Within the sub system, talking about feedback at 100 Hz, 36 degrees. That is only 1 millisecond. Is that a lot or a little time for a DSP to crunch the numbers?
To answer an earlier question: easy to blow up drivers when adjusting MFB since speakers are already having to perform outside their capable range (so weird behaviour is present). But with magic-appearing DSP processing, the feedback can be carefully configured to keep out of trouble albeit ONLY for the speaker under study... if you are lucky... and the weather doesn't change... and the driver doesn't age......
Ben
To answer an earlier question: easy to blow up drivers when adjusting MFB since speakers are already having to perform outside their capable range (so weird behaviour is present). But with magic-appearing DSP processing, the feedback can be carefully configured to keep out of trouble albeit ONLY for the speaker under study... if you are lucky... and the weather doesn't change... and the driver doesn't age......
Ben
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The servo amplifier is implemented in the digital domain rather than with analog circuits. This makes it easy to customize the servo without redesigning the hardware
The delay can't be eliminated but can be mitigated by using low group delay ADC's and DAC's as well as using small buffer sizes for the serial ports.
cheers
david
phase shift = latency * 2 * pi * frequency
most dsp boards use high latency dac's and adc's which is ok for audio streaming and multi channel audio because time delays of a few milliseconds won't be noticeable but is no good for a control system that has to process up to a few hundred Hz
cheers
It's hard to believe that the total latency is 10uS unless they are using single cycle flash converters for the ADC and R-2R ladder dacs and processing the audio at 96KHz with no buffering in the dsp. Perhaps they are using one of the AD Sigma DSP's with onboard DAC's and ADC's which has very low latency of about 40uS but still nowhere near 10uS !!
cheers
for a servo to be useful in this application it is wise to keep the latency below 100uS
1 or 2 mS in some DAC's is totally out of the question !!
Nice website. I look forward to your ground plane tests of the systems effectiveness.
Thanks. I often check your website for new reviews on drivers
I will probably do the acoustic testing when I have built the Titan-2 and have all of the electronics mounted in the box rather than in pieces.
BTW do you know of any 12 inch drivers with aluminium cones which preferably have an Xmax of at least 18 mm and a power rating of 500 watts or more. I am currently evaluating a car speaker but it only has an Xmax of 14 mm which is just on the margin of what I need.
cheers
david
Bozak in 1962 (maybe not exactly meeting all the requirements, sure sounded great at the time)
Ben
Check out the Ultimax series of drivers from Dayton Audio, sold in the US through Parts Express (not sure of Aussie distributor). Here is a link to the 12" driver:
Dayton Audio UM12-22 12" Ultimax DVC Subwoofer 2 ohms Per Coil
It doesn't have an aluminum cone, but rather a honeycomb construction that should make it pretty stiff. Xmax is 19mm. This might work very well for you.
Dayton Audio UM12-22 12" Ultimax DVC Subwoofer 2 ohms Per Coil
It doesn't have an aluminum cone, but rather a honeycomb construction that should make it pretty stiff. Xmax is 19mm. This might work very well for you.
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Hi, here's a couple of manufactures that produce metal coned drivers, for starters ! Not sure why you want metal cones though ?
Scan-Speak
SEAS: The Art Of Sound Perfection For eg D1001-04 L26ROY
Scan-Speak
SEAS: The Art Of Sound Perfection For eg D1001-04 L26ROY
Acoustic Elegance is supposed to come with an AV12/AV15 replacement very soon:
Acoustic Elegance • View topic - SBP15 to replace IB15A for car audio applications
Acoustic Elegance • View topic - SBP15 to replace IB15A for car audio applications
Yes I am aware of those drivers but they don't use metal diaphragms and you'd be surprised at how what appears to be stiff isn't at higher frequencies. I have an infinity car speaker driver with what appears to be a stiff driver made out of a composite fiberglass material. It feels like it is made out of concrete and yet it's first modal resonant frequency is almost half that of the aluminium coned driver !!
cheers
Yes I am aware of those and may have to get one into evaluate. Just a bit concerned about the stories I have heard how the diaphragms on some of the tcsounds woofers are easy to dent which means that the thickness of the aluminium maybe a bit light on.
cheers
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