Hello out there, my first post. I'm a newbie Kemper-er - bought mine just before Christmas. It's not working out like I hoped, so perhaps I'm doing something wrong (or lots of things wrong!). Here are some problems:
1. Latency - the manual says 3.5mS. If I take my guitar signal and split it with an analogue splitter pedal, then route one split through the Kemper and then into one input of my Apogee recording interface (connected to Logic on my Mac with a USB port), and the other split directly to the other Apogee input... ...the Kemper split records about 3mS late relative to the direct-to-Apogee split. Btw, this is with EVERYTHING turned off on the Kemper (no FX, no amp, no cab etc.). I can feel this latency, even with the guitar plugged directly into the Kemper and monitoring directly out of the Kemper with headphones. It feels like the Kemper is dragging (and again, this is with everything switched off). If I go one step further and monitor using the Apogee using its direct monitoring mode, I'm probably adding another 1-2mS just due to the Apogee convertors, therefore total latency is ~5mS and this, to me, starts to be a problem. Further, I wonder about the latency when you switch on amps and cabs. There is a difference between "physical onset" when the sound starts rising from digital silence and "perceptual attack" when you notice the attack of the sound. Latency often (always??) seems to be measured using physical onset - but when I start playing the Kemper (again directly monitoring with headphones plugged into the Kemper) it constantly seems to be dragging. Perhaps point 2 below has something to do with this as well.
2. Lack of attack transient - this is particularly a problem on distorted sound profiles. It makes it very difficult to play in time accurately when you can't hear the beginnings of the notes. Real amps don't seem to cut the transient off: they "thwack" even with loads of gain. I've experimented with the "Pick" parameter: to me it just sounds digi. Why weren't the profiles done properly in the first place?
3. Middly, flat sound - the upper harmonics seem to be missing / inadequate. It's hard to describe, but it's almost like the profile has too much proximity effect and / or the bass was turned up way too much on the amp and / or... ...well, I don't know, but it doesn't sound (to me) like a real amp. Often what seems to happen is that there's a burst of upper frequency energy at the start of the sound, but it fades away very rapidly and you're left with 500Hz and below sustaining (check it out on a frequency analyser). Real amps don't seem to do this in the same way.
4. Distorted sounds aren't very good - I will I'm sure be criticised for this - it's very subjective! But is it? To me, every Kemper overdriven / distorted profile I've heard sounds somehow "digi", metallic (and middly and flat too) and just not very convincing.
Any and all input appreciated!
Thanks in advance.
Question: it possible to improve Kemper's latency performance?
And he's some data as background.
I did some tests, using a Logic Klopfgeist click recorded onto my old Roland VS2480. This, if you like, was the "Control Click". I then bounced the CC using various routings to test the latency thereof. Results obtained by really zooming in on the waveform and measuring are as follows:
1. Out of VS2480 headphone output, back into VS2480 input. Result: 1.67mS delay (this is the "inherent" delay of one loop through the VS2480, obviously including it's DAC /ADC converter cycle, which is what you get when you record and monitor with this device).
2. Out of VS2480 master output, back into VS2480 input. Result: 1.67mS delay i.e. the same as 1, above (this was just to test that there's no difference between using the headphones out and the master out of the VS2480).
The following results are all stated both "gross" i.e. the latency of the whole chain, and "adjusted" i.e. the latency of just the component under test, after deducting the VS2480's "inherent" latency.
3. Out of VS2480 master output, into Apogee Duet connected to MacBook pro and with Logic booted up @44.1kHz sample rate and 64 samples I/O buffer. Then straight back out of the Apogee's headphone out i.e. not using software monitoring. The idea here is to test how good Apogee's "direct monitoring" is. Result: 3mS delay. Adjusting for the VS2480's 1.67mS inherent delay, this means Apogee - even in direct monitoring mode - is adding another ~1.3mS of latency.
4. Out of VS2480 master output, into 1998 POD on "POD Clean" patch. Result: 3.3mS delay (~1.6mS adjusted).
5. As for 4. but using a different POD patch: this time the "Brit Hi Gain" patch. Result: identical to 5. above, so it seems POD patch has little effect on latency.
6. Out of VS2480 master output, into Kemper with Stomps, Stack and FX all disabled. Result: 4.3mS latency (~2.6mS adjusted).
7. Out of VS2480 master output, into Kemper on "AC30 Clean SM57" patch (I think the 3rd patch that comes up on the factory default list). Result: 5mS latency (~3.3mS adjusted).
8. As for 7. above, but using AS Mars MP Gain 8 patch. Results: identical to 7. above.
So what?
Well, first, this means that in a "real world" recording scanario (recording using Kemper into an Apogee Duet using Apogee's "direct monitoring") total latency is ~3.3mS for Kemper (the manual I think says 3.5mS) plus a further ~1.3mS of latency for the Apogee Duet's "direct monitoring" i.e. a total of 4.9mS.
Latency seems to be a bit like having a drink. You don't notice the first one, or even the second. But after a few drinks you definitely notice the cumulative effect.
4.9mS is right on the cusp of when no less an authority than Yamaha say "playing starts to become difficult" due to latency (i.e. hearing what you're playing fractionally late verses your actual playing). Here's a link to that Yamaha article:
http://www.yamahaproaudio.com/global/en/trai…solute_latency/
and, in summary, this is what it says.
signal path latency for in-ear monitor systems
1.15 - 2 ms Playable without any big problem.
2 - 5 ms Playable, however tone colour is changed.
5 - 10 ms Playing starts to become difficult. Latency is noticeable.
>10 ms Impossible to play, the delay is too obvious.
So, in summary, with a real world recording chain, the latency of playing using Kemper is such that "playing becomes difficult". This is my experience.
Back to my original question: is there any way of improving Kemper latency? I ask because my 20 year old POD has about HALF the latency of Kemper (~1.6mS vs ~3.3mS). And POD plus Apogee Duet comes in at ~2.9mS which is less than listening to Kemper with headphones plugged directly into Kemper.
To those that say "but 5mS of latency is like standing 5 feet away from a real amp / cab" I say: take a simple midi drum loop and shift e.g. the Kick backwards (or forwards) 5mS and then then try playing along to it. Or leave the Kick and instead move the Snare by 5mS. Or leave the entire loop as is, but add a click track mis-aligned by 5mS and try playing along listening to both. Then repeat the whole thing using 10mS instead of 5mS to see what Yamaha mean.
To me, Kemper drags. It just does. And I think latency is part of, but not, the problem. But it would be nice at least to try to improve the latency bit.
Thx!