Posts by Per

BTW is there any global disable noise gate function? I think it seems to be per patch (as it keeps setting itself back up to 50%), but I generally never use a noise gate unless i want to do chugga chugga stuff.

Huzzah that was it. What a strange effect! Now all Christoph has to do is make a louder version and we'll have an inbuilt sitar pedal. Anyhow thank-you very much, it was driving my crazy.

Does anyone else notice a pretty nasty modulation effect when rolling back the pot on their guitar to the clean up point and playing through a crunchier amp on the KPA? It sounds like a cheap sitar pedal effect *booiiingggg*. Reducing the amp definition helps mask it a little bit, but it's still there.

It would be nice to be able to adjust how fast or slow the signal cleans up with pick-attack/guitar volume. Right now we can compress in the amp, but an attenuated guitar sound is often very muffled and my experience with the profiles I've tried so far is that I only get cleaning up in the last 5% of the throw on a normal guitar pot when the sound can't be rescued by any amount of compression.

When pressing "Store" on a Stack, Amplifier or Cabinet, please make it so that when it comes up with the page to name the preset it fills in the field with the name that's already in the Rig/Stack data (rather than what it does now which seems to be to take the name of the first stack preset in the presets list).

Busy busy busy! And profiling means effort man, like booting up into OSX, that involves like holding down the alt key for like almost ten whole seconds! Then fire up the Apogee and connect some less nicer mics then setup the routing and internal mixer, not to mention isolating the amp in the next room and running the cables through... do you have any idea how much mouse movement is involved in all that? Not to mention heavy lifting. Much easier to just turn on and play profiles that other people have made. That's what we've got Europeans for after all.

It's hard to know where the KPA fits in, studio or on the road, in some ways it seems it's more geared to on the road. The other possible thing is while you profile there's also going to be that added roundtrip latency going to/from the guitar/kpa/amp/kpa. So if it adds the delay caused by latency to the profile then it's adding the latency of it's own roundtrip in there on top of anything the amp itself has. And of course if you then go through a convertor/mixer that oculd add a bit more during profiling, and if the mic is placed further back... and all this is making the huge assumption that the KPA even takes this into account and adds a delay on purpose to match the feel, (which I kinda doubt).

As I said though, what I feel about playing the KPA and it's profiles and their responsiveness may or may not have anything to do with latency. In my situation I'm using it with studio monitors at between near to mid field distances (i.e. from sitting at a desk that they're mounted to, to standing up a few feet away), I'd have thought that even at 5ms the latency wasn't that much of a factor, though I know I really start to feel latency at 10ms in this setup (feels like slapback echo to me at that point), instead I'm assuming the play-feel i get is more related to the amp sim itself and it's characteristics.

Quote from Guitartone

You must have extremely high standards.

Not particularly. You just know when something clicks or doesn't is all.

I the Bassman (but could never own one because it would be too loud at the volumes I like). This is my favorite profile so far. Thanks. It's also great on the neck pickup with a little more verb for a Joey Santiago tone. Finally a tone that makes me feel enthusiastic about the KPA.

Hmm, I'm not sure if it's latency, it shouldn't be because allegedly it's only 2ms (not sure if that's just 2ms from guitar to in or all the way from in to out) which is nothing at all. But the unit feels quite flat and not always that touch responsive to me. There's a slightly detached feeling I get while playing.

Ta very much. I updated to the current firmware and when I try the browse dial it works, but I'd have guessed it was always meant to do that so maybe an intermittent bug, I'll keep an eye on it just in case.

Stacks, amps and cabs... Is it means to be possible to swap these out, or are they all just a part of a single rig that you must find and duplicate each time you want to make a new preset based on that amp? Whenever i go to browse with them the presets list just contains about 4 items and I can't find a way to add any more (I'd have assumed that the amps and cabs from any rig loaded would have been added to a central list here, but that doesn't appear to be the case).

Also is it normal that in Browser mode the Browse wheel doesn't do anything and you need to click through rigs with the rig buttons? (if so then that seems like something that you'd want to change).

Is the EXIT Led ever meant to be on fully bright, or is it normal to only ever half light up?

Is there any way to adjust the tonality of the sound as it cleans up? I know there's "Sens" for the volume, but no "Tone Sens" as far as I can see. I'm having difficulty profiling the actual distortion of my Mesa except at high gain, the cleaning up and touch characteristic veers sharply away from the way the amp itself is (is there a way to get it to do a more detailed profiling at lower volumes perhaps?).

Thanks

Quote from schneidas

LOL, in Greece we say "wanting the Pita (something like a cake I suppose) whole, and the dog not hungry".

