Why aren't speaker cables Coaxial?

[Stupid_Ben]

Just out of interest I was wondering and couldn't work out...

Why are (even high-end) speaker cables not coaxial? We always use a coaxial cable in the lab to get rid of the noise on our measurements.

I figure that 50/75 ohm standard coax would create an impedance mismatch with the typically low ohmic speakers and output of the audio amplifier. However, I calculate that with an outer diameter to inner diameter radius of 1.1, the impedance would be 2.5 Ohms as per below $Z_0 =\frac{138\Omega}{\epsilon_r}log_{10}(1.1)=2.5 \Omega$$\epsilon_r=2.33$ which I think is typical.This ratio seems feasible to me, to be made into a thin flexible wire.

Come to think of it my guitar cable is coax, and so are some headphones cables.look forward to hearing your comments on this.

Ben

 

[Studiot]

Good afternoon Ben.

I can explain coaxial speak cables a bit.

Noise is only a problem if its level is comparable to that of the signal. This is measured by the parameter 'signal to noise ratio'.

Since the noise in a given situation is pretty fixed the only variable is the signal level.

Thus noise is only significant for low-level signals like microphones and pickups.

For signals at loudspeaker levels, the noise becomes an insignificant proportion of the total signal.
go well

 

[Stupid_Ben]

Thanks Studiot I hadn't thought about that. I guess speakers need a fair amount of signal to get them to move!

Hence the excuse behind the enormousness speaker wires audio buffs spend vast sums of money on.

 

[yungman]

Also coax has shunt capacitance also. As small as it is, still in the range of 50 to 100 pF. Not to mention it would be very stiff.

The important thing about speaker cable is the size of the conductor. I am into audiophile, I actually experiment with speaker cables. I ended up using 4 pairs of 12 gauge Monster type of cable for each speaker. I add one pair at a time and amazingly it make a difference in the sound.

Small little capacitance at audio freq don't seems to be important, so are 2 pair or 4 pair of those big cables! I ended up spending close to $1000 on all the inter connects in my stereo system and they are not of top quality. Human ears are funny! It is not about the highs and the lows of the sound, it open up the perceived sound stage. It make the sound more three dimensional and more airy.

 

[f95toli]

The answer is actually a bit subtler than that. Which type of cable is best depends on the source and load impedance. For situations where you are primarily interested in the "current" (low impedances) one should -in general- use twisted pairs; whereas in high(ish) impedance ("voltage") situations (and at high frequencies) coax is better.
Note that microphone cables are also (usually) twisted pairs.


Note that this does not only apply to speakers (or audio). In the lab one should use a mixture of twisted pairs (preferably shielded) and coaxial cables; depending on the application (hence, if you are ONLY using coaxial cables in your lab, you are either working with high impedances or you are doing something wrong).

There are also all sorts of ifs and buts to this; which is one reason why there are also other types of cables (notably triax).

 

[Stupid_Ben]

Hi yungman,

Thanks for the interesting comment, I can't say I every actually tried playing with big cables but it is interesting to know that you find it makes a difference. I think that the highs and low frequencies make the harmonics and resonances which makes a sounds "open up " . Though I imagine that it less down to transmission of specific frequencies, more to do with a temporal response perhaps... BTW just out of interest did you try a blind test? the 'placebo effect' can be very strong

 

[Stupid_Ben]

Hi f95toli,

I think I agree with you on most things. However one 'but' that I think might be worth mentioning . For low frequency, the characteristic impedance of coax makes no difference, but it's shielding is much better than twisted pair. That's why we like to use it, also it radiates much less than twisted pair at high frequencies.If I'm wrong please tell me !

 

[f95toli]

Hi f95toli,

but it's shielding is much better than twisted pair. That's why we like to use it, also it radiates much less than twisted pair at high frequencies.

No, its not. It really depends on what kind of interference you are trying to shield from (inductive/capacitive pickup, RF interference etc). Also, for low-level signals one should of course use shielded twisted pairs (grounded at one or both ends, depending on the situation). Coax would be pretty useless if one was for example to try to do a simple 4-point resistance measurement of a low-ohmic load (a pretty common thing to do).

