Hexaphonic Pickup Project

[cycfi]

Hi,

Here's something you might find interesting:

Ubertar Hexaphonic Guitar Pickups - Home

Hello manifold,

Yes, I am aware of that. It's a passive design. I don't believe him about it being noiseless without some graphs. I have some graphs that show the Neo pickups are quieter than an EMG81 which is the quietest commercial pickup I have. Also, there's really no such thing as noiseless. Ours is at 72.91 dB (compared to Less Paul's 59.57 dB and the noisy strat at 47.52 dB). Also, being a passive high impedance design, it will have the characteristic coloration (I hear his samples peak at around 4-5KHz). It won't have the clarity of the Lo-Z pickup that no less than Les Paul himself advocates. Have you seen the page on "Sculpting the Tone"? An un-colored pickup is the perfect blank canvas for EQ matching and convolution.

[Kindly Killer]

Just wanted to say that your work looks great and I am interested to try it when you have a whole system ready to go.

FWIW may I suggest that you put a lot of thought into form factor of the outboard gear. Let me tell you what my rig is like and why. I play full time professionally, sometimes on big productions but mostly not - e.g. I played on this which just came out, but tonite I'm grindin out a 4-hour casual gig in a place that is literally named "The Juke House" LOL. I'm 42 years old and I'm done with multiple trips to the car. I have basically one small rig that I add to in order to do more with:

Guitar and a 1x12 combo with an AmpClamp. That's enough to do jazz and some casual gigs - and anything with very low pay LOL. BTW it might seem like more work to bring your own mic, but I've found that my interface time at sound checks is cut down to "next let's get guitar" - and I play four bars and I'm done - when i use the amp clamp and my own 57 [painted ugly for anti-theft]. Also I hear the exact same thing wherever I go - including precise mic placement

Pedalboard in the shape of guitar that can fit in its own flight case or in a double gig bag for self-transport. Has old school pedals, a Zoom G3, clean power, and a volume pedal for the effects loop. There is a "snake" to go with the pedalboard - it's just a group of homemade cables going back and forth with the amp with that braided wrap they use in computer builds. takes minutes off every single setup and teardown - just one cable to wrap and once you plug in the first plug, the rest just kinda fall close to where they go...

So with just that stuff I have a double gig bag heavily loaded with stuff, plus the amp. I can carry one in each hand and walk about a half mile before I get uncomfortable at all. I can sling the gig bag on my back and help someone else load in their overabundance of junk

Next I can add a notebook computer by just plugging a USB cable into my Zoom multi-effects, which can act as a usable audio interface. I use Ableton, NI Guitar Rig, MidiGuitar - just depending on what I'm doing at the moment.

Finally I can add a Roland MIDI foot controller that either controls Ableton with any kind of messages, or makes patch changes simultaneously in Guitar Rig and on the Zoom unit (you can really get creative with just those two little toy boxes). When I use the Roland foot controller I unplug the Zoom from the PSU (it's now bus powered from the computer) and use that plug to power the foot controller. The Roland is itself expandable - you can plug in a bunch of expression pedals for loads of CC's. E.g. I just got hired to MD a rap group for some summer shows, and I may end up doing the job of both bass and DJ. I did this as a sort proof of concept gearing up for that:

Oh yeah you can see my pedalboard in the background LOL.

I also bought stuff to build my own midi controller based on the Livid board, which is bus powered, but I am too lazy and the setup I'm using now has no real problems...

Point of all that is 1) it's a great, scalable system that has never really let me down. and 2) It's not really what I want to use. In a perfect would I would have a Fractal Axe-FX on a pedalboard, but they only come in a big, chunky rack unit. Everything else about it is perfect for what I do - there is lots of power, it's very malleable, easy to program, lots of choices for how to interface with it, but IT CAN ONLY LIVE IN A RACK. I actually have a case for a notebook and a rack, but that is such a PITA compared with what I have now - all the schlepping, the cables, fishing around the back of the rack - I'm done with it!

I thought really hard about - drew it on paper, even - building a sort of combo rig built around the Axe and a lightweight power amp. But that was going to be a long road when you factor in how much reading I was going to have to do to basically design my own monitor wedge type enclosure that would sound good, be portable, and work mechanically with covers, wheels, etc... I just don't have the chops and I'm not willing to learn what I would have to, and I don't see any big development deals in my future to throw money at that kind of custom work, so...

My advice to anyone developing something cool and tricky for guitar players: think about us workaday, blue collar guys out here on the ground. We have no tech and no crew on 99% of gigs, and there is no cartage for fly dates anymore. And when a young producer says he wants you to come to a "studio" - as often as not, it's just some dude in his house - with the same gear you have at home - maybe a few more mics and pres - so you might as well lobby for doing your tracks from home.

