double posting==no no! (if you feel as if youve posted the question in the wrong place, the mods will move it)

anyway..

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.

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).

There Is a "delete this post" option.

I double-posted a couple of times thru some sort of software screwup before I picked up on it, but it is there; you click the "edit" button and then after you return to the edit area, go to the bottom and there is a "DELETE THIS POST" button next to the "CHANGE THIS POST" button.

It certainly depends on the precise amplifier and preamplifier involved, but my opinion would be that many unbalanced interconnects over two meters in length can produce undesirable effects (BALANCED interconnects can be as long as you want with no problems).

Heavy gauge speaker cables (#10 or #12 gauge) can usually be up to 15 feet long with no problems, but there are a few speakers where that generalization will not hold up.

Hi JM,

I wrote a paper on my website covering some basic information and IC effects were included (single ended design). Here is a portion from that article in which I was discussing if or any problems with preamplifier output impedance (Z).

Let's check for any high frequency response advantages (using a low output buffer stage). If one uses a high capacitance interconnect cable (IC), say 250pf of capacitance, and the output impedance (of the preamplifier) 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, it is good that IC capacitance should be minimized. (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.

-----

It is good to check the capacitance of the IC when purchasing as I have seen as high as 475pf for one meter, and 15,500 pf (.0155uf) for 20 feet. Both are very poor imo.

Hope this helps solve your dilemma JM.

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

OMG! 0.4db down at 100 KHz, that must sound so awful.
Meanwhile my speaker/room response varies +/-5db in the audio band.

The only way to answer a question like this with some assurance is to know the cable capacitance, resistance, amplifier input and output impedence, preamp output impedence AND DRIVE CAPABILITY ...

Sorry.

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The only way to answer a question like this with some assurance is to know the cable capacitance, resistance, amplifier input and output impedence, preamp output impedence AND DRIVE CAPABILITY ...

Sorry.

"The only way to answer a question like this with some assurance"? How can you say that? You only used measurable scientific information in your analysis. You completely negleted to take into account the effects of magical interconnect cables that take the electrical signals fed into them and output a much improved signal.

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The only way to answer a question like this with some assurance is to know the cable capacitance, resistance, amplifier input and output impedence, preamp output impedence AND DRIVE CAPABILITY ...

Sorry.

"The only way to answer a question like this with some assurance"? How can you say that? You only used measurable scientific information in your analysis. You completely negleted to take into account the effects of magical interconnect cables that take the electrical signals fed into them and output a much improved signal.

Oh, that Hertz, cyclebrain! That really Hertz. Do I sense some resistance here, to impede or not to impede, perhaps you're using inductive logic to insulate yourself.

J_J, you should leave this to people with the appropriate expertise, perhaps Dr. Kunchur. You are not properly trained to pretend any expertise in this matter.

Dr. Kunchur is a physicist, after all. You are what, a listening programmer of some sort? Why would we listen to your thoughts on wires?

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J_J, you should leave this to people with the appropriate expertise, perhaps Dr. Kunchur. You are not properly trained to pretend any expertise in this matter.

Dr. Kunchur is a physicist, after all. You are what, a listening programmer of some sort? Why would we listen to your thoughts on wires?

Wire you asking? What kind of terminal inquisition are you conducting, anyhow, leaving your horse at the binding post and letting the copper get you.

Steve! How ARE you, guy? I thought we'd lost you.

Oh, wait, it's just the Buddha, met on the road, or something.

Does anyone here know how to properly conduct themselves in a discussion forum? Maybe some of you should just go Ohm. ReVolting!

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Does anyone here know how to properly conduct themselves in a discussion forum? Maybe some of you should just go Ohm. ReVolting!

I try to stay current, after all, so I don't get charged for exceeding capacity, just like Henry. I guess if you decided to buy it was a Farad, anyhow.

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

OMG! 0.4db down at 100 KHz, that must sound so awful.
Meanwhile my speaker/room response varies +/-5db in the audio band.

Hi Cycle,

A couple of reasons to provide this shocking information to the public.

1) .4db does make some sonic difference in a good system. But it takes a fairly high IC capacitance with 2k ohm output impedance (Z). I prefer to keep the IC capacitance as low as possible to minimize capacitance.

2) To let people know that a buffer stage is not necessarily an advantage. In fact, it can detrimentally affect the quality of the music more than the change in response.

Some use a buffer stage as a marketing tool and seem to infer that those who do not produce inferior equipment. Just the opposite is generally true.

Cheers.
Steve

One good turn deserves another. (recoil from this?)

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

OMG! 0.4db down at 100 KHz, that must sound so awful.
Meanwhile my speaker/room response varies +/-5db in the audio band.