See e.g. Ott's "Noise Reduction Techniques in Electronic Systems" or a similar textbook.

But, yes. For high frequencies one would generally speaking use coax (but not always, network cables are twisted pairs).

 

[Stupid_Ben]

I don't remember ever having seen shielded twisted pair...

Anyway I'll have a look at the book you recommend next time I'm at work.

 

[Studiot]

whereas in high(ish) impedance ("voltage") situations (and at high frequencies) coax is better.

50 ohms or less coax is high impedance?

Whereas 'figure of eight' or ribbon is 300 ohms.

 

[f95toli]

I don't remember ever having seen shielded twisted pair...

Shielded twisted pairs are very common. Standard LAN (network) cable is a good example; shielded CAT5e is very common (contains 4 pairs in a foil shield)

 

[skeptic2]

I am into audiophile, I actually experiment with speaker cables. I ended up using 4 pairs of 12 gauge Monster type of cable for each speaker. I add one pair at a time and amazingly it make a difference in the sound.

Small little capacitance at audio freq don't seems to be important, so are 2 pair or 4 pair of those big cables! I ended up spending close to $1000 on all the inter connects in my stereo system and they are not of top quality. Human ears are funny! It is not about the highs and the lows of the sound, it open up the perceived sound stage. It make the sound more three dimensional and more airy.

I have always been curious about this and I wonder if you've ever done any blind testing. What kinds of sounds is it most noticeable with? How much power are you delivering to the speakers? Which characteristics of the monster cables do you think are responsible for the difference in sound, less resistance, less inductance or what? Don't the wires inside the speaker cabinet from the terminals to the speaker itself have enough resistance and inductance to nullify the effect of monster cables?

As you refer to cable pairs, I assume you have a stereo system rather than a 4 channel system. Since stereo and our ears are at best a two dimensional system, how is the third dimension perceived?

 

[f95toli]

50 ohms or less coax is high impedance?

Whereas 'figure of eight' or ribbon is 300 ohms.

I was referring to the impedance of the source/load; the cable impedance is more or less irrelevant unless you are measuring at high freqiencies (although the cable capacitance/inductance can matter, so the impedance has an indirect effect).
And yes, 50 ohm is a high(ish) impedance in many situations.

 

[Studiot]

No of course the cable impedance is not irrelevant.

For the record.

The standards for audio and telephone work are set at 600 ohms

Most coaxial laboratory instrumentation uses 50 ohms, as does computer coaxial connections.

Radio (including TV) uses 75 or 150 or 300 ohms.

In all cases it is important to ensure the cable and loads are matched to avoid reflections.

 

[f95toli]

In all cases it is important to ensure the cable and loads are matched to avoid reflections.

But reflections are only an issue if your measuring at a frequncy where the wavelength is of the same order of magnitude (say lambda/4) as the length of the cables. In the lab this is usually only an issue RF/MW measurements (over say 10 MHz). It is complettely irrelevant if you are for example measuring a reistance with a multimeter.
Low-noise measurements are much, much trickier near DC than at high frequencies.

 

[yungman]

Hi yungman,

Thanks for the interesting comment, I can't say I every actually tried playing with big cables but it is interesting to know that you find it makes a difference. I think that the highs and low frequencies make the harmonics and resonances which makes a sounds "open up " . Though I imagine that it less down to transmission of specific frequencies, more to do with a temporal response perhaps... BTW just out of interest did you try a blind test? the 'placebo effect' can be very strong

I was doing the test together with my wife. It was quite obvious. Believe me, I was a absolute non believer before. The reason I even tried this was because I bought a pair of JM Lab to replace the pair of Kef and I did not hear any significant improvement and I was getting desperate and looked into it. The better the quality the system, the more critical it is. Yes we went back a fore to verify.

I was absolutely surprised.

 

[AlephZero]

If anybody can give a rational scientific explanation as to what is so good about speaker cable that costs $1000 per meter, and which must for best performance be connected "the right way round" (it is marked to show which end to connect to the amp and which end to the speakers), go right ahead.

