Volume pedal for FRFR monitor?

andyg_prs

I have two current gigging set ups.....my AX8 and my amp/pedalboard via a CaptorX.  In both cases I present the left output via XLR to FoH.  I only present mono.

In smaller venues, I can't always get a personal mix in a wedge.  I have a Yamaha DXR10.  I was wondering about using it as a personal monitor, taking one output and sending it through a volume pedal to control the level.  Dpeending on the band volume and song, it needs a tweak live and I can't be reaching around the back of the DXR10 to do that.

Is there any reason why that wouldn't work?  I have a variety of volume pedals....does the type of volume pedal matter?  I think in both cases it's just a line level so I don't think it would be too much for a standard guitar volume pedal....but I could be missing something?

Musicwolf

I'm not sure that I'd want to use a foot controller (not precise enough / easy to knock) but I use one of these between the output of my XR18 digital mixer and our powered PA cabs.  Very easy to tweak on the fly plus a handy mute button for between sets or if we were to get uncontrolled feedback.  Just position it within easy reach (typically it sits on a shelf attached to my mic stand.

Voxman

Interesting thread as I too find it awkward to adjust the rear volume knobs on my Headrush FRFR108's when I use one as a stage monitor, particularly when it's angled on its side.  I have stood it on its end however, that makes access to the rear volume knob much easier but then you lose some of the 'angled up' benefit.

I would prefer a floor controlled solution so like the volume pedal idea, but agree it's too imprecise and can easily be knocked.  So the Swissonic unit looks interesting. 

andyg_prs

Voxman said:

Interesting thread as I too find it awkward to adjust the rear volume knobs on my Headrush FRFR108's when I use one as a stage monitor, particularly when it's angled on its side.  I have stood it on its end however, that makes access to the rear volume knob much easier but then you lose some of the 'angled up' benefit.

I would prefer a floor controlled solution so like the volume pedal idea, but agree it's too imprecise and can easily be knocked.  So the Swissonic unit looks interesting. 

I've not anyone suggesting that there would be an issue with a volume pedal handling the signal so far......and I have an old, if big Morley Power Volume that has a minimum volume setting.....by increasing the minimum volume I'd have thought you'd do ok.....it's monitoring after all.....so you could set the volume you think you need as the minimum.....and then you have a range to increase mid song....and if it's still not enough, you could always adjust the FRFR in between songs.

Also, too little volume is worse than too much (within limits) so you can generally move away from the monitor a little to deal with that.....until you adjust at the end of the song.

p90fool

I made something similar to the Swissonic controller, except big and robust enough to be able to move it with my foot. 

You can see where a rotary controller is set before you start the song, whereas I was always accidentally muting myself with a rocker pedal. 

ICBM

andyg_prs said:

I have a variety of volume pedals....does the type of volume pedal matter?  I think in both cases it's just a line level so I don't think it would be too much for a standard guitar volume pedal....but I could be missing something?

Level won't matter for a passive volume pedal. If you have the option, use a low-impedance one (50K or less) as otherwise the taper will be very steep. Best of all, if it has a minimum volume setting, eg one of the Boss ones, you can set that high which will restrict the range of the foot pedal.

Roland

ICBM said:  … if it has a minimum volume setting, eg one of the Boss ones, you can set that high which will restrict the range of the foot pedal.

Or in Fractal land you can limit the range in your settings.

andyg_prs

Actually I forgot, the CaptorX likes XLR to PA......to get into  a volume pedal I have to use an XLR to TS adaptor and it creates all kinds of noise....

Danny1969

andyg_prs said:

Actually I forgot, the CaptorX likes XLR to PA......to get into  a volume pedal I have to use an XLR to TS adaptor and it creates all kinds of noise....

You need to convert the balanced XRL to single ended first .... so XRL into mono jack cable ... not TRS .. then into volume pedal.
This is unbalanced but on such a short run will make very little difference noise wise. 

andyg_prs

I'll try, but the fairies have been moving all me adaptors again recently.......but I do recall a year or so again I was getting whirring and humming noises taking an XLR from the CaptorX to mono jack cable on the PA and I got the same kind of noise, even on a short run.....and only using XLR to XLR got rid of it.

