Sweatometer actually...
I know your electronics would register hyperhidrosis+ on the sweatometer as they will have been designed by those lackadaisical engineers who care not for how it sounds they just want perfect measurements
You know, I sweated on that ... I started with sweatometer, looked at it, the word, for a bit, and then decided, hmmm, doesn't feel quite right - let's take that "o" out ... but, I can take being wrong, now and again ...
Hyperhidrosis?? Gee, I hate it when people throw really big words in - scares me a bit ... let's see ... hah! Not so bad, it's more the perfume hit that gets me ...
Hyperhidrosis?? Gee, I hate it when people throw really big words in - scares me a bit ... let's see ... hah! Not so bad, it's more the perfume hit that gets me ...
The thing is, Dick,
Everybody says it's a very nice headphone amplifier, and for that reason you've been cut a lot of slack, but you clearly don't understand digital technology.
Digital is a step change from analog.
You can no more understand digital on the basis of your analog experience than a car mechanic can understand an amplifier on the basis of his mechanical experience.
Try to imagine dealing with Enzo Ferrari if he started criticizing your headphone amp (OK, he's dead).
I'm sorry Mr. Ferrari, but you've got to go back to school...
The main reason a CFA has wider loop gains is not to do with lower feedback resistances in practical audio amplifiers. You do not have to pole split IF the loop gain is low. In VFA's the HF pole(s) locate lower down in frequency than the ULGF which necessitates compensation to deal with it. In a CFA you have lower loop gains and HF poles that locate above the ULGF so compensation can be easier and the loop gain bandwidth much wider. The sx-Amp loop gain bandwidth is 60 kHz for example.
CFA opamps rely often on adjusting the feedback resistor for compensation which adjusts the ULGF with internal comp cap. In high speed designs, this makes sense since bringing out comp pins would incur parasitics that would affect HF performance and especially settling times. For audio amllifiers no need to worry about that - use low feedback resistor values to preserve slew rate and a single cap from the TIS to the inverting input closes the loop at the desired frequency.
Note also that if you raise the OLG in a CFA, the LG behavior morphs to somewhat emulate that of VFA's and at some point you will have to deal with HF pokes that lie below the ULGF.
CFA opamps rely often on adjusting the feedback resistor for compensation which adjusts the ULGF with internal comp cap. In high speed designs, this makes sense since bringing out comp pins would incur parasitics that would affect HF performance and especially settling times. For audio amllifiers no need to worry about that - use low feedback resistor values to preserve slew rate and a single cap from the TIS to the inverting input closes the loop at the desired frequency.
Note also that if you raise the OLG in a CFA, the LG behavior morphs to somewhat emulate that of VFA's and at some point you will have to deal with HF pokes that lie below the ULGF.
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Untrue.
I can be as affirmative and non demonstrating than you, as you can see ;-)
Speaking from your "experience", right? Your only (poor) excuse, otherwise each half competent EE will shrug by reading the above.
And to add insult to injury, you always rejected each and every attempt to show you how feedback truly works. A true waste of time.
So I'm to understand approximately one dropped sample per minute imparts a "sound". This C2 error discussion comes up time and time again, I wish folks would at least think of the implications.
These days even without the flag you could record the digital out and compare to an an EAC rip.
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I remember a lecture from a guy who was a leading expert in optical communications, maybe 20 years ago. He kept on breaking off the lecture to say: 'Ask me how much bandwidth we can expect to offer you in the future', 'Ask me how much bandwidth we can expect to offer you in the future', and somebody had to ask him so he would get on with the lecture. Then he'd say, with an expression of total delight and surprise, as though he hadn't been expecting the question, 'Infinite! Infinite!'. This was OOK IIRC, just on the basis of frequency discrimination in the same pipe, but I guess there's a whole constellation of modulation techniques to come.
People coming from an analog background need to appreciate that we can design for an ARBITRARY bit error rate, and stop trying to second-guess the engineers who do so routinely, at least until they understand the techniques employed.