IMHO if you want to reach the masses, try to make something that can physically fit into a very portable rig in any way the user chooses. It's a lot easier to make a rack wing for a tiny box than it is figure out a way to shoehorn a giant 2u sized box into a tiny club rig.

It's just a wild guess, but I wouldn't be surprised if form factor alone killed a lot of great ideas for music gear.

Just thought I'd share my experience on the chance that it would be helpful.

HTH
Michael

[cycfi]

My advice to anyone developing something cool and tricky for guitar players: think about us workaday, blue collar guys out here on the ground. We have no tech and no crew on 99% of gigs, and there is no cartage for fly dates anymore. And when a young producer says he wants you to come to a "studio" - as often as not, it's just some dude in his house - with the same gear you have at home - maybe a few more mics and pres - so you might as well lobby for doing your tracks from home.

IMHO if you want to reach the masses, try to make something that can physically fit into a very portable rig in any way the user chooses. It's a lot easier to make a rack wing for a tiny box than it is figure out a way to shoehorn a giant 2u sized box into a tiny club rig.

It's just a wild guess, but I wouldn't be surprised if form factor alone killed a lot of great ideas for music gear.

Just thought I'd share my experience on the chance that it would be helpful.

Thank you, Michael. Wow. You have an amazing setup. Sounds wonderful too! It's amazing how much you can do with modern equipment. So, tell, me, what do you think would be a good setup/interface. Here's what I posted in another forum:

Multichannel audio interfaces are quite ubiquitous now that even your neighbour's daughter might have one with her laptop. I seem to be losing my focus with the bewildering plethora of options out there. Here are my current options from simple to complex:

1) A breakout box from the polyphonic pickups to individual outs. Add some MIDI control options so one can control some parameters from the guitar (e.g. pots and switches). The breakout box may also provide power for the active electronics. It connects to the guitar through a multi-wire cord similar to the Roland DIN connectors but more robust(!) and with more channels (perhaps up to 8). It connects to a multi-channel audio interface and to a computer or tablet or even a mixing board, if you want.

2) A multi-channel ADC in the guitar that sends USB2 (high speed) to a computer. The controls can also be sent through USB2 using MIDI so one can control some parameters from the guitar (again, pots and switches).

3) Stand alone processor. This also requires 2 above plus at least stereo DA converters. Perhaps some DSP co-processors can help the main processor.

4) Co-processor. This also requires 2 above. The processor acts as a preprocessor for the individual channels along with some basic effects (e.g. basic convolutions) for each channel. It then sends the pre-processed signals through USB-2 to a host computer.

5) Anything else? Suggestions?

[Kindly Killer]

Thanks for compliment. I agree contemporary gear is amazing.

regarding ideas for your project, i think my fantasy for an OS hardware kit would be as follows:
i buy a kit with professionally populated, compact PCBs. i still enjoy monkeying with through-hole components, cooking with dirt box circuits, but this is not that. i want a top-quality, tiny PCB assembled by a robot

i install the pickup (inside a HB cover, strat cover, p90 cover, etc) and a circuit that is easy to install and doesn't require any new holes. first i want to plug in a regular guitar cable and have the pickup function as a normal pickup - familiar response curve, plugs right into the front of a tube amp. that's first because without that, i can't use this guitar as my everyday guitar. no matter how portable/convenient is the outboard gear, IRL that gear is sometimes going to be at the bottom of a big stack at the front of a packed trailer, while my guitar is always

next i plug in to a very small box - possibly using a special 1/4" cable carrying the multiplexed signal. this box features a USB audio interface, 6 individual audio outs (2.5mm or something similarly small for installation, no need to address the sack-of-loose-pedals guys), a summed-and-filtered 1/4" output with a control to select different filters. also a standard 13-pin output to interface with that type gear. the usb audio interface shows the individual outputs, the summed output filtered, and the summed output flat

that would cover it for me personally with everything i can imagine doing right now. that would make it easy for me to get very creative

just some ideas

i hope there is something helpful in there
Michael

[cycfi]

Thanks for compliment. I agree contemporary gear is amazing.

