The modeller with two brains: DL-4 eprom works in AM-4

Started by Processaurus, December 05, 2006, 02:59:43 AM

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Processaurus

Took the eprom out of my FUBAR'd DL-4 and stuck it in the AM-4 I got for lord knows what reason, and what do you know, it works.  Looper and everything.  Originally I thought I would need to poach the surface mount DRAM chip off the dead DL-4 (because the FM-4 and MM-4 don't have it, and its apparently neccessary for the delay), but for some reason the AM-4 has one soldered in already. 

Only drawback is that its mono now. I'll keep it in the red box to throw off gear heads.




Bernardduur

Am learning something new every day here

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Johan

 so now the next step in your modeler-evolution is to piggyback the two eeproms, with the exeption of the chip-enable-pin, put a switch to the chip-enable-pins and make it switchable....
..I did this with a friends POD..so now he has a POD/BOD   ;D
johan
DON'T PANIC

Processaurus

 
Quote from: Processaurus on December 05, 2006, 02:59:43 AMOnly drawback is that its mono now.

Heh, jumped the gun on this, theres a bug, it turns out it has a big volume boost when its on.  It also has the volume boost if you use the fake bypass where the DSP is always on.  I'll have to peak at the analog opamp input and output sections to see where this is coming from, the brute force approach would be to put a volume pot on the output before the relay, if there isn't any clipping anywhere on the input.  Shouldn't be too hard, though it does make this less of a quick fix for those who's greenie has died.

Quote from: Johan on December 05, 2006, 07:56:22 AM
so now the next step in your modeler-evolution is to piggyback the two eeproms, with the exeption of the chip-enable-pin, put a switch to the chip-enable-pins and make it switchable....
..I did this with a friends POD..so now he has a POD/BOD   ;D
johan

Awsome! :icon_biggrin:  Not knowing much about DSP stuff I looked up the Atmel chip's datasheet with that exact mod in mind, I thought one would have to use some cmos analog switches and switch the 8 outputs.  Thats great news that you can do it just with the chip enable pin.  So was it alright with both eproms outputs connected together in parallel?  Could you change which eprom you were using without having to reset it?  I wonder if the user presets are stored on the eprom?  I'm real curious about this, and am not squeamish about hacking the AM-4. 


Mark Hammer

This was actually something someone here stumbled onto a couple of years ago.  The various "modeller" series floor pedals provided essentially the same consistent platform, and EPROMs from one could be placed into another and "turn it into" the pedal the EPROM came from.  Of course, this necessitated the user to get into the bowels of the pedal and extract/reinstall the EPROM without damaging it.  It also took place within a context where the boxes themselves were legended in unique ways.

When the Tone Core series was conceived and launched, this sort of "brain surgery" was totally rethought, and made easier from the user's standpoint, and cheaper from the manufacturer's standpoint.  The Tone Core series uses a common platform and "dock", with reassignable plastic modules, containing the EPROM, pots and any switches, plus a small metal plate with whatever legending accompanies that module.  Instead of having to completely open up the chassis and fiddle with chips, the user can now press a little magic black button on the rear skirtof the pedal, and the module pops out.

When myself and a few others here were first beta-testing these pedals in the summer of 2004, the "magic button" was obvious to us, but Line 6 was being fairly tight-lipped about its plans.  It now seems that what we thought would happen did happen, and consumers can now purchase the plastic modules individually, without having to buy a separate dock for each. 

Of course, the usefulness of this concept really only comes into play when there are more modues available than you'd want to play with at any given point in time.  If I knew I wasn't going to use a ring modulator every day of the week, but someone made a multi-featured ring modulator module available for $50, I'd likely pick one up.  To date, Line 6 has only provided 11 modules with fairly common use effects.  Shortly before Jeorge Tripps left Line 6 (he served as project manager for the Tone Core series), he put out a call here to those with interest in designing third party modules for the Tone Core series.  There was interest among some members (obviously only a few because few of us here, myself included, have sufficient DSP programming skills to participate in such a venture), but I don't know where it ended up.  It may well still be going on behind the scenes, or may have run out of wind once Jeorge left.  It is often the case in organizations that if you have a great idea mere nanoseconds before someone else in the organization comes up with the same idea, or agrees to support you, it becomes YOUR initiative, and if you aren't available to lead it any longer, for whatever reason, it dies quickly.