This whole argument about CDs is all water under the bridge, anybody clinging to a CDP is doing so for reasons of emotional attachment rather than any consideration of achievable fidelity.
People coming from an analog background need to appreciate that we can design for an ARBITRARY bit error rate, and stop trying to second-guess the engineers who do so routinely, at least until they understand the techniques employed.
This whole argument about CDs is all water under the bridge, anybody clinging to a CDP is doing so for reasons of emotional attachment rather than any consideration of achievable fidelity.
70 c2 I have seen ones with 100s and 100s of c2s . If 1 c2 per minute imparts a "sound " then day to day life must be an unfathomable experience of constant change and neuroplastic wondering synonym.
70 c2 I have seen ones with 100s and 100s of c2s . If 1 c2 per minute imparts a "sound " then day to day life must be an unfathomable experience of constant change and neuroplastic wondering synonym.
Interesting division of camps here seems there are lots or none.
The quote from Stereophile is interesting, I also found nothing using an original Phillips player but I only tried a few disks.
Their imaginations just can't take them that far.
It's like a bunch of Rain Men looking at the ground with their heads twitching and repeating over and over "Latest U2 has 70+ C2 errors. Latest U2 has 70+ C2 errors. Latest U2 has 70+ C2 errors..."
se
Thinking about it for a moment, it's the equivalent of arguing that an occasional pop or tick on an LP imparts a "sound" to the entire rest of the LP.
se
The original Philips heavy diecast swing arm single beam mechs and associated servos were unique in their tracking ability.
Dirty/scratched/gouged discs played without skipping forward/backward/repeating/stuttering.
The chipset also provided error flag output pins.
A DIY tracking test disk is to stick a wedge/triangle shaped piece of black insulating tape onto a cd in about the mid section of the disc.
This is most useful for adjusting tracking offset.
Interesting is that typical cd players with finely adjusted tracking offset will play through and correct data errors and produce clean audio output despite 2/3mm or so of no data.
This demonstrates the power of CIRC error correction.
Dan.
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Hi Stuart,
Still curious, but I am not disbelieving what Jan and yourself observed. There must be a reason for it. Not knowing makes me uncomfortable. Keep in mind that the C1 and C2 flags are normally not available to access on newer DSP chips. These flags can only be signaled by the DSP chip as the output data will always be valid. You can't detect C1 / C2 errors any other way except by comparing to the master file.
All,
One thing I hope has come out of this C2 flag talk is that with a good CD player, you will not notice small groups of these errors, let alone a single error. It just is not bit perfect, that's all. This has been my point all along. C2 errors exist, but you do not notice them under normal conditions. Cheap CD players suffer many more C2 errors and do not deal with them well. This is the prime reason why a cheap transport will not sound as good using the same DAC as a more expensive player. Using an in-box DAC is better than separates for other technical reasons.
Why do I enjoy playing CD's? Mostly because I don't have the patience to figure out which exact tracks I want to hear. Just grab a group and plop the thing into the player and I get music. Real easy, because I normally have a lot of other things on my mind. I even listen to records too! Why? I like the experience and some of the fuss I guess. 1/2 ounce of a sipper and just enjoy the music. This is satisfying, maybe because it's my fussing about that gets the music playing. Like enjoying a new preamp I designed, or even a "Kit Amp" like the SymAsym. Not as good as my modified Marantz 300DC, but still fun. Also like the various tube amplifiers I also use.
I think the C2 flag has been discussed to death so far. All questions can be answered by reading what has been posted already.
Hi SyncTronX,
The remote codes for a CT-17 were never made available for we poor technicians. I use another Carver remote to control my CT-6 bench preamp, and that's as close to what I get. If you can get a CT-17 remote, look at the resonator frequency, then the chip number and brand. That might allow you to maybe find a similar remote. There are probably ROM codes and / or pin strapping to determine a code set.
Hi OS,
Many thanks.
-Chris
Still curious, but I am not disbelieving what Jan and yourself observed. There must be a reason for it. Not knowing makes me uncomfortable. Keep in mind that the C1 and C2 flags are normally not available to access on newer DSP chips. These flags can only be signaled by the DSP chip as the output data will always be valid. You can't detect C1 / C2 errors any other way except by comparing to the master file.
