I never questioned the existence of thin ethernet (aka 10Base2), I have installed and used 10Base2 networks. They were 10 megabits per second. That doesn't seem to be what Ed is talking about. It is just barely possible that Ed used a rare instance of the very early 2.94Mb/s pre-DIX Ethernet, but the last time I checked 2.94 is not the same as 1.
Also the Altos that Ed referred to had a hard drive with a removable 2.5MB cartridge. I doubt that was very useful for holding CD images. Even if he was using a busy 2.94Mb network and a file-transfer protocol with significant overhead, the transfer of 2.5 million bytes would take on the order of a minutes (more likely half that). I just don't buy that it was faster to unmount and carry the hard drive than to use the network. I'm also curious about the disk I/O throughput on those machines, I suspect the transfer would be bound by disk I/O not network speed.
Did-you mean, like in the Cain's grave ?Or my LP's, have fun with Arny be seeing you.
Don't know how you interpret what you read.
CDs weren't even around then.
First large file transfers could take hours. A bit of development has gone on since then. There were more than Altos around even then. Not even sure the Altos could talk to the others.
Where you around when a failure to load part of an email required starting all over?
Ever play Star Trek on an Alto? First really amazing multiplayer game.
This silly one up man ship on the past is rather boring. I played Space Wars on the PDP 1 as written at MIT in 1961 by Steve Russell and even had a printout of the source code until I threw it out in a house cleaning.
Sorry about the can of worms that started with "how to make a CD".
My understanding is that any significant group delay would make a square wave unrecognizable. What we have seen is a small explainable ripple. Did I miss someting?
I have a pc based speaker measurement system that can show phase /delay in the small microseconds using even on board sound cards in laptops. If digital is so far beyond redemption then the measurements are illusions?
Sent from my SGH-M919 using Tapatalk
My understanding is that any significant group delay would make a square wave unrecognizable. What we have seen is a small explainable ripple. Did I miss someting?
I have a pc based speaker measurement system that can show phase /delay in the small microseconds using even on board sound cards in laptops. If digital is so far beyond redemption then the measurements are illusions?
Sent from my SGH-M919 using Tapatalk
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No illusions
A-P note 29. Then do your home work and tests on G-D. What affect does it have on sound?
AP High Performance Audio Analyzer & Audio Test Instruments : Downloads
The highest amount of G-D will be closest to the sharp cut-off freq of the filter.
quick summary -- http://www-inst.eecs.berkeley.edu/~ee247/fa05/lectures/L2_f05.pdf
THx-RNMarsh
A-P note 29. Then do your home work and tests on G-D. What affect does it have on sound?
AP High Performance Audio Analyzer & Audio Test Instruments : Downloads
The highest amount of G-D will be closest to the sharp cut-off freq of the filter.
quick summary -- http://www-inst.eecs.berkeley.edu/~ee247/fa05/lectures/L2_f05.pdf
THx-RNMarsh
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Scott,
The Alto besides being the first graphics oriented computer and being networked also was very big on intuitive control action.
The game was quite simply mind blowing at that time. No text interface. You saw the view from the command chair and competed with others who could've be one of three types. Each type had some advantages and disadvantages. Scoreing was kept by noting the number of coke bottles in the floor by the navigation console.
No idea as to the limit on the number of players or the other limit planets to visit.
Nez
The issue was early digital limits and how the CD standard evolved from that
The technology of the early 70s set the standards for CDs. So 40 years latter is it a surprise things can be better. Yes D/As are much better, filtering is better but the sampling frequency limit that wasn't easy then is significantly improved today.
But we all know nothing beats a good wax cylinder!
DDemian.... I am not too interested in how to make a CD... wanted to see how much HF is produced and measured and made a filter to remove it. testing amp designs for increased distortion due to HF presence. The rest of this are fall-out issues unrelated to my curiosity about HF affects on analog amps down-stream. .
The 3 Biggies for CD audio sound is ---> the affect of HF on down stream analog audio amps; rolled off treble freq response; ripple when too fast input Tr or discontinuity occurs.
Beyond that is not much interest to me as 24/96 has made it all moot point.
I used the ML-9600 to see what the whole process does from adc input to dac output... re HF noise.
I really dont want to recap every time another person comes into the middle of the discussion. I made a filter which helps the PA and it does seem to improve the sound in several ways in my system.
I used a passive filter at 50KHz -3dB for the -9600. probabaly good for the 24/96 also. Have other CD and DVD tested for HF. OPPO this week. Then one with G-D correction players I found out about, also. The best one, I'll keep for my legacy CD collection. Only Mastered for HD 24/96+ downloads for future.
THx-RNMarsh
The 3 Biggies for CD audio sound is ---> the affect of HF on down stream analog audio amps; rolled off treble freq response; ripple when too fast input Tr or discontinuity occurs.
Beyond that is not much interest to me as 24/96 has made it all moot point.
I used the ML-9600 to see what the whole process does from adc input to dac output... re HF noise.
I really dont want to recap every time another person comes into the middle of the discussion. I made a filter which helps the PA and it does seem to improve the sound in several ways in my system.
I used a passive filter at 50KHz -3dB for the -9600. probabaly good for the 24/96 also. Have other CD and DVD tested for HF. OPPO this week. Then one with G-D correction players I found out about, also. The best one, I'll keep for my legacy CD collection. Only Mastered for HD 24/96+ downloads for future.
THx-RNMarsh
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My understanding is the group delay is the departure from linear phase shift or uniform delay. It reads like the application for a Bessel filter. Unfortunately the Bessel filter has a broader transition to the stop band.
50 KHz 9 pole filter is the recommended low pass/reconstruction filter for DSD. Has anyone measured an example? I have seen no recommendations for a different version for the DSD-256 or DSD-512. DSD without the filter is essentially delta sigma without a filter. Neither is a good idea.
50 KHz 9 pole filter is the recommended low pass/reconstruction filter for DSD. Has anyone measured an example? I have seen no recommendations for a different version for the DSD-256 or DSD-512. DSD without the filter is essentially delta sigma without a filter. Neither is a good idea.
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