Hello all, new member to the forums.
I am currently building my firsts DIY subwoofer. Sub will be sealed in a small 1-1.5 ft3 enclosure. Sub will be passive, with external amplification. I will decide on final enclosure size when I am better familiar with WinISD. I have a mini DSP HD which will be performed EQ.
In addition to the build, this will be my first foray into woodworking. I tried mocking up a box with the skill saw, and all my pieces were cut poorly. I have amassed scrap wood to practice cuts. Given my poor skills, I bought a cheap driver to fool around with. Until I am confident, I can build something decently.
Driver: https://hertz-audio.com/product/car-audio-subwoofers-uno-s300s4/
So right off the bat, in WinIsd, I made three of the same units all with a 1.5 ft3 box. The first is the box with no eq or filters. The system input power is ~200W. The driver can handle 250W RMS, but cone excursion hits the limit in this box size.
In the second unit, I applied a Linkwitz Transform. I did some reading. This is optimal for sealed boxes. I want to learn more about the LW Transform and have had difficulty finding literature online pertaining to its application in WinISD. The stock box is shown with the lower transfer function magnitude. Speaking of which, what parameters do I change in the LW transform? Or is it best to leave stock? Which is what I believe I did.
In the Third box, I applied parametric EQ with a 6DB boost at 30Hz. It looks slightly better than the stock box, but all of them look horrible compared to the LW transform.
Now for the part im having difficulty with when looking at cone excursion. The stock box handles 200W with no issues.
LW transform is okay until you hit 20Hz. Anything below will blow the driver. Input power has to be turned down to an abysmal 5W.
Parametric EQ with 6Db boost. Wattage has to be lowered to 50W. I am guessing because this driver has only a tiny 250RMS handling and a small X-max of 9MM. Is there not much room for improvement?
I am completely lost on the SPL plot. I can see the boost at 30hz on the Parametric eq, and the LW transform plot is the flattest of the bunch. However, The stock box still has the loudest SPL at all frequencies above 20Hz. Looking back at the first chart (Transfer function magnitude). How do I go about interpreting The best DSP for my box? I have yet to fool around with high-pass filters. I would need some insight into best practices. Or where I can find resources.
I am new to audio.
Apologies in advance if this was posted in the wrong forum. I wasn't sure if this was more of a subwoofer post or a SOFTWARE post.
I am currently building my firsts DIY subwoofer. Sub will be sealed in a small 1-1.5 ft3 enclosure. Sub will be passive, with external amplification. I will decide on final enclosure size when I am better familiar with WinISD. I have a mini DSP HD which will be performed EQ.
In addition to the build, this will be my first foray into woodworking. I tried mocking up a box with the skill saw, and all my pieces were cut poorly. I have amassed scrap wood to practice cuts. Given my poor skills, I bought a cheap driver to fool around with. Until I am confident, I can build something decently.
Driver: https://hertz-audio.com/product/car-audio-subwoofers-uno-s300s4/
So right off the bat, in WinIsd, I made three of the same units all with a 1.5 ft3 box. The first is the box with no eq or filters. The system input power is ~200W. The driver can handle 250W RMS, but cone excursion hits the limit in this box size.
In the second unit, I applied a Linkwitz Transform. I did some reading. This is optimal for sealed boxes. I want to learn more about the LW Transform and have had difficulty finding literature online pertaining to its application in WinISD. The stock box is shown with the lower transfer function magnitude. Speaking of which, what parameters do I change in the LW transform? Or is it best to leave stock? Which is what I believe I did.
In the Third box, I applied parametric EQ with a 6DB boost at 30Hz. It looks slightly better than the stock box, but all of them look horrible compared to the LW transform.
Now for the part im having difficulty with when looking at cone excursion. The stock box handles 200W with no issues.
LW transform is okay until you hit 20Hz. Anything below will blow the driver. Input power has to be turned down to an abysmal 5W.
Parametric EQ with 6Db boost. Wattage has to be lowered to 50W. I am guessing because this driver has only a tiny 250RMS handling and a small X-max of 9MM. Is there not much room for improvement?
