
Search found 1062 matches
- Wed Apr 24, 2019 2:35 pm
- Forum: Announcements - Please read!
- Topic: Mike has passed away.
- Replies: 917
- Views: 115306
- Mon Aug 06, 2018 9:40 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
The board has provisions to set it up like a stock OBX card with the 2-pole LPF. I am trying to finalize the docs for this board as there are a number of revisions, but in this case you omit the DG508 and strap a jumper across the JP6 "OBX" pads near The (optional) notch trimmer T15. I'll have more ...
- Fri Jul 06, 2018 4:43 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
- Tue Jul 03, 2018 3:24 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
- Fri Apr 27, 2018 2:40 pm
- Forum: Music Tech DIY
- Topic: Old Crow Crowminius for Eurorack DIY build
- Replies: 28
- Views: 2685
Just make sure the fuses are set as noted in the source file. I use the avrdudess program which has settings for them, although you can also put them on the CLI/command line in a shell window. The .hex file should have these fuse settings and show up in the GUI when the file is loaded. Crow /**/ Cod...
- Sun Apr 22, 2018 12:50 am
- Forum: 5U Format Modules
- Topic: CS80 filter in 5u format
- Replies: 27
- Views: 3508
The MOTM-480 and RR-480 aka MOTM 480 mkII are the result of me spending a long time hand-selecting parts to test as a CS filter in place of the Yamaha parts in my CS-80. In the end, I got it as close as can be brought into this world. The thing to remember is, the filter is only one part of a much l...
- Wed Mar 28, 2018 9:17 am
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
- Tue Mar 27, 2018 3:44 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
I do provide pads for an axial tempco part on the newer rev boards as well. As I'm thinking of this it should be an easy solution to piggyback a 1k Akaneohm Tempco 3300ppm/°C on the LS318 like done on many other designs... Piggyback it from Pin 2 to Pin 7 of the LS318 et voilà... Then you could even...
- Tue Mar 27, 2018 3:38 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
Please note, the v2.3/v2.4 voice boards do not use LS318s, or DIP matched transistor parts at all. These use LM3046MX (SOIC14) or FMB3904 (SOT23-6). The older parts are just getting too rare, so I try to keep actively-produced devices as options. The LM3046 is on the last time buy list, which is why...
- Tue Mar 13, 2018 8:42 am
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
FYI: I've put up pre-orders for both a backplane with 4 voice boards set and a backplane with 8 voice boards set. These are of course bare board sets. The voice boards are my latest v2.4 type that use the AS3310 re-issued envelope generator ICs. The 2.4 boards are backward-compatible with the v2.0 e...
- Mon Mar 12, 2018 8:22 am
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
It is in fact a small OLED display. :sb: Given the OBX had presets and autotune, I plan to have the same thing here. The display is not strictly needed, but when I go to write and debug the patch manager program, it helps to have something I can use to show information. Hey Crow, is that a 4 pin SPI...
- Fri Mar 09, 2018 6:24 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
It is in the preliminary phase, but the control panel will look something like this: https://www.muffwiggler.com/forum/userpix2/6440_8vox_panel_v01_brd_1.jpg The 12mm buttons will all have integral LEDs. The section in the lower right area are individual voice panners which connect to the backplane ...
- Thu Mar 08, 2018 5:00 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
For those interested, I will be opening a pre-order page on my sales portal later this month for the 8-voice board sets. There will be full sets and as well as partial sets for those with existing voice cards. I am working on the front panel and control boards currently. Delivery of the backplane an...
- Thu Mar 08, 2018 3:47 pm
- Forum: Music Tech DIY
- Topic: crOwBX 8-voice
- Replies: 241
- Views: 25768
I did this spacing on purpose to avoid having to resort to creative capacitor lead-bending. 

jimfowler wrote:The 8 voice backplane does afford more space. The amount of space is uniform for all voice cards and is the same as the space between voices 2 and 3 on the 4 voice backplane. See attached photo.
