dINgO Pup kit BUILD THREAD

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kante1603
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Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Sun Aug 27, 2017 1:48 am

Hi Joe,

hope you're fine.
A quick question:I use the dingo pup as active fader modules,all working pretty good.
I wonder what would be an appropiate way to have a mute on output?
Following circuit is an interface (line level balanced,input Z is 12kOhms).

Any idea?

Thank you in advance,

Udo.

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Joe Malone
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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Mon Aug 28, 2017 8:23 am

kante1603 wrote:Hi Joe,

hope you're fine.
A quick question:I use the dingo pup as active fader modules,all working pretty good.
I wonder what would be an appropiate way to have a mute on output?
Following circuit is an interface (line level balanced,input Z is 12kOhms).

Any idea?

Thank you in advance,

Udo.


HI Udo. You can do this the same as most mixing desks do.

Place a SPDT switch between the volume pot wiper wire that discounts the wire from the wiper and switches it to 0v.
Joe :-)
JLM Audio
Capturing Audio without Injury

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Mon Aug 28, 2017 4:37 pm

Joe Malone wrote:Place a SPDT switch between the volume pot wiper wire that discounts the wire from the wiper and switches it to 0v.

Thank you Joe,

that's what I thought first.In the real setup it turned out that the end position did not really damp the signal down to "somehow" minus infinity.Then I found that the end position did not measure zero but a couple of ohms left,so that's why I can't reach a real muted position.All good for now,I know even expensive faders do have a switch at their lowest position,and now I know why,hahaha....(except of faderstart when opening or pfl on tearing further down).

Thanks for confirming my thoughts!

Another question: Instead of using the pot as a standard fader,what about if I needed a fader travel from say +/-15 or +/-20dB?
Doable?

Very curious because I want to use the dingo pup as a trim function for my interfaces (adapting them to my real world +4dBu analog gear better),

Best regards,

Udo.

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Joe Malone
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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Mon Aug 28, 2017 7:05 pm

kante1603 wrote:
Joe Malone wrote:Place a SPDT switch between the volume pot wiper wire that discounts the wire from the wiper and switches it to 0v.

Thank you Joe,

that's what I thought first.In the real setup it turned out that the end position did not really damp the signal down to "somehow" minus infinity.Then I found that the end position did not measure zero but a couple of ohms left,so that's why I can't reach a real muted position.All good for now,I know even expensive faders do have a switch at their lowest position,and now I know why,hahaha....(except of faderstart when opening or pfl on tearing further down).

Thanks for confirming my thoughts!

Another question: Instead of using the pot as a standard fader,what about if I needed a fader travel from say +/-15 or +/-20dB?
Doable?

Very curious because I want to use the dingo pup as a trim function for my interfaces (adapting them to my real world +4dBu analog gear better),

Best regards,

Udo.


Set gain trim pot for +15 or +20dB gain
Add a resistor or trim pot in series with the pot wire going to 0v to limit the -dB amount to -15 or -20dB.
Joe :-)

JLM Audio

Capturing Audio without Injury

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Mon Aug 28, 2017 7:44 pm

Joe Malone wrote:Set gain trim pot for +15 or +20dB gain
Add a resistor or trim pot in series with the pot wire going to 0v to limit the -dB amount to -15 or -20dB.

Wow,that was fast,thank you very much Joe!
Will try with a resistance decade to get some values later and report back.
In case of a series trim pot it is wired as rheostat,yes?
Seems I have buy some more dingo pup kits,hahaha......

Best regards,

Udo.

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Tue Aug 29, 2017 2:15 am

It works!

Made some real world measurements,first with the resistance decade to get an idea of a useful value range.
If anyone is interested: For +/-15dB boost or cut it is around 300 ohms.I'll use a trim pot in that position,maybe 500 ohms or 1k.

Next was pot travel.While for a standard fader/pot travel I take log. types it felt not so nice when modding to a+/-15dB setting due to the log. curve vs. pot position.Same for linear pots.I wanted a zero position around the center.
What definetely works is a linear type plus a 1k slugging resistor.Position was close to center for a factor of 1 (or 0dB amplification).
After swapping the 1k to a trim pot I was able to adjust 0dB to pot position centered spot-on.Great!

Thank you for your help again Joe,

Udo.

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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Tue Aug 29, 2017 10:29 am

kante1603 wrote:It works!

Made some real world measurements,first with the resistance decade to get an idea of a useful value range.
If anyone is interested: For +/-15dB boost or cut it is around 300 ohms.I'll use a trim pot in that position,maybe 500 ohms or 1k.

Next was pot travel.While for a standard fader/pot travel I take log. types it felt not so nice when modding to a+/-15dB setting due to the log. curve vs. pot position.Same for linear pots.I wanted a zero position around the center.
What definetely works is a linear type plus a 1k slugging resistor.Position was close to center for a factor of 1 (or 0dB amplification).
After swapping the 1k to a trim pot I was able to adjust 0dB to pot position centered spot-on.Great!

Thank you for your help again Joe,

Udo.


