Simulate with hornresp!
6th order parallel bandpass has more output and/or bandwidth than 4th order. But usually also more group delay.
My 6th order bandpass test box:
https://www.diyaudio.com/community/...-port-resonance-absorbers.388264/post-7434308
And a 8th order bandpass example:
https://www.diyaudio.com/community/threads/hornresp.119854/post-7365048
8th order bandpass has even more (theoretical) output, but multiple resonators and their losses may get a bit more unpredictable.
6th order parallel bandpass has more output and/or bandwidth than 4th order. But usually also more group delay.
My 6th order bandpass test box:
https://www.diyaudio.com/community/...-port-resonance-absorbers.388264/post-7434308
And a 8th order bandpass example:
https://www.diyaudio.com/community/threads/hornresp.119854/post-7365048
8th order bandpass has even more (theoretical) output, but multiple resonators and their losses may get a bit more unpredictable.
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I am following your work as you are already investing the same issues that I faced. Saves me from spending time on test box 1 and 2. Keen to see your discoveries. I am trying to address the problems of resonance and group delay along a yet unused lines, but I don't think anyone cares for it. Not always a bad, getting it pushed back on me allows to take total ownership of the results
When one has many deep interests and white whales in things other than audio.......... It looks like the "Firebird" an amphibious flats gokart also under development in my workshop just might be the catalyst to nail reflex systems
Thanks and regards
Randy
When one has many deep interests and white whales in things other than audio.......... It looks like the "Firebird" an amphibious flats gokart also under development in my workshop just might be the catalyst to nail reflex systems
Thanks and regards
Randy
Very cool, is that under 4L for total net driver volumes? What is the F3?Tiniest 40hz Sub...
Plus integrated subwoofer module :
T
Unibox will model a bandpass, and you have to use the PR section to convert to the PR volume from the ported in the model. If the PR is weighted, the smaller volume will be needed to raise the tuning. I would not use active and PR of same Sd dimension. You should be able to mount active driver through PR hole.
My Omega Ripole Micro is derived from the original Ripole principle subwoofer (as invented by Mr Axel Ridtahler) :
The F3 is circa 30Hz, and it works fine if you listen at moderate loudness levels. The sole issue is to find a correct mini sub module, and the one I used was not : the integrated LP Xover had a poor slope and frequency adjustment.
T
Thanks for sharing that, interesting design. I wish I could make smaller units with the Tang Band flat subs, but PE are the only outlet and not only out of stock but the shipping has been priced out of reach of AU builders. Which drivers are you running?
Wagner carry most of the Dayton's and SBA and wish they take up dealership for Tang Band too
I have been using OEMs in PRC for my non audio projects for a very long time. I am more exposed to brands, buying from Alibaba and getting their badges and custom colours put on generic designs from Ali than my peers and have come to a new realisation recently when perusing the Digikey and Wagner cattle dogs. I won't name the brand, but Digikey looks to be carrying many Ali drivers. From what I can see, a "brand" has made an inventory of a bunch of Ali drivers, and all signs are there that it's not a case of Ali reverse engineering IP but rather someone choosing from a PRC driver maker and not even bothering to change packaging or part numbers and such. You can get the same item from Ali in the exact same packaging or from yet another "brand" in an overseas speaker driver shop. Same item, in same packaging, same part numbers, same errors in the boxed literature at three different prices
I have been eyeing Tang Band look alikes on Ali, took a chance with a couple of units currently in post to see how they go against the branded units
Wagner carry most of the Dayton's and SBA and wish they take up dealership for Tang Band too
I have been using OEMs in PRC for my non audio projects for a very long time. I am more exposed to brands, buying from Alibaba and getting their badges and custom colours put on generic designs from Ali than my peers and have come to a new realisation recently when perusing the Digikey and Wagner cattle dogs. I won't name the brand, but Digikey looks to be carrying many Ali drivers. From what I can see, a "brand" has made an inventory of a bunch of Ali drivers, and all signs are there that it's not a case of Ali reverse engineering IP but rather someone choosing from a PRC driver maker and not even bothering to change packaging or part numbers and such. You can get the same item from Ali in the exact same packaging or from yet another "brand" in an overseas speaker driver shop. Same item, in same packaging, same part numbers, same errors in the boxed literature at three different prices
I have been eyeing Tang Band look alikes on Ali, took a chance with a couple of units currently in post to see how they go against the branded units
That would be nice if they are identified. Tang Band was VERY competably prized in the begining. I dont blame them for upping their margins as they`ve gained recognission, but give me unbraded TBs any day.
