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The driveracks offer an option of "set" frequencies or "Live'. I always use the Live setting. It just sits and waits for an offending frequency and clamps it down. There are like 10 Frequency corrections available. It also has a timer. I set mine for 5-10 seconds. It clamps down then releases after the set time.

I've been using these for years on my monitors and we NEVER have feedback. So, check out the settings and see if it has those kinds of options - if it does use 'em. If you set 'em right, it will knock out the feedback, but not mess up the performance EQ.

Bruce Weldy wrote: ↑Tue Aug 18, 2020 6:05 pm The driveracks offer an option of "set" frequencies or "Live'. I always use the Live setting. It just sits and waits for an offending frequency and clamps it down. There are like 10 Frequency corrections available. It also has a timer. I set mine for 5-10 seconds. It clamps down then releases after the set time.

I've been using these for years on my monitors and we NEVER have feedback. So, check out the settings and see if it has those kinds of options - if it does use 'em. If you set 'em right, it will knock out the feedback, but not mess up the performance EQ.

Not sure the DEQ2496 has a timed release feature. I think it holds it, and has 10 bands available too, once all the bands are in use and a new offender arises it releases the oldest (first discovered) frequency and applies the new one. I think. The other features, Set and Live, sound similar to Behringers "Auto" and "SNGL" (single shot) features, where the SNGL identifies and holds the correction and wont change the frequency of the attenuation and wont ever auto reset to another frequency, but will continue to adjust the amount of attenuation and bandwidth (Q) of that correction.

You guys are getting me excited. Really looking forward to a no feedback show!

Too bad if it doesn't have a release feature......because most of the time is an odd situation that gets you. If it's happening on the frequency all the time, then that just needs some EQ to fix.....you hate to have it pull that frequency out for the rest of the night. But, it's still better than squealing!

Tonight was a little frustrating. Had a little trouble getting sound out of the mixer. Long story short, after changing out cables, switching outputs, and checking I/O settings on each piece of equipment several times over... the solution was a shut down and restart of the mixer (MIDAS M32C) and the stage box.

Then I wasn't able to get the Feedback Destroyer to destroy feedback. If I wasn't already bald, I would be now. LOL I decided to call it a night, do a little research back home, and found a wonderful post on the subject right here on billfitzmaurice.info of all places!

Problem understanding DEQ feedback destroyer settings

Back at it again tomorrow for some success to refill the bellows of my deflated enthusiasm.

So... no love yesterday. I'm a little puzzled and think I may have a gremlin. Maybe some of you have some insight...

A couple of months ago one of my amps (Ashly ne800pe) started up in protect mode (which is normal) and stayed in protect mode. Wouldn't come out of it, even with all inputs and outputs disconnected. It's a secondhand amp, so I figured it had just run it's course and gave up the ghost. I have another one, so I swapped it in. It did the same thing. In the moment I thought, what luck!!! two of the same amp model gone out at the same time. They both worked flawlessly the last time I used them. I stopped there that day, didn't swap in any more amps, and just back shelved what I was doing with them.

Fast forward to yesterday... I was having issues with the mixer again. It was just acting funny. Channel one was putting signal through, no matter what attenuation level. Even with every input and output muted. I cycled the power to the units several times and completely initialized all the settings in the mixer to no avail. It just isn't working correctly. While trying to troubleshoot that issue, the amp I was using (Behringer NU4-6000) went into protect mode and wont come out of it, even with all inputs and outputs disconnected. Plugged in another amp (Ashly 1800), power only... Protect mode too.

Now I'm thinking there must be an issue with the wall power. Checked at the plug and got 119.4v, checked at power strip that the amps are plugged into... 116.8v. Doesn't surprise me, the power goes through a few $2 budget power strips by the time it get's to that point. Although, 116v isn't really low enough to cause issues like this. Called it a day at the storage unit and came home to think it all over.

Seems awfully weird to have 4 amps in protect mode, with nothing connected to them but power. Plus a mixer that wont mix. Have any of you had any experience with this? The only thing I can think of, is maybe there's some DC power getting on the AC line from somewhere, causing the amps to go into protect mode. I'm gonna try unplugging everything in the storage unit and plug an amp directly into the wall next time I go to see if that changes anything. But, if you guys have any insight, I'm all ears.

