by rcl on Mon Aug 20, 2007 10:47 am

subatomic wrote:when I had trouble with my 9090 snare r@f's page was a huge help.
(For example, here's his breakdown of the 909 bass drum)

he breaks down each 909 circuit and shows where the env/vco/vca/etc... are. makes it easy to understand each circuit.
especially useful for troubleshooting...

also, look for DC voltages that shouldn't be there, could mean you have a trigger stuck "on", or if you have the wrong type (npn vs pnp) transistor in, it might be shorting the trigger to ground making the trigger do nothing (or trigger immediately on power on then never letting go). it's intuitive to look for AC with a scope, then totally forget to look for improper DC offsets...


Thanks, those schematics did help quite a bit


I played with how I trigger a bit after trying to decipher the schematic and was surprised by what I found. If I keep trigger always at +5 and touch velocity/accent line momentarily to +5v and then short, I get a drum hit. It seems like 'trigger' gates the entire drum sound and 'velocity' actually initiates the whole sound/envelopes....

doing this stuff, the drum is close to what it should be.. and I think I've tracked down roughly where my existing mistakes are.



I'm still shocked by the "velocity vs trig" thing. I'd intended to just tie velocity down to a constant voltage and pulse a trigger. I originally intended to modify my 606 to send its trigger out and pull that in as trig in to the 909 kick, now it looks like I'll actually have to pull in both trig and vel/accent.

bizarre since i've never seen any drum machine modified to supply velocity out?? does anyone have insight on this?


Thanks,

Robert
rcl
 
Posts: 161
Joined: Wed Apr 19, 2006 6:30 pm
Location: Falls Church, VA

by crazy owen on Wed Apr 09, 2008 10:49 am

I know this thread is years old but I figured I'd chime in that you can still buy the 9090 kit from Trevor. I just received my boards/chips this week, Trevor said he had a pile of these so dont hesitate to contact him and buy a set if you want to build one too.

There are some great posts/info in this thread that I'm sure will be helpful, thanks to you guys for chatting it up in here, I appreciate it! Im really excited to get moving on the project, I dont know if anyone ever finished a MR9090 sequencer version but I may try to, if that doesnt work out I will build a dedicated MidiBOX for the 9090, I guess.

:)
crazy owen
 
Posts: 61
Joined: Thu Mar 06, 2008 1:03 pm
Location: Rochester NY

by rcl on Wed Apr 09, 2008 11:06 am

MR9090, that is exactly what I want. I hate the idea of rack mount with midi control, for so many reasons. That's what has turned me off on the TR9090 and what has made me interested in the mb-808 (DOES ANYONE HAVE ONE OF THESE THEY WILL SELL ME?)

What is the deal with the MR9090 though, does anyone know an enclosure this would work with or anything like that? it pretty much seals the deal and makes me interested in building one, but without an enclosure it's not very useful


Any tips on this from anybody? And any mb-808 for sale? :)
rcl
 
Posts: 161
Joined: Wed Apr 19, 2006 6:30 pm
Location: Falls Church, VA

by crazy owen on Thu Apr 10, 2008 2:21 pm

yeah the MR9090 makes the table top friendliness of the real 909 a reality for us DIY guys and that sequencer is right on the money. I have searched online to find pics of a finished MR9090 setup but not much luck yet, I should email the designer and see if he ever finished it or knows anyone who did. its easy to have an enclosure made, just $$$. but its not difficult to make an enclosure as long as youre okay with wood ends and a flat panel top, thats what I would make anyhow.