All,
One thing I hope has come out of this C2 flag talk is that with a good CD player, you will not notice small groups of these errors, let alone a single error. It just is not bit perfect, that's all. This has been my point all along. C2 errors exist, but you do not notice them under normal conditions. Cheap CD players suffer many more C2 errors and do not deal with them well. This is the prime reason why a cheap transport will not sound as good using the same DAC as a more expensive player. Using an in-box DAC is better than separates for other technical reasons.
Why do I enjoy playing CD's? Mostly because I don't have the patience to figure out which exact tracks I want to hear. Just grab a group and plop the thing into the player and I get music. Real easy, because I normally have a lot of other things on my mind. I even listen to records too! Why? I like the experience and some of the fuss I guess. 1/2 ounce of a sipper and just enjoy the music. This is satisfying, maybe because it's my fussing about that gets the music playing. Like enjoying a new preamp I designed, or even a "Kit Amp" like the SymAsym. Not as good as my modified Marantz 300DC, but still fun. Also like the various tube amplifiers I also use.
I think the C2 flag has been discussed to death so far. All questions can be answered by reading what has been posted already.
Hi SyncTronX,
The remote codes for a CT-17 were never made available for we poor technicians. I use another Carver remote to control my CT-6 bench preamp, and that's as close to what I get. If you can get a CT-17 remote, look at the resonator frequency, then the chip number and brand. That might allow you to maybe find a similar remote. There are probably ROM codes and / or pin strapping to determine a code set.
Hi OS,
Many thanks.
-Chris
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Hi Dan,
The Pierre Verany test CD has a 2.4 mm defect. There are also defects that come in doubles. These defects also obliterate the track so that the offset of the tracking servo can either push a skip backwards or forwards. Your choice!
Your tape thing would be close to a Philps 5A test disc. But they used ink or paint of some kind for a sharp delineation between the defect and good area. This affects the servo amp recovery. Since the radial arm does not use E and F diodes, they inject an oscillation into the tracking amp to find the track edges so the servo can steer between them. About 600 Hz as I recall. This transport does have defects it can't handle though, and the (much) later VAM 1202 transport is a linear one. That one is pure junk.
-Chris
The Pierre Verany test CD has a 2.4 mm defect. There are also defects that come in doubles. These defects also obliterate the track so that the offset of the tracking servo can either push a skip backwards or forwards. Your choice!
Your tape thing would be close to a Philps 5A test disc. But they used ink or paint of some kind for a sharp delineation between the defect and good area. This affects the servo amp recovery. Since the radial arm does not use E and F diodes, they inject an oscillation into the tracking amp to find the track edges so the servo can steer between them. About 600 Hz as I recall. This transport does have defects it can't handle though, and the (much) later VAM 1202 transport is a linear one. That one is pure junk.
-Chris
http://en.wikipedia.org/Reed Solomon error correction
Disc damage causes unusually high tracking/focus servo actuator currents which due to typically lousy pcb earthing layouts modulate digital stage and audio stage supplies/earths.
Digital/dsp stage power supply modulation also causes integrated crystal oscillator stage modulation, and consequent timebase jitter artefacts.
If disc damage is sufficient to cause repeated C2 correctable errors, it is usual that DSP/DAC/audio output stage supplies will be sufficiently modulated to cause consequent audio output degradation.
Dan.
Disc damage causes unusually high tracking/focus servo actuator currents which due to typically lousy pcb earthing layouts modulate digital stage and audio stage supplies/earths.
Digital/dsp stage power supply modulation also causes integrated crystal oscillator stage modulation, and consequent timebase jitter artefacts.
If disc damage is sufficient to cause repeated C2 correctable errors, it is usual that DSP/DAC/audio output stage supplies will be sufficiently modulated to cause consequent audio output degradation.
Dan.
I've seen this claimed for 20 years or more. Zero actual supporting data.
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