Doepfer

hello,

i have a serious problem with my a129/5 module.
no matter what signal i feed into the input,
the output is heavily distorted and far too loud,
even when the gain of the a129/5 is set to zero.
i'm 100% sure that the signal presented to the a129/5 input
is perfectly clean and undistorted.

all pots are working normal, the treble emphasizes the high
frequencies and the gain makes the signal louder,
but the output is always unusably distorted.
the voiced/unvoiced detector seems to work ok.
the only thing i can do is reducing the input signal
to near silence. then the distortion stops, but the
voiced/unvoiced decoder stops responding very well.

the a129/5 worked well for years.
do i have to replace it or is there a chance of getting it repaired?
unfortunately dieter doepfer is at the namm show,
so i'm not getting really helpful advices from doepfer.

can anyone give me a hint?

many thanks

self oscillate

hello self,
try contacting roland mayer who's not in the namm
show!he is the technical guy at doepfer
gmbh.(email:technik@doepfer.de or something like
that.see the doepfer site for correct email)
anyway,it looks to me that your a129/5 needs
repair....

bakis.



--- "selfoscillate <synaptic_music@yahoo.com>"
<synaptic_music@yahoo.com> wrote:
> 
> hello,
> 
> i have a serious problem with my a129/5 module.
> no matter what signal i feed into the input,
> the output is heavily distorted and far too loud,
> even when the gain of the a129/5 is set to zero.
> i'm 100% sure that the signal presented to the
> a129/5 input
> is perfectly clean and undistorted.
> 
> all pots are working normal, the treble emphasizes
> the high
> frequencies and the gain makes the signal louder,
> but the output is always unusably distorted.
> the voiced/unvoiced detector seems to work ok.
> the only thing i can do is reducing the input signal
> to near silence. then the distortion stops, but the
> voiced/unvoiced decoder stops responding very well.
> 
> the a129/5 worked well for years.
> do i have to replace it or is there a chance of
> getting it repaired?
> unfortunately dieter doepfer is at the namm show,
> so i'm not getting really helpful advices from
> doepfer.
> 
> can anyone give me a hint?
> 
> many thanks
> 
> self oscillate
> 
> 
> 


=====
synthfreak(parallel worlds)
athens-greece
[Doepfer_a100] group owner-moderator

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HI selfoscillate 

> do i have to replace it or is there a chance of getting it repaired?
> unfortunately dieter doepfer is at the namm show,
> so i'm not getting really helpful advices from doepfer.
Which output is distorted? The "speech out" or the switched output?

Florian

Hi Self oscillate,

I don't have one of these, but from it's description I'd guess the 
audio input gets split into two paths: one through an amplifier and 
filter for the treble boost, and then out; the other presumably 
splits off after the treble boost to go through another filter doing 
the voiced/unvoiced detection, which then switches the other inputs 
and supplies the gate. It sounds like something in the audio path has 
got screwed up in some way, which is what is giving way too much 
amplification, and hence distortion. Turning the input signal down 
externally would then alleviate this, but would also probably give 
the voiced/unvoiced detection some difficulty, which seems to fit 
your symptoms.

> the a129/5 worked well for years.
> do i have to replace it or is there a chance of getting it repaired?
> unfortunately dieter doepfer is at the namm show,
> so i'm not getting really helpful advices from doepfer.

It's probably fixable (it could even be as simple as replacing a 
chip). Whether you will need to get it back to your local distributor 
(and perhaps then back to Doepfer), or can get someone locally to do 
it I don't know, depends on where you are I guess (in the UK the guy 
who runs EMIS does some repairs himself, which is obviously quicker 
than sending it all the way back to Germany...)

Tim

--- In Doepfer_a100@yahoogroups.com, Florian Anwander 
<Florian.Anwander@c...> wrote:
> HI selfoscillate 
> 
> > do i have to replace it or is there a chance of getting it 
repaired?
> > unfortunately dieter doepfer is at the namm show,
> > so i'm not getting really helpful advices from doepfer.
> Which output is distorted? The "speech out" or the switched output?
> 
> Florian

thanks to everybody.
this group is really nice :-)

it is the speech output which is distorted.
roland mayer wrote, that the speech input is very sensitive, but
it shouldn't be that sensitive at all.

i have to test the switched output once more to verify that
it is really working correctly.

i'll be back soon with the results.

thanks again

self oscillate

Hi selfoscillate

> it is the speech output which is distorted.