In any event, the idea of transportable "identities" is something made possible by DSP-based effects and is one of the more truly exciting developments in FX in recent years.  Some companies, like DOD/Digitech, have ventured out into the world of digital pedals, but as yet the pedals are conceptualized as unique items.  It may well be that there is a common platform underlying the Crossroads, Experience and Rey May pedals, but the boxes are legended uniquely, without any evident access to re-locatable identity modules.  So, for the time being, Line 6 is leading the way in this regard.  I hope it works out for them.  It's a bold, but smart move.

Mr.Huge

Basically there are 3 PCBA's build for the modeler series.
DL4 (stereo with DRAM installed)
MM4 & FM4 (stereo PCBA no DRAM)
AM4 & DM4 (mono PCBA)

The AM and DM have the DRAM to reduce program switching time. Basically, all 4 presets are stored in the DRAM for immediate recall. However, the Mono and Stereo PCB's differ... The Mono, being used for distortion has some analog pre and de emphasis to reduce noise. Also, we wanted to be able to slam the front of a tube amp like an analog drive box can. Hence... More gain in the mono PCBA's.
-Mr. Huge

Hi Mark!
BEN:   Mos Eisley Spaceport. You will never find a more wretched hive of scum and villainy. We must be cautious.

LUKE:   But I was going into Toshi Station to pick up some power converters...

VADER:   I find your lack of faith disturbing.

Processaurus

Quote from: Mr.Huge on December 05, 2006, 07:46:17 PM
The Mono, being used for distortion has some analog pre and de emphasis to reduce noise. Also, we wanted to be able to slam the front of a tube amp like an analog drive box can. Hence… More gain in the mono PCBA’s.
-Mr. Huge

This forum is great, its so cool when someone with inside info will stop by and have some enlightening tid bit.  So I tried replacing the 47K pulldown resistor with a 50K trim pot as a master volume on the output, before the relay, but there was so much gain that there was clipping (though it was nice looking soft clipping) already present at one of the differential outputs of the Crystal DAC (from a moderate input signal of ~300mV), so I started looking at the input section, traced the signal through the first inverting opamp stage with a gain of 47, and got as far as looking at what was happening on the second half of that opamp (which looked like another inverting gain stage, and differed from the DL-4 PCBA I had out for comparing). 

Say, Mr. Huge, you don't have a schematic of the analog input section of those on hand, or know where the extra gain is added compared to the stereo PCBA, do you?  I'm also not sure if the pre/de emphasis makes a difference in tonality, though I wouldn't be too picky if it functioned sans distortion.   

Mark, yes it would be great if 3rd party (or even... boutique? Boutique digital??) designers were encouraged to make modules for the tone core boxes, line 6 seems stuck for the moment on emulation of vintage gear, when there's so much possible with the digital platform that people are trying with software plug-ins.  In particular I'd love to see a bitcrusher module, also a ring mod with a bunch of options would be neat.  It would be great if alesis could make modules for what would have been the second generation of the ill fated ModFX line, they were planning some neat stuff, like an extensive formant type filter, and a lo fi pedal that did vinyl and warbly tape sounds...  Also an envelope modifier would be outstanding, like the EH attack decay or the SPL transient designer, the list could go on and on like kids talking about how to make the ultimate video game...

sfr

Having never seen one first hand, I'd be interested in knowing how the Tone Core docks mount, and how easy they are to attach to external connections.  Some of those modules are very tempting, being able to do cool digital stuff I can't do DIY, and wouldn't mind having.  I'm in the process of building an all-in-one box with all my DIY pedals, and the ability to stick something like the Echo Park into that box rather than have another separate box tied down on my "extras" board with my wah and my volume pedal and stuff would certainly be the kicker that would prompt me to purchase that over another delay.   I would mind taking up more horizontal realestate with two footswitches to replace the functionality of the dual-use box, it's more about having one less physical object to lug around.

sent from my orbital space station.

