dpump
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Is there any reason I can't use a 3-amp 17-volt torodial transformer on my Modi 2 Uber? I know the instructions say don't use any other power supply...
Schiit Happened: The Story of the World's Most Improbable Start-Up
- Thread starter Jason Stoddard
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Is there any reason I can't use a 3-amp 17-volt torodial transformer on my Modi 2 Uber? I know the instructions say don't use any other power supply...
jcx
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no in house EMC testing for pre qual? - or do you just send it all out, rent time at a test facility?
I would want (actually have) a 2 GHz spectrum analyzer for any modern digital work with 100 MHz+ DSP, FPGA - used HP/Agilent and new USB/PC based are cheapish today
seems easier to get equipment now that I'm retired and can just buy it
amplifier feedback loop gain/phase measurement really needs a Vector Network Analyzer if you are serious - most engineers I've seen do just use indirect eyeball judgments of overshoot, ringing response of the closed loop combined with worst case design
I would want (actually have) a 2 GHz spectrum analyzer for any modern digital work with 100 MHz+ DSP, FPGA - used HP/Agilent and new USB/PC based are cheapish today
seems easier to get equipment now that I'm retired and can just buy it
amplifier feedback loop gain/phase measurement really needs a Vector Network Analyzer if you are serious - most engineers I've seen do just use indirect eyeball judgments of overshoot, ringing response of the closed loop combined with worst case design
superjawes
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The trick with measurements and numbers in general is that they actually have to mean something. Anyone can pull statistics shaped to an agenda...
As for the "realm of the unknown" or "magic" measurements, I really think that comes down to test bench versus real world. Heck, we're taught that lab tests should only handle one variable at a time, and that reflects the "one signal per measurement" methods. In application, we KNOW that the input is going to be very different. The multi-tone test is still somewhat clinical, but it is a better representation of how something will actually perform.
I guess I am saying "thank you" for doing the listening test to keep everything grounded in reality
As for the "realm of the unknown" or "magic" measurements, I really think that comes down to test bench versus real world. Heck, we're taught that lab tests should only handle one variable at a time, and that reflects the "one signal per measurement" methods. In application, we KNOW that the input is going to be very different. The multi-tone test is still somewhat clinical, but it is a better representation of how something will actually perform.
I guess I am saying "thank you" for doing the listening test to keep everything grounded in reality
kongmw
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i dream of owning a work bench stocked with one of every testing instruments Jason listed, so i could do...
uhhhh.. ummmm...
not sure what i could do
uhhhh.. ummmm...
not sure what i could do
3 toes of fury
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Jason,
Ive said it before and i'll say it again...THANK YOU. Thank you for taking the time to write these chapters and share them with we head-fi-fans. Chapters like this one are a special treat as Im sure Im not alone in being a huge headphone/Amp/DAC fan who's always wanting to learn more about the....well, i'll call them the "ThreeToesofFury Four T's of Interest"....Technology, Terminology, Testing, and Totally-Tubular-Geeky-Info. (Had to shoehorn that fourth one in there...buuuut it seems to fit the bill...especially for fans of 80s new wave music..wink wink nudge nudge).
I am really impressed...and honestly a little vexed at times...by your willingness to share so much detail of what happens in the land o Schiit. As one who works within a technology based industry, i find that information hording is far more prevalent than information sharing...even within a company. The fact that you share so much, so freely, with such a positive attitude and approach, is a testimony to who you are and the company you run. Its one of the reasons I plan on remaining a life long Schiit customer. (Well, also because every Schiit product ive bought has blown me each time and
made such a difference in the music i listen too....Dats da fact jack!).
Keep up the great work and great writing dude. There's alot of us out here who love it. (And i think our ranks our growing...I.T. came by to fix my phone yesterday and asked about my Magni2U amp...by the time we finished talking i think he was ready to get his first headphone amp...just as i did last year with the magni)
Peace & "Music expresses that which cannot be said, and on which it is impossible to be silent." Victor Hugo
Three Toes of Fury (3ToF).
Ive said it before and i'll say it again...THANK YOU. Thank you for taking the time to write these chapters and share them with we head-fi-fans. Chapters like this one are a special treat as Im sure Im not alone in being a huge headphone/Amp/DAC fan who's always wanting to learn more about the....well, i'll call them the "ThreeToesofFury Four T's of Interest"....Technology, Terminology, Testing, and Totally-Tubular-Geeky-Info. (Had to shoehorn that fourth one in there...buuuut it seems to fit the bill...especially for fans of 80s new wave music..wink wink nudge nudge).