regarding ideas for your project, i think my fantasy for an OS hardware kit would be as follows:
i buy a kit with professionally populated, compact PCBs. i still enjoy monkeying with through-hole components, cooking with dirt box circuits, but this is not that. i want a top-quality, tiny PCB assembled by a robot

i install the pickup (inside a HB cover, strat cover, p90 cover, etc) and a circuit that is easy to install and doesn't require any new holes. first i want to plug in a regular guitar cable and have the pickup function as a normal pickup - familiar response curve, plugs right into the front of a tube amp. that's first because without that, i can't use this guitar as my everyday guitar. no matter how portable/convenient is the outboard gear, IRL that gear is sometimes going to be at the bottom of a big stack at the front of a packed trailer, while my guitar is always

next i plug in to a very small box - possibly using a special 1/4" cable carrying the multiplexed signal. this box features a USB audio interface, 6 individual audio outs (2.5mm or something similarly small for installation, no need to address the sack-of-loose-pedals guys), a summed-and-filtered 1/4" output with a control to select different filters. also a standard 13-pin output to interface with that type gear. the usb audio interface shows the individual outputs, the summed output filtered, and the summed output flat

that would cover it for me personally with everything i can imagine doing right now. that would make it easy for me to get very creative

just some ideas

i hope there is something helpful in there
Michael

This is very close to what we are getting to. The mono output with the familiar response curve is a good idea. There's quite a bit of flexibility there, like e.g. using a state-variable filter to make the response adjustable. But I guess a fixed frequency response will also do. What about controls? I'm thinking of sending MIDI controls read from in-guitar pots and switches. Thoughts?

The 1/4" cable carrying the multiplexed signal like that used in the Dark Fire at first looked like a good idea. However, I got to talk to veterans behind the project and they are not happy. "First off, if you run the DF thru some processing, i.e., try to tie it into the rest of your rig, and it sounded too dirty. Noise upstream is amplified downstream". It is noisy! If I understand this correctly, that's the effect of multiplexing the analog signals. That may be OK for clean signals but the multiplexing glitches will be amplified l lot if you send it though distortion/overdrive. I'm going for a sturdy (not that flimsy 13 pin cable used by Roland) multi-pin cable.

The multi-channel USB interface will raise the cost significantly. It will be equivalent to having a complete audio interface in there, with drivers and all. I intend to do that, but maybe it would make more sense to have it as an option? After all, multi-channel computer interfaces are already quite common.

Finally, 2.5mm jacks are fragile. I do not know of any pro 2.5 jacks that can withstand the rigours of stage or studio use. Do you? I'm thinking more of using sturdy Neutrik 1/4" outputs (up to 8 in fact -- there's interest in the extended range guitar community).

Thanks for your notes and suggestions!

[Kindly Killer]

Hey Joel I understand what you are saying. I guess the form factor thing might not be realistic for an open-source project. The value is that it's OPEN! I guess my real fantasy something like a VG-99 that is open, more powerful, and is the size of a single stomp box LOL. Realistically, it's going to be a rack with the breakout box, something like an Octa-capture or Audiobox, and a notebook. That's cool.

MIDI controls: I did use the controls on the GK pickup in one band, and I was glad to have them. I guess it would be cool to have a few pins there on the board for when you need them. That beats the hell out of gluing a mini-keyboard to your guitar LOL

[cycfi]

Hey Joel I understand what you are saying. I guess the form factor thing might not be realistic for an open-source project. The value is that it's OPEN! I guess my real fantasy something like a VG-99 that is open, more powerful, and is the size of a single stomp box LOL. Realistically, it's going to be a rack with the breakout box, something like an Octa-capture or Audiobox, and a notebook. That's cool.

MIDI controls: I did use the controls on the GK pickup in one band, and I was glad to have them. I guess it would be cool to have a few pins there on the board for when you need them. That beats the hell out of gluing a mini-keyboard to your guitar LOL

We're getting closer to that goal, Kindly Killer. In the meantime, anyone interested in transparent covers? I think it's cool. Tell us what you think.

[Corvus]

Hello manifold,

Yes, I am aware of that. It's a passive design. I don't believe him about it being noiseless without some graphs. I have some graphs that show the Neo pickups are quieter than an EMG81 which is the quietest commercial pickup I have. Also, there's really no such thing as noiseless. Ours is at 72.91 dB (compared to Less Paul's 59.57 dB and the noisy strat at 47.52 dB). Also, being a passive high impedance design, it will have the characteristic coloration (I hear his samples peak at around 4-5KHz). It won't have the clarity of the Lo-Z pickup that no less than Les Paul himself advocates. Have you seen the page on "Sculpting the Tone"? An un-colored pickup is the perfect blank canvas for EQ matching and convolution.

I've tried the Ubertar pickups and can confirm that they're not noiseless though they weren't particularly noisy either. I liked their bright sound but the magnetic field was too narrow for bending in the neck position. That said he may well have changed his designs since 2009 which I tried out all the models he had available then.


