Bach On,
Microphone or Line level are an overlapping realm of output level (some condenser mics can put out +4 or more DBV with strong input), but from the description of the level you gave using your NU-3000 DSP with and without the Sampson level matching device, the output of your Artisian is closer to "microphone" level than "line".
At any rate, if your cabinet performs anything like the simulations state, you will need at least 10 dB of boost at 16 Hz for it to match the upper output level.
In terms of hearing "loudness", until you put in at least a +10dB low frequency boost, the upper harmonics will sound at least four times louder than the fundamental as is recorded in the sample.
Art
Any chance you have a copy of the samples in .wav files?
I Could be wrong but I though you had some access to them at some point.
It would be real easy to see what they look like with audacity.
Just load one and plot spectrum.
I have been working under the premise that the reason the pedals didn't sound as good as the stops in the manuals was due to the sound system. BUT, ISN'T IT ALSO POSSIBLE THAT PART OF THE REASON I HAVE NOT BEEN SATISFIED WITH THE SOUND OF THE PEDALS IS BECAUSE THE SAMPLES I'M USING ARE SIMPLY BAD SAMPLES?
Bach On.[/QUOTE]
I Could be wrong but I though you had some access to them at some point.
It would be real easy to see what they look like with audacity.
Just load one and plot spectrum.
I have been working under the premise that the reason the pedals didn't sound as good as the stops in the manuals was due to the sound system. BUT, ISN'T IT ALSO POSSIBLE THAT PART OF THE REASON I HAVE NOT BEEN SATISFIED WITH THE SOUND OF THE PEDALS IS BECAUSE THE SAMPLES I'M USING ARE SIMPLY BAD SAMPLES?
Bach On.[/QUOTE]
Art,
IF the input for the Samson box is rated at -10 and the output is rated at +4 db, isn't that a 14 db gain? So, if I can get some of that boost working at 16 hz, perhaps I can use the iNuke DSP to lower the intensity in the range where the higher notes are just a bit too loud.
But JAG is right. I need to find out what the samples really look and sound like. The measurements I have taken don't seem to be shedding much light on that.
Bach On
This is a FANTASTIC idea, can't believe I didn't think of it.
If you could upload one of the Artisan samples for us we can analyze it directly and you won't have to measure anything for this step.
(It would still be useful to measure the signal at the beginning and end of the signal chain to see what kind of low frequency roll off the components are cumulatively adding, but at this point in time that's not so important as analyzing the samples themselves to prove or disprove that they actually contain substantial 16 hz information.)
The DI box should be boosting the level of the whole passband, it can't be used as eq to boost 16 hz. I think you know that, but just making this clear. I think weltersys posted the DI box spec sheet which indicated it was capable of 19 db boost.
If your signal is strong enough you can use the Inuke dsp to boost the low frequencies OR cut the higher frequencies so they measure flat.
BUT if your signal is not strong enough you will want to boost the low frequencies, not cut the highs. The boost will lift the signal level while cutting lowers the signal level.
If you were able to measure the actual frequency response with a mic at several different locations in the audience then the high pass filter settings AND the low frequency boosting AND all other necessary eq could all be accomplished at once. You can't specifically boost 16 hz anyway (due to the Inuke's 20 hz setting limit) so this is going to have to be done with dsp tricks like shelfs and stuff. And it can all be done at once, protecting the driver AND getting flat eq'ed response. Otherwise you are going to have a WHOLE BUNCH of settings to input into the Inuke dsp, a couple of different shelfs, a high pass filter, a low pass filter, a few bands of parametric eq. This can be vastly simplified by doing everything at once.
This is much the same way that modern passive crossover design works. We no longer add discrete zobels and filters and processing (like notches and baffle step compensation) with separate circuits. We approach the whole thing from a holistic universal approach, using simpler and fewer circuits and parts to do the whole job at once rather than in individual steps with individual circuits and bucketloads of parts.
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The Sampson box has 19dB of gain according to the spec sheet I posted several pages back. You can use the iNuke DSP for boost or cut, but according to the cabinet simulation, the higher notes are a lot more than "just a bit too loud", they are 10 dB louder than 16 Hz.
At 1000 Hz, a 10 dB change sounds twice as loud, at 16 Hz, 5 dB sounds twice as loud. You do not need to do any measurement at all to know that the upper frequency range of any samples played will sound four times as loud as the 16 Hz fundamental, assuming the listener's hearing is within the average normal range.