Mark Hammer

On my almost-a-pedalboard (stillsome wiring and attaching to do), I have 3 stereo Tone Core docks in a row.  Happily, the stereo output and input jacks line up perfectly for use with those otherwise useless solid straight male-to-male adapters.  What's really nice is that I can attach that whole 20lb assembly (well, not 20lb, but damn close!) to the pedalboard and NEVER have to worry about whether it's the pedal order I "truly" wanted, because I can simply press the magic black button and swap the effect order.  This is ONLY to be done with the power OFF, of course, so either you undo the power plugs rom the back, or you unplug the wallwart/supply first.

Quote from: Processaurus on December 07, 2006, 02:45:54 AM
Mark, yes it would be great if 3rd party (or even... boutique? Boutique digital??) designers were encouraged to make modules for the tone core boxes, line 6 seems stuck for the moment on emulation of vintage gear, when there's so much possible with the digital platform that people are trying with software plug-ins.  In particular I'd love to see a bitcrusher module, also a ring mod with a bunch of options would be neat.  It would be great if alesis could make modules for what would have been the second generation of the ill fated ModFX line, they were planning some neat stuff, like an extensive formant type filter, and a lo fi pedal that did vinyl and warbly tape sounds...  Also an envelope modifier would be outstanding, like the EH attack decay or the SPL transient designer, the list could go on and on like kids talking about how to make the ultimate video game...
As adventurous as any company might wish to be, you HAVE to lead with products that can justify your initial R&D costs, or else you risk moving from "adventurous" to "bankrupt".  (Owners loved the TI-99 personal computer, but low sales just about killed Texas Instruments.)  If there is any barrier to the Tone Core docks becoming a sort of common platform for more and more 3rd party modules from boutique or "name" designers, or up-and-comers, it is apparently the absence of a development system for their platform, targetting developers.  Jeorge made this particular hurdle clear in his notes to potential developers last year.  Being out of the loop now, I'm not sure where this is at.  I know some of the folks here entered into early discussion with Line 6, but I don't know how that went or how far it went.  There ARE nondisclosure agreements to contend with, but within the limits imposed by those, I'm wondering if some of those people might offer some (understandably) guarded comment here.  For instance, are you still involved with it or have you withdrawn?  Has Line 6 gone in a different direction or is this particular series still likely to stay alive for some time?  No need to discuss specific modules or target dates, etc.  A simple "Yes, it's alive" will do nicely.

Again, one of the real advantages of this identity-module approach is that one can easily and cheaply manufacture effects that are perhaps too outlandish or complex by themselves to be marketable to millions.  The risk in ponying up the dough for producing an entire effect pedal, complete with machining, packaging, shipping the entire box, etc, etc is substantial.  The risk in reprogramming an existing EPROM on an existing board (note the resemblance between Tone Core module layouts) and simply silkscreening another 2" x 2" face plate for the plastic module is substantially lower, encouraging some creativity and risk-taking, or at least placing fewer disincentives in the way.

And that is what I love about this series.  Line 6 has made it possible to give themselves permission to take musical chances.

sfr

Quote from: Mark Hammer on December 07, 2006, 10:02:40 AM
On my almost-a-pedalboard (stillsome wiring and attaching to do), I have 3 stereo Tone Core docks in a row.  Happily, the stereo output and input jacks line up perfectly for use with those otherwise useless solid straight male-to-male adapters.  What's really nice is that I can attach that whole 20lb assembly (well, not 20lb, but damn close!) to the pedalboard and NEVER have to worry about whether it's the pedal order I "truly" wanted, because I can simply press the magic black button and swap the effect order.  This is ONLY to be done with the power OFF, of course, so either you undo the power plugs rom the back, or you unplug the wallwart/supply first.

