Limiter

    Strange... It seems to impact the dynamics even before they hit the threshold.

    "But dignity is difficult to maintain
    stamina requires constant upkeep
    repetition is boring
    and you pay for grace."

    Well... It's true that without the option of placing it in the last step of the chain a limiter (to avoid clipping in some clean tones by cutting the peaks) has less sense, but we still could place it in the X or MOD slots.

    I can think of two reasons why a brickwall limiter would be a good idea.


    1) As a failsafe before hitting the A/D converters. Sometimes an unexpected click or pop may happen unexpectedly, and it's better to limit than hard-clip.
    2) To increase output S/N and lop off clicky transients in general. Plus, one can't assume that guitar is necessarily the only type of musical signal that will be run through it.


    Of course, a (ideally adjustable) amount of lookahead should be on tap, and would introduce a certain amount of latency in the signal; but really, I'd love to see a L1 Ultramaximizer type of effect. If it's useful in the studio, it's useful in the KPA both as a safety item and as a creative tool.


    -djh

    I don't see the point of a limiter in the guitar chain either. In 25 years of audio engineering, I don't think I've ever slapped a limiter on a guitar channel....


    There's absolutely no need to hit the DA so close to 0 dBFS for s/n, or other reasons. Stay safe and sound better! It's bad enough that mastering pushes everything to the limits (and back!) these days.


    That said, isn't there already soft limiting in place on both DA and AD stage in the Kemper to avoid nasty clipping anyway?

    Quote from dhodgson

    1) As a failsafe before hitting the A/D converters. Sometimes an unexpected click or pop may happen unexpectedly, and it's better to limit than hard-clip.

    The only thing that can clip before the A\D converters is the input. Once you strum as hard as you can, and the red LED is not steady, you should be OK


    :)

    Quote from dhodgson

    I can think of two reasons why a brickwall limiter would be a good idea.


    Quote from dhodgson

    1) As a failsafe before hitting the A/D converters. Sometimes an unexpected click or pop may happen unexpectedly, and it's better to limit than hard-clip.
    2) To increase output S/N and lop off clicky transients in general. Plus, one can't assume that guitar is necessarily the only type of musical signal that will be run through it.


    This is far too tecky for me :)


    This is a guitar amp, not a mixing desk or mastering tool.
    A guitar amp prevents overshoots in a natural way by its distortion.
    In addition we perform a soft clipping on input and output.
    No room for latency by a lookahead limiter, as there is no problem to solve.

    Whoops, I meant to say "1) As a failsafe before hitting the D/A converters." That should clear up my thinking there, d'oh! :huh:


    In the end it's all software, of course. And as a feature that would be leveraging existing code with little development cost at stake, well... I don't think I'm the only one who would find this useful. Same goes for the Hass effect mentioned on another thread, it's a cheap effect.


    -djh


    We carefully chose the features and effects, and the way it is implemented.
    The reason for this is, that we want to continue this for the next decade or so, without changing things afterwards.
    Even if the majorities opinion, we double check the applications, when we have doubts.


    My conclusion about the limiter: a limiter with look-ahead is usually used in mastering or other situations, where latency is no issue. I have not heard of any realtime (!) hardware device, that use limiters for avoiding clipping. Soft clipping is the way to go by good reasons.


    About the Haas effect: there is one shortcoming and two side effect:
    - When mixed to mono you get a nasty comb filter
    - Due to the Haas effect the signal is virtually panned to one side
    - The Haas effect is not noticable in bigger live venues.


    I read 10 different articles on the web about the application of the Haas effect. Only two mentioned some of these issues.
    Thus must conclude that the application of the Haas effect is often spread by people that don't have enough overview about the technical aspects of audio processing.
    I can think of better ways to create a stereo or doubling effect than using just a short delay. I will soon try a new type of effect that will avoid the short comings.


    Surprisingly enough, i think i'm convinced.
    Not sure i agree with calling everyone who recommends the Haas effect 'uninformed', but the KPA is primarily a mono device and i understand why it needs to stay mono compatible. :thumbup:


    Regardless, the decade update time-frame is very good news!

    "But dignity is difficult to maintain
    stamina requires constant upkeep
    repetition is boring
    and you pay for grace."

    Quote from ckemper


    My conclusion about the limiter: a limiter with look-ahead is usually used in mastering or other situations, where latency is no issue. I have not heard of any realtime (!) hardware device, that use limiters for avoiding clipping. Soft clipping is the way to go by good reasons.


    From the Behringer Ultra-Curve Pro 24/96 Manual:
    "The LIMITER function is always active and cannot be switched off. It is also active in bypass mode, however, only works to a limit value of 0dB, so as to avoid digital distortion occurring on the outputs."


    So, there's one example of a real-time hardware device that avoids clipping using limiters, Chris - and in fact, it's Always On (!) Anyway. I don't want to beat the Hass effect thing to death, but I could quote from a good half dozen mix-engineering books on my bookshelf on this topic, email me and I'll be happy to send you links. I made the production case for the effect in more depth on the Hass thread, but if you're not convinced, what can I say? If I grumble, that doesn't mean I'm not tickled by your amp in nearly all respects - surely you know that! :D


    -djh

    If the Behringer can generate digital distortion, it means that its processor can manage small words only. It probably uses a 8- or 16- bit processor.


    It's impossible to make the KPA digitally distort, it can handle much higher numbers. I had made some maths time ago, now I've forgotten the results but believe me, the only things that can distort in the KPA are the analogic sections (i.e. before the A\D conversion and after the D\A conversion).
    IOW, the KPA's digital headroom is - for practical applications - virtually infinite. :thumbup:

    Great. Having a limiter always on on a mastering hardware is fine. I wonder what the latency is. No statemend found there.
    Having a limiter as a whatch dog on inputs and outputs of a guitar amp is not cool at all, especially with added latency.


    A soft cipping on the input has the advantage, that the input can be softly overdriven, even though it's digital. Not possible with a limiter on the software side.


    I give you a Haas answer on that other thread.