Author |
Message |
creatorlars
Joined: Nov 26, 2007 Posts: 524 Location: Denton, TX
Audio files: 4
|
Posted: Fri Feb 01, 2008 12:54 pm Post subject:
XR2206 LFO? |
|
|
I picked up a couple of XR2206's from my local shop the other day, since they had them in stock. I was originally thinking I may build a couple of TH's XR2206 VCO at some point, but I don't really need additional VCOs right now... however, the datasheet mentions they can be used for LFO's... and I could definitely use a couple of very simple LFOs... is there an XR2206 LFO project around anywhere? |
|
Back to top
|
|
|
crashlander42
Joined: Oct 21, 2006 Posts: 292 Location: Orlando, FL (US)
|
|
Back to top
|
|
|
Thomas Henry
Joined: Mar 25, 2007 Posts: 298 Location: Southern Minnesota
Audio files: 2
|
Posted: Fri Feb 01, 2008 6:15 pm Post subject:
|
|
|
I believe the XR would make a fine LFO.
My somewhat exotic sync idea (used in the XR-VCO) would be particularly useful, I think. This would permit synchronizing the LFO to a rhythmic pattern.
But tread carefully before thinking of using the four quadrant multiplier as an amplitude control. It sucks as a VCA. In the XR-VCO and the MPS it shines, though, since it's being used as a ring modulator to create new waveforms.
But before getting too carried away, be sure to see what my parenthetical buddy Tim Servo has coming with the SuperController Mark II (or whatever it's called---I'm too senile to remember now), using the 8038. That's the LFO that does everything but clean the lavatory.
Thomas Henry |
|
Back to top
|
|
|
v-un-v
Janitor
Joined: May 16, 2005 Posts: 8933 Location: Birmingham, England, UK
Audio files: 11
G2 patch files: 1
|
Posted: Sat Feb 02, 2008 9:23 am Post subject:
|
|
|
Thomas Henry wrote: | That's the LFO that does everything but clean the lavatory.
|
Oh that's a shame
I was hoping that there would be an ultrasonic mode, a mode that could be used both to levitate my fillings as well as clean the bog out! _________________ ACHTUNG!
ALLES TURISTEN UND NONTEKNISCHEN LOOKENPEEPERS!
DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKSEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN. |
|
Back to top
|
|
|
numbernone
Joined: Aug 16, 2006 Posts: 477 Location: new york city
|
Posted: Sat Feb 02, 2008 8:37 pm Post subject:
|
|
|
I built a few XR VCOs with the extra cap per Bugbrand addon. Seems to make a perfectly capable square and triangle, quite slow with a 5uf cap. I suppose you could add a bunch of waveshapers etc. for a decked out model. I have tryed a reset from the sync jack, thus far with out luck.
Man I really need some retriggering LFOs... |
|
Back to top
|
|
|
Tim Servo
Joined: Jul 16, 2006 Posts: 924 Location: Silicon Valley
Audio files: 11
|
Posted: Sat Feb 02, 2008 8:56 pm Post subject:
XR2206 LFO? |
|
|
v-un-v wrote: | Thomas Henry wrote: | That's the LFO that does everything but clean the lavatory.
|
Oh that's a shame
I was hoping that there would be an ultrasonic mode, a mode that could be used both to levitate my fillings as well as clean the bog out! |
Maybe a new cap would give the LFO a higher range, in which case "LFO" stands for "Lavatory/Filling Oscillator." Or not.
I would think that a larger cap would drop the XR VCO down into LFO territory. Maybe a 2.2 or 4.7uF would do the trick. As far as Thomas' megasupercontrollerII LFO (from AS21C), I have the PCBs and I'm currently populating and testing one. I did make a mistake that is going to require a couple of cut and jumps, but I think that's it. I'll know more in the next day or so. This LFO has sync, expo FM, and a couple of different delay options, and is built with 8038, 3080, 555, 1458, 4016 and TL074 chips. It's a busy board, but it has some very enticing capabilities. I think we're calling this one the "Cucamonga." Mo' details as they're available.
Tim ('Cuuuucamonga where the wind comes sweepin' cross the plains) Servo |
|
Back to top
|
|
|
Danno Gee Ray
Joined: Sep 25, 2005 Posts: 1351 Location: Telford, PA USA
|
Posted: Sat Feb 02, 2008 9:02 pm Post subject:
|
|
|
Thomas Henry wrote: |
But before getting too carried away, be sure to see what my parenthetical buddy Tim Servo has coming with the SuperController Mark II (or whatever it's called---I'm too senile to remember now), using the 8038. That's the LFO that does everything but clean the lavatory.
