Voicing in the 16 and 32 foot in the pedal

All…

In my organ room, I’ve noticed with some samples that certain stops in the pedals on certain samples seem to be verrrrry “boomy”. It seems to be mostly (but not only) the Bourdon 8 and lower and several others.

What is the best way to handle this? With a few 16 foot pedal stops in several samples (big acoustical ones like Nancy and Aristide) I have turned the volume down as low as it’ll go and the only way I can seem to get ride of the “boom” is to deselect the stops.

Any thoughts or ideas??

Thanks guys

Pat

I'd recommend turning down the sub. As others have said, less is more!

As said, turning down the sub could help. Also lowering the sub's low pass filter -- if it's reinforcing an 8' Bourdon, it's playing into the 60 Hz range and your speakers probably cover that octave already, so the sub shouldn't. I set my filter to 31 Hz and 12 dB per octave attenuation. That supports the top of the 32' octave and the bottom of the 16' octave, but is barely a murmer in the bottom of the 8' octave.

After trying that, if there are specific notes that boom a lot more than others, selectively decreasing those notes may be needed. The room can amplify certain pitches, across all stops that include that pitch as a strong fundamental.

Don't boost your subwoofer volume just to hear something throughout the bottom of the 32' octave. Most house rooms aren't long enough in any direction to allow a standing wave down near 32 Hz to form. There's a 32' sine wave in the Calibration organ by Al Morse: http://almorse.org/content_freeorgans.html

My 17.5 ft cube-shaped room only gets down to a 27 Hz wave. Below that note, A below 16' C, turning up the sub just rattles the house uselessly even though the sub's nominal range is 16 Hz. The driver can move at that frequency without being able to form a standing wave because the room's too small.

I think it is indeed more not specific…. For example, the low Db (D flat) and low F seems to be the two culprits of the scale. As I mentioned, I’ve turned the volume down all the way on a few of them and for some reason, to my ears it didn’t seem to help much at all which surprised me.

I’ll try to tweak it again and see what I can come up with…. My original guess as you guys have commented on is that its the room harmonics.

Thanks!!

Pat

[mdyde]

I’ve turned the volume down all the way on a few of them and for some reason, to my ears it didn’t seem to help much at all which surprised me.

In case it's relevant: if it's a surround sample set, make sure you adjust the note's voicing for all of the perspectives (or at least for the ones that are causing the problem.)

I repeat my statement, that‘s always a problem with room modes. When you use loudspeakers to play Hauptwerk, only the use of a DSP will bring a satisfactory result. When you eliminate the room modes with voicing and use headphones, the eliminated frequencies are not hearable with them when you don‘t implement a second HW instance.

It‘s very simple to detect room modes: divide 330 m/s (sound velocity) by your room dimensions.

If you have a room with 6 meters for example, divide 330/6=55 Hz. That‘s your lowest room mode. The DSP should lower the amplitude of this frequency.

I use miniDSP with Dirac-software (I don‘t work for them ). That‘s a rather simple method if you are willing to study the subject a little bit.

When you use multichannel sets then you can use Dirac(max 16 channels) or Sonarworks (max 10 channels). as software VST. Then you have to use Reaper as well.
Dirac is the best but when you use it then you must always be online for startup verification.
In fact you neutralize your room influences before Hauptwerk and every new sample set you install will sound good right out of the box.
You only need to voice to suite your taste.

Jan

Dirac is the best but when you use it then you must always be online for startup verification.

If you use a miniDSP, as I said, you can export the Dirac filters to the box and then use it without a PC. There are also other brands (like NAD) where you can use Dirac with an AV-receiver.

Hi Pat,

I think you're experiencing the effect of standing waves, ie, the problem notes have sound wave lengths the same length (or a multiple of) as some room dimension(s) and in effect that acts as an amplifier to them, a booming effect.

I experienced this problem some time ago when I first started playing my then-new piano/synth, a booming effect for notes just around the D two octaves below middle C. The wavelength is about 15', the length of my music room. I fixed that with a hardware equalizer that reduces the signal strength around that note.

I have the same issue with every sample set, some notes sounding louder than others around them because of the standing wave effect. It also is better/worse for certain kinds of stops. I fix those with just voicing changes for those specific notes/stops.

