MOTM

On paper I have the VCLFO designed. *Curently*, it is designed to be a 1U,
single VCLFO as follows:

4 controls
--------------

Initial Speed (from about 1 cylce in 20 seconds to 4Khz)
CV Speed attenuator that is a reversing attenuator (ie increasing voltage
makes it faster or slower than INITIAL)
Shape: this is a symmetry control that effects all waveforms simultaneously.
At 12:00 then everything is 50%.
Output select: 4 position rotary switch: Sine, Tri, Ramp, and Pulse

4 Jacks
-----------

CV Speed
CV Shape
OUT +
OUT -

1 LED: this is a special "analog" LED that continuously changes *colors* at
the LFO rate. It does not
"blink": it's always on. This is because blinking can introduce curent
glitches that a VCO can pickup
(can you say "ASM-1").

Estimated price for this configuration: $99 kit $139 assembled.

However, I can make this a 2U wide as follows:

add a SHAPE attenuator (note that there is NOT on on the 1U)
4 individual outputs (like the VCO)
2 Speed CV inputs
HI/LO range switch LO = 1 cycle in 1 minute to 900Hz HI as above

Estimate price for this configuration (everything else same: LED, etc) is
$135 kit $190 assembled

Send in you vote/comments.

Paul S.

I vote for single space $99 kit. However, as always, I will buy which ever
one you make.
Larry Hendry


----------

> From: Paul Schreiber <synth1@...>
> To: MOTM listserv <motm@onelist.com>
> Subject: [motm] Vote for VCLFO design!
> Date: Sunday, May 02, 1999 6:01 PM
>
> From: "Paul Schreiber" <synth1@...>
>
> On paper I have the VCLFO designed. *Curently*, it is designed to be a

1U,

> single VCLFO as follows:
>
> 4 controls
> --------------
>
> Initial Speed (from about 1 cylce in 20 seconds to 4Khz)
> CV Speed attenuator that is a reversing attenuator (ie increasing voltage
> makes it faster or slower than INITIAL)
> Shape: this is a symmetry control that effects all waveforms

simultaneously.

> At 12:00 then everything is 50%.
> Output select: 4 position rotary switch: Sine, Tri, Ramp, and Pulse
>
> 4 Jacks
> -----------
>
> CV Speed
> CV Shape
> OUT +
> OUT -
>
> 1 LED: this is a special "analog" LED that continuously changes *colors*

at

> the LFO rate. It does not
> "blink": it's always on. This is because blinking can introduce curent
> glitches that a VCO can pickup
> (can you say "ASM-1").
>
> Estimated price for this configuration: $99 kit $139 assembled.
>
> However, I can make this a 2U wide as follows:
>
> add a SHAPE attenuator (note that there is NOT on on the 1U)
> 4 individual outputs (like the VCO)
> 2 Speed CV inputs
> HI/LO range switch LO = 1 cycle in 1 minute to 900Hz HI as above
>
> Estimate price for this configuration (everything else same: LED, etc) is
> $135 kit $190 assembled
>
> Send in you vote/comments.
>
> Paul S.
>
>
>
> ------------------------------------------------------------------------
> Share the wealth!
> http://www.ONElist.com
> Tell a friend about ONElist's 130,000 free e-mail communities!

I am still not good with describing and understanding everything. Is it
possible to sync the LFO with other things? Is it possible to vary the
amount of phase it of sync with another source? If you do a 2U version, is
it possible to add a button to retrigger manually? This is especially nice
for doing longer cycles for drones, ambiences, etc. A trigger in would also
be nice. If this is already implied, forgive my ignorance.

> Initial Speed (from about 1 cycle in 20 seconds to 4Khz)
> At 12:00 then everything is 50%.
> Output select: 4 position rotary switch: Sine, Tri, Ramp, and Pulse

So what are the effective min and max speeds of the LFO? What would these
numbers be for the 2U version? Any way to reverse the direction of the
ramp? What percentage is the pulse set at? Does this differ from PWM? Is
this more akin to a trigger?

> 1 LED: this is a special "analog" LED that continuously changes *colors*

at the LFO rate. It does not "blink": it's always on. This is because
blinking can introduce current glitches that a VCO can pickup (can you say
"ASM-1").

This LED is a MOTM classic in the making. I love the changing color idea;
two or three colors? I am assuming there is essentially no lag; it responds
almost instantaneously?

