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Frac VCO features?

Frac VCO features?

2007-07-18 by Paul Schreiber

I am about to start the pc layout of the MOTM-1300 Frac VCO.

This is a "same but different" design, because of the SMT nature. Also, all of
the features
of the MOTM-300 will not fit on the 2-width panel.

If you look at the MOTM-1190 VCA, that has:

8 jacks
6 pots

and room in-between the pots for 2 SPDT toggles.

So what I am thinking is as follows:

Jacks:

PWM 1V/Oct FM Sync
Sine Tri Saw Pulse

Pots (using 5):

Coarse Fine
Width PWM
FM

The 2 toggle switches are:

Hard/Soft sync
EXP/LIN FM

So, what is "given up" over a MOTM-300 is AC/DC FM coupling and the second
FM input jack/attenuator.

Comments? Better speak up quick!

Paul S.

Re: [motm] Frac VCO features?

2007-07-18 by TJ

>
> Comments? Better speak up quick!
>

Having a second 1v/oct jack would be handy.
Would really like to see the coarse knob
removed in favor of a range selector, but
I know that won't happen. :)

Terry (Have 2 MOTM Frac modules)Very Nice!

Re: [motm] Frac VCO features?

2007-07-18 by Paul Schreiber

> Having a second 1v/oct jack would be handy.

How so? The Blacet VCO has this. So, you feed the pitch CV into the
first 1V/O jack. What would you put into the second one?

Paul S.

Re: [motm] Frac VCO features?

2007-07-18 by Richard Brewster

Can't you fit a third switch in the space left over by removing the FM2 pot?

Richard Brewster
http://www.pugix.com

Paul Schreiber wrote:
> I am about to start the pc layout of the MOTM-1300 Frac VCO.
>
> This is a "same but different" design, because of the SMT nature. Also, all of
> the features
> of the MOTM-300 will not fit on the 2-width panel.
>
> If you look at the MOTM-1190 VCA, that has:
>
> 8 jacks
> 6 pots
>
> and room in-between the pots for 2 SPDT toggles.
>
> So what I am thinking is as follows:
>
> Jacks:
>
> PWM 1V/Oct FM Sync
> Sine Tri Saw Pulse
>
> Pots (using 5):
>
> Coarse Fine
> Width PWM
> FM
>
> The 2 toggle switches are:
>
> Hard/Soft sync
> EXP/LIN FM
>
> So, what is "given up" over a MOTM-300 is AC/DC FM coupling and the second
> FM input jack/attenuator.
>
> Comments? Better speak up quick!
>
> Paul S.
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>

Re: [motm] Frac VCO features?

2007-07-18 by TJ

On Wed, 18 Jul 2007 01:20:12 -0500, Paul Schreiber <synth1@...>
wrote:

>> Having a second 1v/oct jack would be handy.
>
> How so? The Blacet VCO has this. So, you feed the pitch CV into the
> first 1V/O jack. What would you put into the second one?
>
>
Quite a few patches I use involve sending both a keyboard CV and a CV
from a sequencer or pitch bender. Having a second 1v/oct would be
useful to transpose the sequencer via the keyboard CV. Just a thought.

Terry

Re: Frac VCO features?

2007-07-18 by chad_kettering

Paul,

I think anyone could get around the second FM jack/knob by just using
another mixer and sending this mix into the 1V/OCT jack if one wants
to blend two CV sources into controlling the VCO.

I like the design thus far. Is there room to add the AC/DC switch in
between the knob layout? So you would set it up like the VCA only with
three switches down the middle. Or will this get too cramped for space?

Looking forward to the smaller format VCO's!!

Chad

Re: [motm] Frac VCO features?

2007-07-18 by loopcycle

Paul,

With a 'pot' space available, what features might live there? Maybe one more
pot or toggle? Are you willing to consider a new feature, or do you intend to
"port" existing 300 features over only?

I like the ac/dc coupling on fm1 input of my motm-300.




--- Paul Schreiber <synth1@...> wrote:

> I am about to start the pc layout of the MOTM-1300 Frac VCO.
>
> This is a "same but different" design, because of the SMT nature. Also, all
> of
> the features
> of the MOTM-300 will not fit on the 2-width panel.
>
> If you look at the MOTM-1190 VCA, that has:
>
> 8 jacks
> 6 pots
>
> and room in-between the pots for 2 SPDT toggles.
>
> So what I am thinking is as follows:
>
> Jacks:
>
> PWM 1V/Oct FM Sync
> Sine Tri Saw Pulse
>
> Pots (using 5):
>
> Coarse Fine
> Width PWM
> FM
>
> The 2 toggle switches are:
>
> Hard/Soft sync
> EXP/LIN FM
>
> So, what is "given up" over a MOTM-300 is AC/DC FM coupling and the second
> FM input jack/attenuator.
>
> Comments? Better speak up quick!
>
> Paul S.
>
>
>
>
> Yahoo! Groups Links
>
>
>
>



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Re: [motm] Frac VCO features?

2007-07-18 by Paul Schreiber

a) a pot needs a jack :)

b) the thing that is looking like the most sense is the AC/DC FM coupling.

Paul S.