I am completely lost on the SPL plot. I can see the boost at 30hz on the Parametric eq, and the LW transform plot is the flattest of the bunch. However, The stock box still has the loudest SPL at all frequencies above 20Hz. Looking back at the first chart (Transfer function magnitude). How do I go about interpreting The best DSP for my box? I have yet to fool around with high-pass filters. I would need some insight into best practices. Or where I can find resources.
I am new to audio.
Apologies in advance if this was posted in the wrong forum. I wasn't sure if this was more of a subwoofer post or a SOFTWARE post.
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Hello,
WinISD is a nice Software, but I think using Hornresp software might be easier to find support.
Below you can find the link to Hornresp and also CAD integration with it. I quite using WinISD when I found Hornresp 6 years ago. You have more design option to evaluate and it's simple to use.
https://freeloudspeakerplan.rf.gd/
It's not the help you asked but may give you a different option.
WinISD is a nice Software, but I think using Hornresp software might be easier to find support.
Below you can find the link to Hornresp and also CAD integration with it. I quite using WinISD when I found Hornresp 6 years ago. You have more design option to evaluate and it's simple to use.
https://freeloudspeakerplan.rf.gd/
It's not the help you asked but may give you a different option.
Hi, and welcome.
A couple of thoughts, in no particular order...
1: A Linkwitz Transform should result in a frequency response that's flat to just above its target frequency, whereas your 1st graph shows you still have a humped response (ie it's above zero dB). WinISD glitches when setting up the LT, so what you need to do is manually check that the F0 & Q0 values are in the left hand part of the LT dialogue box in the filters section are the same as the Fsc & Qtc values form the main Box screen.
2: Have a read up on a phenomenon called "room gain". The very short version is that in enclosed spaces the bass can build up beyond what is shown in basic models such as WinISD. That means that you may be better not to try and get your model flat all the way to 20Hz as that could result in over exaggerated bass once the project is operating in a real living space.
3: Most of the rest of what you're working out is absolutely correct - any filter that boosts the level will use up power and excursion, thus lowering your maximum available SPL. These are some of the tradeoffs that all designers come up against. However, what you're seeing is WinISD's calculation of what would happen if your full input power were applied at each and every frequency. Most real world program material doesn't have full power at frequencies below 20Hz, so you may be able to get away with a model that shows some overshoot.
Good Luck!
WinISD works fine here.
HighFutility,
The part you're missing is this: for every +3dB of EQ-based boost (NB - parametric, Linkwitz Transform, etc etc are all forms of EQ), you're applying 2x the power at that frequency. +6dB is 4x, and +10dB is 10x power. There should be options on the drop-down menu for Amplifier Power and Filter Gain. Check those out.
So, when you're on WinISD and apply +6dB of boost, you're telling the amplifier to put in 1000w instead of 250w. That's why cone excursion starts to get out of control.
You're starting where I started, more or less. I used 2x 8" drivers in a sealed box. I experimented for a while and wish I'd done the following sooner:
- Buy some measurement gear.
One of my best audio-related purchases was a half-decent set of measurement gear. A Behringer UMC202HD, measurement mic, a few cables, 100ohm resistor and a cheap laptop running Windows (for REW, XSim) will be incredibly useful for you. I wish I'd bought mine sooner.
Chris
PS - Revisit your Linkwitz Transform settings.
HighFutility,
The part you're missing is this: for every +3dB of EQ-based boost (NB - parametric, Linkwitz Transform, etc etc are all forms of EQ), you're applying 2x the power at that frequency. +6dB is 4x, and +10dB is 10x power. There should be options on the drop-down menu for Amplifier Power and Filter Gain. Check those out.
So, when you're on WinISD and apply +6dB of boost, you're telling the amplifier to put in 1000w instead of 250w. That's why cone excursion starts to get out of control.
You're starting where I started, more or less. I used 2x 8" drivers in a sealed box. I experimented for a while and wish I'd done the following sooner:
- Buy some measurement gear.
One of my best audio-related purchases was a half-decent set of measurement gear. A Behringer UMC202HD, measurement mic, a few cables, 100ohm resistor and a cheap laptop running Windows (for REW, XSim) will be incredibly useful for you. I wish I'd bought mine sooner.
Chris
PS - Revisit your Linkwitz Transform settings.