You have to know someone fairly well before making the means by which you find humour. We are not there yet. I find your remarks to be in pretty poor form. Since you have established anonymous support for your brand of humour on this forum, I am unable to respond freely
When you fire up the dats and are highly disappointed by the ds18 parameters some of this might make sense (finally) …
It'd difficult to fathom the scale of push to stop me from proceeding with these drivers. I am not worried about them not working out so what I am doing must mean that it might affect anothers income or something? I also do have a decent enough small box solution already. If the drivers that I am looking at work out, they will be a plus
This is a DIY site, I will proceed
This is a DIY site, I will proceed
I am interested, can you please show me some such tests with this class of drivers before I risk damaging my drivers? When you do, I'll show you some vids of how much it takes to properly break in this class of drivers and how long it takes before they are
Let's call a spade a spade.....
It's been stated enough times already that the current mini-Dj rig is 4x commercially made and THX certified 7" gaming subwoofers that have proven to solidly reinforce the pair of 15" Samson two-ways in an outdoor porch as stage and lawn as audience setting plus a single standalone 2.1 portable frankened with one more of those gaming system
The intent is to better the output and lower the extension from the current solid performance at 40Hz
The only drivers that seemed to be designed to run well in the cab size range that I am after seem to be from the ZR and ZXI series from DS18
Cab size constraints is the dominant factor
You folks have seen me invest in decent amplification for the project as well as comprehensive DSP in form of the 2/8 DSP processor and Roland MX-1
Intuition says that I am well-prepared to tackle the project and meeting my targets is very feasible and you folks are saying not happening. Still sure?
It's been stated enough times already that the current mini-Dj rig is 4x commercially made and THX certified 7" gaming subwoofers that have proven to solidly reinforce the pair of 15" Samson two-ways in an outdoor porch as stage and lawn as audience setting plus a single standalone 2.1 portable frankened with one more of those gaming system
The intent is to better the output and lower the extension from the current solid performance at 40Hz
The only drivers that seemed to be designed to run well in the cab size range that I am after seem to be from the ZR and ZXI series from DS18
Cab size constraints is the dominant factor
You folks have seen me invest in decent amplification for the project as well as comprehensive DSP in form of the 2/8 DSP processor and Roland MX-1
Intuition says that I am well-prepared to tackle the project and meeting my targets is very feasible and you folks are saying not happening. Still sure?
The other thing is, starting with the original post, this thread is about an auditioning box based on a BR system. All my studies so far indicate that the port is a function of cone displacement and a TL is the way to go and one that can come back and bite itself is better. The driver displacing more down this tube will have a higher output that is cleaner than a poor aspect ratio port
The only parameters that matter for the physical box design is cone Sd and Xmax, in other words Vd
This port only system has problems though. At the 183cm2 suggested by BP1Fanatic, the output is highest, but delay along the upper sub band is high. This is independent of which driver. This is a length and Sd thing
The 130cm2 Sd with scoop exit that was my final tapped TL auditioning model hit the spot with the best tube performance in all the graphs. Plus it looks good
But it still leaves a question mark if a BR is possible. We have to remember that the BR port again at 1803cm2 is way too long for a 30L box and increases overall size out of the desired range. So a traditional port is not an option. It seems like I am the only one curious about how to solve this. I have a number of drivers from 6.5" to 12" from DS18 and others to try to find which is the best fit for the largest 4x boxes that I can carry and store
The only parameters that matter for the physical box design is cone Sd and Xmax, in other words Vd
This port only system has problems though. At the 183cm2 suggested by BP1Fanatic, the output is highest, but delay along the upper sub band is high. This is independent of which driver. This is a length and Sd thing
The 130cm2 Sd with scoop exit that was my final tapped TL auditioning model hit the spot with the best tube performance in all the graphs. Plus it looks good
But it still leaves a question mark if a BR is possible. We have to remember that the BR port again at 1803cm2 is way too long for a 30L box and increases overall size out of the desired range. So a traditional port is not an option. It seems like I am the only one curious about how to solve this. I have a number of drivers from 6.5" to 12" from DS18 and others to try to find which is the best fit for the largest 4x boxes that I can carry and store
Please do not bring the thread down with this bullying and trolling. I notice that you have support to continue with such, but I am telling that it is not welcome. I would appreciate it if a mod would clear the thread of your childish manners, but don't really see it happening since I am the one getting penalised for standing up to your bullying
How thick are you that you can't get the call to refrain from speaking down to me
Every time I try to make a clean attempt, someone like you just brings it down with. You can't help yourself, even when asked to refrain and get me penalised if I say anything stronger in return. If you don't like what I am doing and if your culture does not allow you to speak in civil manner then please stay clear
I'll make a new attempt and request that this time around please keep it technical and keep in mind the experimental nature of the work. The continued personal remarks and trolling needs to stop. As it is, you have brought this thread down to a point where I no longer wish to mix up any progress and results in the midst your trolling
