Matrix gt800fx clipping?

I'm running an Axe FX 2 into a matrix gt800fx in stereo mode to an orange ppc212 16 ohm cab rated at 120 watts through a single speakon cable. Whenever I turn the volume of channel A to around 1 o'clock, the small red signal limit light begins to flash. To my knowledge, clipping a SS amplifier is supposed to be a very bad thing. What I fail to understand however is that the volume output that I'm getting with my band's mix isn't very loud. If anything, I'm having trouble keeping up with our other guitarist who is using an Egnater rebel 30 head. From what I've been told, this unit should be more than loud enough to play with a band, so I'm confused as to why this thing is clipping. Anyone have experience with this issue?
 
If the signal lights come on, then you're at 10% of max output.. it's not clipping and you can keep going!

However, if you *hear* clipping or something, then talk to Matrix, they're very helpful.
 
IIRC, the lights when blinking means you are -12db from clipping; solid is -6 ... I forget now that I'm typing. Perhaps go read the manual?

I have a GT1000FX into 2 2x12s and if those lights are blinking, it's pretty farggin loud ... even for me. (Solid on is too loud if there is such a thing) ;)

Where is your AXE Output set? Meaning are you sending enough signal to the Matrix?
 
I understand that the green signal light is fine and doesn't mean anything bad is happening, but my question is regarding the smaller red "signal limit" light. If that signal limit light comes on or even blinks, isn't that a bad thing? I've tried reading the manual and it was basically useless in addressing this particular issue. I should also add that my drummer is very loud, so it takes quite a bit of volume to be heard. My axe output 1 volume knob is set all the way to max.
 
Explain a bit better how you are running your GT800 - it seems like you are describing that you are running it in 2 channel (stereo) mode but only using one channel's output to the Cab IE it's a mono 120W 16 Ohm cab .... is that correct? If so, then the maximum output it will provide @16 Ohm per channel is 120 W - so basically you could turn the channel level you use to feed the cab up to 3/4 full open and turn down your Axe output rather than running it full open.

Your one point of playing volume adjustment would then be the Axe Output level knob and not the Matrix level knob(s). Running the Axe-FX output full open is putting out a very hot signal I think!

The reference Matrix led guide charts can be found on their website here

I've set things up on my Axe/Matrix combination as below:

I have a GT1000FX and my cabs are rated 200W @ 8 Ohms. I run the amp in 2 channel mode with a channel going to each cab.

I set up things so my loudest boosted preset is hitting around +4 on the VU meters in the Utility menu and not clipping the output led on the Axe. (0dB in the VU utility menu is only a marker to help visualise things when volume leveling your presets - it's not actually anywhere near 0dB at the outputs - so having peaks of +4 to +6 in them is still safe)

I call 3 o'clock position on my Axe Output level knob that feeds the Matrix as the 'absolute limit' I'd ever dare use.

With the Axe output set to 3 o'clock (my theoretical absolute) I then turn on the Matrix (it's a SS amp so no need to have your cab connected at this point unless you want to get deaf) with it's levels down and gradually bring them up until the leds do the right thing while playing as per the Matrix website charts for my cabs ratings.

For me that means I can run the red leds safely to where they are practically solid on with just the hint of pulsing and still be well within the ratings of my cabs - this equates to somewhere between 2 and 3 o'clock positions on the Matrix levels knobs - I reckon I'm putting out about 80W @ 8 Ohms per channel at those extreme Axe output level settings.

I then turn down the Axe Output level and plug the cabs into the Matrix - then I bring up the Axe output until it's loud enough .... and believe me that's well before I get anywhere near the 3 o'clock 'limit' position.
 
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Explain a bit better how you are running your GT800 - it seems like you are describing that you are running it in 2 channel (stereo) mode but only using one channel's output to the Cab IE it's a mono 120W 16 Ohm cab .... is that correct? If so, then the maximum output it will provide @16 Ohm per channel is 120 W - so basically you could turn the channel level you use to feed the cab up to 3/4 full open and turn down your Axe output rather than running it full open.

Your one point of playing volume adjustment would then be the Axe Output level knob and not the Matrix level knob(s). Running the Axe-FX output full open is putting out a very hot signal I think!

The reference Matrix led guide charts can be found on their website here

I've set things up on my Axe/Matrix combination as below:

I have a GT1000FX and my cabs are rated 200W @ 8 Ohms. I run the amp in 2 channel mode with a channel going to each cab.

I set up things so my loudest boosted preset is hitting around +4 on the VU meters in the Utility menu and not clipping the output led on the Axe. (0dB in the VU utility menu is only a marker to help visualise things when volume leveling your presets - it's not actually anywhere near 0dB at the outputs - so having peaks of +4 to +6 in them is still safe)

I call 3 o'clock position on my Axe Output level knob that feeds the Matrix as the 'absolute limit' I'd ever dare use.