Cheers!
Cheers!
Nice, perseverance always wins. I have not come across this box layout, but it sure is interesting. With higher volume sound it may "walk around"a tad and some form of rubber feet may do the trick. Would love to see the final response curve from all around, as it may just be very close to a point source with those small dimensions. There should be no audible group delay as you cover less than one octave, nor any standing waves or even resonance. Fantastic little design in my humble opinion
My money is on the racer driver taking the tiny crown, This thing is built like an oval piston with massive travel. Pity there aren't any specs on this driver. Its a replacement for a brand name boombox's sub section
One thing I want to try with this one is a bandpass with a PR unit on each side instead of ports
One thing I want to try with this one is a bandpass with a PR unit on each side instead of ports
The driver’s resonant frequency (Fs) can be measured without any special tools.
First, break in the suspension by pushing the cone in and out by hand to around Xlim (as far as the suspension will allow) several times.
To measure Fs, connect the “+” output of a frequency generator/amplifier output directly to the driver “+”, place a ~10 ohm resistor in series with the driver “-“ . Connect an AC voltmeter across the resistor leads. Adjust the output level to around 4 volts for an 8 ohm driver, 2.83 for a 4 ohm driver, then sweep the frequency up and down until the voltage across the resistor reaches it’s minimum. The voltage minima is the resonant frequency.
Testing at a lower voltage level will probably result in a higher Fs until the suspension is fully broken in or "warmed up".
First, break in the suspension by pushing the cone in and out by hand to around Xlim (as far as the suspension will allow) several times.
To measure Fs, connect the “+” output of a frequency generator/amplifier output directly to the driver “+”, place a ~10 ohm resistor in series with the driver “-“ . Connect an AC voltmeter across the resistor leads. Adjust the output level to around 4 volts for an 8 ohm driver, 2.83 for a 4 ohm driver, then sweep the frequency up and down until the voltage across the resistor reaches it’s minimum. The voltage minima is the resonant frequency.
Testing at a lower voltage level will probably result in a higher Fs until the suspension is fully broken in or "warmed up".
When the distortion hits around 10% at the Fs (free air) the driver has hit Xmax.
You can easily see the peak to peak excursion, compare it to a ruler, divide by 2.
Using a sine wave, 10% distortion can be seen on an RTA (like REW has) as a harmonic reaching -20dB of the fundamental frequency. Better speakers have less distortion past the second harmonic (40,80, 120, 160 etc.).
Distortion usually increases from 10% to 100% without much additional voltage.
Be careful with the duration of the test, sine waves have far more average power than music.
You can easily see the peak to peak excursion, compare it to a ruler, divide by 2.
Using a sine wave, 10% distortion can be seen on an RTA (like REW has) as a harmonic reaching -20dB of the fundamental frequency. Better speakers have less distortion past the second harmonic (40,80, 120, 160 etc.).
Distortion usually increases from 10% to 100% without much additional voltage.
Be careful with the duration of the test, sine waves have far more average power than music.
Setting up for the passive radiator test for the ZR6.4D vs the racer. I am thinking a cube for the test box as it will have to take 6.5” PR units on each side and a driver on the face. Foam cubes can ballast the volume back to 4L
This is very much an active project but, being the primary carer of a new baby, has made it quite difficult to work in the wood cutting area in the carport. Jaggy is very demanding for constant attention, and I have been getting exhausted and taking afternoon naps. Looking forward to the sitting up and crawling around stage and independent play that comes with that
In this meantime, I think I could do with more automation to take some load off my time. Looking for a value CNC solution with at least half sheet work area. Then I can get the sheets cut in half at the hardware and machine a number of panel parts at a time. My CNC has standard extrusions, so the possibility to upgrade the work area with longer reach must be explored too
In this meantime, I think I could do with more automation to take some load off my time. Looking for a value CNC solution with at least half sheet work area. Then I can get the sheets cut in half at the hardware and machine a number of panel parts at a time. My CNC has standard extrusions, so the possibility to upgrade the work area with longer reach must be explored too
Hahah!
One child = one source of chaos
As long as that source is immobile, life is much easier. Two sources of chaos are manageable as long as you are able to see them both at the same time, three on the other hand...
My daughters are 13 and 11, so far it seems to me that the amount of work is constant, it is the form of work that changes. A journey in patience and learning, for all parties involved.
As long as they are small it is easier to get good hugs, each segment in upbringing has its own charms and challenges, enjoy each segment while it lasts.