Mute is not 100% silent

I've tried using the Mute On-Off feature on my GM40 by sending MIDI CC 9 with value 0 which mutes the volume, however even though subtle I can still hear the amp slightly if I crank the Master Volume at 20W/40W settings. Anyone else have the same behavior or can try it out? It´s not a big deal - I actually thought it muted the amp 100% until I changed the Power Soak from 1W to 20W and increased the Master Volume past 12 o'clock - that´s when I heard the amp slightly through my cab even though it´s supposed to be muted.

I've also noticed a bleed through tho if I've my h9 in the effects loop and effects loop off I can still hear say a faint delay effect that the h9 is programmed to deliver.

j200george wrote:I've also noticed a bleed through tho if I've my h9 in the effects loop and effects loop off I can still hear say a faint delay effect that the h9 is programmed to deliver.

I ran some tests today by connecting my H9 to the effects loop and it worked perfectly. I removed all the amps ambient effects such as reverb and delay and just had the H9 in the FX Loop. When FX Loop was on, the gorgeous H9 effects came through just as expected, when the amps FX Loop was turned off, no trace of the H9 that I could hear.

The issue I'm describing above was just when the fx loop was disengaged. Behind the main signal I could still hear some dual delay sounds in response to my playing. Fx loop off, h9 in effects loop and a faint signal from it.

Some funny stuff going on. Seemed that no matter what setting the amp effects loop was on the effects were stil playing. Realised late this evening that the WMI connection was dropping so when in fact I thought on the iPad that I was disengaging the effects loop it was in fact at the amp still on.

I'm not reacting to various issues until I'm more familiar with the amp. Some weird stuff going on though which I'll try to articulate over the coming days.

Not sure what the GMD40 will say but I'm sure it will be a similar circuit configuration to the GM36.  In the GM36 manual it says this about the Volume control:

H&K GM36 Manual wrote:8 Volume: Use the Volume knob to adjust preset levels and adjust their relative balance to other presets.  Heads Up: Unlike a conventional Volume control, this knob does not bring the level all the way down; it merely boosts or cuts the given level.  The 12 o’clock position is the best starting point for adjusting volume.

That's the way we GM36 users have always used it.  The Volume control is only to balance voices against each other, the Master Volume sets the overall level, (and of course the Master Volume is not under external control).  The Volume control actually has a 2k2 resistor in series with it preventing it from being fully zeroed.  This may be for stability reasons, it's in a complex feedback loop around an opamp, so it doesn't surprise me to find it leaves you with a very low signal.

If the GM guys want to mute the amp then we use the Power Soak Off setting, (or the Standby switch if it's for a long time ).

Hmmm. If I'm playing a piece that calls for say, clean, dry guitar, i.e. No verb or delay, it's not ideal if you can hear a delay in the signal. That's surely not normal. I'm still getting familiar with the amp and I've got an es-8 in the chain vonnted via the 4 cable method so I've got some checking and faulting to do next. Not convinced things are operating as they should via the es-8. I will get back to basics and see where we are later today.

Master, stand by etc are all fine but scrutinizong the MIDI capabilities there's a "mute" function, which I figured would mute the amp from my pedalboard but there's still some "bleed" going on, at least with my amp. It's not an issue for me but figured I'd ask if it's my amp or a feature of the GM40.

That's interesting MLordin.  Are you meaning that the source of your MIDI functions is in the GMD40 manual?  Looking at the GM36 manual, (sorry but the GM36 is all I have to go with as a reference), I found the following:

GM36 Manual wrote:Mute On-Off. On status remains active until the amp channel is changed, the volume parameter is changed or the amp is re-started

This suggests to me that what you have there is as I suspected, the Mute function is simply setting the Volume to 0, which we are pretty sure will not remove the signal completely.  The hint is that the mute is lifted once the Volume is adjusted in any way.  This is the way the digital rotary controls all work in the GMs as I'm sure you have spotted.  The value they are set to by MIDI is probably at odds with the value the knob is indicating on its dial.  This isn't a conflict, just how the controls actually work.  As soon as the system senses a change in the setting as the control is rotated, it ditches the MIDI setting for that control and flips over to the value the knob is indicating.  If the Volume affects the Mute like that it is a pretty strong sign that muting is being done via the Volume control.

Could you possibly get away with using Controller Number 30 with a value of 0?  That should set the Power Soak to silent and mute the amp fully.  The PS has 5 sectors in its range of values and I have something in my memory that suggests the sectors may have had unusual ranges because of that.  You'll be able to find out legal values pretty easily by trial and error, any value within the range is valid.

The GM40 manual states the same as you wrote above regarding Mute On/Off, and your conclusion seems reasonable, that it's connected/related to the volume pot. I will do some further experiments, but as I mentioned earlier, not a problem but a bit surprising at first glance. Using the Power Soak settings using CC 30/0 will probably do the complete mute trick - thanks for the tip!

And while I have your attention, what's the difference between hard and soft volume/gain - again looking at the Midi implementation table?

Cheers!

Ran some quick tests comparing the Midi Mute function vs. turning the volume to zero. Turning the mute feature On and Off (Midi CC 9) is actually significantly more quiet than just turning the volume down to zero. I didn´t try setting the Power Soak to "0" since I am and will be using the global Power Soak setting depending on "venue" once I have everything ironed out but confident it would totally kill the sound just as it does when pressing the no-speaker Power Soak button.

As for the Volume Soft vs. Hard (Midi CC 7 vs. 57) I believe soft means a CC value of 127 will be 100% of what the preset volume setting is, whereas hard seems to be equivalent to cranking the volume knob to it´s full position independent of the volume setting in the preset.

FYI - I ran some tests today by connecting my H9 to the effects loop and it worked perfectly! I disabled all the amps ambient effects such as reverb and delay and just had the H9 in the FX Loop. When the FX Loop was on the gorgeous H9 effects came through just as expected, when the amps FX Loop was turned off, no trace (bleed) of the H9 that I could hear and I cranked the master volume to the agony of my family just in case

Sorry, it took a while to find what I wanted re the Hard/Soft volume and I wanted to make sure it would be clear.  This is a direct quote from the H&K "Blog Of Tone".

H&K wrote:*Heads-up: “Soft” for controller numbers 07 (Volume) and 20 (Gain) refers to the softening of the change in value once you move the expression pedal. This helps to avoid abrupt volume changes in case of a remarkably large difference between the value of the controlled parameter stored in the preset and the expression pedal’s starting position. However, should you choose to use such abrupt volume changes, e.g. as a stylistic device, you can do so by assigning controller numbers 56 (Gain) and 75 (Volume) instead. These are referred to as “hard”.

It's the same control being tweaked for both Hard and Soft, Soft just has a more gradual sliding effect on the control's internal value when it is changed.

bordonbert wrote:Sorry, it took a while to find what I wanted re the Hard/Soft volume and I wanted to make sure it would be clear.  This is a direct quote from the H&K "Blog Of Tone".

H&K wrote:*Heads-up: “Soft” for controller numbers 07 (Volume) and 20 (Gain) refers to the softening of the change in value once you move the expression pedal. This helps to avoid abrupt volume changes in case of a remarkably large difference between the value of the controlled parameter stored in the preset and the expression pedal’s starting position. However, should you choose to use such abrupt volume changes, e.g. as a stylistic device, you can do so by assigning controller numbers 56 (Gain) and 75 (Volume) instead. These are referred to as “hard”.

It's the same control being tweaked for both Hard and Soft, Soft just has a more gradual sliding effect on the control's internal value when it is changed.

Thanks for the info and clarification - makes sense