I am really impressed...and honestly a little vexed at times...by your willingness to share so much detail of what happens in the land o Schiit. As one who works within a technology based industry, i find that information hording is far more prevalent than information sharing...even within a company. The fact that you share so much, so freely, with such a positive attitude and approach, is a testimony to who you are and the company you run. Its one of the reasons I plan on remaining a life long Schiit customer. (Well, also because every Schiit product ive bought has blown me each time and
made such a difference in the music i listen too....Dats da fact jack!).
Keep up the great work and great writing dude. There's alot of us out here who love it. (And i think our ranks our growing...I.T. came by to fix my phone yesterday and asked about my Magni2U amp...by the time we finished talking i think he was ready to get his first headphone amp...just as i did last year with the magni)
Peace & "Music expresses that which cannot be said, and on which it is impossible to be silent." Victor Hugo
Three Toes of Fury (3ToF).
bigro
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Jason, what's the Measurements look like on the [REDACTED]?
Tuco1965
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A question for Jason, just wondering if we still might see spec pages for all the original gear. I know you mentioned that it was something you considered.
Tuco1965
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Yes on the website for older products though. Or am I missing where they are?
jcx
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a really well equipped audio electronic lab doesn't have to cost more than a US median new car if the instruments are bought used or cheap but good Chinese - just add up Jason's list
I'm very surprised to hear that anyone has actually found anything in a supposedly linear, not broke, audio electronic product with many frequency multitone test - I do expect it has have to have been messed up in software since merely competent analog doesn't have "smart enough" problems to only mess up on multitones and a major manufacturer's Audio DAC chip should have already been tested with them
complex multitones have been a Audio Precision menu item for decades - their FASTtest uses 30 log ratio frequencies for quick production testing, already described in 1992 - later cleaner article: http://www.hit.bme.hu/~papay/edu/Acrobat/Fund.pdf
the history includes Belcher1978 Noise Fill Test for speaker evaluation at the BBC - but they don't have a hearing impairment point plot left of -40 dB http://www.keith-snook.info/wireless-world-magazine/Wireless-World-1978/A%20new%20distortion%20measurement.pdf
the analog loopback plots of multitone spectra of "prosumer" PC soundcards I know of show nothing interesting despite Al Electrolytic coupling caps, indifferent op amps by audiophile standards
Dr Geddes GedLee metric might be an addition although he never went further into frequency variable distortion effects https://www.google.com/#q=gedlee+metric
his takeaway seems to be just check very low level linearity, with signal levels sweeping down into the noise with deep averaging - but biasing headphone amp outputs Class A is common which pretty much assures good low level/low order distortion in electronics
I'm very surprised to hear that anyone has actually found anything in a supposedly linear, not broke, audio electronic product with many frequency multitone test - I do expect it has have to have been messed up in software since merely competent analog doesn't have "smart enough" problems to only mess up on multitones and a major manufacturer's Audio DAC chip should have already been tested with them
complex multitones have been a Audio Precision menu item for decades - their FASTtest uses 30 log ratio frequencies for quick production testing, already described in 1992 - later cleaner article: http://www.hit.bme.hu/~papay/edu/Acrobat/Fund.pdf
the history includes Belcher1978 Noise Fill Test for speaker evaluation at the BBC - but they don't have a hearing impairment point plot left of -40 dB http://www.keith-snook.info/wireless-world-magazine/Wireless-World-1978/A%20new%20distortion%20measurement.pdf
the analog loopback plots of multitone spectra of "prosumer" PC soundcards I know of show nothing interesting despite Al Electrolytic coupling caps, indifferent op amps by audiophile standards
Dr Geddes GedLee metric might be an addition although he never went further into frequency variable distortion effects https://www.google.com/#q=gedlee+metric
his takeaway seems to be just check very low level linearity, with signal levels sweeping down into the noise with deep averaging - but biasing headphone amp outputs Class A is common which pretty much assures good low level/low order distortion in electronics
Tuco1965
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Where are there specs for Asgard, Magni, Modi, Lyr, Valhalla? These are the old products I'm talking about.
This was mentioned in the past and I believe Jason said he would consider putting them back.
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