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Strange sound when Pro 3 is turned on

Strange sound when Pro 3 is turned on
« on: February 12, 2021, 01:19:23 PM »
Like the title says, my Pro 3 makes an odd distorted sound if an amp or monitor is on and I turn it on. Iíve read there are known issues with powering on and leave everything off before turning anything on. My problem is if anything will happen to it like stop working at risk of sounding dumb.

I should probably contact support sorry I was just interested in if it was a known issue?

This is the first time a Sequential/Dave Smith instruments product has made anything more than a tiny crackle. The Pro 3 is really interesting to me, I had a Mono Evolver but I really donít know much about it, unimportant thank you for reading.

timborťale

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Re: Strange sound when Pro 3 is turned on
« Reply #1 on: February 12, 2021, 01:27:09 PM »
Very near the top of this topic there is already a thread about precisely this, called Pro 3 Sound Issues. You may want to check it out.
Rev2-16, Prophet 12 Keyboard, Nords, etc...

Re: Strange sound when Pro 3 is turned on
« Reply #2 on: February 12, 2021, 01:35:33 PM »
Thank you that was an interesting discussion and I did read it but it is a different issue it sounds fine to me. I cannot find the old thread I remember reading about this issue in sorry.

Technically itís not really any issue at all I just donít turn anything on before powering the pro 3 on. I just donít know if it could be a bigger issue.

Every time I turn the power on if an amp or something is on it makes a distorted sound, I just wait like 10 seconds and the display powers on, everything seems fine. Unless Iím understanding doing a power cycle wrong which I could be.

Found it! Some posters talk about this when powering on as well https://forum.sequential.com/index.php/topic,4204.0.html
« Last Edit: February 12, 2021, 02:40:28 PM by Username11 »

Re: Strange sound when Pro 3 is turned on
« Reply #3 on: February 12, 2021, 08:05:33 PM »
If you mean the pop, it still happens and support told me that's expected behavior. It happens on power off as well. The solution is to power on before speakers and off after speakers. But that's not always convenient and none of my other synths have this behavior. But I'm guessing it's a hardware limitation that won't be changed.

Re: Strange sound when Pro 3 is turned on
« Reply #4 on: February 13, 2021, 07:38:13 AM »
Yes that is what I mean. I think itís fine but Iím always worried something will happen to my pro 3. Just concerns me since nothing else works this way. Thank you.

timborťale

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Re: Strange sound when Pro 3 is turned on
« Reply #5 on: February 13, 2021, 07:52:02 AM »
I don't know exactly why this is happening on the Pro 3 but I can provide a little educated speculation on the typical reasons for loud pops and crackles on audio equipment during power transients.

Pops are usually what happen when an output buffer is DC-blocked (usually because the synth has no internal negative rail and uses a midpoint voltage as the "0" output voltage). Capacitors will initially let the adjustment from true 0V to this midpoint through (that's how they work physically, you cannot change it without physically changed the circuit design) and after they are charged to this baseline value only the audio signal is passed through. A lot of equipment makes loud pops when powering on, I have had a few mixers and effects units that do this, and an older Kurzweil keyboard I used to own was notorious for this, along with a Korg. So it's not at all uncommon for synths to make a pop and even some crackly noises immediately after powerup due to the analogue signal path and various capacitors at different stages charging up to their nominal bias voltages. When shutting down the reverse is true and they dip strongly negative for a quick second. If there's only a single transient you get one pop, if there are multiple (due to multiple analogue stages in the output amplifier, for instance) you can get crackles.

Why the Pro 3 does this and some of the other Sequential gear doesn't I don't know specifically - but this is the most common reason why and sometimes it's nigh unavoidable without introducing excessive output filtering that then has an audible effect on the sound, depending on the circuit topology chosen.
Rev2-16, Prophet 12 Keyboard, Nords, etc...

Re: Strange sound when Pro 3 is turned on
« Reply #6 on: February 13, 2021, 10:24:58 AM »
Wow thatís interesting and probably above my head but I think I understand, thatís helpful. I used to primarily play guitar with tube amps and solid state Iím used to pretty much silence except with some effects.  I mean you canít turn it on so.

I always noticed pops with keyboards and synthesizers this was just a lot louder. I did a power cycle and itís been making the noise on power off more often but I think that is random. It still makes an odd clipping sound before the display appears but I noticed itís not a big problem if the volume is reasonable.
« Last Edit: February 13, 2021, 10:35:31 AM by Username11 »