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jmsoto
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Short Speaker Cable+Long Component Cable Vz. Long+Short?

I have 2 mono amps, should I place the amps near each speaker, in favor to shorter speaker cables, or near the pre-amp, in favor to the shorter component cable but longer speaker cables???

ncdrawl
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

The shortest runs should be the speaker wire. This is where balanced connections in a preamp/amp have an advantage, running cable over long distances.

anyway, get those blocs near speakers, not the preamp.

Jan Vigne
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

You need to consider the output impedance of your pre amplifier. If the value stated in the manufacturer's specs is higher than 600 Ohms, you should place the amplifiers close to the pre amplifier to avoid frequency response errors caused by the impedance. The exception here would be if your power amplifiers have an exceptionally high input impedance, say, over 200kOhms. Even then your placement of the power amp should be as close to pre amp as possible to avoid problems.

If the pre amp's output impedance falls beneath a stated 600 Ohms, then you can drive a hundred feet of low capitance interconnect without problems (assuming the number stated is in reality a true value).

SAS Audio
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

Here is a quote from one of my tech pages. One will notice that output Z is not that important in an amp unless large lengths of ICs are used.

Changing from 100 ohms to 2k ohms output. Using IC with 50pf of capacitance causes approx ,02db change in response at 100khz.

Using IC with 250pf of capacitance causes approx ,4db change at 100khz.


Quote:
Decreasing the ratio from 100:1 to 10:1 results in virtually no increase in harmonic distorion. For example if the total harmonic distortion at 2v rms output measures .01% (-80db) using the 100:1 ratio, changing to 10:1 raises the distortion by approximately .012% to -79db, a rise of approx 1db. Not much difference is it.

Let's check for any high frequency response advantages. If one uses a high capacitance interconnect cable (IC), say 250pf of capacitance, and the output impedance changes from 2000 ohms to 100 ohms, the frequency response changes approx 0,4db at 100,000 cycles per second.

Using a 50pf interconnect cable results in less than 0,02db change at 100khz. By the way, everyone knows that capacitances should be minimized with interconnect cables. (However, rarely, a longer IC with higher capacitance is neccessary as there is no choice.) Actually a major portion of the loss in high frequency response is due to the volume control resistance/input tube capacitance relationship, not from the preamplifier output Z.

The added buffer stage does not do much except contribute artificial flavors.

By the way, using "balanced" components means extra transformers, or many extra parts (dozens if not hundreds) including at least one extra power supply which is a major contributor to sonic degradation. One also sees balancing and drifting problems as well.

When one learns details about designing balanced components, it is not as glamarous as it appears.

ajschmidt
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

the shorter the speaker cable run the lower the resistance, but running a larger gauge wire would be my first step. I start with 10 or 8 gauge wire with longer runs to get placement as good as it can be, then trim to the shortest lengths and terminate. High power cable (ie speaker wire) is far more resistant to RF interference than low power interconnects (grounded is a must, and do not lift ground, use one mains outlet). If you've ever built a cristal radio, you know the power of RF. That is your worst enemy, not the longer speaker cable runs.

SAS Audio
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?


Quote:
the shorter the speaker cable run the lower the resistance, but running a larger gauge wire would be my first step. I start with 10 or 8 gauge wire with longer runs to get placement as good as it can be, then trim to the shortest lengths and terminate. High power cable (ie speaker wire) is far more resistant to RF interference than low power interconnects (grounded is a must, and do not lift ground, use one mains outlet). If you've ever built a cristal radio, you know the power of RF. That is your worst enemy, not the longer speaker cable runs.

I am not sure if you are addressing me or simply using the reply button to post a general response? Anyway, I agree with you Ajs.

cyclebrain
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

Why no mono-block integrated amps?

bertdw
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?


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Why no mono-block integrated amps?


Having two separate volume controls is a pain???

KBK
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

I go for short runs of both type of cable, if I can.

I dare to cut holes in walls..and put the entire system in another room. Then short run of speaker cables through the hole in the wall. One hole behind each speaker, to the monoblock on the other side. If I have remote volume..then I use a infrared remote extender device.

That's a pretty decent way to do it. Tiny holes in modern cheap drywall are pretty easy to fix/clean up.

I'd rather be forced to have stonemasons come in to cut holes through the castle walls to save $200K on cables...but.. no such luck. Dang.

cyclebrain
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?


Quote:

Quote:
Why no mono-block integrated amps?


Having two separate volume controls is a pain???

Not at all in this digital age, and can only help the R/L isolation.

Stephen Scharf
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Re: Short Speaker Cable+Long Component Cable Vz. Long+Short?

Interestingly, Maple Shade Audio recommends running the IC's as short as possible, and using speaker cables a minimum of 8 ft in length, as he says that this arrangement sounds best after extensive testing.

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