You know, that's a handy option I hadn't thought of, and something to keep in mind if I end up considering more than one Tonedock module   My post above was wondering about the possibility of integrating a tonedock module into something like what Andre posted here.  The other thing that would be nice would be if Line 6 released a Tonecore dock with multiple "bays" (of course, this is probably something that would be more useful when/if more modules come out.  Or perhaps a Line 6 guitar with a dock for a module in it? 

Quote
And that is what I love about this series.  Line 6 has made it possible to give themselves permission to take musical chances.

That's the thing that excites me too, and I hope that we end up seeing the full potential of this realized.
sent from my orbital space station.

Peter Snowberg

Quote from: Mark Hammer on December 07, 2006, 10:02:40 AM
If there is any barrier to the Tone Core docks becoming a sort of common platform for more and more 3rd party modules from boutique or "name" designers, or up-and-comers, it is apparently the absence of a development system for their platform, targetting developers.  Jeorge made this particular hurdle clear in his notes to potential developers last year.  Being out of the loop now, I'm not sure where this is at.  I know some of the folks here entered into early discussion with Line 6, but I don't know how that went or how far it went.  There ARE nondisclosure agreements to contend with, but within the limits imposed by those, I'm wondering if some of those people might offer some (understandably) guarded comment here.  For instance, are you still involved with it or have you withdrawn?  Has Line 6 gone in a different direction or is this particular series still likely to stay alive for some time?  No need to discuss specific modules or target dates, etc.  A simple "Yes, it's alive" will do nicely.

Line 6 created an excellent design with the ToneCore series. The analog sections were very well thought out to allow for a wide range of algorithms to be implemented in very high quality. Even with a wonderful DSP used, your digital can only be as good as your analog sections allow it to be.

I'm under NDA with Line 6 and have everything they had to offer in terms of a development system for the ToneCores, which isn't too much. The tools are made for internal use and the Line6 code is unavailable to developers. They have blank modules available, but the documentation is limited and for something really neat, you need to write your own control code in addition to the effect code. You need to be able to code for two different processors and understand the hardware, which ups the requirements a bit.

Not being from Line 6, I cannot comment about the future of the series, but it really is a fantastic platform that has MANY years of life left in it from a developer's standpoint.

I designed a new module from scratch (not using the three existing Line6 module boards) which I feel has the potential to become a serious platform in itself. Unfortunately, I had to put the effort on hold in February due to a cash shortage. I predict that I'll need roughly $2,500 to result in a complete design with a few proof-of-concept prototypes (boards etched, chips & etc. mounted, plastic machined to fit the existing docks).

If anybody is seriously interested in investing in a new and highly capable ToneCore module, please PM me. ;)
Eschew paradigm obfuscation

puretube

bump

with request to move this thread to the DSP-forum

Processaurus

Fair 'nough.

This project got shelved because I unfortunately got my real DL4 to work with some eprom + DRAM switching voodoo, hence a shortage of fresh brains to go through with the transplant.  If I can procur more eproms or figure out what I need to program them, I'll trace out the opamp input section and convert it to the lower gain configuration that the stereo modelers use.  There are unused pads in that section on both the mono and stereo boards, which make me suspect you can make both circuits on it.

I asked Johan about piggybacking eproms, he said you'd piggyback them and just solder each pin to the one below it, except for the chip enable pin, which I would tie each one high with a resistor and use a toggle switch to ground one or the other.  I think it wipes out the patches when you do that unfortunately.

If I don't get that going I had the bent thought of sticking a Fab Metal PCB in there and permanently in series with the AM4 so one could use it as a 4 bank programable EQ/ Level control , but all heinous metal sounds :icon_twisted:.