Personally, I find flat 30-amp mains power cable works just fine. I don't really need more power than 1800 watts per speaker in my house, so I'm not going to exceed the rating of the cable!

Cheap and nasty connectors with high and/or inconsistent internal resistance are a differnet matter. Fractions of an ohm are significant for high power low impedance wiring like loudspeakers. But copper wire is just copper wire, whether it comes from your local electrical store or insulated with snake oil and costing 10,000 times as much, IMHO.

 

[AlephZero]

The standards for audio and telephone work are set at 600 ohms

That has no relevance to speaker cables.

Why would you want to connect an amplifier with an output impedance of say 0.01 ohms (if it's a good quality amp) to a speaker with nominal impedance 4 ohms, with a 600 ohm impedance cable?

 

[Studiot]

That has no relevance to speaker cables.

Why would you want to connect an amplifier with an output impedance of say 0.01 ohms (if it's a good quality amp) to a speaker with nominal impedance 4 ohms, with a 600 ohm impedance cable?

Have you ever heard of 100V line audio distribution systems?

 

[skeptic2]

I was doing the test together with my wife. It was quite obvious. Believe me, I was a absolute non believer before. The reason I even tried this was because I bought a pair of JM Lab to replace the pair of Kef and I did not hear any significant improvement and I was getting desperate and looked into it. The better the quality the system, the more critical it is. Yes we went back a fore to verify.

I was absolutely surprised.

How long are your speaker cables? Have you checked the size wire used inside the speaker cabinet? Do your speakers have crossover networks? I was about to consider that an extremely low source impedance may have a damping effect on the speaker but wondered if the internal wiring of the speaker, including the crossover network provide enough impedance to negate any effect a low output impedance amp and low resistance wires might provide.

Have you ever driven your speakers with a square wave to see how much overshoot and ringing you have?

 

[gnurf]

If anybody can give a rational scientific explanation as to what is so good about speaker cable that costs $1000 per meter, and which must for best performance be connected "the right way round" (it is marked to show which end to connect to the amp and which end to the speakers), go right ahead.

Feels like I'm beating on a dead horse here, but I had to look up this directional audio (i.e., AC signals -- should be obvious why the cable can't be directional!) cable nonsense. FWIW, this is from the FAQ of one of the most well-known manufacturers of such cables:

Q: Will I notice a difference if I hook up my cables in the wrong direction?
A: You probably will not, but if you think that you are experiencing noise problems, check that they are. Cables are directional for shielding purposes only. Should you not see these arrows, remember that the signal flow should go in the same direction of the print on the cable jacket, reading left to right away from the source (source to destination)

Q: Why do the cables have directional arrows?
A: This is done for shielding purposes only, a design where we do not solder the shield on the signal's destination. This ensures that any noise picked up by the shield will not be transmitted into your signal path.

I was doing the test together with my wife. It was quite obvious. Believe me, I was a absolute non believer before. The reason I even tried this was because I bought a pair of JM Lab to replace the pair of Kef and I did not hear any significant improvement and I was getting desperate and looked into it. The better the quality the system, the more critical it is. Yes we went back a fore to verify.

I was absolutely surprised.

Yungman, the test you did with your wife produces very little valuable information IMO. As an absolute minimum, you should do a blind test where--among many other cognitive biases--the emotional pain of having wasted a lot of money on cheap copper wire is not allowed to impair your judgment. And you're also testing cables, interconnects and everything else in between your source and destination at the same time, so how do you know what contributed to what?

EDIT: I'm not sure it matters much though whether or not you can prove objectively that one cable is better than another, since the listening experience is subjective in any case (i.e. you'll bring your personal biases to the table every time you use the system). But surely this topic has been discussed to death already so I probably haven't added anything new here!

 

[yungman]

I have always been curious about this and I wonder if you've ever done any blind testing. What kinds of sounds is it most noticeable with? How much power are you delivering to the speakers? Which characteristics of the monster cables do you think are responsible for the difference in sound, less resistance, less inductance or what? Don't the wires inside the speaker cabinet from the terminals to the speaker itself have enough resistance and inductance to nullify the effect of monster cables?