You have all the tools required to balance the sound down to 16 Hz, just a matter of using them.
Give 'em a try.
Art
Guys,
I've been experimenting. And I have also been doing some measurements. Will post ASAP.
Is anyone familiar with this 18 inch woofer made by Stereo Integrity?
DS4 18″ Subwoofer | Stereo Integrity
It looks like something that might match up reasonably well with our box with the SI HT18.
SI also offers this subwoofer. It would be a different approach.
HST12 12″ Subwoofer | Stereo Integrity
I think JAG also recommended this one, though the price is steeper.
HST18 18″ Subwoofer | Stereo Integrity
The DS4 18" comes closer to fitting in a price range I could afford.
Bach On
I've been experimenting. And I have also been doing some measurements. Will post ASAP.
Is anyone familiar with this 18 inch woofer made by Stereo Integrity?
DS4 18″ Subwoofer | Stereo Integrity
It looks like something that might match up reasonably well with our box with the SI HT18.
SI also offers this subwoofer. It would be a different approach.
HST12 12″ Subwoofer | Stereo Integrity
I think JAG also recommended this one, though the price is steeper.
HST18 18″ Subwoofer | Stereo Integrity
The DS4 18" comes closer to fitting in a price range I could afford.
Bach On
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Hi Bach On,
The problem is not the drivers, it's the insufficient volume of the enclosures v. the desired low end corner frequency.
Hope you'll find time to post your measurements.
Regards,
The problem is not the drivers, it's the insufficient volume of the enclosures v. the desired low end corner frequency.
Hope you'll find time to post your measurements.
Regards,
Nobody is familiar with the new SI driver yet. SI just took delivery of their first production run somewhere around early this week and the first customers started receiving their orders 3 or 4 days ago. There's not more than a couple of people that have actually put these things in a box yet and powered them up.
I never recommended anything from SI except the now discontinued HT 18, as it was the value leader for the whole industry for awhile. The higher priced stuff isn't necessarily focused so much on value.
Like I said, if you keep an eye on the avs "for sale" forum you might find more HT 18s popping up for sale as the new driver rolls out and people upgrade.
BUT I'm going to once again recommend that you take things slow. I'd like to see frequency response measurements in the audience and know you are able to clip your amp signal before you start making more purchasing decisions. It's not like a used HT 18 is going to break the bank but still ...
I think everyone is really curious to see what you actually have there wrt measurements at the audience position and the signal strength issue and the power/breaker issue.
I'm still working on all my assignments for making various measurements. I haven't been bringing my laptop home. I'll upload the data when I'm done. I've also been adding the new preamps and checking out the church electrical system. I've also been trying to do a better job of labeling the various cables on the sound system. It looks too much like a packrat's nest. So far, I'm detecting no noticeable hum or other noise. I don't think I'll need any isolation transformers.
On another note (ahem), the used Allen B40 bass speaker I bought arrived this morning. It is actually a bit larger than I expected. Based on my measurements, it appears that it has an internal volume of roughly 11.4 cubic feet (35"x27"x21"). Add 1.5 inches to each of those to get the exterior measurements. It has a wire mesh grill that seems loose. I'll be removing that grill since I'm pretty certain it will be a source of unwanted rattles. I still have some nylon screening to provide minimal protection for the 15 inch driver. The unit weighs nearly a 100 pounds (98). So I'd need plenty of help to get it into the pipe chamber if I decide to use it.
I'm going to hook it up in the nursery to the Crown XLS1500 to see what it can do. I got the message loud and clear that almost nobody here believes it will add anything significant to our pedal line. But I'd already ordered it. My plan was to place it adjacent to the shades opening out to the Sanctuary. But we'll first see how it performs. I'm pretty sure I can sell it on the organ forum if it doesn't perform well. We'll just have to see.
Bach On
On another note (ahem), the used Allen B40 bass speaker I bought arrived this morning. It is actually a bit larger than I expected. Based on my measurements, it appears that it has an internal volume of roughly 11.4 cubic feet (35"x27"x21"). Add 1.5 inches to each of those to get the exterior measurements. It has a wire mesh grill that seems loose. I'll be removing that grill since I'm pretty certain it will be a source of unwanted rattles. I still have some nylon screening to provide minimal protection for the 15 inch driver. The unit weighs nearly a 100 pounds (98). So I'd need plenty of help to get it into the pipe chamber if I decide to use it.