> Estimated price for this configuration: $99 kit $139 assembled. However,

I can make this a 2U wide as follows: Estimate price for this configuration
(everything else same: LED, etc) is $135 kit $190 assembled

Paul, both sound great--price and functionality. What are the odds of you
making both? Put me down for (at least) one of each if you do. I love the
idea of 1U modules; but when it gets down to it, I would rather have maximum
functionality (2U).

The 2U unit have room for a second--extremely limited--LFO on board?

--Todd

Like most other people here, I'm sure I'd build whatever you design, but I
guess I'd prefer the 1U model, given that I'd probably want at least a
couple of them.

BTW, I can't think of any other synth maker that actually lets their
customers vote on synth designs. Right on!

________________________________________________________
Dave Trenkel : improv@... : www.peak.org/~improv/

"...there will come a day when you won't have to use
gasoline. You'd simply take a cassette and put it in
your car, let it run. You'd have to have the proper
type of music. Like you take two sticks, put 'em
together, make fire. You take some notes and rub 'em
together - dum, dum, dum, dum - fire, cosmic fire."
-Sun Ra
________________________________________________________

>
>BTW, I can't think of any other synth maker that actually lets their
>customers vote on synth designs. Right on!
>

That's because *I* get all of my modules for free....YOU have to pay for
them.
Why not them pay for what you want?? Plus usually we are in agreement, or in
some
cases you think of a neat feature I never considered.

Paul S.
(VCO pkg should arrive tomorrow!)

>
>
>
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Week!

>

I would want both designs. Very slow cycle times are important to me, and
simultaneous outputs, but I'd have a place in my system for a couple of the
simple LFOs also. If you forced me to vote for just 1 design, I'd favor the
2 space version.

Sync or restart on the 2 spacer would be an important addition also.

Dave Bradley
Principal Software Engineer
Engineering Animation, Inc.
daveb@...

> -----Original Message-----
> From: Paul Schreiber [mailto:synth1@...]
> Sent: Sunday, May 02, 1999 6:01 PM
> To: MOTM listserv
> Subject: [motm] Vote for VCLFO design!
>
>
> From: "Paul Schreiber" <synth1@...>
>
> On paper I have the VCLFO designed. *Curently*, it is designed to be a 1U,
> single VCLFO as follows:
>
> 4 controls
> --------------
>
> Initial Speed (from about 1 cylce in 20 seconds to 4Khz)
> CV Speed attenuator that is a reversing attenuator (ie increasing voltage
> makes it faster or slower than INITIAL)
> Shape: this is a symmetry control that effects all waveforms
> simultaneously.
> At 12:00 then everything is 50%.
> Output select: 4 position rotary switch: Sine, Tri, Ramp, and Pulse
>
> 4 Jacks
> -----------
>
> CV Speed
> CV Shape
> OUT +
> OUT -
>
> 1 LED: this is a special "analog" LED that continuously changes
> *colors* at
> the LFO rate. It does not
> "blink": it's always on. This is because blinking can introduce curent
> glitches that a VCO can pickup
> (can you say "ASM-1").
>
> Estimated price for this configuration: $99 kit $139 assembled.
>
> However, I can make this a 2U wide as follows:
>
> add a SHAPE attenuator (note that there is NOT on on the 1U)
> 4 individual outputs (like the VCO)
> 2 Speed CV inputs
> HI/LO range switch LO = 1 cycle in 1 minute to 900Hz HI as above
>
> Estimate price for this configuration (everything else same: LED, etc) is
> $135 kit $190 assembled
>
> Send in you vote/comments.
>
> Paul S.
>
>
>
> ------------------------------------------------------------------------
> Share the wealth!
> http://www.ONElist.com
> Tell a friend about ONElist's 130,000 free e-mail communities!
>

I tend to vote for a 2U-width type of LFO because :

- a Sync-Input is quite benificial ( for those delayed vibrato type of
modulations )

- CV inputs without an attenuator ( except those keyboard input -
1V/Oct - ones ) are somewhat anoying because You need a a pot from
elsewhere and start to use (CV-) mixers all over

- a HI/LO range switch is a good investment to keep the range to be
covered by the pot to an acceptable value