As you refer to cable pairs, I assume you have a stereo system rather than a 4 channel system. Since stereo and our ears are at best a two dimensional system, how is the third dimension perceived?

Actually this got me thinking this morning. I did the experiment in 97 when I first bought my speakers. I did not do a blind test, it was very obvious for the first two pairs of 12 gauge. When I said 4 pairs, I meant 4 pairs of 12 gauge for EACH speaker! !

Now I have been studying EM, I just did a calculation of the skin effect at 10KHz:

$$\delta=\frac 1 {\sqrt{\pi f \mu \sigma}} =\frac 1 {\sqrt{3.14\times 10^4\times 4\pi\times 10^{-7}\times 5.8\times 10^7}}=6.6\times 10^{-4}m$$

As you can see, the current is not evenly distributed in the cable, most are still on the surface. So up to a certain point, the size of a single cable is not as important as the surface area of the conductor.

I don't think you can quantify with just by the highs and the base of the sound. When the quality of the system is at certain standard, it is more the perceived sound stage and the three dimension quality of the system. You cannot really hear the high frequency, but you can feel it, the sharp attack of the sound. It is like if you put the tv sound into the system, every time the door open or the phone rings, you turn around thinking that's your phone or the door.

I had surround sound, but I no longer hook it up because it never sound as good as stereo.

Regarding to the volume, you'll notice a not as good system only sound good when you crank to volume up. A good system sound good in low volume. This is very noticeable. I don't even turn the volume up. I double the average power is more than a watt or so, the instantaneous power might be high, that's why you need a good power amp.

 

[yungman]

How long are your speaker cables? Have you checked the size wire used inside the speaker cabinet? Do your speakers have crossover networks? I was about to consider that an extremely low source impedance may have a damping effect on the speaker but wondered if the internal wiring of the speaker, including the crossover network provide enough impedance to negate any effect a low output impedance amp and low resistance wires might provide.

Have you ever driven your speakers with a square wave to see how much overshoot and ringing you have?

All my speakers have cross over. I never touch the JM Lab, but I did experiment with the Kef. I really beef up one speaker I even put big wires parallel with the pcb trace in the cross over network. I compare with the other one, it only make little difference. Not even close to the difference with the external cable.

The JM Lab and the true high end speakers have separate input for the woofer and the mid/treble speakers. So they beef up by default. I use two pair of 12 gauge to drive the woofer, two pairs to drive the mid/treble speakers. I don't think it make as much difference on the woofer, it's the mid/high that is more critical.

 

[yungman]

Feels like I'm beating on a dead horse here, but I had to look up this directional audio (i.e., AC signals -- should be obvious why the cable can't be directional!) cable nonsense. FWIW, this is from the FAQ of one of the most well-known manufacturers of such cables:

Q: Will I notice a difference if I hook up my cables in the wrong direction?
A: You probably will not, but if you think that you are experiencing noise problems, check that they are. Cables are directional for shielding purposes only. Should you not see these arrows, remember that the signal flow should go in the same direction of the print on the cable jacket, reading left to right away from the source (source to destination)

Q: Why do the cables have directional arrows?
A: This is done for shielding purposes only, a design where we do not solder the shield on the signal's destination. This ensures that any noise picked up by the shield will not be transmitted into your signal path.Yungman, the test you did with your wife produces very little valuable information IMO. As an absolute minimum, you should do a blind test where--among many other cognitive biases--the emotional pain of having wasted a lot of money on cheap copper wire is not allowed to impair your judgment. And you're also testing cables, interconnects and everything else in between your source and destination at the same time, so how do you know what contributed to what?

EDIT: I'm not sure it matters much though whether or not you can prove objectively that one cable is better than another, since the listening experience is subjective in any case (i.e. you'll bring your personal biases to the table every time you use the system). But surely this topic has been discussed to death already so I probably haven't added anything new here!

Do you have a good pair of speaker to try before? If you speaker is under $1000 a pair, I don't think you need to worry about this. I am talking about $5000+ a pair.