With the Axe output set to 3 o'clock (my theoretical absolute) I then turn on the Matrix (it's a SS amp so no need to have your cab connected at this point unless you want to get deaf) with it's levels down and gradually bring them up until the leds do the right thing while playing as per the Matrix website charts for my cabs ratings.

For me that means I can run the red leds safely to where they are practically solid on with just the hint of pulsing and still be well within the ratings of my cabs - this equates to somewhere between 2 and 3 o'clock positions on the Matrix levels knobs - I reckon I'm putting out about 80W @ 8 Ohms per channel at those extreme Axe output level settings.

I then turn down the Axe Output level and plug the cabs into the Matrix - then I bring up the Axe output until it's loud enough .... and believe me that's well before I get anywhere near the 3 o'clock 'limit' position.

Yes, I run the matrix in stereo mode while on using on channel into a 16 ohm mono cab. Theoretically, with the matrix pushing a max of 120w into a 120w cab, is it even possible to blow the speakers? If i were to turn the output volume of the axe down while turning the volume of the matrix up, wouldn't my volume levels still technically be about the same? I basically just need to make my sound a little louder without clipping which would ultimately cook my speakers. That's what I'm going for. Another odd issue i'm facing is that my double verb clean and shiver clean are pretty close to the same volume, yet the shiver clean doesn't toggle the signal limit light while the double verb clean does. This stuff is all very new to me, so feel free to tell me if I'm being naive, I'm just very protective of my equipment and don't want to blow up my speakers.
 
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Yes, I run the matrix in stereo mode while on using on channel into a 16 ohm mono cab. Theoretically, with the matrix pushing a max of 120w into a 120w cab, is it even possible to blow the speakers? If i were to turn the output volume of the axe down while turning the volume of the matrix up, wouldn't my volume levels still technically be about the same? I basically just need to make my sound a little louder without clipping which would ultimately cook my speakers. That's what I'm going for. Another odd issue i'm facing is that my double verb clean and shiver clean are pretty close to the same volume, yet the shiver clean doesn't toggle the signal limit light while the double verb clean does.
You can (theoretically) use whatever input level setting you like on the Matrix and a lot would say run a SS amp full open - but I personally feel happier with it not right on the limit just in case - so that's why I suggested trying 3/4 open - makes for a bit of added safety in my way of thinking.

When you turn down the AxeFX and turn up the Matrix it's just putting the volume control at the AxeFX side of things. The level controls on the Matrix are input attenuators - the power amp is actually full open behind them .... so you're just moving that attenuation to the finer control of the AxeFX output knob - while the power amp is set and left alone.

The signal strength coming out an AxeFX at full output level is going to be hot as hell which might clip the input of the Matrix and also invites the prospect of noise even if the AxeFX has a good signal/noise ratio ... so I think a lower but still a healthy line level signal from the Axe to a clean (as in practically full open for clean headroom) SS amp is the better option.

If you ever got near to putting an actual 120W load into those speakers - even 100W, it would be painful to stand in front of that cab - so for a large part your ears should make you keep things within safe limits.

All my own opinion (and quite probably misuse of technical terms) of course .... but nothing's melted yet with me .... besides my eardrums maybe.

As for the DV versus Shiva thing ..... I'd say one's technically 'louder' than the other even though it might not seem so ....the signal detector in the Matrix is not encumbered with a human brain and human ears. Probably some scientific theory of 'perceived volume' out there to read ...
 
You can (theoretically) use whatever input level setting you like on the Matrix and a lot would say run a SS amp full open - but I personally feel happier with it not right on the limit just in case - so that's why I suggested trying 3/4 open - makes for a bit of added safety in my way of thinking.

When you turn down the AxeFX and turn up the Matrix it's just putting the volume control at the AxeFX side of things. The level controls on the Matrix are input attenuators - the power amp is actually full open behind them .... so you're just moving that attenuation to the finer control of the AxeFX output knob - while the power amp is set and left alone.

The signal strength coming out an AxeFX at full output level is going to be hot as hell which might clip the input of the Matrix and also invites the prospect of noise even if the AxeFX has a good signal/noise ratio ... so I think a lower but still a healthy line level signal from the Axe to a clean (as in practically full open for clean headroom) SS amp is the better option.

If you ever got near to putting an actual 120W load into those speakers - even 100W, it would be painful to stand in front of that cab - so for a large part your ears should make you keep things within safe limits.

All my own opinion (and quite probably misuse of technical terms) of course .... but nothing's melted yet with me .... besides my eardrums maybe.

As for the DV versus Shiva thing ..... I'd say one's technically 'louder' than the other even though it might not seem so ....the signal detector in the Matrix is not encumbered with a human brain and human ears. Probably some scientific theory of 'perceived volume' out there to read ...

Thank you very much for your helpful comments. I read the owners manual front to back a couple times before I even turned the amp on and didn't see anything that set my mind at ease, so thanks for "dumbing it down" for me.
 
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