KVR Audio

Hink · Post by **Hink** » Wed Jan 04, 2012 6:41 pm

Sascha Franck wrote:I can't supply any answers to this thread, but if you are getting along, PLEASE keep us posted in this thread, if possible with detailed instructions.
Personally, I don't know shit about programming and what not, but for a number of years by now, I keep wishing for a "totally integrated guitar system" (or whatever). All of the available systems fall completely short on that.

Just one thing I may add: Several years ago (uhm, must be like almost 20 or so already) I borrowed a guitar from a colleague (he's more of an electronic dude rather than a guitar player) and what he did was routing the signal of each PU out of the guitar through some sort of multicore into a switching/controlling unit that ended up in his pedalboard. PUs were then switched via some (rather early I think - don't remember the model) MIDI switcher and the volume was controlled via a foot pedal.
Apart from PU switching (which I personally prefer to do manually, at least as far as the current state of technology goes) you couldn't do much unusual things with that setup, but it was already quite interesting that I could switch the PUs along with the presets of the GP8 I was probably using (hm, might have been something else... it's really a long time ago).

Cheers
Sascha

very easy to do Sascha, I have done this with one guitar now and my baritone, besides the cost of an ABY pedal it will cost you under ten dollars. On mine I can switch from normal operation to stereo operation with an onboard switch. Stereo sends each pup to it's own output (and fwiw I have pres on both pups in both guitars, in mono only one pre gets used).

In stereo mode I can either record both signals on separate tracks and use my DAW's automation to switch between or blend pups after recording (none of this cancelling stuff like on some guitars). If I use a pedal say for live a simple ABY works great or skip the ABY and just use two amps. Parts needed are a second jack and one spdt toggle switch. When you record two different tracks the possibilities are amazing, an ABY pedal is not needed for just recording but I can use my ABY on one pup add a second and you can record dry tracks as well (I use my Boss CH-1 as a second splitter because it has a dry out for stereo...I just don't use the chorus so I have two of the same signal)

BTW welcome to the DIY forum

obiwanjacobi · Post by **obiwanjacobi** » Fri Jan 06, 2012 9:24 am

I received my order for the analog switches and made a test circuit to see how it would work if I'd switch my guitar output with them.

The output of my guitar runs through the analog switch (74HC4066) and back to the amp. The button on the bread-board opened the switch and no sound was heard.

I could not hear any difference in sound between running the signal through the analog switch and just connecting the input to the output on the board.

So far so good. Still waiting for my Arduino to be delivered...

obiwanjacobi · Post by **obiwanjacobi** » Sun Jan 08, 2012 6:37 pm

I got the Arduino Uno board talking to my digital potentio meters, yeah!

Next step is to put it all together.

What kind of serial/parallel and in-phase/out-of-phase options would you like for the guitar pickups?

Hink · Post by **Hink** » Sun Jan 08, 2012 6:43 pm

I prefer parallel/split/series using an on/on/on toggle...thanks for keeping us updated

jonnyG · Post by **jonnyG** » Sun Jan 08, 2012 6:53 pm

Much win in this thread, there is! Thanks for posting it up, obiwan.

Yeah, I like series / parallel switching for my humbuckers. But I'm a gain monkey and don't like hum, so ymmv.

Am very interested in your use of Arduino too. As someone who's looking to take the plunge in that regard it's great to see a real world application that I can relate to.

obiwanjacobi · Post by **obiwanjacobi** » Fri Jan 20, 2012 8:57 pm

Made some progress. I hooked up one pickup to the circuit. I fear I have to put in a pre-amp because too much of the signal is eaten away by the analog switch and the digital potentio meter (volume).

Also I pickup "a lot" of noise from the Arduino so also looking to filter and shield that.

Any suggestions are welcome.

If you guys want/need more detail, just ask.

Hink · Post by **Hink** » Fri Jan 20, 2012 11:16 pm

did you try it with a single coil or a humbucker? For a pre I would go to general guitar gadgets and get the stratoblaster kit without the box and put that in the guitar. Easy to build, it has it's own pot as opposed to trimpots and very cheap.

Noise is going to be a tough one to get around I fear, perhaps put the midi electronics in a separate cavity that is shielded? I shield all my guitars anyhow with copper shielding tape but you say "a lot" of noise and that might become a major stumbling block.

thanx for the update

obiwanjacobi · Post by **obiwanjacobi** » Sat Jan 21, 2012 3:57 pm

I had the same kind of noise in one of my experiments - but even worse. Then I rewrote the code not to output settings to the digi-pot (using SPI) at each cycle but only when the value really changed and it reduced it dramatically.

I used a single coil pickup. I just now think of a test that I forgot to perform: test if the noise is still there if I let the Arduino on and just connect the pickup to the output (input of my amp). I will try that.

Taking all electronics out of the guitar has been suggested but at this point I just want to get some experience with the electronics so I can make 'better' choices. But even when I remove the electronics from the guitar, I think I have to deal with the interference anyway.

I have also been thinking of shielding but also of de-coupling. For instance: perhaps I could decouple the way the audio signal is going through the digi-pot. Not sure yet how, though...

Thanx for the suggestion of the pre-amp.

Hink · Post by **Hink** » Sat Jan 21, 2012 5:24 pm

a single coil is more than inviting noise, it's the nature of the beast and it's going to pick any noise and rfi it can

obiwanjacobi · Post by **obiwanjacobi** » Mon Jan 23, 2012 8:42 am

Hink wrote:a single coil is more than inviting noise, it's the nature of the beast and it's going to pick any noise and rfi it can

I know. I just dont have any humbucker laying around

I will test how the noise is, when I remove the single coil, that will give an estimate on what it contributes.

Thanx.

obiwanjacobi · Post by **obiwanjacobi** » Thu Jan 26, 2012 6:29 pm

Hmm, this only misses a midi in...

Hink · Post by **Hink** » Thu Jan 26, 2012 6:40 pm

did he say available mid 2011?...I think he did because the video is from NAMM 2011

obiwanjacobi · Post by **obiwanjacobi** » Fri Jan 27, 2012 10:41 am

Yepp, you can buy them.

Seems like they've also covered the Midi in functionality.

Damn, they stole my idea!

I would really love to know how they did the electronics. I bet its just an audio switching matrix IC. Al they have to do is expand the unit to also produce stereo sounds and perhaps some extra pickups (like 3 humbukers)

Hink · Post by **Hink** » Fri Jan 27, 2012 6:47 pm

I never heard of them until now...thanks

Sascha Franck · Post by **Sascha Franck** » Sat Jan 28, 2012 2:41 pm

Fwiw, I think that this "Game Changer" idea is quite nice. Two things that'd possibly get in the way for me personally:
- No proper hum supression in any of the single coil modes (maybe they should add something like Suhrs "Backplate Silencing System"...). You can even hear it in one of the Steve Morse videos that there's *quite* some hum going on.
- I still don't like the idea of a battery in my guitar. I'd certainly get away with that if there were revolutionary sounds to achieve, but well, while the entire thing is a great idea, I'm not sure whether it justifies having to care about batteries all the time.

And fwiw #2: I have already thought about some entirely passive switching system which would give me almost as much flexibility.

- Sascha

Crazy idea. Need help. Guitar with Midi In