I am actually very skeptical about all this, it made a believer out of me. Value or no value is in the ear of the beholder. I don't even buy the uni-direction thing as I did compare and don't hear the difference. BUT I do know in RF pcb layout, we do specify the direction of the copper cladding. The difference between one pair and two pairs are so distinct that I never thought of blind test. I stopped at 4 pairs because I don't notice much difference between 3 pairs and 4 pairs. Psychosomatic never work on me particularly if I don't believe it and I never did until that time. I still don't believe in buying expensive cables, I just bough 12 gauge speaker cables from hardware store, the ones that has very fine strands. I don't even believe in buy expensive cable from audiophile store.

Maybe if I buy a pair of $20K+ speaker, I might buy into the more expensive stuff, for now, the more cable the better.

 

[yungman]

How long are your speaker cables? Have you checked the size wire used inside the speaker cabinet? Do your speakers have crossover networks? I was about to consider that an extremely low source impedance may have a damping effect on the speaker but wondered if the internal wiring of the speaker, including the crossover network provide enough impedance to negate any effect a low output impedance amp and low resistance wires might provide.

Have you ever driven your speakers with a square wave to see how much overshoot and ringing you have?

One side is about 10 feet, the other side is about 5 feet. I would make it shorter if I could at the time. No, I never test with square wave.

There is still some black magic in audiophile and guitar amps that I don't quite understand. Human ears are more sensitive than any of the instruments. You can never explain why some of the extreme high end tube power amp is less than 5W single end tube only, brands like Cary. A lot of the high end power amp are still using tubes.

You would think two power amp with the same rated power should be very close since they are all electronics and if you can make it to same minimal distortion, they should not be to far apart! They are a world apart. This is another subject all together. My favorite amp is a European brand call YBL. I am just too cheap as I made the mistake of buying one that match the Kef and then I bought the JM Lab. I am too cheap to put the Acurus aside and buy that. In fact, the YBL was only 70W per side and the Acurus is 200W per side.

 

[Studiot]

I don't think you can quantify with just by the highs and the base of the sound. When the quality of the system is at certain standard, it is more the perceived sound stage and the three dimension quality of the system. You cannot really hear the high frequency, but you can feel it, the sharp attack of the sound. It is like if you put the tv sound into the system, every time the door open or the phone rings, you turn around thinking that's your phone or the door.

I had surround sound, but I no longer hook it up because it never sound as good as stereo.

Regarding to the volume, you'll notice a not as good system only sound good when you crank to volume up. A good system sound good in low volume. This is very noticeable. I don't even turn the volume up. I double the average power is more than a watt or so, the instantaneous power might be high, that's why you need a good power amp.

I would support all these comments from personal experience and would be happy to discuss it further but this is really off topic for this thread. By all means start another.

go well

 

[Stupid_Ben]

Are the cat5 cables twisted pair because it's cheap? or is it for their low impedance?

I thought that 50 ohm coax was good choice for attenuation and usability at high frequency

 

[yungman]

Are the cat5 cables twisted pair because it's cheap? or is it for their low impedance?

I thought that 50 ohm coax was good choice for attenuation and usability at high frequency

That is a totally different topic. Cat5 is twisted pair, that is for common mode noise cancelling. It is not as good as coax as a transmission line for really high frequency but for 100MHz, it seems to work as proofed by Ethernet.

Of cause it is mostly about money! Although twisted pair could be better in common mode rejection.

 

[yungman]

If anybody can give a rational scientific explanation as to what is so good about speaker cable that costs $1000 per meter, and which must for best performance be connected "the right way round" (it is marked to show which end to connect to the amp and which end to the speakers), go right ahead.

Personally, I find flat 30-amp mains power cable works just fine. I don't really need more power than 1800 watts per speaker in my house, so I'm not going to exceed the rating of the cable!

Cheap and nasty connectors with high and/or inconsistent internal resistance are a differnet matter. Fractions of an ohm are significant for high power low impedance wiring like loudspeakers. But copper wire is just copper wire, whether it comes from your local electrical store or insulated with snake oil and costing 10,000 times as much, IMHO.

