Review - Gakken analog synth kit

Sx150Box

MAKE Japan editor Hideo Tamura was kind enough to send us one of the new Gakken SX-150 Analog Synthesizer kits. Needless to say I was very pleased to receive it. The kit comes as part of the latest issue of Otona no Kagaku (Science for Adults) magazine/book(aka 'mook'). Though unable to actually read the issue, I fully enjoyed the included pictorials on synth history and hack/mod ideas for the SX-150 - a ton of good stuff in there.

Sx150Parts

Putting it together
Assembly of the kit requires little work - the circuit board comes fully assembled, just mount it to the panel and connect the stylus control strip. Power is provided by 4 AA batteries and a small speaker is included in the design. I highly suggest connecting the output to external amplification (this little guy really does sound quite good!). The "external source" jack accepts an amplified signal and converts its frequency into pitch control. Controls for LFO, pitch envelope, frequency cutoff, and attack/decay are included. Each potentiometer gives a wide range of response, so you have a relatively large amount of control over the sound.

Mod me
The simple design seems to suggest that the SX-150 wants/needsto be modded, hacked, and/or customized. Using the stylus/pitch-strip control only gives you a taste of the good sounds you can get from the kit. I decided to replace the strip with some momentary pushbuttons and a small trimpot for adjustment. You can see/hear the results below -

The SX-150 kit is very easy to use and some modding ideas are bound to come to mind should you get your hands on one. At the very least, you can choose from a number of included decorative decals - and at the more advanced end, schematic and code for using MIDI input has already been posted. I'm sure more sweet DIY add-ons are in the works - very awesome.

- Assembling the SX-150 on Flickr

- Otona no Kagaku SX-150 issue

- HOW TO - control an SX-150 via MIDI

- more Gakken kits in the Maker Shed



Related:

Recent Entries

Comments

Oldest comments listed first.

Posted by: Sebastien on August 26, 2008 at 6:22 PM

Video of live performance by Gakken

A few weeks ago there was a live presentation of this kit along with some performances. I decided to grab some videos. One of those videos is available below:

http://jp.youtube.com/watch?v=8ykFvbtBb1U


Posted by: shivam bhatt on September 18, 2008 at 10:19 AM

mod?

How did you add those buttons and trimpot? Is there a good guide for that sort of thing?


Posted by: Collin Cunningham on September 18, 2008 at 12:24 PM

@shivam - Regretfully, I didn't document the mod process - so I suppose no guide as of yet. Are you looking to add buttons in the same way or just a general orientation on the connections/wiring?


Posted by: shivam bhatt on October 18, 2008 at 11:24 PM

I'm just looking for a general orientation on how to do that. I've just now started discovering a love for DIY electronics, and i want to do cool things with this kit =)


Posted by: clay on November 24, 2008 at 5:21 PM

can you please put the schematic up for the switchboard or send them to me


Posted by: Anonymous on December 9, 2008 at 2:50 PM

I would love to have the details of how you did this. Seems really simple, but instructions or documentation would be needed for beginners like myself. Nice hack!


Posted by: Collin Cunningham on December 10, 2008 at 3:27 AM

I actually shot some video for a how to this week, likely be posted next.

For those who can't stand to wait - here's a boiled down description.

- replace the control strip with a chain of 7 4.7K resistors. connect one side of the chain to the white wire. connect the other side to the outside leg of a 100K potentiometer, then connect the 2 remaining legs of the pot to the blue wire.
- connect one leg of a switch at the junction of 2 resistors
- connect the other leg of that switch to the stylus' wire (aka ground)
- repeat @ every other junction where 2 resistors meet

I gleaned the basic idea from MFOS -
http://musicfromouterspace.com/analogsynth/keybrdcontroller.html

that's the gist of it, i'll post more detail soons!


Posted by: Derek on February 1, 2009 at 2:18 PM

external input does not work!

I think it's lame that the external input does not work. I was hoping with all the hype this got on Makezine site it would at least work as advertised. You shouldn't have to mod something that it is advertised to do....probably wouldn't buy Gakken kits again.


Posted by: Collin Cunningham on February 1, 2009 at 2:30 PM

@Derek - It does work, as I've used it myself. But there's a reason it's not called an "audio" or "mic" input - try boosting your signal with a battery powered amp or similar before plugging in.


Posted by: The Bark Petition on February 21, 2009 at 3:09 PM

Input Port Keyboard Control

I added an RCA port to the SX-150 to make it easy to connect different controllers and devices. Here's video:

http://www.youtube.com/watch?v=W7yj1e1isQY


Leave a comment


Subscribe to MAKE!Subscribe to MAKE Magazine!

Subscribe today, save 42% and get web access to MAKE free. MAKE Digital Edition is available only to subscribers.

$34.95 / 1 year
(4 Quarterly Issues)

Subscribe now

How-to videos for Makers and Crafers!


Void your warranty, violate a user agreement, fry a circuit, blow a fuse, poke an eye out. Make: The risk-takers, the doers, the makers of things... Welcome to Make: Online!


CRAFT Maker Shed Maker Faire MAKE television
MAKE: en Español MAKE: Japan

Make: television
Make: television is here! Visit makezine.tv or iTunes to see all the episodes.

Connect with MAKE

Be a MAKE fan on Facebook MAKE on Facebook
Visit our Facebook page and become a fan of MAKE!
MAKE on Twitter MAKE on Twitter
Follow our MAKE tweets!
MAKE Flickr Pool MAKE on Flickr
Join our MAKE Flickr Pool!
    make_tips on Twitter

    MAKE's RSS feed is here.
    Add MAKE to iGoogle - GoogleGoogle.
    How to add MAKE to your RSS reader - Real simple.
    Add MAKE on FriendFeed


    Advertise here with FM.

    Why advertise on MAKE?
    Read what folks are saying about us!

    Click here to advertise on MAKE!

    MAKE wins Treehugger Best of Green Award

    MAKE wins Brit Insurance Design Award

    Subscribe to MAKE Magazine!

    Make: Online authors!

    Gareth Branwyn, Chris Connors (guest author), Collin Cunningham, Marc de Vinck, Peter Horvath (intern), Kip Kay, Goli Mohammadi, John Park, Sean Ragan, Becky Stern, Phillip Torrone

    Suggest a Site!

    Current Podcast

    itunesdl.gif Weekend Project: Fire Piston Make your own fire starter that uses compressed air and burns at 500 degrees! Thanks to Bill Gurstelle for showing us this at Maker Faire. To download The Fire Piston MP4 click here or subscribe in iTunes. Pick up... More...

    Get the Make: Online sent via email
    Enter your email to receive Make: Online each day:






    Subscribe to MAKE Magazine!

    Recent Posts from the Craft: Blog