Gert

>From: "Paul Schreiber" <synth1@...>
>
>On paper I have the VCLFO designed. *Curently*, it is designed to be a 1U,
>single VCLFO as follows:
>
>4 controls
>--------------
>
>Initial Speed (from about 1 cylce in 20 seconds to 4Khz)
>CV Speed attenuator that is a reversing attenuator (ie increasing voltage
>makes it faster or slower than INITIAL)
>Shape: this is a symmetry control that effects all waveforms simultaneously.
>At 12:00 then everything is 50%.
>Output select: 4 position rotary switch: Sine, Tri, Ramp, and Pulse
>
>4 Jacks
>-----------
>
>CV Speed
>CV Shape
>OUT +
>OUT -
>
>1 LED: this is a special "analog" LED that continuously changes *colors* at
>the LFO rate. It does not
>"blink": it's always on. This is because blinking can introduce curent
>glitches that a VCO can pickup
>(can you say "ASM-1").
>
>Estimated price for this configuration: $99 kit $139 assembled.
>
>However, I can make this a 2U wide as follows:
>
>add a SHAPE attenuator (note that there is NOT on on the 1U)
>4 individual outputs (like the VCO)
>2 Speed CV inputs
>HI/LO range switch LO = 1 cycle in 1 minute to 900Hz HI as above
>
>Estimate price for this configuration (everything else same: LED, etc) is
>$135 kit $190 assembled
>
>Send in you vote/comments.
>
>Paul S.
>
>
>
>------------------------------------------------------------------------
>Share the wealth!
>http://www.ONElist.com
>Tell a friend about ONElist's 130,000 free e-mail communities!

Hello All,

I like the idea of a the 2 space LFO, because of the added features.

I'd probably buy both types though.

My concern is about the LED design. If a multi color LED is used, it may
take away from the design continuity.
I'd rather see an LED configuration similar to the MOTM700.
Perhaps the design could utilize 3 or 4 leds that are illuminated to a
certain degree, but the brightness would increase sequentially as the LFO
speed increased. I was picturing something like a "chaser effect" Maybe a
design such as this could eliminate the noise introduction because of an
On-Off switching that Paul had mentioned

Paul, would the multicolor LED use the same housing as the others?

Regards,

Mark Tencza

Well, the early voting favored the 1U, but the 2U faction has come on
strong!

Actually, a 2U is looking better since originally I thought I could fit all
of the circuitry
on the smaller pcb (ie MOTM-800 size) but that's not going to happen!

If we can get Dave Tr. away from his MOTM-300 kits, perhaps he can gen up a
front
panel shot.

Maybe:


LED FREQ

CVMOD WAVE

RANGE SHAPE

SHAPE CV MOD


1V/O CVIN SHAPE IN SYNC
SINE TRI RAMP PULSE


8 jacks, 4 pots, 1 LED, 1 rotary switch, 1 toggle switch, 2U wide

That's in the $135 ballpark. But on the HI range it is a mini VCO, probably
as good as the
ASM-1 or a tomg circuit. It is temperature conensated somewhat, although to
be accurate
you need a 1V/Oct trim pot (currently not there). I guess I can add a 1-turn
trimmer for this.
(the 25-turn ones in the VCOs are $$$).

The LEDS are all bought and paid for! The nice thing about them is that the
leads are pre-soldered
and pre-heatshrinked. The ever astute readers will see a soldering to the
pcb dilemma. I will
probably have 2 "turrent posts" (like on the Power One supply) the LED leads
solder to on the top
of the pc board.

Yes, they are from LUMEX so they have the same press-fit housing with the
lens assembly as the one in the '700
kit.

BTW this will me the MOTM-320 SUPER LFO unless you'all can pick a better
one.

Paul S.

Hi Paul:

I can't decide which is better (2U or 1U). I was thinking that maybe you
could make one PCB for both configurations with two different: panels,
manuals, parts packages, etc..

Everything else sounds great though!

John B.
Even if that LED is driven by the tri through its own amplifier?

In a message dated 5/3/99 3:17:30 PM, synth1@... writes:

>Well, the early voting favored the 1U, but the 2U faction has come on
>
>strong!
>
>
>
>Actually, a 2U is looking better since originally I thought I could fit
>all
>
>of the circuitry
>
>on the smaller pcb (ie MOTM-800 size) but that's not going to happen!
>
>
>
>If we can get Dave Tr. away from his MOTM-300 kits, perhaps he can gen
>up a
>
>front
>
>panel shot.
>
>
>
>Maybe:
>
>
>
>
>
>LED FREQ
>
>
>
>CVMOD WAVE
>
>
>
>RANGE SHAPE
>
>
>
> SHAPE CV MOD
>
>
>
>
>
>1V/O CVIN SHAPE IN SYNC
>
>SINE TRI RAMP PULSE
>
>
>
>
>
>8 jacks, 4 pots, 1 LED, 1 rotary switch, 1 toggle switch, 2U wide
>
>
>
>

> From: "Paul Schreiber" <synth1@...>
>
> Well, the early voting favored the 1U, but the 2U faction has come on
> strong!