- Sun Feb 25, 2018 12:41 am
- Forum: Music Tech DIY
- Topic: CS-80 YM26600/26700 IC Alternatives
- Replies: 14
- Views: 1330
- Sat Feb 24, 2018 3:10 am
- Forum: Music Tech DIY
- Topic: CEM3310 equivalent circuit
- Replies: 31
- Views: 11055
- Thu Jan 11, 2018 12:05 am
- Forum: Music Tech DIY
- Topic: More stuff from Crow's Atelier: crOwBX -> crOwBX-A
- Replies: 8
- Views: 719
Right, this card will have its own backplane, etc. It was not meant to work in a crowbx/OBX setup. I will deal with that when I test the board. Changing the resonance control profile is not very hard for either filter. :sb: Just checked the schematics. OBXa voicecard has some signals that are not TT...
- Wed Jan 10, 2018 9:41 am
- Forum: Music Tech DIY
- Topic: More stuff from Crow's Atelier: crOwBX -> crOwBX-A
- Replies: 8
- Views: 719
- Tue Jan 09, 2018 7:13 pm
- Forum: Music Tech DIY
- Topic: OBX voice card (with non-custom CEM3310 equivalent circuits)
- Replies: 1752
- Views: 209534
- Tue Jan 09, 2018 7:07 pm
- Forum: Music Tech DIY
- Topic: More stuff from Crow's Atelier: crOwBX -> crOwBX-A
- Replies: 8
- Views: 719
- Tue Jan 09, 2018 7:05 pm
- Forum: Music Tech DIY
- Topic: More stuff from Crow's Atelier: crOwBX -> crOwBX-A
- Replies: 8
- Views: 719
More stuff from Crow's Atelier: crOwBX -> crOwBX-A
Heya folks, With the return of certain chips courtesy of Alfa Rpar and Erica Synths, I can now make the crOwBX-A voice card. As with the crOwBX cards, these will be drop-in compatible for vintage machines but also able to be used with my 8-voice backplane. Right now it is a work in progress, but I s...
- Fri Oct 13, 2017 9:07 pm
- Forum: Music Tech DIY
- Topic: OBX voice card (with non-custom CEM3310 equivalent circuits)
- Replies: 1752
- Views: 209534
Re: some updates
The 4011 is either defective or the +5V going to it has an issue. VCO tuning issues are usually due to a bad timing cap or bad trimmer. --Crow Some updates about how my crowbx is behaving. VCO2 keeps going out of tune on two out of four voice cards. It takes several days/weeks for the tuning to go b...
- Fri Oct 13, 2017 8:43 pm
- Forum: Music Tech DIY
- Topic: OBX voice card (with non-custom CEM3310 equivalent circuits)
- Replies: 1752
- Views: 209534
Heya folks, a quick note. I am working on getting 8-voice stuff finished among my other projects. Since 3310 EGs are going to be made again I am going to try a 3310 edition of the crOwBX voice card. It will not replace my non-custom EG version, but it does simplify the build somewhat: https://www.mu...
- Fri Oct 13, 2017 1:12 pm
- Forum: Music Tech DIY
- Topic: Deckards Dream General Build Thread
- Replies: 1163
- Views: 93986
This diode is part of the negative rail voltage protection used on each 2164. If the 2164s are powered on the V+ pin with the V- rail missing/disconnected/unpowered a condition exists where a significant current flows into V+ which can damage the part. V+ internally tries to pull the free-floating V...
- Wed Oct 04, 2017 10:44 pm
- Forum: Music Tech DIY
- Topic: Deckards Dream General Build Thread
- Replies: 1163
- Views: 93986
Re: Deckards Dream General Build Thread
The essential item for any SMT soldering is a flux pen. It is ten times easier soldering using one vs. without one. I use the water soluable flux pen model, Kester 2331-ZX such as http://www.techni-tool.com/488CH450 Even for the 688 pieces of 0805-size 100nF ceramic bypass capacitor it will help. Be...