Effect of speaker cable on THD

I expect willingness to share information on the internet is related more to the size of the interested audience than it is to success in business.
 
Alan0354 said:
I changed in the two cables I made with the red/black 20 gauge pairs. At the process, I discovered I did my original cables wrong. Yes I use 2 pairs of monster 12 gauge for the mid and tweeter, but before this thread, I did not know the two wires of the cable has to go in pair close together. I use one pair of cable and parallel both conductors together as the red wire and the other cable as the black wire. This result in big loop between the two wires.

I was kind of expect all the talks here in THD might be hot air and it won't make a damn of a difference. Now this is non scientific, just my impression. It sounded very different with the new cable. It's a lot brighter, attack is a lot more apparent, seems to have more air. BUT, I can't say it's better or not, the main reason is I am missing the bottom, it doesn't seems to be balance, it's like I turned the bass down. But I don't have tone control, everything is straight through. Note that I DID NOT change the cable for the woofers, they are still like one cable for red, one cable for black that have bigger area between the two wires. But this is woofer, it shouldn't make much difference.

I can't crank it up as big boss is sleeping already, but it's just lack bottom. I would have to change the preamp a little to make up for the bottom. But to me, it is pretty obvious that the sound is different, more forward, in your face, more attack. The drum comes out more.

I did not expect this, last time when I compare amps, it did not make a damn of a difference, maybe it's because of the cable as it was the same cable. I was expecting no difference, but quite a bit difference.
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Brighter sound points in the direction of higher Levels of interference. Reminds me of quite a few amplifier-builders I`ve seen come and og; they think building amps is all about getting ultralow THD-Levels and get confused when People tells them that their amps do not really play music. Same here, the ultimate test are done by listening. But the strange thing is; wery few tech-guys are good listeners too.
 
unfairlane said:
Brighter sound points in the direction of higher Levels of interference. Reminds me of quite a few amplifier-builders I`ve seen come and og; they think building amps is all about getting ultralow THD-Levels and get confused when People tells them that their amps do not really play music. Same here, the ultimate test are done by listening. But the strange thing is; wery few tech-guys are good listeners too.
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This is not my amp, this is the Nakamichi PA-7 Stasis amp designed by Nelson Pass. I am still building the amp. I don't think his amp is low THD by design. This is straightly comparing cables.

I wrote the post after only a few minutes. After that, I use it to watch tv and more and more, I like it. It just sound closer to me than before like I am more in the middle of it. When things break, it just sounds more real. I still need to test more.
 
The whole thing about mentioning Nelson Pass is on the comment about those exotic cable companies must earn a lot of money. I was just saying otherwise, that even though each sell for a lot of money, I don't think they make a boat load of money as the sales volume is so low. That's what I use Pass as kind of calculation of the earning. Nelson is tremendously successful, I mentioned him numerous times about his innovation and I want to do an amp based on his concept. But here I am talking about straightly business, nothing but business. That I don't think he earn a boat load of money even though he is so successful.

Also we got into my opinion on not willing to pursue even I have a valid good patent because there is no money it in I can see. Just slave labor. Of cause I am interested, more on the innovation, not on the money from the very start. I invested thousands to design and got the patent, but from the get go, I know that was pretty much it. I got my satisfaction and enjoyment. I don't have the "big" dream of earning a boat load of money from that.

Money and passion is a totally different thing. Actually I gone from designing guitar amp and guitar electronics to hifi because I don't enjoy playing guitar anymore, I do spend a lot of time using the hifi for watching tv. So I hung up the music electronics, packed it all up and put it away and start designing power amp. I have no intention of making this into a business, I have only one customer to please.......ME!!!! This is my satisfaction and here I am!!! I paid my dues in my life earning money, I am spending money doing this just for me and that's pretty much it. I don't even plan to make this a life long thing, depends on whether all power amp sounds the same from listening. If they are, I am not going to waste my time designing amps over and over to get the same result!!! I'll just move onto other electronics just like I dropped the guitar electronics cold.
 
