Yes. To the point of creating a lf sound which would be unnatural, in the sense it cannot occur in nature, because that would offend causality - artefacts arise at times before the event happens. Welcome to the pleasuredome of digital filters, where such things are the everyday norm
We have too many here.
Shot one to make the old school salt/hickory bacon with.
Don't need to refrigerate , so much better than chemikill store bacon.
Then they do it larger scale here - Country Hams, Benton's Country hams, townsend, tn,hams, Country bacon, Bacon, smoky mountains, smoky mountain hams
(below)
10X better meat than any corporate junk - I can't eat most store meat.
Our local market is all N. carolina beef as well , no imports (I've seen the
meat a walkin').
OS
This goes some way in explaining why I, even with limited experience of the South dating way back to 1970, stated on impulse that if I were to live in USA, it would have to somewhere in the South. And I never got further than Virginia. All other times, I've been in the North, like Boston, NYC and Washington DC. A mentality I can relate to, the South.
Not that I'd turn down visiting the West Coast, to the contrary, I'd love to see San Fran, better known as the birthplace of Clint Eastwood.
The original question was negative effects of high pass analog filter to reduce the parasitic increase of levels of very low frequencies due to the resonance of the arms in turntables. (spring of the cantilver suspension with mass of the arm+head)
If some bump exists in the response curve, due to this arm resonance, it create a group delay change by itself. Even if such an analog filter is not exactly correcting-it, by an exact opposite response curve, it will go the right way, and , at least, will reduce this phase turns effects, am-I wrong ?
This said, if someone cannot afford the evils and horrible artifacts created by all those digital infernal machines, and, still today, prefers vinyls and turntables, it is the proof that all those group delay and phase distortions, introduced by the analog magnetic tape recorder/player, LP cutting machine and his vintage turntable... are not so bad to his ears.
No need to add a GPS to your horse carriage: your horse know the way back to home, even if you are dead drunk.
On my side, i don't like the smell of the dung, never drink too much, so, I go for digital and GPS in my car as much as I can.
No need to add a GPS to your horse carriage: your horse know the way back to home, even if you are dead drunk.
On my side, i don't like the smell of the dung, never drink too much, so, I go for digital and GPS in my car as much as I can.
artefacts arise at times before the event happens. Welcome to the pleasuredome of digital filters, where such things are the everyday norm
I believe the correct way to explain this is that artifacts occur and after that the delayed main even occurs. Causality preserved ;-)
Agreed?
Jan
There has been at least one case of some hooray being prosecuted for being drunk in charge of a horse. The defense was as you say 'the horse knew the way home so I was not in charge of it'.
Hm, Esperado
On my rig i have a switchable subsonic filter.
With big woofers and warped records it is clearly better to use the filter, reducing rumble, acoustic feedback, amplifier and woofer stress and giving cleaner sound.
But if i have nonwarped records , thus the resonance add very small amount of rumble or if i use small speakers limited to maybe 50 Hz, my acoustic impression is that the spatial reproduction is shrinking, this means the filter has some audible negative effect.
So i don't know why this happens. Do you have an idea what causes this or am i misleaded by listening impression?
The Arm/ Cart Fres is around 9 Hz and the TT has no spring suspension.
The System works with Tact Room correction and goes really low if desired by programming.
On my rig i have a switchable subsonic filter.
With big woofers and warped records it is clearly better to use the filter, reducing rumble, acoustic feedback, amplifier and woofer stress and giving cleaner sound.
But if i have nonwarped records , thus the resonance add very small amount of rumble or if i use small speakers limited to maybe 50 Hz, my acoustic impression is that the spatial reproduction is shrinking, this means the filter has some audible negative effect.
So i don't know why this happens. Do you have an idea what causes this or am i misleaded by listening impression?
The Arm/ Cart Fres is around 9 Hz and the TT has no spring suspension.
The System works with Tact Room correction and goes really low if desired by programming.
I don't know. The only thing I'm sure of is there is no localisation at such low frequencies. Just the presence/misses of very low frequencies change the feeling of the "volume" of the soundstage. All along with the delais of the first reflections (echos) and the duration of the reverberations in the original recording. But the delays involved are a lot larger than group delay artifacts.