I don't buy into the very expensive cable either. But from the skin effect calculation, above 10KHz, the dept get quite thin, so I do believe more pairs of cable with fine strands give you more surface area. This no only lower the resistance, the most important thing ( just my thinking only) is the inductance of the cable. A little increase of inductance might change the phase and attenuation of the highs. Even though ears cannot hear about 10KHz to 15KHz, but I do believe your body feel it. Again, I believe it's the transient that made the sound real.

I believe the hardest sound to produce is glass breaking, crashing of the symbol of the drummer in music, object drops, explosion etc. All these have very sharp transient and very large dynamic range. No matter how good the system, I don't think any recording can come close to capturing these sounds. That is the reason you always can tell a live band out of the recording, and the most obvious is the percussion including drums. To a less degree, sax and other horn instrument. The true sound has the kind of raw edge that the recording cannot produce. Those are the sound that the better the system, the more you get out of it and the more critical the inter-connects are.

I did try reverse those uni-directional coax, and I cannot tell the difference in my system, my system is no where belong to the top end, so I am not going to say yes or no. Again, this is only my theory and I am no expert. None of these can be measure by instruments as human ears are much sharper than the instruments.

 

[yungman]

In the subject of believability of all the fancy stuff, I am going to change the subject.

Electric guitar and amplifier electronics is another field that have all sort of strange believes just like audiophile. I might have a chance of working with a guitar pickup manufacturer. Depend on the negotiation, I might design a little of the preamp electronics. I really go to challenge their conventional believe.

They believe:

1) Metal film resistor do not sound good.
2) The op amp has to be MC4558 or even a certain brand.
3) Has to be a certain orange tear drop capacitor in the signal path.

Just to name a few. One famous guitarist Eric Johnson believe he can hear the difference in what kind of 9V battery used. .

I am going to use 1% metal film resistors, using ON-Semi MC33179 op-amp, I am going to use the cheapest ( ceramic) capacitors. I am going to have pull down resistor to make the output stage into class A ( only the NPN work all the time). I am not going to say anything and let them listen and see what happen.

I don't buy into any of this!

 

[skeptic2]

I don't buy into the very expensive cable either. But from the skin effect calculation, above 10KHz, the dept get quite thin, so I do believe more pairs of cable with fine strands give you more surface area. This no only lower the resistance, the most important thing ( just my thinking only) is the inductance of the cable. A little increase of inductance might change the phase and attenuation of the highs. Even though ears cannot hear about 10KHz to 15KHz, but I do believe your body feel it. Again, I believe it's the transient that made the sound real.

The resistance for 1 strand of 12 AWG wire 10 feet long is 0.01588 ohms. Four pairs would bring that down to about 8 milliohms round trip. If your receiver has an output impedance of about 10 milliohms, that amount of resistance sounds about right. What I am concerned about however is the crossover network of the speaker itself. I find it difficult to imagine a crossover network that can transform 20 milliohms to 4 ohms and at the same time maintain a relatively constant source impedance and phase over the full range of each speaker. Also for a high end speaker we would not want to alter the original phase relationship between the low medium and high frequencies. I think a crossover network that fails to do all of the above would mask and negate any benefit of low resistance cables. It also seems to me audiophiles should be putting much more attention to the design of the crossover network than to the resistance of the cables.

I believe the hardest sound to produce is glass breaking, crashing of the symbol of the drummer in music, object drops, explosion etc. All these have very sharp transient and very large dynamic range. No matter how good the system, I don't think any recording can come close to capturing these sounds. That is the reason you always can tell a live band out of the recording, and the most obvious is the percussion including drums. To a less degree, sax and other horn instrument. The true sound has the kind of raw edge that the recording cannot produce. Those are the sound that the better the system, the more you get out of it and the more critical the inter-connects are.

This sounds reasonable. In fact I've heard that the attack of a piano note must be clipped in digital recordings because there is not enough dynamic range to capture both that peak and the soft passages.

