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Author Topic: Alpha Dog Prime - Stream of Consciousness and Eventual Measurements  (Read 16283 times)

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CCS

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #130 on: April 19, 2015, 02:14:38 AM »

What's the relevant calculation to get %distortion from the difference between its level and the frequency in question? That spike is absolutely unreal for a $1k headphone.
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Marvey

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #131 on: April 19, 2015, 02:20:35 AM »

-25db down from the fundamental is about 5-6% - this is at the spike.
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CCS

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #132 on: April 19, 2015, 02:32:40 AM »

Oh, Jesus. I'll have to look up the math for that, so that I can do those calculations for myself when nobody is around to give me the answer, but that puts things into perspective. Over 5% is madness. I don't know if that's just another defective pair, or if all units are going to have some poor distortion figures, but I certainly don't think the Alpha Prime will ever be a part of my desktop rig.
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Hands

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #133 on: April 19, 2015, 03:15:09 AM »

Or just use this site: http://www.sengpielaudio.com/calculator-thd.htm

Looks better and worse in some regards. And this is a good pair?
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No_One411

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #134 on: April 19, 2015, 03:18:00 AM »

Marv, that 2nd pair is my pair right, and not Bill's?

I suppose you can preface that with...all Asians look alike.
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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #135 on: April 19, 2015, 03:40:26 AM »

Alright, I made some time to read this thread.

So - measurements and QC issues aside - has anyone (considered relatively reliable by the membership herein) heard the Alpha Primes and considered them a further improvement over the Alpha Dogs ?
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Marvey

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #136 on: April 19, 2015, 03:56:17 AM »

Marv, that 2nd pair is my pair right, and not Bill's?

I suppose you can preface that with...all Asians look alike.

lol. people keep sending me stuff. hard to keep track.


P.S. I did fiddle quite a bit to get both sides to match up as close to possible. The Primes are sensitive to positioning. I picked the best L and R results that matched the best. Took several measurements which involved complete removal of the headphone and placement back on the C.U.N.T.
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riker1384

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #137 on: April 19, 2015, 04:09:32 AM »

-25db down from the fundamental is about 5-6% - this is at the spike.

I don't understand this. Every 10db is a factor of ten, right? So -25db should be 1/(10^2.5) = 0.00316 = 0.316%, right?

What am I missing? Apparently you're taking the square root of (10^2.5) for some reason.
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Marvey

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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #138 on: April 19, 2015, 04:25:43 AM »


      db = 20 x log(distperc/100)

distperc = 10 ^ ( db/20) x 100

           10 ^ (-25/20) x 100 = 5.6234
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Re: Alpha Dog Primes - Stream of Consciousness and Eventual Measurements
« Reply #139 on: April 19, 2015, 04:34:22 AM »

I don't understand this. Every 10db is a factor of ten, right? So -25db should be 1/(10^2.5) = 0.00316 = 0.316%, right?

What am I missing? Apparently you're taking the square root of (10^2.5) for some reason.


You're thinking power. Factor of ten for voltage (SPL) is 20dB

Alright, I made some time to read this thread.

So - measurements and QC issues aside - has anyone (considered relatively reliable by the membership herein) heard the Alpha Primes and considered them a further improvement over the Alpha Dogs ?

Simply put, no
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