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Synthesizers

Posted: Fri May 23, 2008 3:56 am
by Brent
Some things beg to be shared. Analog synthesizers are some of them.

The first guy is Dr. Bob Moog. He is one of the greats for the analog synthesizers. In this particular video he does a demo of the Minimoog’s makeup
http://youtube.com/watch?v=0z0cbMkOvY0&feature=related

But I found in order to see what the Minimoog can actually do, you have to see this video
of Józef Skrzek playing a Minimoog solo.
http://www.youtube.com/watch?v=L6p41HBn2ic&NR=1

Of course there are were also many other forms of synths. I love this video in particular due to the crazy personality playing the tunes.
Minimoog & Minimoog Voyager Side-by-Side
http://youtube.com/watch?v=bMMaIEEFU6I&feature=related

And finally, the last of the analog generation before going digital, the Oberheim Xpander. This is a great video by 123Synth.
http://youtube.com/watch?v=EpnAlSASlBU&feature=related

I have yet to study POPs, and I am no electrician or electrical engineer, so I have no idea what relevance this could have to the project.

Posted: Fri May 23, 2008 4:54 am
by MSimon
Digital synths will probably be the way to go. You can form the wave on a bit by bit basis.

Look up:

Arbitrary Waveform Generator

About 10 to 20 samples per cycle should give pretty good fidelity (with filtering) clock it at 100 MHz and you get 5 to 10 MHz. About right for small experiments.

A 100 MW 2 m reaction space machine @ 50 KV drive would allow for about 500 to 1,000 samples per cycle. Very good fidelity indeed.

Amateur analog synths. Look up:

Southwest Technical Products

Posted: Fri May 23, 2008 5:17 am
by Brent
Thanks. This looks interesting!

Note: I edited my first post, along with the title, since I am becoming notoriously bad a making typographical/spelling errors. I misspelled synth and synthesizer.

Posted: Fri May 23, 2008 5:23 am
by MSimon
Brent,

I love the editing feature.

However, we have yet to have a spelling war here.

Posted: Fri May 23, 2008 5:12 pm
by hanelyp
When you mention synthesizer and POPS together, I think Phase Locked Loop, adjusting POPS drive to match whatever the natural resonant resonant frequency is. Get the drive X hertz off in a high Q loosely coupled resonator and you get an amplitude modulated ringing at X hertz. I don't know how high the POPS Q would be or how tightly coupled the drive would be.

Posted: Fri May 23, 2008 5:36 pm
by JohnP
Hee...

I put out 4 CD's in the past several years and produced a 5th as a compilation of mine & other people's work:

http://cdbaby.com/group/mnml

They've done a lot of great things with digital over the years but analog has a lot of life left in it. Call me old fashioned but it's also a lot more fun to use real patch cords etc.

Posted: Fri May 23, 2008 6:12 pm
by MSimon
hanelyp wrote:When you mention synthesizer and POPS together, I think Phase Locked Loop, adjusting POPS drive to match whatever the natural resonant resonant frequency is. Get the drive X hertz off in a high Q loosely coupled resonator and you get an amplitude modulated ringing at X hertz. I don't know how high the POPS Q would be or how tightly coupled the drive would be.
That is a very good idea and I had considered it at first. However, my current preference is for a high frequency ion detector. Although a PLL to multiply the frequency to run the arb might be a requirement.

BTW I love PLLs. Such fun.

A secondary PLL with a phase detector (I like the Tayloe these days due to the low noise) and a pilot frequency to keep the DC voltage centered on the pB11 resonance peak might be a requirement.

Getting the BFR lash up to hum with all the interlocking rqmts will be quite a trick.

I love this stuff!!!!!!!! Such interesting problems.

Posted: Sat May 24, 2008 1:07 am
by Brent
JohnP wrote:Hee...

I put out 4 CD's in the past several years and produced a 5th as a compilation of mine & other people's work:

http://cdbaby.com/group/mnml

They've done a lot of great things with digital over the years but analog has a lot of life left in it. Call me old fashioned but it's also a lot more fun to use real patch cords etc.
John,

It looks like you are producing some pretty mean sounds. Thanks for the link!

I'm just beginning to get into synthesizers. I recently bought Synthesizer Programming by Dominic Milano. It seemed like a good buy. Now the $$ to pick up a synthesizer. hmm... lol ... I guess I'll have to work on that one.

Posted: Sat May 24, 2008 1:27 am
by Brent
I'd like to get an Oberheim Xpander one of these days, it seems like a very sweet instrument.

Posted: Sat May 24, 2008 2:58 am
by drmike
Building synths and waveform generators is fun, but I really admire those who can actually make music with them. My latest "synth" is a 2000 channel nerve stimulator with 10 MHz update rates on each channel (but only 1.6 milliseconds for the full wave form time). I can't imagine what somebody could do with a 2000 tone generator, but I suspect it wouldn't be enough for some of you guys.

Digital synths can be just as artistic as analog ones, but they can also be too boring because they replicate things every time and analog is just close - it's really different every time you turn it on. With enough horse power a digital synth can do everything an analog one can do with the advantage of being repeatable.

But I repeat - I really am impressed by the ability to make music with a bunch of op amps and a few knobs!!

Posted: Tue May 27, 2008 1:21 am
by Brent
drmike,

I remember hearing about this nerve simulation. Is it coming along pretty well?

Posted: Tue May 27, 2008 12:53 pm
by drmike
Yes and no. We can prove it works to the EU, but the FDA isn't too happy with us. Yet. But the guys who invented the idea have a lot more, and I suspect this is only the tip of a really big connection between electronics and humans.

Posted: Tue Jun 03, 2008 5:00 am
by Brent
I think Galileo, and the trouble he faced being accepted. Yet, he was a great scientist. ..."ditto" with the last person does not promote advancement, only something original it seems. ....so to me, you're well on your way.

I found the strangest thing when searching for second virial coefficients.
A paper by the Royal Society of Chemistry that speaks of neural networks:

http://www.rsc.org/ej/CP/2001/b105183k.pdf
Efficient estimation of second virial coefficients of fused hard-sphere
molecules by an artificial neural network

Posted: Tue Jun 03, 2008 1:59 pm
by drmike
Yup, I think every method of estimation should be tried on every measurement. Should keep people busy writing papers for a long time! And every now and then we'll come up with a new discovery by accident too.

Posted: Thu Jun 05, 2008 3:16 am
by Roger
BRent,

Remember the ARP ?

I bought a Fender tube amp brand new about 5 yrs ago, for my guitar, I drop a mike in front of it and blend the feedback back in with an electric eye, Morely pedal.

AS a side note vinyl record sales are back up to 1 million copies. Turntables are hot again.