Hi Cycle,

A couple of reasons to provide this shocking information to the public.

1) .4db does make some sonic difference in a good system. But it takes a fairly high IC capacitance with 2k ohm output impedance (Z). I prefer to keep the IC capacitance as low as possible to minimize capacitance.

2) To let people know that a buffer stage is not necessarily an advantage. In fact, it can detrimentally affect the quality of the music more than the change in response.

Some use a buffer stage as a marketing tool and seem to infer that those who do not produce inferior equipment. Just the opposite is generally true.

Cheers.
Steve

Kudos for the civil response to my sarcastic post.
But I still stand by my view that looking at things from an overall system level, -0.4db at 100khz relative to the huge variation in response of all speakers and the interaction of speaker/room response is negligable.

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Quote:
If one uses a high capacitance interconnect cable (IC), say 250pf of capacitance, and the output impedance (of the preamplifier) changes from 2000 ohms to 100 ohms, the frequency response changes approx 0,4db at 100,000 cycles per second.

OMG! 0.4db down at 100 KHz, that must sound so awful.
Meanwhile my speaker/room response varies +/-5db in the audio band.

Hi Cycle,

A couple of reasons to provide this shocking information to the public.

1) .4db does make some sonic difference in a good system. But it takes a fairly high IC capacitance with 2k ohm output impedance (Z). I prefer to keep the IC capacitance as low as possible to minimize capacitance.

2) To let people know that a buffer stage is not necessarily an advantage. In fact, it can detrimentally affect the quality of the music more than the change in response.

Some use a buffer stage as a marketing tool and seem to infer that those who do not produce inferior equipment. Just the opposite is generally true.

Cheers.
Steve

Kudos for the civil response to my sarcastic post.
But I still stand by my view that looking at things from an overall system level, -0.4db at 100khz relative to the huge variation in response of all speakers and the interaction of speaker/room response is negligable.

Hi Cycle,

If you read my initial post again, and if you had actually quoted the entire post, I also stated .02db with 50pf of IC capacitance. My initial point was that a buffer stage is not needed for great fidelity. In fact, I stated that the extra stage can be more detrimental to sound quality than the lower frequency response caused by IC capacitance.

I was mainly addressing those who market products hyping buffer stages as superior while slighting those who do not use a buffer stage. I take it you agree that a buffer stage is not needed with a 2k ohm output stage.

Of course if one uses high plate resistance (Rp) tubes like 12at7, 12ax7, 6sn7s etc, one does need a buffer stage as the frequency response is heavily affected by interconnection cable capacitance. One can understand the marketing tatic when using such high Rp tubes, to justify their product's design while slighting the competition that does not require this extra stage.

If you have a problem with my comment that sonic changes occur at modest db changes in a good system; be my guest. That is up to you. But remember we are talking frequency response (FR) changes over many octaves wide. As my extensive research suggests and Dr. Kunchur concurs in his papers, ultra sonics do affect what we hear, in one way or another. I also want to minimize or eliminate each and every restricting mechanism in the system. The more one has, the more restrictive the system.

As a suggestion, you may wish to do your own experimention if you have not already done so. By the way, Van Alstine, scientific/objectivist camp, claims sonic changes occur to at least 4mhz (posted in Audio Circle forum some time back), although I have not checked, and personally I doubt it. But that is my opinion.

By the way, I use one meter ICs and 5 foot speaker wires.

Cheers.
Steve

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I prefer to keep the IC capacitance as low as possible to minimize capacitance.

Very insightful.

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2) To let people know that a buffer stage is not necessarily an advantage. In fact, it can detrimentally affect the quality of the music more than the change in response.

Some use a buffer stage as a marketing tool and seem to infer that those who do not produce inferior equipment. Just the opposite is generally true.

You are saying that adding more stuff in the signal path probably won't improve the sound?

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By the way, Van Alstine, scientific/objectivist camp, claims sonic changes occur to at least 4mhz (posted in Audio Circle forum some time back), although I have not checked, and personally I doubt it. But that is my opinion.

The inductance of a speaker coil causes its impeadance value to increase at high frequencies to the point of causing it to not dissapate any energy at those high frequencies.

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By the way, I use one meter ICs and 5 foot speaker wires.

I would never mix one meter ICs with 5 foot speaker wires.
Everyone knows that mixing meters with feet causes differential measurement unit distortion.

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I prefer to keep the IC capacitance as low as possible to minimize capacitance.

Very insightful.

I thought so. Really emphasizes the point doesn't it.

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2) To let people know that a buffer stage is not necessarily an advantage. In fact, it can detrimentally affect the quality of the music more than the change in response.