In addition to the good suggestions above, I suggest the following:

First, I found that the location of my subwoofer was critically important, and that moving it (not easy for a 100# plus unit) just a few feet made a big difference in the sound throughout my music room. For example, I would have Hauptwerk play a recording while I walked around the room, and I found spots, literally just a few feet apart, where the volume was very high versus others that were too quiet. Moving the sub made a difference.

Second, and I think very important at least in my case, was getting the volume of all of my speakers and sub balanced. I bought (from Radio Shack, so quite a time ago) a sound level meter, a simple meter that I set in the middle of the room to measure the decibel level of sound. I then played a pink noise signal through my audio system, one speaker at a time, and adjusted the volume level of each so all produced the same dB levels. Interestingly, the biggest change I had to make was in reducing the subwoofer level. Having done these settings by ear at first turned out not to be accurate at all, in part perhaps because I had several different kinds of speaker-pairs. I think this balancing helps make any subsequent voicing much easier for any sample set.

Others may have simpler and better explanations of this, but hopefully this is some help. The booming effect is completely annoying!

Barry

BarryG,

Could you explain what you mean by a 100# plus unit? Is it a signal processor of some kind?

The weight of the subwoofer is at least 100 lbs? I don't know what that is in stone...

Sorry, I realise that you must have been using 100# as an alternative way of writing 100 lb. I have come across Americans referring to what we in England call a hash as a pound sign, but I didn't realise that it was used as an abbreviation for pounds weight. I think you also use # instead of No. when referring to numbers. The abbreviation lb comes from the Latin word libra, which is a unit of weight approximately the same as a pound, so I would imagine that it has been used in England for centuries if not millenia.

In the UK there are 14 pounds in a stone, so 100 pounds is just over 7 stone. However, we mostly use metric units, so it would be just over 45 Kg. I think your pounds are the same weight as ours, even if your gallons are a lot smaller (and your quarts? We have four quarts = 8 pints in a gallon).

Coming back to the original question: I have much the same problem with resonances in my room. I have found that adjusting the crossover of the sub-woofer to avoid too much overlap with the other speakers is certainly helpful, but there are always some notes that require revoicing otherwise they sound much too loud and the windows start to rattle. They are usually always the same ones and it is 16' and 32' pedal flues (the manuals hardly ever seem to have that problem, possibly because 16' manual stops tend to be quieter than 16' pedals of the same family, or possibly becuase I don't use the notes at the bottom of the scale so much). Three pitfalls to avoid:

1. If one stop is an extension of another then you may find that only one of them allows revoicing. For instance a 16' pedal principal may be an extension of an 8' manual diapason.
2. Make sure that you are adjusting the correct octave (it isn't always obvious).
3. For surround and multiple perspective ranks you need to adjust all perspectives. I do this by selecting them together (using the CTRL key as per standard Windows, but I don't know how you do it with a Mac). Possibly you could get better results by adjusting each perspective separately, but I would rather spend my time playing than voicing).

For some reason I get a lot of artefacts when I play anything while the mouse cursor is over the voicing window, but it isn't enough to stop me doing the job.

Once I have adjusted a rank then going up and down the scale then there are no notes left that are much louder (or occasionally quieter) than their neighbours. The rank as a whole may have been voiced by the builder to get louder or quieter as it ascends, and I would try not to disturb anything like that as it is fundamental to the tonal concept of the instrument.

In addition to the above.
If you lower the volume off a bass note with a resonance peak with for instance 8 db to counteract the peak in your room then you also lower the harmonics of that note with 8db so changing the overall character of this voiced note.
If you perform a lot of voicing to counteract resonances then you wil change the character off the organ in the low end.
Counteracting room nodes with roomcorrection avoids this.
I my opinion voicing is not the correct tool to correct resonances

Jan

If you want to do it very well, you will have to make your room a dead space, as is done in radio studios. So use a lot of sound-absorbing material. For example, with empty egg cartons on the wall and carpet on the floor, the solution seems to me to be the solution. And don't mess with the sound of the organ.
Succes Coos.

Absorption needs to be very bulky to be effective at low frequencies. But having a well-furnished room (sofa's etc) may help quite a bit.

I agree that room correction / EQ software is the best tool for reducing boomy notes.

A quick & dirty solution in Hauptwerk is to decrease the amplitude of the samples that are problematic in your room, and increase the brightness of the samples by the same amount. But that only works if the boomy frequencies are not in the harmonics of the sample.