Limiter issues

[escapemcp]

I bought a proper DMM the other day and so wanted to re-check my limiter settings. It appears that I was running about a dB too cold on both subs and Otops

I set the limiter with a test tone, as per the plans. Then I began to test by trying my hardest to get past the limiter. All was well until I started playing with sweeps. I had the volume up into the red so it was making full use of the limiter. At low frequencies all was well... It never exceeded the 35V as per the plans. Once it started to get up in to the top octave though, my readout jumped to as high as 65V! Is this normal as a result of the higher frequencies and the dmm just not being able to sample often enough? (A guess, as I am not 100% how they work). Is it due to something else or should I be worried? When it did get up to these higher frequencies, I looped the sweep and my amp's fans started to go some. (Behringer iNuke NU3000DSP which is being used for the limiting).

I will try using the limiter on the deq tonight and see if I get the same result, or is this just normal behaviour... The fact that the fans started giving it loads suggests that this isn't a measurement issue.

Any thoughts or suggestions gratefully received.

Thanks

Aidan

[escapemcp]

As the issue is in the top octave, I am guessing that it isn't a big issue in terms of speaker damage as my piezos can take 35V, so my 2 banks of 7 (yeah, I chopped them to thin!) can take 70V... It's a bit close, but unlikely ever to see anything like this with music playback. It is just that I thought a limiter was supposed to be exactly that, yet in the HF, mine isn't!

I will also try seeing the limiters much lower and see if I get the same result... I can have the speakers attached at lower levels without pissing off the neighbours (too much). I can then see if the HF goes up in SPLs.

[byacey]

It appears that I was running about a dB too cold on both subs and Otops

I had the volume up into the red so it was making full use of the limiter.

One dB isn't much to fuss over. Consider it a margin for error.


If the volume was "in the red", there's a good chance you were clipping one of the gain stages causing the RMS value to go up. Most likely this is what you were measuring.

[DJPhatman]

Limiting is mandatory on horn loaded subs like ours, as the horn path naturally filters out distortion. For the mid-high tops, they will audibly complain if you are pushing them too hard, especially piezos. You may limit them, but if you are running them up to their limits often, you need more cabs.

[byacey]

As the measurement error seems to appear in the higher frequency band, it could be you're beyond the measurement bandwidth of the meter. depending what meter you have, it may only be accurate up to a couple hundred Hz.

[sine143]

or the behringer just might not push its weight down low, hard to say though.

[netwerks]

or the behringer just might not push its weight down low, hard to say though.

I wonder about this... if it's a product of poor power/line sag

[escapemcp]

If the volume was "in the red", there's a good chance you were clipping one of the gain stages causing the RMS value to go up. Most likely this is what you were measuring.

The volume was in the red, but NOT red-lining. Every bit of kit that I have has clipping indicators and none were lit. It was running hot but not boiling over

EDIT: just realised that as I am running digital out of my mixer, which does not have a level and clip meter, the issue could be there. Will run XLR analogue tonight to test.

[escapemcp]

As the measurement error seems to appear in the higher frequency band, it could be you're beyond the measurement bandwidth of the meter. depending what meter you have, it may only be accurate up to a couple hundred Hz.

I do have an old 'analogue' meter (with a needle)... Would this not suffer from this issue as it would be caps and the like, rather than some digital jiggery-pokery inside??? It's something else to test tonight, which is good.... I was looking for ideas and you guys are coming up trumps (as always)

[escapemcp]

or the behringer just might not push its weight down low, hard to say though.

Don't think so.. On the PC interface you can pick the voltage limit, and it seems to be very accurate. 65V is a LONG way past a 35V limit. It pushes out exactly what it should down low... So if anything it pushes above it's weight up high!!

[escapemcp]

or the behringer just might not push its weight down low, hard to say though.

I wonder about this... if it's a product of poor power/line sag

Don't think so... I have a 5-way plug with a voltage meter built in. Will check tonight, but our power is pretty good round here... 235V whenever I check it, day or night.

Many thanks y'all. ... Will check and report back.