Hi,
I always judge a DAC's Bandwidth and dynamic range with an AP2, not sure how you would use cymbals or trumpets to measure frequency response or dynamic range.
I use recordings of cymbals and other items for listening evaluation of "realism". I have not yet found any "measurement" or sets of measurements that helps me to judge this without listening.
Ciao T
I always judge a DAC's Bandwidth and dynamic range with an AP2, not sure how you would use cymbals or trumpets to measure frequency response or dynamic range.
I use recordings of cymbals and other items for listening evaluation of "realism". I have not yet found any "measurement" or sets of measurements that helps me to judge this without listening.
Ciao T
What! You don't think that could happen?
Well... If speed of light is not constant, may be...
Well... If speed of light is not constant, may be...
Assuming the filters are applied you have to be right and I'm wrong. But then, I'm wrong about lots of things. Here's another:
"Public Opinion Polls and Perceptions of US Human Spaceflight" (Roger Launius) - Academia.edu
I've moved the car posts over to a new thread, "Car Talk," in the Lounge. If I lost any on the way, my apologies.Most interesting paper, I'd not seen that.
"Professor F. Brock Fuller jangling his own ring of keys."
I love it.
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A profound statement! I agree!
Kidding aside, what am I worried about? I've belonged to the widebandwidth school from my beginnings. You know, the freaks who think that if the electronics don't hit at least 200 kHz at full power, under any conditions, they're no good.
As for the speakers, Audax' data sheet showed a peak at around 25 kHz, like 20 kHz -1 dB, 22 kHz 0 dB, 25 kHz +1 dB, and decaying quickly after that. That's all I can do, except perhaps rig up some elcronic compensation, but I honestly feel that would do more harm than help.
Originally Posted by Wavebourn
After analog + digital filtering?
http://www.diyaudio.com/forums/ever...ads-why-they-make-no-sense-4.html#post2940181
Scandal Brewing in High Resolution Downloads? | Computer Audiophile
It does seem filters aren't always applied properly, so yes, some recordings might have traps for unwary listeners.
After analog + digital filtering?
What! You don't think that could happen?
http://www.diyaudio.com/forums/ever...ads-why-they-make-no-sense-4.html#post2940181
Scandal Brewing in High Resolution Downloads? | Computer Audiophile
It does seem filters aren't always applied properly, so yes, some recordings might have traps for unwary listeners.
JB and my old aquaintance Jerry Sussman of MIT are both very interested in this >100kHz stuff. Jerry is a brilliant guy and consumate scientist so I can not dismiss this lightly.
When Sussman teamed up with Boyk I think it enriched JB's perspective immensely. That paper they did on feedback (of even the simplest local sort) affecting the IM distortion products, even though the models of tubes, bipolars, and FETs were idealized, actually got Jim to say something almost positive about bipolar transistors!
(People may recall JB's T-shirt, emblazoned with "Digital finishes what the transistor began")I passed that paper to a friend who was strongly influenced as a Caltech undergrad when taking JB's class. Oddly, he said something to the effect "Well, it's about IM distortion". He wasn't that interested, which astonished me, and I entertained suspicions that Boyk had fallen from grace by countenancing something besides hollow-state devices.
It reminded me a bit of another friend from high school days, very bright guy, who had two heroes: Bertrand Russell and B. F. Skinner. When there was some Russell-Skinner contretemps, he decided Skinner was the "harder-headed" one and sided with him, something I thought was a terrible mistake. But this was high school. Someone said they'd run into him a bit later walking the streets of Chicago, barefoot and holding a flower.
Brad
Yes, that is how I am leaving it, unless extended listening says I did something wrong. I did not put the degeneration in the input CM and really did not see a need to speed anything up by bypassing the spreader.
There is no limit where one could go with FET inputs, doubling the outputs, newer transistors, metal film resistors, splitting the power rails with a cap multiplier or pi filter, DC servo, whatever. It's a 35 year old amp with no protection, power control, mute, or modern niceties. The physical config is a royal pain to work on. Best to leave it be and get a newer amp to play with. I learned a lot and that was the goal.
Of course, I still have no clue what parameters make my wife prefer the Rotel to the Hafler or Parasound. I believe it is something aggravating the tweeter deficiencies, so I want to get back to better tweeters. Better speakers may change our views of the amps completely. The B&K ST-140 failed her tests, and it is still recognized as one of the easiest amps to listen to out there. (for only money) I have a lot to digest.
There is no limit where one could go with FET inputs, doubling the outputs, newer transistors, metal film resistors, splitting the power rails with a cap multiplier or pi filter, DC servo, whatever. It's a 35 year old amp with no protection, power control, mute, or modern niceties. The physical config is a royal pain to work on. Best to leave it be and get a newer amp to play with. I learned a lot and that was the goal.
Of course, I still have no clue what parameters make my wife prefer the Rotel to the Hafler or Parasound. I believe it is something aggravating the tweeter deficiencies, so I want to get back to better tweeters. Better speakers may change our views of the amps completely. The B&K ST-140 failed her tests, and it is still recognized as one of the easiest amps to listen to out there. (for only money) I have a lot to digest.
Chomsky was greatly raised in my esteem by taking on Skinner. BTW my wife and I went to an open house next door to the Skinner residence many years ago, there goes the neighborhood.
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