" Transpose EFX " [ a.k.a Digital Capo ] ...... latency is really noticeable .... is this a known issue (?)

    Hey all !


    I was reading the manual today [ I know :) ] and came across the reference to the " Transpose " EFX - in particular it mentioned the [ brilliant ] idea of using it as a " Digital Capo " .


    How good is this I thought !!!


    Got home, pulled up a rig, inserted the Transpose EFX into Slot 1 and set it to +2 ...... which is UP 1 tone.


    Sounds perfect except that there is quite noticeable latency on the Transposition - my guess is something in the order of 20ms or more ...... way too much latency to make it useable as a " Digital Capo " for basic things like rhythm strumming etc.....


    Im using the latest firmware.


    If the Transpose EFX worked with the same [ in-practice-unnoticeable ] latency as the rest of the Kemper, then this would be an amazing feature - a real [useable] Digital Capo :)


    So ..... is this a known problem / bug / firmware-fixable issue ?


    Ben

    Hey,


    I hear a little latency, too. Same goes for the Octaver, etc. But for my taste it's still useful.
    Make sure you don't hear your dry guitar sound, e.g. by using headphones. Otherwise you will always be hearing the latency, because you hear two sounds that are slighty off. And our brain is quite good at recognizing such tiny differences ;) I think if you only hear one of these sounds, you will get used to it.


    Just my 2 cents, Stefan

    My biggest fear is when I die my wife will sell my guitars for what I told her they cost.

    I don't think I have any issues with the transpose effect... Did have an issue with a harmoniser or chromatic pitch at one point (as they have 2 voice options; 1 & 2) and perhaps I am not adjusting those correctly....


    But as for latency with the transpose... Nada.


    Check (if there is the option of...) 'mix' and set to 100% and also recognise you will hear the strings of your guitar audibly as well as the transposed signal (unless you're playing LOUD!) and this is sometimes off-putting for myself - could be construde as latency?!

    CURRENT:
    (FLOOR) Kemper Remote w/ Mission exp + EB VP
    (RACK) Kemper PowerRack

    My band plays Smell Like Teen Spirit and I decided to drop it half a step like the original. I can notice the latency when playing this song it's a little off putting. I use IEMs so I don't hear the normal guitar I can only hear the Kemper output. It's strange because we also play a song which is drop B which again i use the transpose effect for this but the latency is not as noticeble even though it's dropped by -3 instead of -1 like the nirvana song??

    Hey all !


    Thanks for all the responses.


    I tried and tested this with headphones on - and they were LOUD - no way on earth I could also be hearing the electric-strings-acoustically.


    Also, unless I can't see it, there is no MIX control on Transpose - MIX or no MIX isn't a fix anyway as that doesn't. "fix " the issue of strumming the strings with your right-hand and hearing the sound "later".


    Simple test.


    - Pull up your favorite clean tone
    - disengage / delete all EFX
    - insert the TRANSPOSE into any Slot - say Slot 1
    - Set it to +2 [ 2 x semitones / 1 full tone ]
    - turn you speaker off
    - plug in your headphones
    - turn the volume up loud on your headphones so you can't hear the electric-strings-acoustically
    - play a guitar rythmn like its an acoustic guitar. [ or anything else you want ]
    - report back what you hear


    There will only be 2 possible outcomes


    -> either my KPA is faulty ?


    or


    -> you will clearly hear the latency-effect on the Transpose ?


    For anything other than slow-playing or ambient guitar its just *not* quick enough to be a "Digital Capo".


    If the Kemper processed its raw-amp tones with this much latency, no one would ever buy one.


    FIX COMMENT / THOUGHT


    The Kemper does its magic through AD / DA conversion.


    As always, this AD / DA conversion has a very-small latency - and the rest of the Kemper also adds a bit of latency - in reality / practice, however, this latency is irrelevant / unnoticeable / never an issue


    Even if TRANSPOSE requires more " Kemper processing juice " than say the guitar tone processing itself, it should still work at the same [low unnoticeable] latency with the only [possible] negative-side-effect being that it may only be able to run with, say, for example, 3 other slot efx as opposed to all the other slot efx


    So even if the TRANSPOSE is a processor / juice "hog" there is no reason that it shouldn't still work with the same [constant] low-latency as the core of the KPA ...... even if it were to limit the processing available for the other possible slots.


    Of course, if it has nothing to do with how the KPA handles / shares / manages its finite processing power, then it is simply a firmware/coding issue that should be easily fixed especially


    BIG HINT - Given that Raoul has found that different TRANSPOSE levels / steps result in different latency effects even though the KPA is designed to operate at constant latency tells and confirms to me it is a software / firmware fixable issue.


    Ben

    Edited 3 times, last by benifin ().

    Quote from benifin

    ...... latency is really noticeable .... is this a known issue (?)']Even if TRANSPOSE requires more " Kemper processing juice " than say the guitar tone processing itself, it should still work at the same [low unnoticeable] latency with the only [possible] negative-side-effect being that it may only be able to run with, say, for example

    , 3 other slot efx as opposed to all the other slot efx


    So even if the TRANSPOSE is a processor / juice "hog" there is no reason that it shouldn't still work with the same [constant] low-latency as the core of the KPA ...... even if it were to limit the processing available for the other possible slots.


    Not quite. Any pitch shifting HAS to add a bit of latency, because the Kemper needs to take some time to process what you're playing and produce the pitch-shifted signal. Low notes typically take a little longer to detect than high notes as well, just because the actual sine wave for a low note is oscillating slower and thus takes longer to give the Kemper a few complete waves to examine. I'm pretty sure chords actually add more latency than single notes as well because you're increasing the amount of detection time the Kemper needs to establish what it is you're playing.

    I had some issue with this. I tried putting it in slots X and 4, and hitting the "Smooth Chords" button also. I don't remember where I ended up, but I got it to sound decent enough to use. I use it on two songs for both single note (with slide) and chords. One is down a step, one is up a step and a half.

    Learn to Swim

    Always use it in the first slot! (that is, unless you like it in another one 8) )
    It's been a while since I last used transpose but I remember it to be very very fast. I'll have to check again....


    To OP: How did you measure those 20 ms or more? I hope you did not JUST guess...

    I use transpose on several songs live, Pantera, Van Halen, etc and notice an ever so slight delay if I'm really listening for it (I use -1 and -2 semitones only). To me it tracks better than any other unit I've tried. Not enough to worry about live, maybe in a studio I'd actually set a guitar up properly. I always use it in slot A and never on a clean tone.

    I use it in gigs to go up a semi for a few tunes. Works pretty well for me.
    The only problem I've ever had with it is forgetting to charge slot for the next song which didn't need the transpose.
    Our bass player thought it was his problem as we started the next song...(a slow blues) and managed to re-tune all 4 of his strings before I realised it was me and gave him a sickly grin!
    We laughed about it afterwards.
    Our singer didn't even notice haha!

    I notice the latency, when it's around 4 steps up it almost takes me off-beat when I play and sing because I tend to correct my arpeggios to keep things together LOL.
    20 ms seem a lot to me too tho.

    I'm using the Transpose as well and i too notice the latency.
    Nevertheless this feature saves me from bringing a second or third guitar with different tuning to a gig. So i am willing get along with the latency.
    I just try to focus on the band.


    My understanding of the latency is this:
    The Kemper records your playing and then gives it back with a different speed. So when you need to have a full-tone up, it will just give you back the recording at higher speed. This will result in a higher pitch.
    Can anyone confirm or correct this?