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Hardware Instruments => MiniBrute => MiniBrute Technical Questions - FAQ => Topic started by: GFC on October 10, 2012, 05:09:02 pm

Title: Audio in threshold
Post by: GFC on October 10, 2012, 05:09:02 pm
Is it possible in the next firmware update , to lower the thresholds by 10-20db or even the lowest setting by that amount as I find it very hard to trigger via audio gate without driving what ever i want to trigger it very hot.

Thanks

Title: Re: Audio in threshold
Post by: konspirativ on October 10, 2012, 08:41:22 pm
I second this request if possible! It's very difficult to trigger with any of the current settings, even with a drum machine or sampler hit at maximum volume.
Title: Re: Audio in threshold
Post by: Bruno@arturia on October 11, 2012, 09:26:58 am
unfortunately the thresholds level are not controlled by the firmware. It would need a hardware modification. A resistor value has to be changed.
Title: Re: Audio in threshold
Post by: Peter K on November 07, 2012, 07:29:44 am
It would be worth changing that resistor value in subsequent Minibrutes, and perhaps making a PDF available for current users to pass along to techs.  I ran other synths from the regular audio output with no luck, and had to start using the headphone out to get even close.  It would make parallel processing of synths much more feasible if the input level was more in keeping with what we've seen with other analog and digital signal processors. 
Title: Re: Audio in threshold
Post by: Bruno@arturia on November 07, 2012, 09:34:30 am
Quote
It would be worth changing that resistor value in subsequent Minibrutes, and perhaps making a PDF available for current users to pass along to techs.
Yes good idea, I don't know when, but I will for sure provide this PDF file.
Title: Re: Audio in threshold
Post by: leighmarble on February 09, 2014, 07:28:18 pm
Hi, digging up this old thread, but I'd be happy to start a new topic if anyone prefers...

Has a Technote been published for how to mod the Minibrute for a hotter audio input?

I was just trying the Audio In as a Gate Source again, with a drum machine as the source. Even with the drum machine's output volume at maximum, and the "Audio Gate Threshold" set to Low with the Minibrute Connection software, it still was not triggering at all. I had to patch in a preamp to add another 18dB of gain in order for the Gate to trigger, at which point the preamp's meters were indicating a +12dB output. That's pretty goddamn loud. A "low" threshold setting shouldn't require that much juice!

Thank you,
Leigh
Title: Re: Audio in threshold
Post by: megamarkd on January 27, 2017, 07:56:05 am
Apologies for the thread necromancy.
I have a drone synth I want to inject into the Minibrute but the MB is wanting a very hot signal.  As it stands I only hear the faintest of sound coming through when all the oscillators are at zero in the mixer.
I really want to make this happen, so I'm looking at getting a preamp to add enough gain to the signal, but if there is another way I'm open to suggestions.  If it is a job for a preamp, what is everyone using for that task?
Cheers.
Title: Re: Audio in threshold
Post by: leighmarble on January 27, 2017, 08:34:46 am
Apologies for the thread necromancy.
I have a drone synth I want to inject into the Minibrute but the MB is wanting a very hot signal.  As it stands I only hear the faintest of sound coming through when all the oscillators are at zero in the mixer.
I really want to make this happen, so I'm looking at getting a preamp to add enough gain to the signal, but if there is another way I'm open to suggestions.  If it is a job for a preamp, what is everyone using for that task?
Cheers.

If you just want to inject a drone, you could set the "Gate Source" switch to "Hold", and that will hold the gate open.

