Scene changes - amp channels and audio gaps?

Gap & istant are different things. Most real amps could be seamless, but not istant, some have a gap. For a devise to be gapless you should run two parallel circuit and "mix" them as fast as possible without popping, clipping, chirping or volume loss... be it analog or digital. In analog you need parallel channels (there are almost no modern amp with parallel channel, they simply add gain stages). In digital you have parallel processing. If an amp run 40% CPU and effect 30% (70% total) to have perfect switching you have to run a parallel amp (+40%, so total 110%!), wait for stabilty, then fade out first amp while second amp fade in. In a shitty amp modeling with 5% CPU they could run as many istance as needed. Maybe they stabilise faster, in a few ms. But now we know why many digital device deserve the "digital sounding and lifeless" title...
 
Yeah, the "gap" sucks. I find myself having to set up a preset and use the same "channel" and amp for the scenes...I have to use a different channel and amp for the clean sound of course (as opposed to crunch and lead)...and coming out of clean to do a lead break kinda sucks.

My "real" amps always were seamless as was my Helix.
My real amps (there were many over the decades) included ones like the Bogner Ecstasy, Marshall TSL, and my current Mesa TC 50.

Anyway...it would be nice to be able to use different channels in a preset with different amps without a gap.
My preset (which is the only one I use with 6 scenes) runs at around 63% CPU useage.

IF we had the option to have TWO amp blocks (which would help get rid of that gap I would think)...wouldn't someone like me be able to squeeze that in CPU-wise?
 
The way I see it: With the FM3, you've got a surprising amount of versatility in a preset - with channels & controllers you can run more variants of the same effects than any floor modeler I'm aware of, and I am very familiar with both QC and Helix - but the cost of utilization is in scene/channel gaps.

It's a trade off, but scene change gaps are my biggest disappointment with the FM3. You CAN absolutely work around it, but you're options of effects/amps are limited to methods/models that allow for the smallest gaps. Spillover between 2 reverbs/delays or even 2 settings on the same reverb/delay don't generally feel natural, either. For my use, I've been able to minimize gaps between channels enough to make it passable in a band context, but if I'm playing solo, I don't usually bother trying with channels as it's pretty blatant.
 
It would be great if processing power were so cheap, cool, and small that we could offer two complete engines in each product for switching that could actually crossfade. Until that future arrives, you can choose to let any very small gaps bother you, or not. To put things in perspective, there are many, including serious pros like like Dweezil, the Edge, Devin Townsend, Chris Traynor, Trevor Rabin, Adrian Belew and many others, who switch not channels in the middle of a song, but PRESETS, and no one ever notices (or if they do, they don't care.)
 
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Anyway...it would be nice to be able to use different channels in a preset with different amps without a gap.
My preset (which is the only one I use with 6 scenes) runs at around 63% CPU useage.
Doesn't matter. Amp sim runs in a different core not shown in the CPU meter. Wild guess, but chances are that CPU usage of an additional amp block running in the FX core would spend far more than 50% of the CPU.
 
It would be great if processing power were so cheap, cool, and small that we could offer two complete engines in each product for switching that could actually crossfade.
This.

You actually offer the Axe FX which is capable of this, so the option is on the table for those who absolutelly need it. It was like this in the analog age, and it is still today in the digital age: for perfect seamless switching, you need to pay for 2x the power. 50% of that power will be idle 99% of the time.
 
Fire up your favorite flesh-and-blood tube amp. Let a chord ring out, and change channels. Listen for the gap. ;) It’ll likely be worse than the FM3.

You get a 15-day return policy with the FM3. Try it out. You’ll know quickly whether it’s an issue for you.

Although most amps have some gap to prevent popping when changing channels, the vast majority of amps I've played have less of a gap than the FM3 does when changing scenes that also change amp blocks. Sometimes it even feels like there's a latency between hitting the new scene and it beginning the change which could be adding to that impression. The Axe was much faster.
 
I can work with the FM3 but I will drop my two cents here. The gap between presets is unworkable for me. The gap between scenes is also difficult to minimize. I find as long as its turning something on or off its ok. If you switch to another channel, even with the same amp and different settings there is a gap. This has been a disappointment for me. I can still make it work. Scene controllers work well but there are not enough of them.

