Moderator: 3ne2nr Mods
I was reading up on motors, and this sounds similar to how they need a capacitor to get them to Start. It charges and discharges with the coil in the magnetic field, but with a delay, in the pattern of a hysteria loop.Brian Steele wrote:nervewrecker wrote:passive radiator?
Nope. A passively-assisted sealed alignment is basically a sealed design with a large capacitor in series with the woofer. Choose the value of the capacitor right, and you can end up with a nice boost at low frequencies. It can also help to reduce the "boom" of a high-Q box (which is what can happen if you shoe-horn a driver into a small box). The disadvantage is a bit of loss in efficiency (not peak SPL output - that's set by Xmax), but power is cheap these days.
You can read more about the technique at the link below, where I provided a worked example (and I might actually end up building that example for a project that I'm considering at the moment).
https://www.diyaudio.com/forums/subwoof ... ments.html
OffshoreMarketing wrote:kavaninho wrote:OffshoreMarketing wrote:Passive radiators around forever have them on my Polk audio systems from the 80s
check out the soundfire Sm-8 sub available at jdm master it’s a shallow mount 8” 300 rms nice output and response
Anybody in here uses soundfire, I'll like to know where they stand? Never heard a soundfire sub myself but this seems to be some mass alibaba buy that was brought in locally.
I Use them all the time seeing that i am the dealer “mass alibaba buy “ seems to be the talk going around.
I will say this much they are built by the same factories that build for plenty of the “best” brands ppl praise here.
kavaninho wrote:OffshoreMarketing wrote:kavaninho wrote:OffshoreMarketing wrote:Passive radiators around forever have them on my Polk audio systems from the 80s
check out the soundfire Sm-8 sub available at jdm master it’s a shallow mount 8” 300 rms nice output and response
Anybody in here uses soundfire, I'll like to know where they stand? Never heard a soundfire sub myself but this seems to be some mass alibaba buy that was brought in locally.
I Use them all the time seeing that i am the dealer “mass alibaba buy “ seems to be the talk going around.
I will say this much they are built by the same factories that build for plenty of the “best” brands ppl praise here.
I'm well aware of what is the trend.
I can call about at least 5 brands (but choose not to list here) that people glorify locally that are direct purchases from those Chinese build houses. Consumers must keep in mind they are purchasing a product that has little to no technical support from the vendor. That being said, some of the products are capable of actually doing well. I'm not bashing the Chinese manufacturing here as they just provide a solution based on their customer request.
Seeing "Engineered in the USA, Made in China" on a packaging would seem to be a lie as well.
I have no problem if someone decides to take up a business venture and distribute their "own" equipment brand. However, if the intent is to ship the cheapest thing available in the name of "my speaker is $100 less boidanboi", this will cripple the industry as the stuff will only get more inferior. Mind you, this would be the same industry that was once the said business owner's hobby.
I hope Local car audio don't get into that downward spiral. But I'm beginning to think its too late.
Brian Steele wrote:Building them in China isn't an issue.
Quality control is the issue. Like when someone orders a subwoofer driver of specs A, the manufacturer sends a sample that matches the specs, and then when the buyer orders in quantity, what is received are subwoofer drivers that look like the sample but are entirely off-spec.
To avoid this, the buyer should test random samples of the received drivers to see if they're within spec (short break in period and then measured by DATS or a similar tool), and the contract should be written to ensure a refund (or no payment) for any received drivers that are out of spec.
Drivers from the following sources always seem to be close to or meet published specs in my experience:
Infinity
JBL
Eminence (or any company with Eminence as the OEM for their drivers)
Alpine (except for one instance re rated power handling)
Parts Express (with a few exceptions)
It would be very nice if every driver came with a "birth sheet", similar to what's provided with many car audio amplifiers .
kavaninho wrote:^I'm not sure if you inputted the TS correct there. I had the 12TW3 in my WinISD database and the plot is no where as misaligned in your screen shot. Verify the TS against the manual.
Sure there are other plots to looks at, however, try to flatten those responses first.
kavaninho wrote:I did not even know people use point 3 above as an approach. I guess if you have capable DSP you can. IMO usually the more EQ and "DSP capability" you require after your system was built indicates poor decisions in the earlier stages whether it be driver selection or system design.
Return to “I.C.E. / Car Audio Tech”
Users browsing this forum: No registered users and 19 guests