You also say "all the oscillators are at zero in the mixer". Gate open or not, you still need to turn up the "Audio In" slider of the mixer to hear the signal connected to the audio input.
Title: Re: Audio in threshold
Post by: megamarkd on January 28, 2017, 02:30:59 am
I don't want to create a drone, I want to use the drone I have like a bagpipe's drone; a constant pitch with notes played over the top.
Yes, I realise I need to turn up the Audio In on the mixer to hear anything.  It has been turned up to full when I've tried using the input.
I know a couple of people who own Minibrutes and their behaves the same.  Neither of them are using their Audio In's due to the low level of the input without a preamp of some sort.  I'm wonder what others are using to get a high enough gain so the Audio In is usable?
Title: Re: Audio in threshold
Post by: leighmarble on January 29, 2017, 12:53:45 am
I don't want to create a drone, I want to use the drone I have like a bagpipe's drone; a constant pitch with notes played over the top. Yes, I realise I need to turn up the Audio In on the mixer to hear anything.

Sorry, I misunderstood what you meant when you said "all the oscillators are at zero in the mixer".

The Minibrute only has one VCA – so you won't be able to have a constant drone PLUS notes that "stop and start" over the top. If you want that, then you'll have to mix your external drone oscillator with the Minibrute's output using an external mixer. In other words, the Minibrute's VCA is either held on (for the constant drone part), or it's turned on and off (for the "notes over the top" part), but it can't do both simultaneously.

I know a couple of people who own Minibrutes and their behaves the same.  Neither of them are using their Audio In's due to the low level of the input without a preamp of some sort.  I'm wonder what others are using to get a high enough gain so the Audio In is usable?

Ah – here, some of the confusion is revealed. This thread was originally about using the "Audio" setting of the "Gate Source" switch, i.e. triggering the Minibrute's envelopes using the audio input as the source. As I understand you, you are just trying to mix in an external oscillator through the "Audio In" fader – but you don't care about triggering the gate with it?

For external sound sources, being added to the Minibrute's mixer via the "Audio In" fader, I generally haven't had trouble getting enough level. One exception to that is there are a couple battery-powered drum machines I've input, and they are definitely on the quiet side. So in that case, some kind of boost is necessary. A preamp with a DI is one option. A guitar pedal (a boost or overdrive or anything with gain, clean or otherwise) would be another option.
Title: Re: Audio in threshold
Post by: megamarkd on January 29, 2017, 04:12:00 am
Ah – here, some of the confusion is revealed. This thread was originally about using the "Audio" setting of the "Gate Source" switch, i.e. triggering the Minibrute's envelopes using the audio input as the source. As I understand you, you are just trying to mix in an external oscillator through the "Audio In" fader – but you don't care about triggering the gate with it?

Yeah, I didn't want to start a new thread, found this to be the closest topic.....
Triggering using the audio signal would sorta work, but means no definition to the note.  I'm pretty sure a bagpipe player tongues the notes they play as there as a distinctive edge to each as they are played over the drone, so it's not a biggy not have the audio trig.

For external sound sources, being added to the Minibrute's mixer via the "Audio In" fader, I generally haven't had trouble getting enough level. One exception to that is there are a couple battery-powered drum machines I've input, and they are definitely on the quiet side. So in that case, some kind of boost is necessary. A preamp with a DI is one option. A guitar pedal (a boost or overdrive or anything with gain, clean or otherwise) would be another option.

That is exactly what I found.  I ended up jacking the Nandamonium directly in last night and it was more than sufficient.  That thing is dangerous to mixers if the "blast" button is pressed, but my original experiments with a Volca Beats and a PO Office were less than stellar.  I just assumed those machines would have a regular line level out, even though I was originally smashing both through a Monotron Delay before going into the mix.

Sorry, I misunderstood what you meant when you said "all the oscillators are at zero in the mixer".

The Minibrute only has one VCA – so you won't be able to have a constant drone PLUS notes that "stop and start" over the top. If you want that, then you'll have to mix your external drone oscillator with the Minibrute's output using an external mixer. In other words, the Minibrute's VCA is either held on (for the constant drone part), or it's turned on and off (for the "notes over the top" part), but it can't do both simultaneously.

What I did is set the env's to have longish releases so that the drone doesn't really drop away.  I still get some definition to the notes played with the drone note running in the background still.  I'm going to change the envelope retrigger mode also to hear how a legato envelope will affect it.