I hope by the time I get my 9090 ready to build that I can just go ahead and make it a MR9090 instead, thats a lot more fun for me to program with the actual drumbox in front of me... love that x0x pattern sequencing!
crazy owen
 
Posts: 61
Joined: Thu Mar 06, 2008 1:03 pm
Location: Rochester NY

by phono on Thu Apr 10, 2008 3:48 pm

in the meantime you could pick up an old korg er-1, it makes a great 16 step sequencer since all the pads output midi notes. I use mine to drive the 808 section of my drumstation :)
Image
x0x #733 Image SH-101 MC-202 TB-303 TR-606 TR-808 TR-909 MKS-50 Juno-106 A-100 Virus-B E-6400 SX-150 Monotron
User avatar
phono
 
Posts: 1502
Joined: Wed May 02, 2007 3:01 pm
Location: forum whore aka 2Cv

by crazy owen on Fri Apr 11, 2008 8:19 am

phono wrote:in the meantime you could pick up an old korg er-1, it makes a great 16 step sequencer since all the pads output midi notes. I use mine to drive the 808 section of my drumstation :)
thats a good idea too.

I got an email back from Marko / Mulletronic, what a nice dude - "I'm a junkie for all step sequenced hands on styled gear. I have 101, 606, 707 and 808 at home and a pair of custom built 303's (acidcode ml-303's)."

ready for some eye candy?!?!?!

here is a pic of his MR9090 prototype, SICK!
I would rather see some thinner knobs so my fat fingers can have some room to move but otherwise this is a sweet little drum machine, wow.

Image
crazy owen
 
Posts: 61
Joined: Thu Mar 06, 2008 1:03 pm
Location: Rochester NY

by phono on Fri Apr 11, 2008 8:23 am

crazy owen wrote:
phono wrote:in the meantime you could pick up an old korg er-1, it makes a great 16 step sequencer since all the pads output midi notes. I use mine to drive the 808 section of my drumstation :)
thats a good idea too.

I got an email back from Marko / Mulletronic, what a nice dude - "I'm a junkie for all step sequenced hands on styled gear. I have 101, 606, 707 and 808 at home and a pair of custom built 303's (acidcode ml-303's)."

ready for some eye candy?!?!?!

here is a pic of his MR9090 prototype, SICK!
I would rather see some thinner knobs so my fat fingers can have some room to move but otherwise this is a sweet little drum machine, wow.

Image



tbh i think thats ugly as hell, really poor design, gaudy comes to mind :shock:
Image
x0x #733 Image SH-101 MC-202 TB-303 TR-606 TR-808 TR-909 MKS-50 Juno-106 A-100 Virus-B E-6400 SX-150 Monotron
User avatar
phono
 
Posts: 1502
Joined: Wed May 02, 2007 3:01 pm
Location: forum whore aka 2Cv

by crazy owen on Fri Apr 11, 2008 8:37 am

phono wrote:tbh i think thats ugly as hell, really poor design, gaudy comes to mind :shock:
well I also dont care much for the yellow front, black sides and chrome knobs but all of those things can be changed by the builder, I'm just really excited to see it built and working, thats what has me stoked.


I would make mine in the layout of a quasimidi raveoltuion, seems very easy to make and design that kind of enclosure and they look good in just black and silver.
Although I guess its hard not to want a box like most classic gear, similar to an original 909 layout/color/shape or in a box like this MidiBoxSEQ from Tom303 that has room for all of the control knobs and not so crammed into a little tiny space -

Image
Image




;)
crazy owen
 
Posts: 61
Joined: Thu Mar 06, 2008 1:03 pm
Location: Rochester NY

by Altitude on Fri Apr 11, 2008 9:23 am

I would look at the midibox drum seq. Moogah is on this list also
User avatar
Altitude
 
Posts: 975
Joined: Wed May 11, 2005 4:17 pm

by phono on Fri Apr 11, 2008 11:00 am

crazy owen wrote:
phono wrote:tbh i think thats ugly as hell, really poor design, gaudy comes to mind :shock:
well I also dont care much for the yellow front, black sides and chrome knobs but all of those things can be changed by the builder, I'm just really excited to see it built and working, thats what has me stoked.