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ConradH said:
I know quite a few successful business people and, though outgoing enough in the right circumstance, none of them would be found in any sort of forum or chat.
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They are too busy!!! Successful business implies busy. After a whole day dealing with all the business end of the business, last thing you want to do is to go on a forum talk more about it. When I was working last year, I didn't have time to talk, hell, I did not even have time to work on my amp.

Passion and business is two completely different thing, all my comments are only on the business end and be realistic about it. Also, great idea does not translate to money. In guitar amp, as a seasoned guitarist, the biggest invention of all time is power scaling where you adjust the max output power according to the venue so you get optimal sound at any level. Believe it or not, I came up with this idea before I was even into electronics using a simple Variac from the university chemistry dept to just control the +B and grid bias of the power section, I used separate transformer to power the filaments and preamp. I did it in my Twin Reverb in 1978. Then I quite music, sold the amp and forgot about it. In the mid 90s, London Power got a patent and selling as a kit of power scaling using MOSFET to adjust the +B of the power section and circuit for the grid that track the +B. Idea is exactly the same. Whether you believe me or not is really not important as it's water under the bridge.....way under.....after 40 years. BUT guess what, they really never make it big. Fender, Marshall and Mesa never catch on, never have anything like this. People keep buying them and not too many people I know use power scaling. Why? Who knows!!!! This is just the business end of it, they did not market it right? No body knows. This to me is the greatest invention for guitar amps......going nowhere. This is business for you. Things just look very rosy from outside looking in.

I bet if it's not for Carlos Santana using Mesa Boogie in the 70s, Mesa would be just another long list of boutique amp that a lot of them failed. Same as PRS guitar ( Paul Reed Smith), they got big because Santana featuring this guitar. I know people in a guitar company called Modulus, those are high end guitars, they folded.

Last Christmas, I was doing a duet with my 11 years old grand daughter, she played the piano, I played the guitar on a rock and roll jam. I pulled out my amp to do the jam, the few people commented WOW, sounds like in the club, we were playing are conversation level!!!
 
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I spent some time listening to music. It is definitely brighter, I found myself turning the volume down as the attack is strong when I cranked it up. I was ok with the same volume position before, the attack is just very strong for my ears. It is definitely cleaner, I can hear more stuff that I never realize it's there. But the brightness gets tiring after a while. I wonder whether the 2200pF capacitance affect the Nakamichi amp. I can't wait to put my amp in.

The sound can best described like you go to the gun range without the ear plugs, the first 10 sec, it really doesn't seem very loud, but then your ears start hurting. It's the pressure.
 
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What's your music source? Gotta be careful because the ears can't tell which component is at fault. Ears are also pretty bad at telling which end of the frequency spectrum has an issue. Are things bright because something is wrong with the bass, or is it really bright. I suppose it's all relative, but with all the focus on THD, don't forget to do some system inclusive response measurements, or even pink noise and SA. It seems like, at our age, we have little tolerance for excess brightness, which is exactly opposite what you'd think. I think the green resistor is supposed to arrive here Monday.
 
ConradH said:
What's your music source? Gotta be careful because the ears can't tell which component is at fault. Ears are also pretty bad at telling which end of the frequency spectrum has an issue. Are things bright because something is wrong with the bass, or is it really bright. I suppose it's all relative, but with all the focus on THD, don't forget to do some system inclusive response measurements, or even pink noise and SA. It seems like, at our age, we have little tolerance for excess brightness, which is exactly opposite what you'd think. I think the green resistor is supposed to arrive here Monday.
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Ha ha, I don't even know what you are talking about inclusive response measurements, pink noise and what is SA?

The more I listen, it not brightness, it's the attack, the hard hitting to my ears. For tv, it actually is very good, I watch just tv shows like NCIS, NCIS LA etc. Even though it's not surround sound, it sounds really good as it make it more real and the voice is even closer to me than before.

Also it seems louder than before, I cannot keep the same volume in the test as before. For music, I use the GRP All-Stars Live CD. The drum and the synthesizer just have more attack that it get tiring to my ears after a while and I had to turn down the volume some.