Hey man, I can see you been curious. Did you ever look into how the car pro installers break this class of drivers in? The last new issue driver that I witnessed getting broken in, it took the installer a week of driving to full excursion to start measuring differently, and even then it was declared no where close to being properly broken in. I did not have the patience to leave it for another week, and did the rest of the way in the car. The transformation just happens when it happens
I would rather instead just head out for, 2000km return road trip and run it hard. The intent is to do so using a cab with the type of sound that I prefer and one that compliments the driver
You guys can dispute my stance that the port is a function of VD and not the cab all you want, but this is not going to stop me from trying to prepare an auditioning cab to where I am satisfied with it
I have prepared a 30Hz ported design to audition with and the TL version which Hornresp shows as better use of the components in the physical circuit. But I have an unresolved issue that is preventing an immediate start with the BR design. This as I already mentioned is about how to accommodate the HF drivers. The TL version below has the space for this, but I really want a BR for the initial box
These three need to go into the cab. Getting the racers in elegantly ina stereo pair is proving to be challenging. Thinking about more of wedge shape with coax sub coax. Wedge so that the coax have a chance to fire up. This position will also allow the trio to be split up if done right
Boogs, I have rigged it up for free air. Let's leave it for a day like that and get the suspension moving in the range that will be affected by the DATSv3 signal
Guys, it would be a refreshing change to work on this without the didgeridoo talk. Folks keep suggesting 180cm2 port Sd as minimum and making the assumption that I am ignoring good advice, so let's dissect this. Maybe I have a misconception that the following would be a poor port resonance performance
Here is the recommended widish port. I have increased Vb to the stock recommendation of 38L for ported and 32hz tune for the sim. So please explain why do you folks recommend this response over the clean and flat output graphs from the original post BR concept. In other words, and quoting and earlier such remark, why recommend the wheel over reinventing it? This response is with a 100Hz filter
That seems like a bit much for such small Vas, you can also tune a bit higher, to reduce the port length. That will reduce your unwanted outcome, while still giving good 30 Hz performance.
- Simulation programs often exaggerate peaks and dips of that kind. So the fact that you simulate it doesn't mean it's going to be there, or at least not with the same order of magnitude in real life.
- You're comparing a simulation in HR to a simulation in WinISD, two different programs that will give different results, for the same input parameters (where possible). My suggestion is to simulate both in HR.
- I would cross that driver a lot lower, say 80 Hz and 3 or 4th order. Again for a better outcome.
- I tried to input that driver into HR, I got a lot of inconsistencies in T/S-parameters, Re, Mmd/Mms and BL seemed weirdly off. I would await DAT's outcome.
- Like I hinted earlier, I've build so many subs of that kind, that your first post simulation seems way off without even simulating it. My experience with measuring those enclosures tells me that they mostly resemble a simulated rear loaded horn in HR, meaning Vtc, Atc, S1, S2 and L12. Use L3, L4 etc. to approximate the flare.
Thank you for a proper dialogue on this. Initially, I used the chambers (tried both rear and throat) but ran into issues simulating the fill needed fill. Its seems that pipe models offer more features
That is the anomaly. The 38L recommended by DS18 actually makes sense if I try to correct for the electrical anomaly but still a wild speculation on my part
When I saw the presentation on ports by DIY Audio Guy, realised that the 180cm2 recommended by guys here is the optimal for output but also that it was a function of Vd. So I messed with port with a driver volume and port with no driver volume (TL) in HR until I found a compromise at 130cm2 for 31.4Hz that eliminated most of the peaky dips. This appears to be controlled entirely by pipe length to diameter and taper rates
Can this be used to determine a box with only cone Sd and Xmax numbers in hand? I may not know acoustic engineering but proportioning a 3D object is within the skill set. Time is there to investigate this
Continuing on with the three drivers. Creating some GA's show, a minimum footprint of 580mm x 400mm and minimum height of 600mm needed to accommodate the trio. This is larger than what I desired but accepted as compromise
Anyway, the old system will get used for the 7th Aug. A 30Hz box without pipe resonance issues is not simple to assemble, which makes it difficult to achieve a result with trial and error
Randy,
You won't hear any real stereo effect from drivers mounted in a 580x400mm cabinet, other than room wall reflections.
The angle they sit at looks about right to even out the beamy tweeter response with a mono signal, but the co-ax drivers should be placed as near to each other as possible to reduce comb filtering.
Have you listened to how much noise the subwoofer's rear vents and spider make at 70mm peak to peak excursion?
Art
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Yes, some are good and some sound like jackhammers. This one seems ok in free air but giving it very lil plugged in place of the 7". Don't want to tax that amp
Working on it 🙂
580mm is accepted as compromise total width, made up of three units attached with magnets in the cab. 180mm width for the coax and 320mm for the sub without needing to reverse the driver. This way is max versatility as the coax cabs can be stacked on one end of the sub and stood up. So 2,1 bar, 2.1 split or mono with twin coax tower. Seems like the easier design to draw too over a common cab