Doepfer

Hi

I've just got an A-111.5 and love the sound, however I have a problem with the tuning. Its mounted in a LC9 case, I tuned it on middle c using a tuner. When you play up the keyboard the tuning drifts upwards (+20% at +2 octaves) and when you play down the keyboard the tuning drifts downwards(-10% at -2 octaves).

Hope this makes sense, my A-110 VCO's track perfectly using the same A-190.2.

Thanks in advance

Mark

> Hi
>
> I've just got an A-111.5 and love the sound, however I have a
> problem with the tuning. Its mounted in a LC9 case, I tuned it on
> middle c using a tuner. When you play up the keyboard the tuning
> drifts upwards (+20% at +2 octaves) and when you play down the
> keyboard the tuning drifts downwards(-10% at -2 octaves).
>
> Hope this makes sense, my A-110 VCO's track perfectly using the
> same A-190.2.
>
> Thanks in advance
>
> Mark

Probably the VCO scale has to be readjusted. Details in the appendix of the
A-111-5 user's manual (P17).

Best wishes
Dieter Doepfer

Hi

Thanks, I got Andy at EMIS to check it for me, it was only slightly out so I'll see what it does when it's back in my system

Thanks

Mark

--- In Doepfer_a100@yahoogroups.com, <yahoo@...> wrote:

>
> > Hi
> >
> > I've just got an A-111.5 and love the sound, however I have a
> > problem with the tuning. Its mounted in a LC9 case, I tuned it on
> > middle c using a tuner. When you play up the keyboard the tuning
> > drifts upwards (+20% at +2 octaves) and when you play down the
> > keyboard the tuning drifts downwards(-10% at -2 octaves).
> >
> > Hope this makes sense, my A-110 VCO's track perfectly using the
> > same A-190.2.
> >
> > Thanks in advance
> >
> > Mark
> 
> Probably the VCO scale has to be readjusted. Details in the appendix of the
> A-111-5 user's manual (P17).
> 
> Best wishes
> Dieter Doepfer
>

Hello Mark

On 21.05.12 22:21 , mark wrote:
> so I'll see what it does when it's back in my system
Just a word about that: The tuning and octave tracking is depending on 
the powersupply voltages. You may adjust a VCO in a foreign system to 
about 99% of its abilities, but the last 1% is only reachable, if you 
adjust it connected to the powersupply with which it will work in the 
future.

So I suggest, that you bring at least that rack to EMIS, where the VCO 
is attached to.

Florian

> Hello Mark
>
> On 21.05.12 22:21 , mark wrote:
> > so I'll see what it does when it's back in my system
> Just a word about that: The tuning and octave tracking is depending on
> the powersupply voltages. You may adjust a VCO in a foreign system to
> about 99% of its abilities, but the last 1% is only reachable, if you
> adjust it connected to the powersupply with which it will work in the
> future.
>
> So I suggest, that you bring at least that rack to EMIS, where the VCO
> is attached to.
>
> Florian

I don't think that this applies to the A-111-5 because it has additional
internal voltage regulators for the CEM3394 available. The internal supplies
for the CEM3394 are +8V and -5V. Even all tuning controls for the VCO
(octave switches, tuning control at the front panel, internal offset
frequency trimming potentiometer) are connected to the internal +8V
and/or -5V. But for other VCOs it's correct - provided that not the
A-100PSU2 is used. The A-100PSU2 is adjusted in the factory to +/-12,00V
within +/-10mV so that the supply voltage tolerances should not affect the
VCOs. But for simple supplies (e.g. with 7812/7912 regulators only or for
switching power supplies) the supply voltages may affect the VCO tuning.

Best wishes
Dieter Doepfer

Hi

Thanks,

It's come back and it's still out by 10% at two octaves above middle c and 20% two octaves below middle c. Andy emailed me to say it was spot on when he recalibrared it. 

Mark


--- In Doepfer_a100@yahoogroups.com, <yahoo@...> wrote:

>
> > Hello Mark
> >
> > On 21.05.12 22:21 , mark wrote:
> > > so I'll see what it does when it's back in my system
> > Just a word about that: The tuning and octave tracking is depending on
> > the powersupply voltages. You may adjust a VCO in a foreign system to
> > about 99% of its abilities, but the last 1% is only reachable, if you
> > adjust it connected to the powersupply with which it will work in the
> > future.
> >
> > So I suggest, that you bring at least that rack to EMIS, where the VCO
> > is attached to.
> >
> > Florian
> 
> I don't think that this applies to the A-111-5 because it has additional
> internal voltage regulators for the CEM3394 available. The internal supplies
> for the CEM3394 are +8V and -5V. Even all tuning controls for the VCO
> (octave switches, tuning control at the front panel, internal offset
> frequency trimming potentiometer) are connected to the internal +8V
> and/or -5V. But for other VCOs it's correct - provided that not the
> A-100PSU2 is used. The A-100PSU2 is adjusted in the factory to +/-12,00V
> within +/-10mV so that the supply voltage tolerances should not affect the
> VCOs. But for simple supplies (e.g. with 7812/7912 regulators only or for
> switching power supplies) the supply voltages may affect the VCO tuning.
> 
> Best wishes
> Dieter Doepfer
>