I'm going to hook it up in the nursery to the Crown XLS1500 to see what it can do. I got the message loud and clear that almost nobody here believes it will add anything significant to our pedal line. But I'd already ordered it. My plan was to place it adjacent to the shades opening out to the Sanctuary. But we'll first see how it performs. I'm pretty sure I can sell it on the organ forum if it doesn't perform well. We'll just have to see.
Bach On
Parts Express sells round steel speaker grills - might need to also buy their clips for mounting the grills.
Don't impair the treble sounds with objects placed in front of the swell louvers.
Ben
Don't impair the treble sounds with objects placed in front of the swell louvers.
Ben
Ben,
The speaker and port will be about a foot to the side of the swell shades. I don't think it will impact on the treble.
I'll first see what it sounds like. Then the grill may or may not get attention.
But thanks.
BO
Well, I got that B40 going tonight. It really puts out some sound. I don't think it is as boomy as the homemade boxes. BUT - it cannot quite go down to 16 hz. I'd say it is pretty flat down to about 20 or 24 hz. Then the bottom falls way off. The low C (a nominal 16 Hz.) was a combination of a whisper on the fundamental note mixed with the overtones. I'd have to say it was more overtones.
But I think I'd like to try it in the mix and hear it with the homemade boxes. It do think it is a bit cleaner than my boxes from 25-64 hz. And there's not a hint of distortion or rattle. That metal grill was attached by some boards held in place with Velcro. I'll experiment with and without it.
Bach On
But I think I'd like to try it in the mix and hear it with the homemade boxes. It do think it is a bit cleaner than my boxes from 25-64 hz. And there's not a hint of distortion or rattle. That metal grill was attached by some boards held in place with Velcro. I'll experiment with and without it.
Bach On
Mic measurements can verify your gut guesstimate.
Stick a clothespin under the bottom pedal and record an RTA for a few seconds.
B.
Stick a clothespin under the bottom pedal and record an RTA for a few seconds.
B.
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Hi Bach On,
Hope you're making progress w/ the measurements.
Also, just out of curiosity, could you, please, provide additional dimensions of the Allen B-40, i.e.: wall thickness, depth of inset of the baffle board, diameter of the vent and length of the vent. An impedance curve of the B-40 would also be of interest. As a matter of fact, impedance curves for all the subwoofer boxes would be interesting.
Regards,
Hope you're making progress w/ the measurements.
Also, just out of curiosity, could you, please, provide additional dimensions of the Allen B-40, i.e.: wall thickness, depth of inset of the baffle board, diameter of the vent and length of the vent. An impedance curve of the B-40 would also be of interest. As a matter of fact, impedance curves for all the subwoofer boxes would be interesting.
Regards,
Oliver,
The internal dimensions of the B40 are:
22 Inches X 27 Inches X 32 Inches (the speaker panel is recessed. But I have taken that into consideration. This measurement is closer to 33 inches, but I went with a lower whole number. The wood panels are between 1/2 and 3/4 of an inch thick. I'd say 5/8 ths. It is some sort of hard wood - certainly not pine or plywood,
The port is four inches in diameter and 10 Inches long. Th
I have no idea what the specs are on the speaker.
Hope that helps.
Bach On
The internal dimensions of the B40 are:
22 Inches X 27 Inches X 32 Inches (the speaker panel is recessed. But I have taken that into consideration. This measurement is closer to 33 inches, but I went with a lower whole number. The wood panels are between 1/2 and 3/4 of an inch thick. I'd say 5/8 ths. It is some sort of hard wood - certainly not pine or plywood,
The port is four inches in diameter and 10 Inches long. Th
I have no idea what the specs are on the speaker.
Hope that helps.
Bach On
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Allen B40
Hi Bach On,
Thanks for the B40 dimensions. That's similar to your original home-made box, and would work well with the Dayton ST385-8. Attached, find a quick simulation. The port is too small; w/ the driver @ Xmax the port outlet velocity is 35m/sec. With the ST385 it takes only 68W (Eg=19.85V) to reach Xmax. The tuning should be right around 15Hz.
Regards,
Hi Bach On,
Thanks for the B40 dimensions. That's similar to your original home-made box, and would work well with the Dayton ST385-8. Attached, find a quick simulation. The port is too small; w/ the driver @ Xmax the port outlet velocity is 35m/sec. With the ST385 it takes only 68W (Eg=19.85V) to reach Xmax. The tuning should be right around 15Hz.
Regards,
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