Thanks Udo great info :-)
Joe :-)

JLM Audio

Capturing Audio without Injury

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Joe Malone
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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Tue Aug 29, 2017 10:30 am

kante1603 wrote:
Joe Malone wrote:Set gain trim pot for +15 or +20dB gain
Add a resistor or trim pot in series with the pot wire going to 0v to limit the -dB amount to -15 or -20dB.

Wow,that was fast,thank you very much Joe!
Will try with a resistance decade to get some values later and report back.
In case of a series trim pot it is wired as rheostat,yes?
Seems I have buy some more dingo pup kits,hahaha......

Best regards,

Udo.


Cool :-)
Joe :-)

JLM Audio

Capturing Audio without Injury

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Fri Sep 08, 2017 5:29 am

Hi Joe,

quick question:My kits came with 6 x 100uf/50 lytics each,but they look like they are polarized (have minus-markings).
They have writings saying "NPR".Does that just mean "Non-Polarized Radial"?
If yes then I'm save to proceed.....

Best regards,

Udo.

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Joe Malone
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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Fri Sep 08, 2017 8:27 am

kante1603 wrote:Hi Joe,

quick question:My kits came with 6 x 100uf/50 lytics each,but they look like they are polarized (have minus-markings).
They have writings saying "NPR".Does that just mean "Non-Polarized Radial"?
If yes then I'm save to proceed.....

Best regards,

Udo.


Hi Udo Yes these are Non Polarised. So fine to use. For some reason that batch has a negative stripe on them which can be ignored.
Joe :-)

JLM Audio

Capturing Audio without Injury

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Mon Nov 06, 2017 2:31 am

Hi Joe,

hope you're fine.
A quick question:

Should the pcbs-when mounted using the pcb holes-better be isolated from chassis?
I just wonder because when measuring between the holes' metal rings and 0v on pcb I have the 10 Ohms as expected.
Which is the best way,using isolated or metal bolts/screws to chassis (which has a propper connection to mains earth)?

Thank you in advance,

Udo.

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Joe Malone
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Re: dINgO Pup kit BUILD THREAD

Postby Joe Malone » Mon Nov 06, 2017 11:17 am

kante1603 wrote:Hi Joe,

hope you're fine.
A quick question:

Should the pcbs-when mounted using the pcb holes-better be isolated from chassis?
I just wonder because when measuring between the holes' metal rings and 0v on pcb I have the 10 Ohms as expected.
Which is the best way,using isolated or metal bolts/screws to chassis (which has a propper connection to mains earth)?

Thank you in advance,

Udo.


HI Udo
The dingo 4 mounting holes are not connected to the 0v on the dingo pcb unless you fit the chassis/gnd link next to the input XLR. The 2 pads under the XLR positions are wired to the XLR chassis pins but this goes no where when no XLR's are fitted.

If using a floating 48v smps on plastic isolated DC connector with zeners fitted then 0v to chassis link fitted on the dingo pcb is a good idea and the mounting bolts will work to chassis.

If you have 10R between chassis and 0v I presume you are using a AC/DC or powerstation kit and no chassis to 0v link should be needed as the the 10R float will work fine.
Joe :-)

JLM Audio

Capturing Audio without Injury

kante1603
Posts: 85
Joined: Wed Jan 20, 2010 6:12 pm

Re: dINgO Pup kit BUILD THREAD

Postby kante1603 » Tue Nov 07, 2017 4:00 am

Joe Malone wrote:
HI Udo
The dingo 4 mounting holes are not connected to the 0v on the dingo pcb unless you fit the chassis/gnd link next to the input XLR. The 2 pads under the XLR positions are wired to the XLR chassis pins but this goes no where when no XLR's are fitted.

If using a floating 48v smps on plastic isolated DC connector with zeners fitted then 0v to chassis link fitted on the dingo pcb is a good idea and the mounting bolts will work to chassis.

If you have 10R between chassis and 0v I presume you are using a AC/DC or powerstation kit and no chassis to 0v link should be needed as the the 10R float will work fine.


Thank you Joe.

I'm doing a 500/51x module with the DingoPup serving as a kind of output trim function after my recording chains tp bring levels up or down going to my interfaces.There's also a high- and lowpass filter before the DingoPup.
Some kind of "tool" I need often when tracking.Normally I use an eq in shelf mode to have an adjustable highpass,and bringing up levels is done e.g. with a compressor makeup gain.
Overkill most of times when I do instrumental or classic stuff,here I only need a clean preamp,an adjustable filter and some output level control,not more.
That's why I had a few questions about having a pot or fader and how to modify to have a +/-15dB range etc.
Thanks again for explaining this so nice again!
I was just thinking about a "healthy" grounding concept because I have 3 grounds on my goldfingers (audio,psu and chassis),fed from a propper psu.All grounds meet at a star ground connection directy connected to the mains earth inside the psu and nowhere else,right "after the book".
Since all xlr pin 1s are connected to chassis ground in my rack by default I will start with the output stage (fader booster and balancer) going "earth-free" to avoid ground loops.
Will check this maybe next weekend.

Thanks again,

best regards,

Udo.

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