Well, as an earlier supporter of the 1U, I must confess I really like the
comments I have heard from other members concerning ideas for the 2U. So,
sign me up for supporting 2U. However, as others have said, I might also
be interested in one of the 1Us also should MOTM ever have 2 LFOs.

As far as naming the 2U, I think "Super LFO" is kind of too easy. Someone
should be able to do better. Besides, if you then made a 1U you might have
to call it the "not so super LFO." Somehow that name just doesn't convey a
good mental picture. <grin>

Larry Hendry

Hi Paul n All !

I'd go for the 2u design, more functionality that way .

Can't see what the "wave" knob does on your last proposal .

On the trimmer : with one extra hole in the pcb, many multiturns
could be accomodated, a single turn in the kit would do . This way
the builder has a choice .

I'd like to see two sync modes : one a hard reset, another one a
reversal, like on the cem3340 . Might open the door to lots of weird
control waveforms . (Only do-able if the osc is based on a triangle i
guess)

One more useful extra could be a gate input to start and stop the lfo
(full cycles), same could be used for a one shot, maybe even giving
counted bursts, with an external counter .

I'm not too crazy about "zero on top" controls . Unless a generous
zero deadband is included, one cannot be sure no voltage seeps
through . The alternative would be a separate input, switch or a
pull-to-invert knob ...

Later .


Keep 'em oscillating :)


Hugo
=

Being able to retrigger the waveform is really exciting to me. Not only for
"typical" techno stuff at the beginning of measures; but other places as
well.

Make sure we can trigger with a input signal of some sorts. If there is an
extra space on the panel; can we please have a trigger button!!!! I have
unused panel real estate! Ha!

I know Paul is pretty practical about things-- especially LEDs. But I
really like the idea of having several LEDs interacting. Fun for the whole
family! Eye-candy A-go-go! Perhaps Paul's eyes never get hungry...? ;-)

Later Alligator,
Todd

P.S. No one ever responded to the min and max LFO cycles on the two switch
settings. What would they be??? Also, could this be used as poor VCO if we
needed to pull it in???

P.P.S. I looks like the 2U unit going to win. Paul, please don't forget
about the 1U unit when things get under control...

The range on LO is about 1 cycle/min to 900Hz. HI is about 1cycle/3sec to
4Khz.

2U has a commanding lead after a late comback!

Also, since there are individual outs there is no WAVE SELECT switch per my
last post.

As far as phase reversal goes, this will be on a VC Quadrature LFO coming in
the fall. This is
non-trival design-wise to get MOTM-type quality.

Lastly, the SYNC will be a 'hard' sync exactly as in the '300 VCO: the
waveform resets to +5V
(as opposed to resetting to ground). This is because of the way the VCO
section is designed.
By playing with the SHAPE control and/or using an 'outboard' reversing
attenuator, you can get
"sync'd upwards sweeps" a la techno.

Paul S.

Any easy way to get the LO low below 1 cycle/min??? 1 cycle/ 5 minutes
would be nice for some of the stuff I do. If it is too difficult, no
problem. Perhaps a third range???

--Todd

> From: "Paul Schreiber" <synth1@...>
>
> The range on LO is about 1 cycle/min to 900Hz. HI is about 1cycle/3sec to
> 4Khz.

This is very difficult to acheive with any sort of repeteability or
wavehape. The problem is that
the (current)/(capacitance) ratio is so small that parasitic effects
dominate. Stuff like reisistance of the capacitor, leakeage,
pcb surface leakage (a small fingerprint is enough to cause the VCO to stop
working at these low speeds).

It CAN be done but you wouldn't want to pay $17 for the Teflon capacitor!

As far as other analog LFOs that claim this type of range: bull-hockey!

Paul S.

-----Original Message-----
From: Tentochi <tentochi@...>
To: motm@onelist.com <motm@onelist.com>
Date: Wednesday, May 05, 1999 7:39 AM
Subject: Re: [motm] Vote for VCLFO design!

>From: "Tentochi" <tentochi@...>
>
>Any easy way to get the LO low below 1 cycle/min??? 1 cycle/ 5 minutes
>would be nice for some of the stuff I do. If it is too difficult, no
>problem. Perhaps a third range???
>
>--Todd
>
>> From: "Paul Schreiber" <synth1@...>
>>
>> The range on LO is about 1 cycle/min to 900Hz. HI is about 1cycle/3sec to
>> 4Khz.
>
>
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