peranders said:
The numbers are represented in pf capacitance per meter.
Don't remember the exact numbers of Kimber 4TC and 8TC (double capacitance of 4TC!).
Google a little and you'll find it.
The construction of the cable (crossed) gives it mid to high capacitance.
Low capacitance cables are figure-of-8 or flat cables, like Nordost and others.
That's why I initially had better results with cheap Supra 2.5, these chips don't like capacitive loads.
It's sorted, and I'm sure that if my amp works very well with a 5 meter pair of Kimber 4TC, it will work with almost everything.
The safety circuits has nothing to do with the sound (or?) but I haven't got those because I think this integrated solution has got very good properties when it comes to reliability. Has anybody broken a correctly connected LM3886, LM3875, LM4870? Please report!Peter Daniel said:
Pavel is right though: The parts cost nothing. They only take up a little space.
Those chips are very hard to get broken. I was running mine with only one rail connected, and it didn't brake the chip nor speakers. I had the output shorted for 30min and nothing happened. I dropped my amp from second store window, and it still working😉
I am really looking forward towards a FAIR(and I do stress that) face to face comparison between a 47 style GC and a Pavel style GC...
Of course I would like to have a better design coming from europe, but I don't care where it comes from if it sounds better(us, canada, china, europe or any other place on earth) and doesn't cost a ton on c@sh nor does it consume 100watt+ at idle.
Of course I would like to have a better design coming from europe, but I don't care where it comes from if it sounds better(us, canada, china, europe or any other place on earth) and doesn't cost a ton on c@sh nor does it consume 100watt+ at idle.
carlosfm said:
The numbers are represented in pf capacitance per meter.
Don't remember the exact numbers of Kimber 4TC and 8TC (double capacitance of 4TC!).
Google a little and you'll find it.
The construction of the cable (crossed) gives it mid to high capacitance.
Low capacitance cables are figure-of-8 or flat cables, like Nordost and others.
That's why I initially had better results with cheap Supra 2.5, these chips don't like capacitive loads.
It's sorted, and I'm sure that if my amp works very well with a 5 meter pair of Kimber 4TC, it will work with almost everything.
4 TC 144 pF per meter
8 TC 328 pF per meter
It means capacitance in a normal room of < 1 nF. Isn't this "small"? Nothing to worry about?
peranders said:
That's high.
It's for one meter cable.
Problem is most other manufacturers don't give you those specs.
An amp should be able to take 100 nF, or at least 10 nF without problems. If not redesign it.carlosfm said:
peranders said:
Tell that to National engineers.
I'm telling you that with direct output the amp sounds bad with these cables.
I'm telling you that with zobels it gets a little better, but not perfect.
I'm telling you that the solution I have is the best I found and solves it.
And I'm tired.
Gotta go drink a cold beer.😀
Note: not every amp works fine with Kimber speaker cables, you know?
Or other high-capacitance cable.
And sometimes you change the speaker and the problem is gone.
Is it only the amp?
No.
Do you have answers for everything, P-A?
No.
Upupa Epops said:
Interesting, but that reference is too cryptic for me. Is there another description for "hf power coaxials"? Sorry if this is dumb question.
Sheldon
Edit: Turns out that was a somewhat dumb question. Found it by searching Andrew Coaxial - duh. Ok, so here's a not quite so dumb question: Which of their cables are you referring to? I'm assuming the 1/4" variety?
Sheldon, he means that the amp is picky with cables.
And the best cable he tried is a coaxial 75 ohm TV cable.😱
47 Labs made the same thing: they sell the best cable for their amp.
And the best cable he tried is a coaxial 75 ohm TV cable.😱
47 Labs made the same thing: they sell the best cable for their amp.
Yeah, no use in trying to redesign the wheel right?
😀
Why not if you have control of the roads too?
An externally hosted image should be here but it was not working when we last tested it.
😀
Why not if you have control of the roads too?
Sheldon said:
Andrew cables apparently were the basis for the well regarded JPS cables. They have a solid copper shield, so are not easy to handle. The center conductor is a copper/aluminum solid wire, which shouldn't be trusted in most circumstances for audio. But it seems to work. The LFS5 is a good place to start.
That Andrew cable is mostly used for radio antennas, so getting a few meters to try shouldn't be hard.
If you follow the instructions on TNT's article written by Thorsten Loesch, using a coaxial cable to build a speaker cable, it's only a matter of replacing the original for the Andrew.
Such arrangement has a very low capacitance.
Carlos
And do not forget shielding effect of the coaxials. All of that HF mess is best avoided or supressed. Terminating resistor at speaker box terminals also helps, as speaker + crossover+wires are inductive in HF range. May sound silly, but greatly reduces HF mess at the speaker cable terminals.
carlmart said:
These guys seem to stock Andrew cable and sell by the foot:
http://www.cablexperts.com/cfdocs/cat.cfm?ItemGroup=11&itmsub=0&bskt=0&USA_ship=1&c=0
The type is LDF150. As you can see capacitance is low: 23.4pF/ft.
Price is reasonable, so it deserves a try.
There's a potentially even better cable, coaxial too, called Tflex 402. It uses teflon dielectrics and silver-plated copper. It's harder to find, but it's probably one of the best there is.
One of the few retailers might be this:
http://www.semflex.com/pdf/SM Series.pdf
Carlos
Why Andrews?
I mean, 5 minutes car drive I have Tèlèves 75 ohm cables for sattelite/TV, some models of this cable are pure OFC copper, including shield.
I mean, 5 minutes car drive I have Tèlèves 75 ohm cables for sattelite/TV, some models of this cable are pure OFC copper, including shield.