Regarding multichannel cables I've had excellent experience using Planet Waves modular cable snakes with my current passive balanced 7-channel system. They're quite robust and stage-worthy and certainly widely available in North American music stores, if not worldwide.

[cycfi]

LEMO connectors

Regarding multichannel cables I've had excellent experience using Planet Waves modular cable snakes with my current passive balanced 7-channel system. They're quite robust and stage-worthy and certainly widely available in North American music stores, if not worldwide.

I’ve tried using snake cables. For the prototype, they work fine. However, I need at least 14 pins for 8 audio channels plus 1 mono, V+ power supply and MIDI. Unfortunately, the DB25 connector, commonly used for snake cabling, is designed to carry only 8 balanced audio signals (hot, cold and ground per channel).

Here's what I decided to use:



These connectors are made by LEMO (Switzerland). These are metal, self-latching multipole connectors with alignment key and gold plated contacts. These connectors are the best I can find.

Multi Pin Cables | Cycfi Research

[tedmich]

I’ve tried using snake cables. For the prototype, they work fine. However, I need at least 14 pins for 8 audio channels plus 1 mono, V+ power supply and MIDI. Unfortunately, the DB25 connector, commonly used for snake cabling, is designed to carry only 8 balanced audio signals (hot, cold and ground per channel).

Here's what I decided to use:



These connectors are made by LEMO (Switzerland). These are metal, self-latching multipole connectors with alignment key and gold plated contacts. These connectors are the best I can find.

Multi Pin Cables | Cycfi Research

wow those are super long, I'd contemplate recessing the jack to limit the non flexible length when they're plugged into the guitar, if you can still actuate the release mechanism.
14 pins eh? Maxi-con-X (Conxall) are way cheaper and available with 18pin/right angle but might be unsuitable.

Didn't the Moog guitar have hex pu's and a hex sustainer too? Alan Hoover (Maniac Music/Sustainiac) has spoken about making multi string sustainers but might need help with the SMD layout etc.

[cycfi]

wow those are super long, I'd contemplate recessing the jack to limit the non flexible length when they're plugged into the guitar, if you can still actuate the release mechanism.
14 pins eh? Maxi-con-X (Conxall) are way cheaper and available with 18pin/right angle but might be unsuitable.

It's a 19-pin cable. Pictures can be deceiving. It's just about the size of a 1/4" Neutrik guitar plug:



Like the neutrik plug, that grey thing at the end is just the rubber boot.

Do you know where I can find the 18pin Conxall you mentioned? I tried Digikey but could only get the connectors for RJ45, Ethernet.

[cycfi]

Didn't the Moog guitar have hex pu's and a hex sustainer too? Alan Hoover (Maniac Music/Sustainiac) has spoken about making multi string sustainers but might need help with the SMD layout etc.

An analog monophonic sustain system does not scale up to a polyphonic sustain system. We've got polyphonic sustain working in the lab, but it's rather unwieldy. IMO, the main issue is not the size (SMD layout), but rather how to balance and control all drivers. For this, I am going digital. I've given up on analog control.

[Corvus]

I’ve tried using snake cables. For the prototype, they work fine. However, I need at least 14 pins for 8 audio channels plus 1 mono, V+ power supply and MIDI. Unfortunately, the DB25 connector, commonly used for snake cabling, is designed to carry only 8 balanced audio signals (hot, cold and ground per channel).


These connectors are made by LEMO (Switzerland). These are metal, self-latching multipole connectors with alignment key and gold plated contacts. These connectors are the best I can find.

Multi Pin Cables | Cycfi Research

Those are beautiful looking connectors
Perfect for this application.



Your reply regarding the DB25 connectors is confusing to me as they have 25 conductors which are more than enough. I use one of these DB25 Terminal Blocks in my guitar and the Planet Waves connector modules eliminate the need for a breakout box on the other end.

Just mentioning what I use in case any readers find it suitable for their own requirements. I absolutely agree with you that the LEMO connectors look perfect for your needs.

[cycfi]

Your reply regarding the DB25 connectors is confusing to me as they have 25 conductors which are more than enough. I use one of these DB25 Terminal Blocks in my guitar and the Planet Waves connector modules eliminate the need for a breakout box on the other end.

How are the Planet Waves connector wired? Aren't they typically wired this way:


where each channel eats up 3 wires (hot, cold, ground)?

Perhaps I am missing something?

[Corvus]

Yes that's the way the end modules with 8 XLR or 8 TRS connectors are wired, but couldn't anyone could do their own wiring scheme if they're using a terminal block or breakout box at one end?

As I say I still love those LEMO connectors for anything needing 18 conductors. But this modular cable snake gets us up to 25 conductors for any situation that requires more.