I use the system to watch tv most of the time, it is a lot better, I am not going to change a thing.

Also, I am not using my amp, I have no control in how the Nakamichi PA-7 react to the added capacitance. I measure with the meter that the capacitance of the cable is 2200pF, I don't know whether it is designed for that. Can it be the amp getting touchy?

Too bad the green resistor arrive so late, I was hoping you have the weekend to play with it. The moment you said yes on Monday, I rushed out to UPS and sent it. It was within 1/2 hour after I got your PM!!! I should have gone to USPS instead, they are cheaper and they usually deliver in 3 to 4 days. I just don't want to wait in line and went to UPS instead. I thought at least they'd be as faster as USPS.......NOT!!!
 
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Inclusive just means testing as much of the system as possible- test it the way you use it. In this case I'd probably use Audacity to make a pink noise file and burn it to CD. Play that and do SA- spectrum analysis! See if the system response is what you think it is. You can go one further and use a mic to look at the output where you sit, but that opens another whole can of worms. I'm all talk in this case, as I don't even own a laptop, just a steam powered ancient desktop that can't get to the living room.

Totally OT trivia, but back in the day with tape recorders, you could do a frequency response test with a sine wave and get one thing. Do it with pink noise and you'd likely get another. Can't remember the reason but I think it had something to do with the total signal level on the tape.
 
Can you explain the pink noise thing, I have no idea what it is. What is a SA spectrum analysis. I still yet to learn a lot of the stuffs in audio world.

Ha ha, you really need to get on to the 2000s!!!! You need a laptop, it is so convenient. I have not been using a destop since 2001. I always use a 13" and it follows me wherever I go when I need it. How many times I carry it in a bag and went shopping with my big boss, she can shop and I just find a place to sit and do my own thing. Too bad the tablet is not nearly as powerful enough for me to do all the layout, schematic and simulations, or else I would go to a tablet. I am using a 6th gen I-7 with SSD hard drive and 16G RAM, boot up in 20 sec or less. They are so cheap it's not even funny. My boss still insists on a desktop, I can't even type on that keyboard as I am so used to the smaller keys of the laptop.
 
Spectrum Analysis- SA is the common abbreviation! It's what you're already doing with your THD measurement. It will also show you frequency response if you feed the system a wideband noise signal. Pink noise is a filtered noise signal, but actually I think you just need regular noise- "white noise".

I'm just the opposite, can't type on a laptop to save my life, much less put up with those little finger pad things. Don't know about these days, but I used to be able to hit 60 wpm with a decent keyboard.
 
ConradH said:
Totally OT trivia, but back in the day with tape recorders, you could do a frequency response test with a sine wave and get one thing. Do it with pink noise and you'd likely get another. Can't remember the reason but I think it had something to do with the total signal level on the tape.
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Record equalization. You have to keep record level low enough to prevent tape saturation at high frequencies if you want an accurate frequency response measurement.
 
Alan0354 said:
DIYaudioprojects make something similar, but I would use 18 or 20 gauge. I think twisting should be just as effective. If you don't knit the wires tight enough, it's even worst.

http://diyaudioprojects.com/Power/Low-Inductance-DIY-Speaker-Cables/
This definitely shows people thought about this, about the low inductance, it's nothing new, I never think I am discovering anything new here, Just trying to understand this.....and I sure learn.
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If you want this to perform in your system you`re on the wrong track. Fun begins(!*) at 9awg, take a hint * = low end
 
This is the second time I notice there is a hum sound ( not 60 or 120hz) on the left channel. I turn the amp off and on, the sound disappeared. That's the side I have the 2200pF cable on. I don't think the Nakamichi PA-7 like the cable!!!! I never put the Nakamichi on the bench, I trusted Nelson Pass. Maybe I should actually put it through the ringer like I put my amp through. Also look at the THD.

I have this amp for a year and use it for hours every night, never heard this sound before. I am sure it's not from the house or other devices. I am the only one awake in the house, no one else is turning on anything.
 
Look for parasitic supersonic oscillation at the output with O'scope, compare both channels.
 
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