> Hi
> 
> Thanks,
> 
> It's come back and it's still out by 10% at two octaves above 
> middle c and 20% two octaves below middle c. Andy emailed me to 
> say it was spot on when he recalibrared it. 
> 
> Mark

Maybe the problem is not caused by the A-111-5 but the CV source. 

Best wishes
Dieter Doepfer

Hi

I thought that, but it pitches perfectly with 3 other vco's

Mark


--- In Doepfer_a100@yahoogroups.com, <yahoo@...> wrote:

>
> > Hi
> > 
> > Thanks,
> > 
> > It's come back and it's still out by 10% at two octaves above 
> > middle c and 20% two octaves below middle c. Andy emailed me to 
> > say it was spot on when he recalibrared it. 
> > 
> > Mark
> 
> Maybe the problem is not caused by the A-111-5 but the CV source. 
> 
> Best wishes
> Dieter Doepfer
>

Probably a stupid question, but just to make sure...

These 3 other VCOs plus the new one aren't all being controlled from the same bus without the CV signal being boosted first, are they?  I've just installed a third oscillator, and now the one furthest from the pitch CV output is really out tuning wise, but I gather that's because I'm not running it through an A-185-1 module.

Hope that helps,
Zoë.

yes, in this occasion, an A185-1 Bus Access will help!

 
Bakis


________________________________

 From: Zoë Blade <zoe@bytenoise.co.uk>
To: Doepfer_a100@yahoogroups.com 
Sent: Thursday, May 24, 2012 9:59 PM
Subject: Re: [Doepfer_a100] A-111.5 tuning problem
 

  
Probably a stupid question, but just to make sure...

These 3 other VCOs plus the new one aren't all being controlled from the same bus without the CV signal being boosted first, are they?  I've just installed a third oscillator, and now the one furthest from the pitch CV output is really out tuning wise, but I gather that's because I'm not running it through an A-185-1 module.

Hope that helps,
Zoë.
 

[Non-text portions of this message have been removed]

Hi

Even when I have it as the only vco on the bus board it's still out. 

Mark 

--- In Doepfer_a100@yahoogroups.com, Zoë Blade <zoe@...> wrote:

>
> Probably a stupid question, but just to make sure...
> 
> These 3 other VCOs plus the new one aren't all being controlled from the same bus without the CV signal being boosted first, are they?  I've just installed a third oscillator, and now the one furthest from the pitch CV output is really out tuning wise, but I gather that's because I'm not running it through an A-185-1 module.
> 
> Hope that helps,
> Zoë.
>

> Hi
>
> I thought that, but it pitches perfectly with 3 other vco's
>
> Mark

To find out what's wrong one has to measure at first the control CV if it's
exactly 1.000V/octave (digital multimeter with at least 3 1/2 digits, better
4 1/2). Maybe it's a bit off and the three other VCOs were adjusted with
this slightly wrong CV.

Best wishes
Dieter Doepfer

Hi

Well, I was brave enough to calibrate it myself an I've got it within acceptable tolerances. I'll try measuring the cv outputs later, but for now I'm just gonna make some noise 😃

Thanks for everyone's help and suggestions. 

Mark

--- In Doepfer_a100@yahoogroups.com, <yahoo@...> wrote:

>
> > Hi
> >
> > I thought that, but it pitches perfectly with 3 other vco's
> >
> > Mark
> 
> To find out what's wrong one has to measure at first the control CV if it's
> exactly 1.000V/octave (digital multimeter with at least 3 1/2 digits, better
> 4 1/2). Maybe it's a bit off and the three other VCOs were adjusted with
> this slightly wrong CV.
> 
> Best wishes
> Dieter Doepfer
>

> Hi
>
> Well, I was brave enough to calibrate it myself an I've got it
> within acceptable tolerances. I'll try measuring the cv outputs
> later, but for now I'm just gonna make some noise 😃
>
> Thanks for everyone's help and suggestions.
>
> Mark

I suppose that your CV source (Midi-toCV ?) is a bit out of scale and the
two existing VCOs were adjusted to fit to the interface. This would explain
why the adjustment of the A-111-5 by Andy of Emis did not exactly match to
your CV source. When you have time I'd (and the measuring equipment) I'd
recommend to measure the CV source some day to avoid problems with other
VCOs in the future.

Best wishes
Dieter Doepfer