During mixing, we use delays added to the left channel from instruments situated on the right channel (and opposite) to create artificial lateral walls to the sound stage, and longer delays in the center to give a feeling of the length of the concert hall.
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I have an unusual listening test over in 'Everything Else'. This one is very different
http://www.diyaudio.com/forums/everything-else/275635-listening-test-different-kind.html#post4354823
http://www.diyaudio.com/forums/everything-else/275635-listening-test-different-kind.html#post4354823
Thank you Esperado
Of course low notes are in mono on records and no localisation therefore possible.
Your description abouth delay when mixing seems to be a possible reason for what i hear with the big system, but small speakers limited at 50 Hz?
I think a comparison with master tape could give a better conclusions, but i have no access therefore.
Of course low notes are in mono on records and no localisation therefore possible.
Your description abouth delay when mixing seems to be a possible reason for what i hear with the big system, but small speakers limited at 50 Hz?
I think a comparison with master tape could give a better conclusions, but i have no access therefore.
You are welcome. I did the measurements for myself (to see with my eyes how much twisted is the phase response with the settings I am using in my MiniDSP).
For the measurements, I used only a pc, a soundcard and the 2x4MiniDSP (the plug in is the 2.1 advanced)
Details:
Sound card was connected in the standard way (Card’s L_Out to Card’s L_In and to DUT_In. DUT_Out to Card’s R_In)
DUT_In was the Analog_IN2 of MiniDSP
DUT_Out was the Analog_OUT2 of MiniDSP
Test signal was 12dB below FS of MiniDSP input level.
No attenuation at the input/output.
Digital volume fully CW.
No delay and no equalisation.
Only the selected 15Hz LP filter in Crossover section was intervening between Input and Output.
The sinusoidal signal sweep was generated through REW V 5.11
[Measure]>[SPL] (see att. 2)
The sweeps are recorded automatically by REW.
There were generated one record for each selected filter, one record for no filter and one record for card’s loopback response.
I exported the data of all measurements in .txt form (see att.3)
There is one .txt file generated for each measurement. It contains three columns: freq., SPL, Phase and they are space delimited. With the above settings, there are 858 data triplets (rows). (*)
These I imported to a spreadsheet (Excel).
The main reason for using the spreadsheet is that I wasn’t completely satisfied with the calibration results of the sound card below 20Hz. So for to completely null the effect of card’s response on the filters response, I subtracted each measurement’s data from the card’s loopback data within Excel.
As a bonus from using the spreadsheet, I numerically performed phase inversion and phase unwrapping, which I neglected to do before exporting the data.
Now I will try to extract the GD from the phase data.
If for any obscure reason you want the data you saw on the diagrams, I can make them available.
What “FP” means?
George
(*) For some obscure reason the recorded data starts at 2Hz, although the sweep starts from some mHz.
Attachments
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Oh, now I understand, thanks Ed.
Well, these are unreachable heights of knowledge for me.
I am only able to move virtual sliders and press virtual push buttons to alter pre-programmed parameters.
George
This goes some way in explaining why I, even with limited experience of the South dating way back to 1970, stated on impulse that if I were to live in USA, it would have to somewhere in the South. And I never got further than Virginia. All other times, I've been in the North, like Boston, NYC and Washington DC. A mentality I can relate to, the South.
Not that I'd turn down visiting the West Coast, to the contrary, I'd love to see San Fran, better known as the birthplace of Clint Eastwood.
There is the good and bad -
The good - They won't be outright rude to you (like in NY).
The bad - It's harder to figure if you actually have offended (they won't tell you).
Once you "reckon" these "ways" , be able to slow down - take it easy ....
the better aspects (the food and friends) become available.
OS
You are right. The arm resonance is minimum phase, and so can be exactly offset in both frequency and phase response by a (min phase) analog filter, as most analog filters are. This is not the case for correction by linear phase filter, such as digital IIR.
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Well, it's a philosophical matter, but the fact is that the click marking the start of the kick drum event is heard with a certain pre-ring or 'reverse reverb' in the case of a linear phase filter, even after latency is compensated. So that's a violation of causality in the sense it can't happen naturally.
Ohh. I thought that the delay between preringing and the main event was actually the latency (plus some delta-T).
Jan
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