• We would like to remind our members that this is a privately owned, run and supported forum. You are here at the invitation and discretion of the owners. As such, rules and standards of conduct will be applied that help keep this forum functioning as the owners desire. These include, but are not limited to, removing content and even access to the forum.

    Please give yourself a refresher on the forum rules you agreed to follow when you signed up.

Amp Block - Boost Switch - Level Control

GreatGreen

Power User
In the Amp block, the Boost switch is locked at a 12db boost if engaged. I'm sure a lot of people really like this parameter exactly as it is, but personally, I and a few others I've spoken with have found 12db to be just a bit much. Personally, when I boost I always go for somewhere around 8 or 9db of boost, and to do this I always find myself having to either add a Filter block with a flat boost in front of the amp, or heavily adjust the input trim, then map it to an IA switch.

I wish the Advanced tab of the Amp block featured a Boost Level parameter that would allow the user to control exactly how much boost is applied when the Boost Switch is engaged, much like how the Bright Cap parameter corresponds to the Bright Switch in the Amp block.
 

billmeedog

Inspired
That is what the input trim in the amp block does.
I'm not sure what the input-trim has to do with the amount (in db) of boost when the BOOST is engaged? Am I missing something here? I think the OP has a great idea here, unless there's a workaround (which I'm not aware of) that is NOT CPU-intensive?

Bill
 

barhrecords

Axe-Master
I'm not sure what the input-trim has to do with the amount (in db) of boost when the BOOST is engaged? Am I missing something here? I think the OP has a great idea here, unless there's a workaround (which I'm not aware of) that is NOT CPU-intensive?

Bill
The input trim can be used as a finer grained boost. In an X/Y.

Not exactly the same as a variable boost would be though in regards to creating a preset.

Richard
 

GreatGreen

Power User
That is what the input trim in the amp block does.
Well, kind of.

As far as I can tell, the Amp Block's Input Trim control is designed as a "set and forget" type of parameter you use to tell the Amp Block how loud your guitar should initially be because unlike a real amp, the input of the Axe-Fx (thanks to you always setting the instrument input level as 'as loud as it can be without clipping much') always sees all guitars as roughly the same volume. So in other words, the Axe-Fx always sees every guitar's signal as "right around 0db" or whatever it is, and the Input Trim is designed as a compensator for this fact, to let you simulate how relatively strong or weak your guitar's pickups are.

Using the Input Trim as switchable boost is really a kind of ghetto-rigging scenario. It works, sure! But you have to kind of make it work using a really cumbersome, round-about method.


By contrast, the Boost Switch is designed from the ground up as something built to be turned on and off as you need, well... a boost! It is effectively a clean boost pedal in front of the amp, and I simply think it would be really useful to put a volume knob on it. :)
 

DrewA

Inspired
Isn't the boost switch simply a null filter with it's gain set to 12dB? Couldn't you just add a filter, and set the gain where you want, or assign it to a controller and set the min/max values for the range you needed? Just an idea.
 

AdamCook

Power User
Isn't the boost switch simply a null filter with it's gain set to 12dB? Couldn't you just add a filter, and set the gain where you want, or assign it to a controller and set the min/max values for the range you needed? Just an idea.
This is exactly what to do except you can skip adding a filter. As Javajunkie said, just use the Input Trim in the Advanced page of the Amp block. Assign that to a controller.

You might want to convert the Input Trim parameter to dB if you're used to thinking of it that way. As a rule of thumb, every 2x multiplier = +6dB boost.

In other words, Input Trim = 4.0 produces a +12dB boost.

Here's a handy calculator:
dB calculate
 

javajunkie

Moderator
Moderator
Well, kind of.

As far as I can tell, the Amp Block's Input Trim control is designed as a "set and forget" type of parameter you use to tell the Amp Block how loud your guitar should initially be because unlike a real amp, the input of the Axe-Fx (thanks to you always setting the instrument input level as 'as loud as it can be without clipping much') always sees all guitars as roughly the same volume. So in other words, the Axe-Fx always sees every guitar's signal as "right around 0db" or whatever it is, and the Input Trim is designed as a compensator for this fact, to let you simulate how relatively strong or weak your guitar's pickups are.

Using the Input Trim as switchable boost is really a kind of ghetto-rigging scenario. It works, sure! But you have to kind of make it work using a really cumbersome, round-about method.


By contrast, the Boost Switch is designed from the ground up as something built to be turned on and off as you need, well... a boost! It is effectively a clean boost pedal in front of the amp, and I simply think it would be really useful to put a volume knob on it. :)
The boost switch and the input trim do EXACTLY the same thing. The increase the input level into the amp block nothing more. The input trim make it controllable. In other words, it does EXACTLY what you are asking. It is not a set and forget parameter. You can assign a modifier to it.


The input trim works on multiple basis so to get a 12db boost I believe you would set it to 4. I need to confirm that.


About the instrument input level.
The instrument input level (when set as suggested) give the highest SNR to the AD converters. This often times means a boost of the signal to the converters. After the AD conversion the axefx compensates by cutting as much as was boosted. This gives you a signal level that is equal to what your guitar puts out (in other words, the same level as if you had plugged into a real amp).
 

DrewA

Inspired
This is exactly what to do except you can skip adding a filter. As Javajunkie said, just use the Input Trim in the Advanced page of the Amp block. Assign that to a controller.

You might want to convert the Input Trim parameter to dB if you're used to thinking of it that way. As a rule of thumb, every 2x multiplier = +6dB boost.

In other words, Input Trim = 4.0 produces a +12dB boost.

Here's a handy calculator:
dB calculate
Good to know. I'm using an Axe first generation, so setting a null filter block set to in front of the amp seems to be roughly equivalent. I'm actually learning a lot about the II by reading these forums!
 

billmeedog

Inspired
Variable-Boost Implementation...

The boost switch and the input trim do EXACTLY the same thing. The increase the input level into the amp block nothing more. The input trim make it controllable. In other words, it does EXACTLY what you are asking. It is not a set and forget parameter. You can assign a modifier to it.
JavaJunkie,

I guess I'm somewhere in the middle of this discussion/argument...IOW, I think the input-trim/controller option is far from a "ghetto-rigged" workaround - LOL

However, I still think the OP brings up a valid point/idea...Even though there's a perfectly acceptable way to implement a variable-boost, that doesn't seem like a good enough reason to exclude the idea of creating a Boost-Level parameter on the Boost-function in a future firmware-release (unless there is some hardware or software limitation that I'm not aware of which would prevent such an implementation???) Then there could be two ways of assigning a variable-boost, (I know which method I'd be more inclined to use ;) ) and I'm sure that wouldn't be the only tone/preset creating function in the Axe-FX II which contained "designed-redundancy" - LOL!

About the instrument input level.
The instrument input level (when set as suggested) give the highest SNR to the AD converters. This often times means a boost of the signal to the converters. After the AD conversion the axefx compensates by cutting as much as was boosted. This gives you a signal level that is equal to what your guitar puts out (in other words, the same level as if you had plugged into a real amp).
Thank you for this explanation...that is very valuable and interesting info!

Bill
 
Top Bottom