| Author | Message | ||
| hydrargyrum
Senior Member Username: hydrargyrum Post Number: 889 Registered: 3-2004 |
This question may be out out of left field, but does anyone know if the Variable State Filter from Craig Anderton's "Electronics Projects for Musisicians" was the inspiration for the SF-2? I'm guessing that it may be a case of independent evolution of similar ideas to fit a specific purpose, but the two seem remarkably similar. The Anderton effect is a bank consisting of a Dry signal control, with three independent filters (low, high, and band pass), which are mixed with resonance and frequency controls. My curiosity was piqued because I'm thinking about building the project from the book which also incorporates the Envelope Follower to build a super crazy auto-wah. | ||
| sonicus
Senior Member Username: sonicus Post Number: 1450 Registered: 5-2009 |
I remember that book. I still have it here some where . Now that you have stirred my interest in this again as well , I must find it. I think there have been a few variations of state variable filters with various different particular specs along with a host of monikers and names to add to the semantic puzzle. | ||
| mica
Moderator Username: mica Post Number: 7082 Registered: 6-2000 |
The inspiration for the SF-2 was we figured we could cut the cost by 75% of putting the Superfilters onboard by putting them in a rack unit - there's just a lot more room than inside the body of a bass or guitar. My dad's interest in filters came from when he worked at Ampex in the late sixties. We purchased "Universal Active Filters" from KTI. Academics later termed these "state variable filters" but they are the same animal as I understand. We still have all the handbooks and datasheets from the late sixties in my dad's library. The first Superfilter not installed in a bass was made in about 1970. There is a picture of my dad with one of the first ones he made on Ikebe's website. After the KTI filters weren't available anymore, we began making our own. We installed KTI and ones we made in instruments and as outboard units like the one in the picture. I don't think my dad has Craig Anderton's book, so I suspect your independent evolution theory is correct. Dad has always told me the stuff to invent things is around for years and years, just waiting for someone to put it together. | ||
| elwoodblue
Senior Member Username: elwoodblue Post Number: 1146 Registered: 6-2002 |
Thanks for the info and link Mica, apologies for the sidetrack, what is being made here? | ||
| ajdover
Senior Member Username: ajdover Post Number: 893 Registered: 11-2003 |
I'm not personally concerned where the idea (for the SF-2) came from, but I can understand and respect why others would be. All I know is that I'm glad I have an SF-2 in my rack - it makes every bass I own sound better to my ears. And Kevin, if you build something along the lines of Anderton, I'd love to hear it - it would be interesting to see a comparison of an SF-2 and the unit you might build. Alan | ||
| afrobeat_fool
Advanced Member Username: afrobeat_fool Post Number: 278 Registered: 7-2009 |
Those look like sanding blocks. Very cool sanding blocks. | ||
| elwoodblue
Senior Member Username: elwoodblue Post Number: 1147 Registered: 6-2002 |
gotcha, that makes sense. thanks Nick (I'm also very happy to have an SF-2 in my rack) | ||
| hydrargyrum
Senior Member Username: hydrargyrum Post Number: 890 Registered: 3-2004 |
Thank you so much for the reply Mica. I was just checking the copyright on the Anderton book, and saw it was 1975 (I guess I could have done that in the first place). There were some great photos in that link. Alan: I'm extremely tempted by the Anderton filter. Unfortunately some of the IC chips referenced in the book are no longer in production (I'm not sure if the ones in this project are or not yet), so it may require some additional homework to get it going. It's also second in line after I build a modified pt-80 delay. And my friend wants a David Gilmour style board pretty badly, so it may be a while down the road. But hey, at least I've got lot's of fun projects planned to keep me out of trouble. | ||
| sonicus
Senior Member Username: sonicus Post Number: 1453 Registered: 5-2009 |
Ebay can be a swell resource for finding "new old stock" semiconductors / chips etc... I found a lot sale of RCA 3018 a while back! | ||
| terryc
Senior Member Username: terryc Post Number: 1437 Registered: 11-2004 |
Is there a translator for the website, reminds me of my visit 10 years ago(is it that long!!!) | ||
| sonicus
Senior Member Username: sonicus Post Number: 1461 Registered: 5-2009 |
This may be of interest ; http://www.beis.de/Elektronik/AudioMeasure/UniversalFilter.html http://focus.ti.com/docs/prod/folders/print/uaf42.html | ||
| hydrargyrum
Senior Member Username: hydrargyrum Post Number: 892 Registered: 3-2004 |
Very cool! Thanks for the links. | ||
| jacko
Senior Member Username: jacko Post Number: 2812 Registered: 10-2002 |
Nice Pic Mica. Your dad Always looks happy. graeme | ||
| edwin
Senior Member Username: edwin Post Number: 816 Registered: 5-2002 |
I built one of Craig's filters back in 1983 or so into a bass I had. It was kind of finicky, but very cool. The resonance could be turned up to the point of oscillation and the frequencies could go subsonic. I think I still have it in a box somewhere and maybe I could wire it up to be more reliable now that I have much better soldering skills. All in all, it was a cool effect and I had ideas at one point of combining it with his envelope follower. PAIA used to have circuit boards and kits for these projects. I'm not sure if they still do. | ||
| slicknickhaas
Junior Username: slicknickhaas Post Number: 35 Registered: 10-2009 |
Isn't the SF-2 some what inspired by George Mundy's Pluto Tone Fliter pedal? Phil used one in the early years with Big Brown. but the SF-2 and Pluto pedal seem to have a lot in common, the pluto has some sort of wah pedal wired with it whitch seems like a great idea to me. | ||
| sonicus
Senior Member Username: sonicus Post Number: 1541 Registered: 5-2009 |
Mr. George Mundy Installed a version of his Pluto Filters into MY old Bass; http://alembic.com/club/messages/411/2792.html?1262960781 At that time I had the opportunity to try out a Pluto Pedal during a visit with Mr. Mundy. The pedal was designed to work in two directions. I had fun playing with it. It is a variation of a "STATE VARIABLE FILTER". He did this at about the time that Mr. Phil Lesh was getting his "Osage Alembic" wired with a more substantial electronics package.I remember seeing Phil's Bass on the work bench in progress. In my opinion the Alembic SF-2 is the most useful and musical variation of a " STATE VARIABLE FLTER" to date. A handy little device______I love mine . | ||
| slicknickhaas
Junior Username: slicknickhaas Post Number: 37 Registered: 10-2009 |
Any one know what happend to George Mundy? or on the same note where's that bass made of osage? | ||
| sonicus
Senior Member Username: sonicus Post Number: 1543 Registered: 5-2009 |
I recently spoke with the current owner of my old Guild/Alembic with Pluto Filters ( see the link this thread my post #1541) and told me that he is in contact with Mr.George Mundy. I have to add that Mr. Mundy was really cool at the time when he installed his filters into my Bass . In my experience he is a highly intelligent and knowledgeable gentleman . I at the time was an audio engineering student with many questions. I am still grateful for his patience that he exhibited towards me. Thanks George________ I would still have that Bass if I would not have gone through that period of difficult financial times in 1978! | ||
| slicknickhaas
Junior Username: slicknickhaas Post Number: 38 Registered: 10-2009 |
Ive been trying to find a way to contact George for some time now, I wasn't sure if he was still around or not. |