I would make mine in the layout of a quasimidi raveoltuion, seems very easy to make and design that kind of enclosure and they look good in just black and silver.
Although I guess its hard not to want a box like most classic gear, similar to an original 909 layout/color/shape or in a box like this MidiBoxSEQ from Tom303 that has room for all of the control knobs and not so crammed into a little tiny space -

Image
Image




;)


now thats much more like it ;)
Image
x0x #733 Image SH-101 MC-202 TB-303 TR-606 TR-808 TR-909 MKS-50 Juno-106 A-100 Virus-B E-6400 SX-150 Monotron
User avatar
phono
 
Posts: 1502
Joined: Wed May 02, 2007 3:01 pm
Location: forum whore aka 2Cv

by crazy owen on Fri Apr 11, 2008 11:35 am

ha, yeah I figured maybe that Tom303's MidiboxSEQ would be more like what you were thinking... not even one inkling of being an eyesore for that machine, its gorgeous! wonderful box design for sure, its a shame he doesnt have a dedicated site with pic/banned of it because I love that layout.
crazy owen
 
Posts: 61
Joined: Thu Mar 06, 2008 1:03 pm
Location: Rochester NY

by AngryChef on Wed May 28, 2008 12:06 am

I am still working on the foundations of it, but I am working a really crazy project that combines two Analogic-ACS TM-116s and the 9090 boards. I haven't totally figured out what I am going to do for the clock (and the ensuing trigger/velocity issues that were in discussion here), but I do plan on cramming a MFX processor into the enclosure. Wish my dumbass luck.

I am still working on the front panel layout (which, I admit may seem odd) to save trouble as the thing starts to come together mechanically. Yay for banana jacks!

I have almost all the passive components together thanks to the fine folks at TAW Electronics. Nearly all the components are WIMA (polypropylene caps) and Panasonic (electrolytics).

I intend to do as pro a job as possible so this is probably going to take quite a while and may get pushed back in the interest of finishing my second bcbox'ed x0xb0x. We shall see.
Angry "n00b" Chef
User avatar
AngryChef
 
Posts: 77
Joined: Wed Jan 17, 2007 2:11 pm
Location: Southern California

by Altitude on Thu May 29, 2008 6:28 am

AngryChef wrote:I am still working on the foundations of it, but I am working a really crazy project that combines two Analogic-ACS TM-116s and the 9090 boards. I haven't totally figured out what I am going to do for the clock (and the ensuing trigger/velocity issues that were in discussion here), but I do plan on cramming a MFX processor into the enclosure. Wish my dumbass luck.

I am still working on the front panel layout (which, I admit may seem odd) to save trouble as the thing starts to come together mechanically. Yay for banana jacks!

I have almost all the passive components together thanks to the fine folks at TAW Electronics. Nearly all the components are WIMA (polypropylene caps) and Panasonic (electrolytics).

I intend to do as pro a job as possible so this is probably going to take quite a while and may get pushed back in the interest of finishing my second bcbox'ed x0xb0x. We shall see.


Are looking to use wima caps for the 9090? They are spaced wrong and will be a pain in the ass to work with (trust me, made the same mistake). IIRC, the 9090 boards are spaced for 7mm, not 5.
User avatar
Altitude
 
Posts: 975
Joined: Wed May 11, 2005 4:17 pm

by AngryChef on Thu May 29, 2008 11:50 pm

Thanks for the tip!

I think I am covered because the place I got them from had all the values in 7.5mm pitch (unlike larger distributors like Mouser and Digikey) ... Except for those weird little 33pF ones those are 5mm (I'll have to bend them just a little).

What did you use for your 9090? Are you finished?
Angry "n00b" Chef
User avatar
AngryChef
 
Posts: 77
Joined: Wed Jan 17, 2007 2:11 pm
Location: Southern California

by subatomic on Fri May 30, 2008 1:41 am

i had to benda bunch of mine, not a big deal, but it'll slow you down a bit. the 9090 still works with the smaller ones though. so all you lose is perhaps patience ;)
User avatar
subatomic
 
Posts: 508
Joined: Wed May 11, 2005 2:12 pm
Location: Chicago