> With a 'pot' space available, what features might live there? Maybe one more
> pot or toggle? Are you willing to consider a new feature, or do you intend to
> "port" existing 300 features over only?
>
> I like the ac/dc coupling on fm1 input of my motm-300.
>

Re: [motm] Frac VCO features?

2007-07-18 by mmcgrath@synercard.com

As someone will will DEFINATELY buy at least two of these VCOs, the only thing that really concerns me is the lack of an AC/DC coupling selector switch.

The Blacet doesn't include one either, however the 'job' is already done on the PCB - one only needs to wire up a switch and mount it on the panel.

While the panel is already somewhat full, there's still room to place the switch, so I've modded all three of my VCOs with this.

When I think of all the ommissions you discuss, none really present a problem, at least for me and the way I use a VCO. I don't mind sending an exponential CV along with a vibrato CV into a single jack through a mixer. However the AC/DC is something that I think is a big deal.

Thanks! Looking forward to the next run of frac modules. I currently have your Frac Ladder Filter and the frac dual VCA. While the filter is great and certainly has 'that sound' perfectly nailed, I typically stick to my Wiard filters. The VCA however is something extra special - all my other VCAs pale in comparason to yours, for cleanliness and sound qualtiy.

Best wishes,

Michael McGrath
Manager, Engineering & Training Services
HID Identity
T: (819) 777-6687 ext. 3124
C: (613) 614-6753
F: (819) 777-8114
E: mmcgrath@...




"Paul Schreiber" <synth1@...>
Sent by: motm@yahoogroups.com

18/07/2007 10:52 AM

To
"loopcycle" <loopcycle@...>
cc
"MOTM litserv" <motm@yahoogroups.com>
Subject
Re: [motm] Frac VCO features?




a) a pot needs a jack :)

b) the thing that is looking like the most sense is the AC/DC FM coupling.

Paul S.

> With a 'pot' space available, what features might live there? Maybe
one more
> pot or toggle? Are you willing to consider a new feature, or
do you intend to
> "port" existing 300 features over only?
>
> I like the ac/dc coupling on fm1 input of my motm-300.
>




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Re: Frac VCO features?

2007-07-18 by Girts R

Yes, the AC/DC FM coupling is important, imo. What if the Hard/Soft Sync switch acts also
as AC/DC switch? :)

Girts R.


--- In motm@yahoogroups.com, "Paul Schreiber" <synth1@...> wrote:
>
> a) a pot needs a jack :)
>
> b) the thing that is looking like the most sense is the AC/DC FM coupling.
>
> Paul S.
>
> > With a 'pot' space available, what features might live there? Maybe one more
> > pot or toggle? Are you willing to consider a new feature, or do you intend to
> > "port" existing 300 features over only?
> >
> > I like the ac/dc coupling on fm1 input of my motm-300.
> >
>

Re: [motm] Re: Frac VCO features?

2007-07-18 by John Mahoney

At 08:14 AM 7/18/2007, chad_kettering wrote:

>I think anyone could get around the second FM jack/knob by just using
>another mixer and sending this mix into the 1V/OCT jack if one wants
>to blend two CV sources into controlling the VCO. [snip]

In theory, that's right. In practice, it is easier said than done,
requiring a mixer with accurate unity gain for all inputs.

Are MOTM mixers calibrated accurately enough to maintain pitch
tracking? (Dare I ask?! ;-)
--
john


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Re: [motm] Re: Frac VCO features?

2007-07-18 by eric f

Not the 830, but that's because it divides down the inputs according to the documentation. So if you put 3x10 volt signals, the output is at most 12v with all of the knobs on the subsection turned up. This is all from memory, though... I don't have the docs with me at the moment.
cheers,
eric f

John Mahoney <jmahoney@...> wrote:
At 08:14 AM 7/18/2007, chad_kettering wrote:

>I think anyone could get around the second FM jack/knob by just using
>another mixer and sending this mix into the 1V/OCT jack if one wants
>to blend two CV sources into controlling the VCO. [snip]

In theory, that's right. In practice, it is easier said than done,
requiring a mixer with accurate unity gain for all inputs.

Are MOTM mixers calibrated accurately enough to maintain pitch
tracking? (Dare I ask?! ;-)
--
john

--
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Checked by AVG Free Edition.
Version: 7.5.476 / Virus Database: 269.10.8/906 - Release Date: 7/17/2007 6:30 PM


Re: [motm] Re: Frac VCO features?

2007-07-18 by eric f

Not the 830, but that's because it divides down the inputs according to the documentation. So if you put 3x10 volt signals, the output is at most 12v with all of the knobs on the subsection turned up. This is all from memory, though... I don't have the docs with me at the moment.
cheers,
eric f

John Mahoney <jmahoney@...> wrote:
At 08:14 AM 7/18/2007, chad_kettering wrote:

>I think anyone could get around the second FM jack/knob by just using
>another mixer and sending this mix into the 1V/OCT jack if one wants
>to blend two CV sources into controlling the VCO. [snip]

In theory, that's right. In practice, it is easier said than done,
requiring a mixer with accurate unity gain for all inputs.

Are MOTM mixers calibrated accurately enough to maintain pitch
tracking? (Dare I ask?! ;-)
--
john

--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.5.476 / Virus Database: 269.10.8/906 - Release Date: 7/17/2007 6:30 PM