To summarise: It will be a separate branch to the existing project with a different project lead (urklang) based on a newer, faster processor that sounds like it should initially retain compatibility with existing firmware due to being a drop in replacement. This thread has also discussed the possibility of producing an FPAA expansion board in the future with patcher integration to allow for programmable analog circuitry.
Next-gen and mini Axoloti hardware discussion
adnauseam
#474
Is there some sort of interest list? sign up page? For those who want to get in on the new boards?
I've sold my older Axoloti units in preparation for the new units - I'm excited to go past the axo control boards into my own DIY stuff this time. Can't wait!
@urklang ?
resynth
#475
What is the sampling frequency of the new boards?
The latency of Axoloti is quite high due to the 44.1khz AD/DA. For a given buffer size latency is halved by doubling sampling frequency. Of course higher frequency needs more processing power but that doesnt sound like a problem here!
resynth
#478
This is one of those funny questions, like oversampling, NOS components etc, where you do get people with the kinda "audiophile" attitude that claim they can hear certain limitations of gear. I'm well aware that 2.5ms is well within the ears integration time and equates to the time it takes sound to travel about a foot! However I still have reservations and, since you ask I'll give you the overlong explanation...
I'm a professional gigging violin/fiddle player playing mainly in band context. Professional bands need to be as "tight" as possible and it's really not black and white, sometimes we need all the help we can get. Sound is actually inconveniently slow. We've all observed how surprisingly close you can be to someone, say kicking a football, and see/hear the latency. Many people use this as an excuse that latency in gear is unimportant. I think the opposite as real world and digital latency are all adding up to a total latency.
As with most live musicians, I use more than just 1 effects box, I also like to stand a few meters away from the ear damagingly loud drummer/amps etc, digital desks are the norm now adding yet more latency. It is surprisingly easy to find yourself playing a bit too "lazy". I can hear this clearly in live recordings. Often when "comping" individual notes are moved manually to correct the timing, sometimes this is only a matter of a few ms.
I avoid using digital effects where analog is available but some things need to be digital, poly pitch shift, loopers, I wont let an audience hear my naked piezo PUP - it HAS to be through an FIR loaded with acoustic violin IR.
There are some stomp boxes that have unacceptable latency, EHX POG or Pitchfork being an example. Whatever anyone says I know I can hear the latency of a POG or Digitech Whammy. Having noticed the latency when using a POG into a looper (was finding it hard to get my loop point totally spot on) I measured it! 13ms. I find it very distracting and therefore don't use that sort of gear in performance. (shame as I really want HQ poly pitchshift)
Mostly, these days, stomp box manufacturers are taking this into consideration. My "cheapo Chinese" Nux NSS-5 IR loader claims a latency of 0.7ms (I checked this and actually measured 0.6ms but I'm probably not accurate). My Strymon gear also comes in at about 0.7ms, Source Audio are claiming 0.6ms on their new gear.
So, tightness of a band is not black and white and latency is relevant to tightness. Total latency is a combination of entire system as well as physical distances. Some of these factors can be compromised, others cannot but I feel an effort needs to be made in all areas where possible.
Axoloti is the slowest piece of gear in my current setup. Not only are the converters slow at 48khz some objects also take a little time (envelope follower, convolver or pitch follower for instance). Sometimes you need to route audio backwards or upwards leading to 16 samples each time. What if one Axo is not powerful enough and you have to use 2, the latency doubles!
I've accepted this with the Axoloti, it's not the end of the world. It seems impractical to change on a well developed system and it would take more of Axos limited processing power. However, if we're discussing a new and substantially more poweful system it would be amiss not to take latency into consideration.
patatos
#479
I partially see your point, being myself one of the rare flute players that uses a piezo in the headjoint ( like Florian Schneider of Kraftwerk did 50 years ago ). I play in an electric group with a huge volume on stage, I canāt hear my direct sound even in the quietest passages. My powerful class D amp is 4 or 5 meters from me ( 12 ms ), the farther the better. Sincerely this is the least of the problems. Iām aware that violin has no frets and to hear the sound without lag is fundamental.. but also with flute if I move the lip I can go out of tune of a quarter tone. I use an analog dist in front of a boss gt10 and Iām always struggling with feedback, I canāt leave my volume pedal aloneā¦ I can understand that summing in series 4 or 5 digital pedals latency goes up, (and this is one of the reasons I use an all in one pedalboard) but you must consider that pitch mangling algorithms have an inner latency not depending from the power of the DSP, it canāt predict the future. So returning to our Axo I think the latest teleplayer post says it all, and Axo would certainly benefit in doubling the sampling rate, the gain of more or less 1 ms of latency being the least obvious. Peace!