Thomas Henry |
Ok, now that I'm salivating like a pvlovian pooch...Where's the info on this LFO? |
|
Back to top
|
|
|
Tim Servo
Joined: Jul 16, 2006 Posts: 924 Location: Silicon Valley
Audio files: 11
|
Posted: Sat Feb 02, 2008 9:35 pm Post subject:
XR2206 LFO? |
|
|
ARF!
Well, let's see. This is the LFO from Thomas' AS21C book. It's a 3 page schematic, and probably the busiest board I've laid out so far. On the feature side, it has:
*Delay that can be started by a gate signal, a footswitch, or a separate delay trigger.
*Sync input.
*Expo CV inputs.
*Gate and Trigger outputs.
*Selectable Ramp polarity.
*Selectable Tri, Sine or Ramp wave at the main out.
*Frequency Indicating Bipolar Blinky Light! (FIBBL) (©, ™, ®, pat pend)
Definitely worth saving an 8038 and a 3080 for. As I've said, the schematics are in AS21C, but it's complicated enought that I can understand not wanting to try breadboarding or protoboarding it. The PCB will definitely make this one easier. Coming soon. Really (I hope to finish testing/troubleshooting tomorrow during the Souper Bowl).
Tim (watching the Souper Bowl for the commercials) Servo |
|
Back to top
|
|
|
Danno Gee Ray
Joined: Sep 25, 2005 Posts: 1351 Location: Telford, PA USA
|
Posted: Sat Feb 02, 2008 9:38 pm Post subject:
|
|
|
Awesome! Sounds tasty. I now officially have one 8038 and a 3080 set aside for this wonder of boardage. I look forward to it's release.
Thanks Tim!
P.S. Love that book! |
|
Back to top
|
|
|
Thomas Henry
Joined: Mar 25, 2007 Posts: 298 Location: Southern Minnesota
Audio files: 2
|
Posted: Sat Feb 02, 2008 10:16 pm Post subject:
Re: XR2206 LFO? |
|
|
Tim Servo wrote: | As I've said, the schematics are in AS21C, but it's complicated enought that I can understand not wanting to try breadboarding or protoboarding it. The PCB will definitely make this one easier. |
Agreed. The breadboarding stage of this just about killed me. But it got even worse when I did the PNP Blue layout for the prototype; it was so complex, I had to do it on two separate boards and glue them together.
Yes, it's complex, but this is really the circuit that makes the rest of the synth sing. And Tim Servo, you neglected to mention the built in lag-time control which is what makes the delayed vibrato really something compared to its country cousin the SuperController. The steady, smooth increase to full modulation sounds so cool.
By the way, when I originally did the design a couple years ago, only my compatriot Scott Stites had the courage to beta test it on a breadboard. I don't know where he gets his patience; on my side it took an incredible amount of blaspheming to get the job done.
I don't want to discourage anyone, but really, this is a job for a PCB. Most of us don't have Scott's patience for breadboarding something that requires seven-hundred feet of hookup wire.
Thomas Henry |
|
Back to top
|
|
|
creatorlars
Joined: Nov 26, 2007 Posts: 524 Location: Denton, TX
Audio files: 4
|
Posted: Sat Feb 02, 2008 11:46 pm Post subject:
|
|
|
Wow, and I just wanted a couple simple LFOs!
I'll probably be ordering a board too. Thanks so much for the information and replies. |
|
Back to top
|
|
|
Coriolis
Joined: Apr 11, 2005 Posts: 616 Location: Stilling, Denmark
|
Posted: Tue Mar 11, 2008 11:56 am Post subject:
|
|
|
Hey, I was wondering when that LFO would show up, and now you're sneaking it in the back door!
Looking forward...
C |
|
Back to top
|
|
|
Tim Servo
Joined: Jul 16, 2006 Posts: 924 Location: Silicon Valley
Audio files: 11
|
Posted: Tue Mar 11, 2008 3:21 pm Post subject:
XR2206 LFO? |
|
|
Well, I try to avoid sneaking too much stuff in the back door...
However, Magic Smoke is working on the AS21C LFO and several other gizmos from Thomas' book. The LFO is a busy little beast, and I'm STILL in the troubleshooting & checking phase on the initial PCBs. I will scream and shout when they're checked out and ready to go. Next up will probably be the Multi-Mode VCF-VCA combo, or perhaps the VCOs. After that, probably the Clocked Noise / Sample-Hold / ADSR / along with a simple LFO in a combo module. In the words of Master Yoda, "Very preliminary, this news is."
Tim (also a busy little beast) Servo |
|
Back to top
|
|
|
Scott Stites
Janitor
Joined: Dec 23, 2005 Posts: 4127 Location: Mount Hope, KS USA
Audio files: 96
|
Posted: Tue Mar 18, 2008 8:20 pm Post subject:
|
|
|
Well, that's good news indeed! That AS21C LFO is a masterpiece, AFAIC.
Cheerios,
Scott _________________ My Site |
|
Back to top
|
|
|
|