I did try reverse those uni-directional coax, and I cannot tell the difference in my system, my system is no where belong to the top end, so I am not going to say yes or no. Again, this is only my theory and I am no expert. None of these can be measure by instruments as human ears are much sharper than the instruments.

The problem is the human mind often compensates for deficiencies in speakers and ears.

 

[yungman]

The resistance for 1 strand of 12 AWG wire 10 feet long is 0.01588 ohms. Four pairs would bring that down to about 8 milliohms round trip. If your receiver has an output impedance of about 10 milliohms, that amount of resistance sounds about right. What I am concerned about however is the crossover network of the speaker itself. I find it difficult to imagine a crossover network that can transform 20 milliohms to 4 ohms and at the same time maintain a relatively constant source impedance and phase over the full range of each speaker. Also for a high end speaker we would not want to alter the original phase relationship between the low medium and high frequencies. I think a crossover network that fails to do all of the above would mask and negate any benefit of low resistance cables. It also seems to me audiophiles should be putting much more attention to the design of the crossover network than to the resistance of the cables.


This sounds reasonable. In fact I've heard that the attack of a piano note must be clipped in digital recordings because there is not enough dynamic range to capture both that peak and the soft passages.


The problem is the human mind often compensates for deficiencies in speakers and ears.

I don't have enough experience with crossover network, I don't even dare to touch it. My feeling is the low pass crossover side is no where as critical compare the mid and the tweeter side. I think they really need good capacitors...which I still don't quite buy into yet. I still believe if you need a 10uF, instead of pulling hair to get the best one, use two 4.7uF, one 0.47, one 0.1 high voltage cap ( like 200V that has bigger area and thicker dielectric) to make up the 10uF. This combination should have very low ESR.

Actually I think one of the biggest path of the electronics that contribute to the loss of fidelity is the mic that record the sound! It is just like speakers, nothing is linear about it and the dynamic range is limited also. So far we never talked about human voice. This is because when we listen to concert, singer sing through the mic, what you hear already include the distortion already. Just listen to a person singing without a mic, it is not even close to the voice through the PA system.

 

[jim hardy]

our mind will color our perceptions in accordance with our pride and prejudices...


given that today's speaker standards specify DC resistance of speaker coil to be around 80% 0f nominal z,

ie an 8 ohm speaker has about 6 ohms of resistance

i could never buy into necessity of exotic wire for connecting to them.
so i am skeptical...

but i do relish hearing of you guys' experiments.

I never owned more than 100 watts
and never used anything larger than #16 copper lamp cord.
i believe sound is mostly in quality of magnet structure and cone material.
Enclosure too, of course.

the ear hears via electrochemistry of nerves in the cochlea and i just don't see how that could be sensitive to phase.

carry on, fellows, i am very interested.

old jim

 

[yungman]

our mind will color our perceptions in accordance with our pride and prejudices...


given that today's speaker standards specify DC resistance of speaker coil to be around 80% 0f nominal z,

ie an 8 ohm speaker has about 6 ohms of resistance

i could never buy into necessity of exotic wire for connecting to them.
so i am skeptical...

but i do relish hearing of you guys' experiments.

I never owned more than 100 watts
and never used anything larger than #16 copper lamp cord.
i believe sound is mostly in quality of magnet structure and cone material.
Enclosure too, of course.

the ear hears via electrochemistry of nerves in the cochlea and i just don't see how that could be sensitive to phase.

carry on, fellows, i am very interested.

old jim

Use cheap #12 multi strands, you might be surprised. It is not much more than the #16 in the big picture. You don't need any fancy stuff.

 

[jim hardy]

i think i'll give that a try.

i always speculated that part of this long standing debate lies in transfer function of amplifiers.
modern stereo uses feedback to make a closed loop controlling the voltage across load

whereas in old days the pentode output stage was a controlled current source, (think Norton)
so compared to a modern amp, voltage across load was comparatively free to be the differential of applied current .

I guess your speaker wire impedance is one more term in system transfer function?
It lies in between amp and the speaker's inductance/inertia so is outside the feedback loop..

might that help explain an unexpected sensitivity?
We need Morbius.

old jim