For subs, I tried a isobaric. I did better just using the second driver as a second sub. Low Q, sealed. Some will argue the advantages of two in push pull, but my ears have not noticed any advantage with high quality drivers.
I am not sure time delay per say is the issue, just trying to correct something that is past and is doing something different now than when you got the error signal. How fast can you make the servo respond and still be stable? How tightly coupled can the servo be to a very high mass and damped system? I have seen the math. It is not for me.
If you think a woofer should not sound natural then Servo is for you ...
Anyone building a subwoofer system and it cannot produce a proper bass note below 60 hz should be shot with do doo, Then again most believe 2 cu ft subwoofer enclosures work ...
Size , size ..........
One can hear a servo controlled subwoofer a mile a way , sonic signature abounds .......
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Not enuff isn't the issue Brad, its the artificial sonic signature from "error " correction , ok for Home theatre where there's no reference and most believe the slam of a car door should shake the house ...
If you think a woofer should not sound natural then Servo is for you ...
Anyone building a subwoofer system and it cannot produce a proper bass note below 60 hz should be shot with do doo, Then again most believe 2 cu ft subwoofer enclosures work ...
Size , size ..........
One can hear a servo controlled subwoofer a mile a way , sonic signature abounds .......
Have you measured subwoofers? I measured quite a few about 8 years ago. They all had real output limitations below 60 Hz and while they responded to 20 Hz they did not move much air.
The THX spec requires a high pass at 35 Hz.
How many servo controlled subwoofers have you heard? Which technologies? You are lumping them all in together.
You can control the loop around a system up to the frequency where the delay caused phase shift introduces positive feedback. There are very sophisticated systems for extending higher. I can control a digital loop (Noise cancelling headphone) up to about 3 KHz but the feedback is dialed down to unity around 3 KHz. The digital part is not the limit in this case. Analog systems have the same limits or worse.
All vinyl produced since about 1962 or so was done with a feedback cutting system. You really can't avoid the technology.
Yes measured quite a few a decade or so ago and listened to enuff servo controlled units to know it was not for me, the two sticking out in old memory is velodyne and genesis. The decay and output is artificial and unnatural sounding to me, it does not sound right , best for steady state operation , maybe they have gotten the PID values and operation better today , but that original sonic signature never left me , i can hear one a mile away ....
I can understand and agree fully with running cutters closed loop , repeatability and no overshoot is a necessity....
Regards
I can understand and agree fully with running cutters closed loop , repeatability and no overshoot is a necessity....
Regards
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The home theater sub was not servo controlled, merely had a straightforward analog-domain limiter. Ported box, ~200W class AB amp.
Save us from "junk" bass!! If I need to choose between zero bass and the typical, 'false' bass -- well, that's an easy one actually ...
The cone can only follow the speed of sound, but that is, the speed of sound in the material the cone is made of.
The propagation of sound in solids is typically orders of magnitude faster than in air, with berrylium being the highest I know of, even faster than in diamond.
In short, the cone will typically follow the movements of the VC faster than the speed of sound in the air.
Do you see your contradiction here?
The problem is that recordings are mixed and mastered to have the intended bass balance on a wide range of non-servo'ed speakers. They would need a different bass balance and EQ to sound "right" on servo'ed systems. This implies that a servo'ed system should have optional additional level and EQ adjustment to restore the "as the artist intended" sound, which partly defeats the purpose of servo'ing in the first place...
No i dont see the contradiction nor correlation of comparing the operation of a cutter to that of a subwoofer ..
I have done my own recordings in the past , there was no need for special Eq, tricks to reproduce the bass . It either sounds like the input or it doesnt , servo woofers i have heard does not , now feel free to point me to the ones you think sound natural ...
I'm all ears ......
I have done my own recordings in the past , there was no need for special Eq, tricks to reproduce the bass . It either sounds like the input or it doesnt , servo woofers i have heard does not , now feel free to point me to the ones you think sound natural ...
I'm all ears ......
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Part of the Yamaha NS-1000 legend, I believe - berrylium dome midrange, berrylium dome tweeter.
Any idea of how titanium fares in these waters?
Diamond is where it's at these days , buddy ....
DIAMOND tweeters? Kid me not???
Whats an Isobaric ..? you must mean bandpass ......
A drive unit hidden in the box to get slightly better performance for the size used . A bit like the liquid idea with greater practicality .
If below 60 Hz a solenoid can be used if digital delay employed. The solenoid is very slow . If out of step the dynamics will be lost . This happens with pipe organs if feet don't time with fingers . A friend adapted solenoids to make Sub Sub's . Very big PA . None of the notes would be audible . Hard fast bass would result despite the solenoid being in itself slow . My friend never showed me the exact way he did it . It was slamming the metal into a horn from what he said . Nigel Copin , lets honour his name . Mr C gave me all his transistors and a nice drill press when he walked away from audio . So bad for him it was a divorce .
I think the Russian had a strange contract on supplying beryllium . That is they could call it back at any time . That implied the NS 1000 tweeters go home to the then USSR ( Yamaha rep said , can you trust what they say , too complicated to be a lie ) . Also don't let the kids lick them .
Frankly Nige, I think that's just a wild spin. I honestly cannot see any large corporation putting itself in the precarious position of possibly being blackmailed by their supplier. Besides, even if they wanted to, how could they repossess all the units sold? Legally, after sales, they become the property of their owners, and there's nothing Yamaha can do about it.
But it does give them an aura of the sinister, a great sales spin, if you ask me. Complicated just enough to be impossible to verify.
I think it was the sort of fun the Soviets would get up to . It's called bluff and almost charming . It was about weapons I think . My understanding was a poor translation of a Soviet contract . If in my brand of English one I could have written myself . Ambiguity is my middle name .
When I was little my father was looking at a BSA C15 motorcycle service manual . It had letters and arrows on the diagram . My dad read out " P in the clutch " to which he mumbled " I would if I thought it would help " .
When I was little my father was looking at a BSA C15 motorcycle service manual . It had letters and arrows on the diagram . My dad read out " P in the clutch " to which he mumbled " I would if I thought it would help " .
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