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Old 13th June 2007, 12:33   #6166
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Hmm I guess it has more to do with the Frequency response of various materials.
I am sure if you connect one end of the cable to a Frequency generator, and other end to a high rez oscilloscope, and then do a gain/freq plot, these cables will have different results.
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Old 13th June 2007, 12:35   #6167
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Quote:
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Hmm I guess it has more to do with the Frequency response of various materials..
I am not even sure of that. These cable guys have done a number of tests on these cables. skin effect, reactance, FFT, even impulse waterfalls. A good cable is a mix of science and art.
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Old 13th June 2007, 13:40   #6168
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yup cable specs vary depending on application. I have a full 200+ catalogue on types of cable which i use at work.

they depend on application like audio, video, lvds even that again is depending on max frequency and voltage/current chars.

needless to say they do cost a bomb. The frequency response can be gauged also using a spectrum analyser.
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Old 13th June 2007, 13:49   #6169
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Quote:
Originally Posted by tsk1979 View Post
Hmm I guess it has more to do with the Frequency response of various materials.
I am sure if you connect one end of the cable to a Frequency generator, and other end to a high rez oscilloscope, and then do a gain/freq plot, these cables will have different results.

How about Optical cables?
Some items has an option for optical cables. Is it better solution?
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Old 13th June 2007, 14:38   #6170
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Dhar, I think you are talking about digital audio connections. Never heard of optical cables in analog audio domain. Do they exist?
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Old 13th June 2007, 15:14   #6171
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Santhosh,
yes i mentioned that in the digital audio context.
For analog i don't know. thats y i put up the question.
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Old 13th June 2007, 18:47   #6172
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hi,

need help getting the heat shrink tubing. what do you call the heat shrink tubing in desi language? its not available here in my city or probably they call it something else. also when i bought my l&t wire from the auth dealer i saw a roll of tube 40mm in dia, the guy told me its heat shrink tubing(he wasnt sure though). can that size be used for a 25mm^2 wire? what would be the perfect size for the above wire? i badly need cause the install looks ugly with insulation tape.

can anyone help me with fiber glassing? any online tutorials, what material i need to buy etc etc. my hand are itching to do something as they are idle for quite a while. thought ill give it a try.

cheers
clip
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Old 13th June 2007, 19:06   #6173
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Quote:
Originally Posted by navin View Post
Tsk.
\

A pair of 6x9 are great up to 40Hz or so. High SPLs below that frequency and they will hit their limits. a 12" sub however can go almost an octave lower (25Hz is not impossible) before the same signs are felt.
navinji, can you explain in detail the term octave? db/octave etc. i tried searching but couldn't find a good explanation.

cheers
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Old 13th June 2007, 19:31   #6174
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Quote:
Originally Posted by Dhar's View Post
Santhosh,
yes i mentioned that in the digital audio context.
For analog i don't know. thats y i put up the question.
Just as santhosh mentioned, Digital Optical Fibre is always used ONLY to carry digital signals in light form. Bits and bytes, flips and flops only. Even in the digital domain, I am not a fan of this medium.

Beautiful and pure, analog audio, is not carried through this medium.
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Old 13th June 2007, 23:28   #6175
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navinji, can you explain in detail the term octave?
Huh? One Octave in Music is one doiubling of frequencies. Middle C (C3) to "Sol Fa" (C4) is one octave. Similarly 500Hz to 1000Hz is one octave and so is 500Hz to 250Hz.

Now when you say a Low Pass filter has a slope of 6db/oct. it means that if the knee of the filter is at 500Hz it will attenuate 1000Hz by 6db, 2000Hz by 12db, 4000Hz by 18db and so forth.

Octave, Octal, Octagon are all Latin derivations.
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Old 14th June 2007, 11:09   #6176
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firstly what is octave...

It is the interval between one musical note and another with half or double its frequency.


for further read :- Octave - Wikipedia, the free encyclopedia

now what is slopes...

Crossover Slope

a little more detailed one explained here with DIY projects.

Passive Crossover Slopes
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Old 14th June 2007, 12:14   #6177
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Sensitivity Puzzle:
JBL P1222 - 97db (2.83v@1m)
Kicker S12L5 - 88.8db (1w/m)

Which one has more sensitivity?
(Both values from respective brochures)
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Old 14th June 2007, 12:21   #6178
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Quote:
Originally Posted by Dhar's View Post
Sensitivity Puzzle:
JBL P1222 - 97db (2.83v@1m)
Kicker S12L5 - 88.8db (1w/m)

Which one has more sensitivity?
(Both values from respective brochures)
Jbl because... 2.83v=1w at 8 ohms and at 4 ohms it will be 2 watts but what are the impedance of the drivers ??

Last edited by low_bass_makker : 14th June 2007 at 12:24.
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Old 14th June 2007, 12:26   #6179
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Actually only numbers specified as dB @ 2.83v/1m should be called "sensitivity", whereas the number dB @1w/1m should better be called "efficiency". The first number gives an idea as to how load a speaker will sound when driven by a given amp, irrespective of speaker's impedance. If you are comparing the 2nd number then you will have to consider its impedance, because the amount of power it can extract from the amp will depend on that. Lower the impedance, more will be the power fed by amp. But you need to be aware of how low an impedance your amp can drive safely.
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Old 14th June 2007, 12:26   #6180
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Both should be 4 ohms.
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