Danny1969

Balanced XRL is great for getting rid of what's called "common mode' noise" ...... basically a proper balanced output is a differential output of the signal made twice but with opposite polarity and put on pins 2 and 3 with 1 being ground. The next device with the XRL balanced input has a differential amplifier input which only amplifies the difference between the 2 signals on pins 2 and 3. 

Any hum picked up along the way will appear on both signals  ... so will be ignored and not amplified. This is called common mode rejection. 

So balanced XRL is a great thing but you can't just feed it into a volume pedal like a normal single ended signal like guitar etc. You would need to convert it to single ended first by shorting pin 3 to ground .. this is what using an XRL to mono jack will do but unfortunately it will also defeat the common mode rejection advantage of the balanced system and any hum will be back. 

Maybe you have some earth loop noise in the system.  

andyg_prs

Thanks for the explanation.....the hum is one thing....but without XLR to XLR the CaptorX also produces this freaky whirring noise.....almost as though it's internal fan noise is being amplified down the line....

andyg_prs

Here it is https://youtube.com/shorts/WuUxMR9p2Bs?si=MBl0P7ipvBVOIywA

that was without a guitar plugged in, monitoring volume needed to be much louder and so relatively was the whine...

Danny1969

Yeah that is noise from the internal circuit and what sounds like the fan ...

That mic lead looks really cheap and the shielding could be very poor. When used a balanced  mic lead this isn't an issue as the CRM takes care of any noise that gets past the shielding onto the inner conductors. With this setup though a well shielded guitar cable coming from the Captor via a female XRL end would be a better bet. 

I think the type of volume pedal is adding noise too ... is it an active design ? 

Danny1969

The loss of level is normal when converting from balanced to unbalanced at it's half'ed in amplitude ( -6dB} 

steamabacus

@Danny1969

Any reason why using a stereo volume pedal with XLR - 2 x TS cabling in and out wouldn't work? (As a way of keeping balanced signals on input and output)

andyg_prs

I’ve tried lots of mic leads including brand new ones - sod's law is that I'd already ordered these....but I think I have a female to female jack adaptor.....so I'll see later if I have what I need to run one of my whirlwind cables from the CaptorX to the volume pedal.....but I think it's a CaptorX peculiarity as it's the whining more than a hum/buzz.

I have various volume pedals......but I think they are all active..... 

But as I say.......I think I get the noise running the CaptorX to any kind of PA unless I'm using XLR to XLR....but I'll experiment as above with and without the  volume pedal....

Danny1969

steamabacus said:

@Danny1969

Any reason why using a stereo volume pedal with XLR - 2 x TS cabling in and out wouldn't work? (As a way of keeping balanced signals on input and output)

No still wouldn't be balanced as volume pedals act as voltage potential dividers between full signal strength and ground. On full off position wiper is connected to ground, on full volume position wiper is as far from ground as the pot value  ... 500K for example. 

A balanced differential input amplifies the difference between the 2 signals which are 180 degrees out of phase, so opposite in polarity.  If pin 2 registers 2V positive then pin 3 is -2V and there's a difference of 4V between them. Now if a bit of noise hits the cable and is +1 volt in amplitude then that goes on both conductors and the difference is still 4V and thus that noise is rejected. 

There are monitor controller which will act as volume control between balanced connections but they tend to be upwards of £100 and not really designed for the foot. 

ICBM

You can retain balancing with a passive volume pedal, but you would need to custom wire it with the ground separated from the pot connections.

andyg_prs

ICBM said:

You can retain balancing with a passive volume pedal, but you would need to custom wire it with the ground separated from the pot connections.

You couldn't direct me to, or sketch out the wiring could you?... Please

ICBM

andyg_prs said:

You couldn't direct me to, or sketch out the wiring could you?... Please

Very simple - the incoming balanced signal goes to the two outer connections on the pot, and the outgoing is from the centre and the anticlockwise (the one that would normally be grounded). ie, the same as a normal volume except that the anticlockwise terminal is not grounded. The grounds should still be connected to the casing of the pedal to prevent noise.

In theory, it should be done with a dual-gang pot so the two halves of the signal are reduced symmetrically, but since the centre point is floating it actually makes no real difference.