The English is "having your cake and eating it", not a bad thing to wish for however I honestly didn't think it was too much to ask of an amp sim with two USB ports (obviously wasting space) on the back of it.

The process is as loud as you turn up your amp. All that needs to happen is that the KPA gets a good enough signal. So you can either use a passive mic like an SM57/58 and turn up your amp real loud. Or you could use a mic pre and then profile at a lower volume. I didn't find the profiling to be that much louder than playing guitar through the amp, so don't be too scared. Use the volume that you'd normally record at.

I think they need to start out by fixing the knobs so that they don't cause sudden massive jumps to start out with. But once that's done then I don't see much harm in "knob acceleration" provided it didn't happen too soon. An alternative might be to hold down the quick button and turn a knob to have it move much faster (or maybe some other button that's not in use at the same time as the knobs), or perhaps slower instead for fine tuning.

Quote from ckemper

Oversampling two signals prior to summing and downsampling it afterwards will give the same results as when you just sum the two plain signals.
In other words: the glue that you produce by oversampling will be summed, but later discarded by downsampling, without having an effect to the residual signal. You don't gain anything by that.

Where the hell have your found this theory?
You will not find any skilled DSP programmer stating that summing signals is sort of a challenge.
Please tell me the source where this kind of digital esoterik is teached.

Digital summing is:
Have sample streams of the same sample rate.
You add every corresponding sample.
Especially when you mix many streams (mixing desk), maintain a high bit width until the last stream is added.
Then the result can be truncated (cut the bits not needed).

CK

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Hi Christoph, thanks for chiming in. So I was wrong then with audio. Thanks for clearing that up. However I do think that this discussion is a diversion. As originally requested I'd still like 48k or other sample rates from the S/PDIF (or to allow the convertor to set the world clock/master rather than the Kemper), if nothing else I don't see it as in any way being a negative for the unit and it may even help bring in more sales (or at least not turn off anyone who may have been interested otherwise).

Quote from MadH

What I said is not the same as you mentioned on your post or at least not the way you wrote it. I am talking about using signals originally sampled at a higher rate, then summing and downsampling at the end. That normally produces better results but just because the source you are using is better/more accurate.

Maybe you were just confusing digital summing vs digital to
analog (mixer) summing. Some people prefer doing the summing in analog
even if all the source tracks are in digital because it sounds better for them.

No, that is what I wrote. i.e. Making the assumption (which as it turns out is wrong - see Christoph's post above yours) two approaches, high sample rate or reconstruction before modification of the sound at a higher rate (so effectively both = higher sample rate).

Anyhow based on the Nyquist rule (which is just a math rule, not specific to audio) then you'd need a sample rate of only above 2x the highest frequency that humans can hear in order to accurately reconstruct the waveform at the other end when accuracy = the same up to the limit of human hearing. So including what Christoph said above then unless higher frequencies/harmonics somehow were adding interference that's audible lower down (unlikely) then 44.1k should be just as "good" as 48k or 96k or even 192k, at least when it comes to human hearing, and the final result should null exactly if you were to take a mix made at 44.1k and one made at 192k and they were made to match frequency with the same aliasing filter as applied to the original sources for the 44.1k version (and according to what Christoph said that's regardless of whether they were reconstructed and re-aliased around the mixer/fx or if the samples went straight through the whole thing), and of course ignoring clock jitter. And I've heard that said before too elsewhere in these discussions.

I still prefer to work at 48k though, maybe it's purely psychosomatic, but it does feel easier to mix in and maintain clarity, or "better" as you say. Christoph has said in the past that there are parts of the KPA where the sampling rate is much higher, I wonder what they are and why they are there, also why audio software and interfaces offer higher samplerates at all, except maybe the cynic in me says as a meaningless checkbox to attract customers.

Yes that's what I meant (see my second post). And you may be right, but only Christoph can answer that. I'd be very surprised if the DSP couldn't handle it though given that even a Pod can do up to 96k and that's got a far less beefy DSP, also Christoph has said that internally it's working with much higher rates in certain places. But as mentioned, only Christoph knows if he can squeeze out that little bit more or not.

It would be sad if it's locked to 44.1 for it's lifetime, it would have been fun to use the Apogee convertors and keep an all digital signal path (not to mention less cables and therefore less hotswapping in order to use it), but being honest I don't hold much hope.

Yes it's vital. Fingers crossed that Kemper also thinks so.

No, you don't need it, but it sure would be nice to have. I've no idea how heave the DSP usage would be to do it and how much latency it would add, with the chip in the KPA and a nice algorithm it may be negligible, or it might be untenable, but there's no reason not to ask for it. The main idea though isn't so much to have convolution reverb itself as to be able to profile the room! And then the cool things you could do with that either during profiling of the amp or after as an effect.