Posts by tomoinn

So, as it appears there's no sign of an official Kemper foot controller I thought I'd look into making my own (I've a pretty solid hobbyist knowledge of electronics, microcontrollers and hardware design so it's not completely nuts!).

I've poked (virtually) the Kemper midi spec using some tools on my PC and I've got it responding to SYSEX messages and telling me things like the current rig name, effect slot names, types and status etc, so I can get the information I need. The main thing I want is for the board to provide feedback. I'm currently thinking of a fairly stripped down, seven pedal board with some display capabilities, MIDI in / out for the Kemper plus an additional MIDI out to control other gear on the pedal board when switching rigs in performance mode.

It would have:

Standard pedal switches for effects slots A,B,C,D,X,MOD,DELAY (I don't really care about turning reverb on and off from the pedal board), and a single mode switch. The idea would be to have the mode switch flip between effect control and performance / rig control. In performance control the first five switches would select rigs and the second two move up and down between performances.

Displays - RGB LEDs on each switch, plus possibly a number of 2x40 character LCDs. I could go for one per switch, but that's possibly overkill - one for each of the first five would do for me (these would actually correspond to the A,B,C,D,MOD slots, as I always have a stereo loop in the X slot). In effect mode the LEDs and display backlights would indicate the effect type by colour and the displays show a summary of the effect (probably its name), and in perform mode they'd show the names of the rigs in each of the (up to) five slots in the performance. I could in theory add another display to show current rig / performance name, but I'm not sure it's needed.

At this point it would be easy enough to add inputs for expression pedals, although I wouldn't use these for the kemper once they're managed by the microcontroller I could map them to whatever CC I feel like on either of the MIDI outputs. I guess a tap output would be useful (also for my other effects via the second MIDI out). I've not checked but I suspect that the Kemper honours MIDI clock for tempo in which case that's easy and I can manage the tap tempo in the pedal board rather than sending CC on / off.

I reckon the build cost for this would be around 200 pounds all in, buying from general hobby stores and not trying to be particularly economical. I'd use an ATMEGA328 as the central 'brain', should have enough capacity.

My main priority is to get something that fits on my pedal board and allows me to treat the kemper effects as if they're real stomp boxes, the other control stuff is a bonus. Feedback is critical though!

Thoughts? Any other hardware hackers out there?

Tom

So, a large box arrived yesterday from a certain German online music store 8o.

After a bit of fiddling around I ended up with a setup like this:[Blocked Image: https://dl.dropboxusercontent.com/u/70831580/Images/Kemper%20Routing.png]
I've not tried running the other instruments through it yet, for some reason I ended up playing my guitar for, um, about six hours. It's a lovely thing isn't it?

I'll upload some photos, and put a demo up on soundcloud when I've had a chance to tweak things properly for the 'cello, sax and bass.

Thanks for the help everyone!

Tom

Thanks both,

Sounds like it's a good option then, now to sell some old gear! Another benefit is that it'll actually be less stuff than the previous floor effects, guitar amp and bass combo. For the front end I'm planning to use an Eventide Mixing Link - they designed it originally to allow singers to use guitar effects, but it's ideal for this as it has a good mic preamp and outputs guitar level signals, It's got the connectivity as well such that I can leave one mic and one instrument level thing (so e.g. stick bass and sax, or guitar and cello) plugged in and use the footswitch to switch between them. I don't know whether I'd actually try to do that live, but given loop pedals exist it's an interesting option to have (stereo modulation effects and ditto X2 looper, also stereo, in the effects loop after the pre-amp part of the KPA should be ideal there).

I think I'll go for the non-powered KPA, I'd be tempted but the power amp in the power head is mono isn't it? Better for my purposes to get a powered FRFS speaker, with the option of a stereo pair. At least some of the time I'd be running direct into a mixing desk anyway so I'm not sure I'd ever really use the integrated power amp.

I'll report back when I get everything sorted out, might take a while but should be fun!

Tom

Hi there,

I currently play electric guitar, stick bass, cello and sax - the guitar through a regular amp, bass through a bass amp, cello and sax through mics into whatever PA exists. I've been trying to set up something that will allow me to use the same rig for all four instruments. I was initially thinking of putting a pedal board together with something like the TwoNotes C.A.B cabinet modeller, some kind of pedal based pre-amp for the guitar and bass and a mic pre-amp for the acoustic instruments, all feeding through my Eventide H9 for modulation and reverb along with a loop pedal. I'd then take the output of the board and either run direct into the PA or bypass the cab modeller and run into a regular amp. This would work, but the cost is getting high, which makes me wonder, can I do all this with the KPA?

I had a quick search for 'sax' and 'cello' here and there weren't any hits, so maybe it's a weird idea, but a FRFS system is what I need for all these instruments (the stick bass needs either that or dual bass / guitar amps and obviously the acoustic instruments normally run through one). I'd be using an Eventide Mixing Link as the input module as I can plug any of my instruments into that and get the appropriate instrument level signal out to drive an effects chain, then into the H9 (or maybe have that in an effects loop of the KPA assuming it has them), through the delay pedal and into the input of the KPA. A stereo 2x12 FRFS cab would be idea, but I've not investigated whether such things exist.

The power stage of the powered version of the KPA should be more than enough to handle amplification duties, so as long as the KPA itself can model something like a marshall acoustic amp (I see no reason it wouldn't) or even just act as a rather expensive cabinet simulator for when I don't need any kind of amp modelling, it should work, maybe?

I'd love to know whether anyone else is doing something like this - I know about the KPA from being a guitarist with an interest in all things tech, I guess running the other instruments through it as well wasn't something Kemper expected people to do, it's only popped back into my thoughts with the release of the bass models.

Would this work?

Tom