> roland mayer wrote, that the speech input is very sensitive, but
> it shouldn't be that sensitive at all.
Did you try already to send a plain microphone signal into the Module?

If a microphone signal distorts also:
remove the module from the case and have a close look at the soldering side
of the pcb. This "sounds" like some ground connection in the circuit is
missing. Start with the solderpoints of the input socket, follow the lines
theat lead away from the socket, check the solderpoints at the end of the
lines and in the close surrounding of that ends. If it is a missing
ground/bad soldering and if the switching itself works, then it has to be
at the first stage after the input.

Florian
-- 
Florian Anwander                  |ConSol*  HP-Support
Tel.   +49.89.45841-133           |Consulting&Solutions Software GmbH
Fax    +49.89.45841-139           |Franziskanerstr. 38, D-81669 München
email: florian.anwander@consol.de |http://www.consol.de

i'll have a closer look at it, thanks for the hint.

best wishes

self oscillate



--- In Doepfer_a100@yahoogroups.com, Florian Anwander 
<Florian.Anwander@c...> wrote:
> Hi selfoscillate
> 
> > it is the speech output which is distorted.
> 
> > roland mayer wrote, that the speech input is very sensitive, but
> > it shouldn't be that sensitive at all.
> Did you try already to send a plain microphone signal into the 
Module?
> 
> If a microphone signal distorts also:
> remove the module from the case and have a close look at the 
soldering side
> of the pcb. This "sounds" like some ground connection in the 
circuit is
> missing. Start with the solderpoints of the input socket, follow 
the lines
> theat lead away from the socket, check the solderpoints at the end 
of the
> lines and in the close surrounding of that ends. If it is a missing
> ground/bad soldering and if the switching itself works, then it has 
to be
> at the first stage after the input.
> 
> Florian
> -- 
> Florian Anwander                  |ConSol*  HP-Support
> Tel.   +49.89.45841-133           |Consulting&Solutions Software 
GmbH
> Fax    +49.89.45841-139           |Franziskanerstr. 38, D-81669 
München
> email: florian.anwander@c... |http://www.consol.de

oh well, i was wrong.
seems that i urgently need a holiday.
the a129/5 works fine, when i use low level signals.
sorry.

best wishes

self oscillate



--- In Doepfer_a100@yahoogroups.com, "selfoscillate 
<synaptic_music@y...>" <synaptic_music@y...> wrote:
> 
> i'll have a closer look at it, thanks for the hint.
> 
> best wishes
> 
> self oscillate
> 
> 
> 
> --- In Doepfer_a100@yahoogroups.com, Florian Anwander 
> <Florian.Anwander@c...> wrote:
> > Hi selfoscillate
> > 
> > > it is the speech output which is distorted.
> > 
> > > roland mayer wrote, that the speech input is very sensitive, but
> > > it shouldn't be that sensitive at all.
> > Did you try already to send a plain microphone signal into the 
> Module?
> > 
> > If a microphone signal distorts also:
> > remove the module from the case and have a close look at the 
> soldering side
> > of the pcb. This "sounds" like some ground connection in the 
> circuit is
> > missing. Start with the solderpoints of the input socket, follow 
> the lines
> > theat lead away from the socket, check the solderpoints at the 
end 
> of the
> > lines and in the close surrounding of that ends. If it is a 
missing
> > ground/bad soldering and if the switching itself works, then it 
has 

> to be
> > at the first stage after the input.
> > 
> > Florian
> > -- 
> > Florian Anwander                  |ConSol*  HP-Support
> > Tel.   +49.89.45841-133           |Consulting&Solutions Software 
> GmbH
> > Fax    +49.89.45841-139           |Franziskanerstr. 38, D-81669 
> München
> > email: florian.anwander@c... |http://www.consol.de