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maxserg
06-20-2023, 03:14 PM
For those good on maths a question. What would be the delay between two channels if I had 6 feet difference in speaker câble length delay wise and high frequency cancellation?Hope my question is clear!

grumpy
06-20-2023, 05:44 PM
speaker -cable- length difference?
something on the order of 6 nanoseconds.
-not- going to cause any audio cancellation by itself... more likely to cause aesthetic or OCD-type irritation...

speaker -distance- difference?
roughly 10 milliseconds.

delayed room signals (echoes) or bad driver phasing or even damage to some component (as possibilities) could be involved if you're using a mono test signal/noise/music and there's a cancellation when both speakers are on, but not when only one is playing.

grumpy
06-20-2023, 05:47 PM
(full disclosure: it would bother me)

RMC
06-21-2023, 01:46 AM
I think i'm with the new boss here, lol (Grumpy) on this question, though not sure i understand correctly some of his writing.

Looking at the delay aspect from a different perspective than his, here's the thing. The Rolls Digital room/speaker Delay shown has as its shortest delay setting 32 milli seconds which is about equivalent to a 32 feet distance. My understanding is that if a smaller delay than 32ms or 32 ft was really significant in a room the manufacturer would probably have included even smaller delays?

In other words the delay or distance involved might not be large enough to warrant some action to remedy. Naturally i assume that speaker wires used are not undersized creating a resistance issue (level), likewise for a capacitance issue that may create some high frequency rolloff.

I have some high frequency cancellation stuff, from Eargle/Hoge, due to cable length, capacitance, resistance, etc but its more relevant to microphone cables than speaker cables.

Richard

Robh3606
06-21-2023, 05:10 AM
For those good on maths a question. What would be the delay between two channels if I had 6 feet difference in speaker câble length delay wise and high frequency cancellation?Hope my question is clear!

For speaker cable??? Not going to matter. No delay and HF difference simply won't be audible if there is any.

Rob :)

maxserg
06-21-2023, 09:52 AM
Thank for your answers! Yes my question was only about different speakers cable lenght. Assuming that I’m listening exactly at the center, only that there is a 6 feet longer for one side.

grumpy
06-21-2023, 06:08 PM
Boss… that’s funny.
Since the word cancellation was used, not loss or attenuation, I assumed the question was related to two or more sources being heard or measured at one location (this could include echoes from a single source). Not sure if that helps or hurts my feeble explanation of what could have been happening. Hope we helped the questioner :)

More like speed of light in a wire… roughly.

Uncle Paul
06-21-2023, 06:41 PM
IIRC from my tech school days, electricity travels about 90% of the speed of light. That's about 165,000 miles per second or 871,000,000 feet per second (VERY rough numbers). If the long cable ran to the Moon and back that would be an audible three second delay. Even several feet would not induce an audible or likely not measurable delay.

I am certain that a Golden Ear somewhere would hear it, or at least claim to...

Aesthetically, though, it would bug the crap out of me to be even an inch off. Part of my enjoyment is how things look in addition to how they sound. When I make speaker cables I use pants, heat shrink, purdy cable sleeves that cover the word Belden a hundred times and even bright shiny spades that are electrically as effective as the cheapo crimp on ones at home depot.

RMC
06-22-2023, 12:03 AM
Don't worry about boss, was simply a little humour marking your introduction in a new role here as i understand it. Hopefully you'll still have some spare time, in between issues, to visit the crowd as you did here...

The OP's original title was "Speed of sound", later became "Speed of sound... in a wire" as i now see. I was lured by the speed of sound title hence the delay aspect shown, which btw didn't change the fact "I think i'm with the new boss".

The speed of light in a wire also crossed my mind since electricity in a wire isn't in itself speed of sound, but i didn't change my post (the carrots were already cooked).

Richard

toddalin
06-22-2023, 11:27 AM
For those good on maths a question. What would be the delay between two channels if I had 6 feet difference in speaker câble length delay wise and high frequency cancellation?Hope my question is clear!

If you're going to sweat the delay for 6' of speaker cable, you may also want to loose sleep over the difference in wire resistance and capacitance and their effect on the frquency response.

grumpy
06-22-2023, 01:44 PM
"marking your introduction in a new role here as i understand it"

New fearless leader? news to me ... (and not me).

I'm with Uncle Paul though... aesthetically, I want my speaker cables to be the same length.
It just feels better. :)

hjames
06-22-2023, 02:00 PM
I think Grumpy of AudioKarma fame (the so-called "new Boss" ??) is different than our Grumpy here on Lansing Heritage ...



"marking your introduction in a new role here as i understand it"

New fearless leader? news to me ... (and not me).

I'm with Uncle Paul though... aesthetically, I want my speaker cables to be the same length.
It just feels better. :)

maxserg
06-22-2023, 02:40 PM
That story came from one person who claim that would be phase différence for on the side with 6 Moore feet longer! I told him no difference! But he continued to argue…So thanks guys for your answers and… humor!😁

grumpy
06-22-2023, 08:10 PM
I think Grumpy of AudioKarma fame (the so-called "new Boss" ??) is different than our Grumpy here on Lansing Heritage ...

Ah. Makes sense. Haven't experienced that mixup for many years... but enough of that. Congrats/condolences to whomever is willing to herd the cats.

toddalin
06-23-2023, 11:15 AM
Ah. Makes sense. Haven't experienced that mixup for many years... but enough of that. Congrats/condolences to whomever is willing to herd the cats.

Easy mistake and one I made when first joining AudioKarma. Did you ever finish those nice furniture-grade, 18" cabinets from San Diego?

Ian Mackenzie
06-24-2023, 04:13 PM
The problem arises with snake oil hifi loudspeaker cables that may introduce capacitive and inductive loading of the power amplifier output stage and negative feedback loop. If the cable length is sufficiently different the impact on each channel may be different. This type of situation can effect the stability of the amplifiers. The best cables are short and stout.

A nerd on strong meds will always claim to hear differences in loudspeaker cable lengths. They even resort to placing cables on expensive supports to keep the cable off the floor. A visit to a doctor would find the nerd’s ears completely block with wax!

maxserg
07-12-2023, 03:28 PM
The problem arises with snake oil hifi loudspeaker cables that may introduce capacitive and inductive loading of the power amplifier output stage and negative feedback loop. If the cable length is sufficiently different the impact on each channel may be different. This type of situation can effect the stability of the amplifiers. The best cables are short and stout. A nerd on strong meds will always claim to hear differences in loudspeaker cable lengths. They even resort to placing cables on expensive supports to keep the cable off the floor. A visit to a doctor would find the nerd’s ears completely block with wax!Ha ha ha! I strongly agree! And like your sense of humour!

Ian Mackenzie
07-12-2023, 05:39 PM
On one occasion when l met Nelson Pass he said you do know it (hifi equipment) is the entertainment industry.

But l like if because it’s fun hobby that brings much joy. The only issue is an empty wallet.

In the diy space you have the advantage of flexibility with how you want your system to sound and at far lower cost than consumer hifi equipment.

The only thing l’ve bought in the last 15 years is VPI Turntable, a streamer and a Parasound preamp and power amp. I’ve since sold the preamp and the streamer after l acquired a JBL Synthesis dsp 58 processor. With that l can minimum a few acoustic issues and very precisely adjust the tonal balance to my liking without resorting to snake oil solutions.