Some use a buffer stage as a marketing tool and seem to infer that those who do not produce inferior equipment. Just the opposite is generally true.

You are saying that adding more stuff in the signal path probably won't improve the sound?

That is an interesting question Cycle . As a simple example, if the first stage is too full (from absolute accuracy, "invisible") or has too high of an output impedance (Z), then a lighter sounding or lower output Z buffer stage would tend to correct the error in the first stage. I guess those guys do need an extra stage to improve the sound after all.

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By the way, Van Alstine, scientific/objectivist camp, claims sonic changes occur to at least 4mhz (posted in Audio Circle forum some time back), although I have not checked, and personally I doubt it. But that is my opinion.

The inductance of a speaker coil causes its impeadance value to increase at high frequencies to the point of causing it to not dissapate any energy at those high frequencies.

Yep. However the rise time changes and is reflected in the total rise time of the system, does it not.

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By the way, I use one meter ICs and 5 foot speaker wires.

I would never mix one meter ICs with 5 foot speaker wires.
Everyone knows that mixing meters with feet causes differential measurement unit distortion.

I forgot that pesky differential measurement unit distortion. Thanks cycle.

It gets quite interesting, Cycle, when one works with ultra sonic frequencies and its effect. One sees things in a different light from the pencil pushers.

Cheers.
Steve

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It gets quite interesting, Cycle, when one works with ultra sonic frequencies and its effect. One sees things in a different light from the pencil pushers.

Cheers.
Steve

I work daily with two frequencies. Just under 10Ghz and just under 20Ghz. X Band and Ku Band radar.

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It gets quite interesting, Cycle, when one works with ultra sonic frequencies and its effect. One sees things in a different light from the pencil pushers.

Cheers.
Steve

I work daily with two frequencies. Just under 10Ghz and just under 20Ghz. X Band and Ku Band radar.

Ah I am talking about even higher frequencies.
I know I need my hands slapped with a ruler.

Take care and have a great Labor day weekend Cycle.
Steve

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I work daily with two frequencies. Just under 10Ghz and just under 20Ghz. X Band and Ku Band radar.

Heh.

Somehow, though, I suspect those are EM radiation, not compression waves in a very non-ideal gas.

But when you get well into the ultrasonic range, it's very true that the linearity of sound propagation goes right out the window. Same is true for high levels.

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It gets quite interesting, Cycle, when one works with ultra sonic frequencies and its effect. One sees things in a different light from the pencil pushers.

Cheers.
Steve

I work daily with two frequencies. Just under 10Ghz and just under 20Ghz. X Band and Ku Band radar.

You must be one of those guys that wants to give me a ticket just because I'm traveling 30 MPH over the speed limit.
Gee officer, I wasn't speeding. It was low level flying.

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You must be one of those guys that wants to give me a ticket just because I'm traveling 30 MPH over the speed limit.
Gee officer, I wasn't speeding. It was low level flying.

Not even close. I'm the guy that gives you a ticket for driving in the fast lane holding up traffic or failing to maintain your lane when making a turn. It's not the speed that's important, it's the competance and focus that matters. BTW my last ticket/arrest was for 130mph+ (the top speed of the unmarked car trying to keep up).

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[Ah I am talking about even higher frequencies.
I know I need my hands slapped with a ruler.

Take care and have a great Labor day weekend Cycle.
Steve

I also forgot to mention the other high frequencies that I deal with daily. Light. Very short wavelengths. I'm currently working on an amplifier/speaker that is flat from DC to light. Uses vacuum tubes and a special combination wire and fiber optic transformer in the output stage. Initial tests have had problems. After some problems with test subjects I have had to limit the bandwidth to just below the visible spectrum.

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Wire you asking? What kind of terminal inquisition are you conducting, anyhow, leaving your horse at the binding post and letting the copper get you.

I think we're all Bozos on this buss!

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Wire you asking? What kind of terminal inquisition are you conducting, anyhow, leaving your horse at the binding post and letting the copper get you.

I think we're all Bozos on this buss!

Or maybe just reFUSE.

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I think we're all Bozos on this buss!

Oh my God there's a Lobster loose.

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I think we're all Bozos on this buss!

Oh my God there's a Lobster loose.

But I was waiting for the electrician, or someone like him.

Mentioning my having attended The Jim Russell Driving School didn't seem to help the last time. Of course I could go to court and claim discrimination. Although, it didn't work when my brother in law protested to the Judge that he was a victim of discrimination because of the car (RED twin turbo Mitsubishi 3000GT) he drives. The Judge just laughed while pronouncing him guilty.

Would those higher frequencies be of the LASER variety?