lokki
#480
let me write you from the same "boat" (professional gigging double bass player).
i really understand your struggles with added up latency, been there done that 
some general remarks:
latency perception is very much an individual thing.
musician a might be unable to play with an added latency of 8ms, where as musician b can play tightly with 13ms added. i play some orchestra gigs and there are players that can play the most rhythmic passages in sync while sitting apart 15 or 20 meters. (they have the help of the conductor of course)
i myself cannot bare more then 5ms total, but as i said others are very happy with that. (most common problem is studio headphone monitoring running thru DAW's)
a few suggestions that might help your setup:
for all fx that are not 100wet (i.e. reverb, delay) use an aux send approach rather then going thru the pedals with your dry signal. so you would set the wet level to 100% on those devices and send your fiddle signal via a mixers aux knobs. this way the latency does not matter usually on delay and reverb type fx. this is also how it is done on a mixing desk to avoid compromising the "clean" signal.
use in-ear monitoring, it will reduce latency quite heavily on "bigger" stages.
a bit more specific, if you want poly pitch shift, maybe look into adding a quadrophonic pickup (one that outputs each string separately) and feed it to a gk ready guitar fx. the new sy1000 has poly pitch-shift etc. on board and should be very low latency. i have successfully hacked a gk pickup for use on a double bass, feeding individual strings to further processors.
s8jfou
#481
Hi @urklang, and others . I have few questions to ask about all of that.
I started designing professional PCB. And by the way I was thinking this :
Johannes give us the shematics, if I made a pcb with these shematics, and if I recive my own board, what I need to do to make it work with Axoloti-patcher ? Do I need to copy the firmware from one of my original axo box ? if so how can I manage to do this ?
I'm thinking about designing my new synth with a builtin axoloti on the PCB. And I'm always waiting after new axo's always out of stock.
I don't really need it much powerful like the one you did Urklang, just the same than the original core, with few functions and components removed if I don't need them.
So that's my reflexion..
Thanks in advance
chrisj
#482
Funny that people are talking about high resolution audio and whether or not it's significantā¦ in the context of a synth
Thing is, I'm currently working with many Teensy-based 'Chord Organ' modules to do something the Axoloti could do as well or better, partly because it fits into a Eurorack system, and partly because in some ways we can get extremely high-quality audio out of even a Teensyā¦ for very specific waves.
Bit depth means NOTHING to a square wave, but sample rate means everything. On the Teensy, the degradation of the square wave is super obvious, and it's entirely due to naive wave generation from the very simple Teensy sound library. The sine is considerably better, the triangle pretty nice, the sawtooth pretty gritty again for the same reason.
Naive escalating of the sample rate will do a WORLD of good here, because we're doing primitive wave generation, a worst-case scenario for aliasing: and because in the case of a single squarewave we can output only one bit. We could be doing it on a digital output (buffering it, of course) and running at processor bus rates and have that be absolutely fine, because it's literally a square we're after.
Adding more voices to a square wave generator also takes not many bits: 16 is mad overkill, never mind 24, two or three or four bits would suffice to represent the result.
Considering the amount of interest in high-quality oscillators out there, and the ability to generate other waveforms in the analog domain given a correct square (without aliasing), I think there's a lot of potential hereā¦ especially with the talk of FPGA analog on the Zrna board. We have sophisticated osc objects in Axoloti-land that fix aliasing issues in other ways, but I'd just like to observe that the development of this hardware gives rise to completely different, distinct approaches to the problems that arise.
Just because people think we can generate squares at 48k 'perfectly' in a PCM digital system doesn't mean we can't also explore generating them naively at, say, 168Mhz 
SmashedTransistors
#485
Some news would be welcome an Axoloti based device would be easier to use than starting from zero on a Daisy or Teensy.
reubenfinger
#486
Hello Tiar, there has been some exciting updates & progress at the Zrna research discord chat, check over at https://discord.gg/xeztjzh
Ps. thanks for your continued awesome work, very excited about your new 4051 multiplexer object
urklang
#487
Hi everyone. It's been a while! The new hardware is finally ready to ship. You can read about all of the details here: https://zrna.org/akso
Appreciate your support!
Janko
#488
Fantastic! New features are very exciting. more powerful CPU, more ram, extra audio i/o, +/- 12v for Eurorack. $89 feels like a good price considering shipping is included, will defs pick one up when I can
ivofx
#490
I just ordered one. And I almost got to be the first to post in the forum
As I said I definitely want DIN midi.
I am wondering, can midi be transferred over the 3.5.mm jacks at all as an alternative to the missing DIN jacks?
(DIN connectors pins are available, but no breakout board as of yet. So I assume you can solder your own ones on)