-recorded your track is, and (for me) tends to be near-constant over a master.

Big-boost is very trouble-dependent: a bit of clarity in a soft part versus trolling the noise floor, and (if you PIC) might reset to +10dB when any other mode is touched. My ears are old, so I would like big-boost to be hard to hit by mistake; maybe a 3-second press.

It is tempting to use time and combinations to reduce the number of costly buttons. That is a mistake, like 2-button watches and monitors which can NOT be set by a mere human brain which is not as smart as a $0.69 PIC.

 

[bcarso]

[quote author="PRR"]It is tempting to use time and combinations to reduce the number of costly buttons. Mistake, like 2-button watches and monitors which can NOT be set my a mere human brain which is not as smart as a $0.69 PIC.[/quote]

It is somewaht amazing to me how many people still believe that pushbutton controls are somehow better than knobs, not realizing that they were adopted to save money.

Not that there is anything wrong with making something cheaper---but at the expense of functionality?

I had a quasi-partner who insisted that an instrument be modified to use pushbutton up/down gain controls because the competition did so, and it was more modern and dare I say "digital". He could not grasp that it was not for ease of use, but for economy. But he also had so little confidence in himself that he was mostly limited to copying trends, almost never setting them.

 

[Curtis]

128dB range??? OK, cutting to 63dB or 31dB only saves $5 or $10.

Well the chip will do 128dB, but I had no intention of using it to that degree. My scratch code at this point limits it to a 90dB range from mute to 0dB. Realistically I know I'll probably never go above -30dB, but I may want more on tap if I exchange my power amp or speakers for less sensitive models, or if my listening room changes.

So if I wanted to move from a simple pot to a PIC:

BIG "Reference gain" button.
Small buttons for Dim, Mute, denormal boost, and "listen to hiss loudly" boost.

Even so I can think of situations where I might want to go to levels in between these. And like your JVC volume control, there will be points on the "big knob" that the user will familiarise themselves with as the levels to listen to. Despite the fact that my car stereo has a rotary encoder for a volume control, I know that when the LCD display says "vol=20" it's sufficient level for my CD's to come out the speakers loud enough to get over the road noise at 110kph and for me to sing badly over them :razz: .