I've never tried measuring DC on an AC line. Can I just put the Multimeter in DCV and probe the socket as usual?

It's possible that the circuit is wired incorrectly. It will still show voltage, but could be cross-wired. Maybe the amps see that.....don't know - just a thought. Take 'em home and try.

Use one of these to check it out....

Mmm for each amp model just for future issues, I’d research what causes protect mode.
I’ve have one amp, a yorkville, it turns out it stays in protect with no load, plus some other situations.
That’s a bit aside though when they did work, and now won’t.

Still, all in all, seems to me power is funky at the storage unit.
Take an amp, and the mixer, home to test with a different power source...

I'm fairly certain it's wired correctly. I get voltage between hot and neutral, and also between hot and ground, nothing between neutral and ground. So, hot is hot at least.



Thing is, I've used the amps in there for a few years now without issue. Still scratching my head on this one.

I did bring one of the Ashly amps home and it's still in protect mode. Had a chat with Jim over at Ashly and he said it's probably a hardware failure, $125 + shipping to fix. Not too bad until I consider I only paid about $100 for the amp in the first place.

I think I'll go grab the Behringer and bring it back home for a test. See if anything changes with that one. I'll test the line frequency while I'm there.

Also, I did a little research on testing for DC on an AC line and apparently it's done through a 100kOhm resister in series with a 1uF Non polarized Capacitor on the hot side. Not sure I'll get around to that this week. I am curious about it though. Wanna know why all my gear is going haywire! This could get expensive. I really hope the mixer isn't in need of repair now too.

It's really hard to believe that all the amps would exhibit the same problem at the same time. Only time I've ever had an amp go into protect was when I had a fried diaphragm in one of my NSD2005 drivers several years ago......it did just what it was supposed to. Unplugged the offending driver and everything was fine.

Bruce Weldy wrote: ↑Thu Aug 20, 2020 3:34 pm It's really hard to believe that all the amps would exhibit the same problem at the same time. Only time I've ever had an amp go into protect was when I had a fried diaphragm in one of my NSD2005 drivers several years ago......it did just what it was supposed to. Unplugged the offending driver and everything was fine.

I've had the same experience with an amp going into protect mode from a short in a speaker wire. I'm in the same disbelief. It was actually 2 separate times. Two went wonky a couple months ago and now 2 more. The Behringer was working fine on Tuesday evening when I first played with the Feedback Destroyer. Then, after being on and working yesterday for about an hour, it just clicked off and all the lights went red. The two that went a couple months ago, I was using an 1/8th inch to XLR adapter between my phone and the input for a source. The Behringer was sourced from mixer (also wonky)>DEQ2496>DCX2496>amp. The EQ and crossover seem to be working fine.

Just plugged the Behringer in here at the house and no love. Still going into protect. Comes on for a half a second or so, the fans start, and it clicks off to red lights.

I also tested the power frequency at the storage unit, 59.97Hz... so that's good.

WTF LOL Can't wait to figure this out.

Is it possible that someone's been playing with the wiring at the storage?
If active and neutral have been swapped on the main feed, you'll still get voltage (Depends on the DMM, but you'd also get a - in front of the voltage, but that's easy to miss).
But the gear won't like it at all...

Grant Bunter wrote: ↑Thu Aug 20, 2020 4:23 pm Is it possible that someone's been playing with the wiring at the storage?
If active and neutral have been swapped on the main feed, you'll still get voltage (Depends on the DMM, but you'd also get a - in front of the voltage, but that's easy to miss).
But the gear won't like it at all...

Anything is possible, people have been known to fiddle with electrical circuits in storage facilities. Although, I tested for a hot neutral swap. Seems to be wired correctly. There's no voltage between neutral and ground, but there is voltage between hot (active) and ground. (and obviously between hot and neutral)

Okies

Stretching my mind to figure this out... I wonder if one of the power switches in one of the cheapo power strips that are in line is dirty/corroded and arcing, causing noise on the line. No oscilloscope in my tool arsenal yet, so won't be able to rule it out. Suppose it's a possibility. None of them look out of sorts, no melty evidence of heat warping of the plastic or anything. They're all fairly new, purchased within the past 5 years or so. But they are all super budget deals.