I am coming off using Rocktron preamps and a GSP1101 in previous rigs. The Rocktrons i had offered no spillover but the switching was faster than the FM3. The GSP1101 has spillover and no gaps. Switching on the 1101 is fast enough that it seems instant. I knew going into the FM3 that preset changes were slow. I was sold on the scenes being faster. They are, but I didn't expect to need to compromise and find workarounds. For switching between a clean tone and a dirty one I have a parallel path with an eq block on when switching to clean.. This makes the gap between the two amp channels less noticeable.

I am happy with the FM3 but I do wish there was faster switching. I bought it for recording. I liked it into the loop of my Marshall so much I want to work it into the live rig too.
 
Have you ever explored creating a (very) clean amp from a compressor and an EQ block into a Cab? It works great!
 
To put things in perspective, there are many, including serious pros like like Dweezil, the Edge, Devin Townsend, Chris Traynor, Trevor Rabin, Adrian Belew and many others, who switch not channels in the middle of a song, but PRESETS, and no one ever notices (or if they do, they don't care.)
Yeah, what do they know? :rolleyes: Seriously people. The FM3 has the ability to make multiple changes with the press of one footswitch and there's complaints that it takes too long? I'm usually the lone guitar player on our team in a P&W environment, lots of delay and ambient tones, and it really doesn't take much effort to figure out when to change scenes or presets. Instances where there's a need to be seamless, I use control switches. So many tools and options to get hung up over one detail.
 
Although most amps have some gap to prevent popping when changing channels, the vast majority of amps I've played have less of a gap than the FM3 does when changing scenes that also change amp blocks. Sometimes it even feels like there's a latency between hitting the new scene and it beginning the change which could be adding to that impression. The Axe was much faster.
That "latency" is probably coming from a footswitch that has a hold function. In that case, the tap function doesn't trigger until you release the switch.
 
Some very useful and valid points here. As musicians we will all have slightly different requirements I’m sure. Yes Devin Townsend switches between presets but he tends to have several musicians with him and often some form of backing track. (I am a huge fan of Devin so no disrespect intended.) Being in a three piece it’s a little harder to cover up changes.
Ive recently shifted to IEM and wanted to condense my guitar rig (as most of us do). Like I’ve said before there is no doubt that Fractal can achieve magnificent tones but so can a Kemper (with decent profiles of course) which has seamless switching and spillover. That being said the UI is a little dated and the Fractal is a little more appealing with the incorporated Audio Interface.
The way I write my music often involves some sort of delay on a clean section which will switch to a big thick Crunch tone. It’s more the spillover I’m focusing on, if the FM3 has the ability to allow delays to bleed in the channel change on an amp (within one preset) to mask the channel change then happy days.
It is the abrupt cut off of ambient effects from one amp sound to another that is rather jarring to my ears and often sounds a little amateur in my opinion.
I don’t want gear to get in the way of creativity or performance that’s all. I want to focus on what’s most important and that’s generally juggling guitar and vocal duties which is enough to think about.
 
...if the FM3 has the ability to allow delays to bleed in the channel change on an amp (within one preset) to mask the channel change then happy days.
It is the abrupt cut off of ambient effects from one amp sound to another that is rather jarring to my ears and often sounds a little amateur in my opinion.
I don’t want gear to get in the way of creativity or performance that’s all. I want to focus on what’s most important and that’s generally juggling guitar and vocal duties which is enough to think about.
If you just want the delay to ring out after it's bypassed, set its bypass mode to Mute FX In.

If you want the delay ring out while another delay kicks in, consider adding a second Delay block.
 
Read the section on Spillover in the manual. That covers spillover between presets, and that's needed to accomplish that.

While preset switching is fast on the III, changing sounds through scenes (within a single preset) is often faster. And spillover between is largely automatic. The section in the manual about preset spillover and the global Spillover parameter do not apply to scenes. As Rex writes, the Bypass Mode parameter is most important here.

Regarding switching channels: almost everything happens almost instantly, except amp channel switching. That requires a bit of time, no way around that, due to the way things are modeled. Just time the switching well, or let reverb or delay ring out ................................................
 
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