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mchale
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Analog compression...

I find the complaints about lossy forms of digital compression from the vinyl crowd quite ironic considering the crude form of analog compression represented by RIAA EQ. This analog compression scheme has been ruthlessly imposed on every piece of vinyl produced in the last fifty years... COME ON!

bobedaone
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Re: Analog compression...

I believe you're referring to two different meanings of the word "compression".

http://www.stereophile.com/news/061107compression/

mchale
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Re: Analog compression...

No... Studio compression is compression of the amplitude of the waveform envelope. What I am referring to is the reduction of frequency components in order to keep the needle on the record. Please check the following reference.

http://en.wikipedia.org/wiki/RIAA_equalization

The inverse of the curve shown in the figure "The RIAA equalization curve for playback of vinyl records." is the information that had to be removed in order to get the vinyl created.

bobedaone
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Re: Analog compression...

I appreciate your taking the time to clarify your point. I was thrown off when you mentioned "lossy compression" in the original post, which is not equatable to the dynamic compression encountered in digital and analog playback. That's a very informative Wiki link.

tandy
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Re: Analog compression...


Quote:
No... Studio compression is compression of the amplitude of the waveform envelope. What I am referring to is the reduction of frequency components in order to keep the needle on the record. Please check the following reference.

http://en.wikipedia.org/wiki/RIAA_equalization

The inverse of the curve shown in the figure "The RIAA equalization curve for playback of vinyl records." is the information that had to be removed in order to get the vinyl created.

Information removed? Would you please elablorate.

Thanks.

mchale
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Re: Analog compression...

Starting off with a flat response an analog filter is used to remove 20db in the range of 20hz-1k and in the range from 1k-20k it is boosted by 20db. So what we end up with is a seriously stepped on signal that is transfered to the vinyl. To recover the curve the signal is blindly boosted at the low end and attenuated at the high end. Remembering that these filters are analog, primary frequencies and intermodulation products are inevitably lost... Hence information removal.

tandy
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Re: Analog compression...

"Starting off with a flat response an analog filter is used to remove 20db in the range of 20hz-1k and in the range from 1k-20k it is boosted by 20db. So what we end up with is a seriously stepped on signal that is transfered to the vinyl."

>Attentuation and phase shift. That is why there is a standard, so the deemphasis circuit results in a flat response and no phase shift.

>What about a volume control. Does it "remove" some signal? Afterall, it reduces the signal.

"To recover the curve the signal is blindly boosted at the low end and attenuated at the high end."

>That is why the standard. The result of pre and de is flat response. There is no "blindly" about it. Both pre and de works at specific time constants.

>One could also wonder about OP amps in the analog section. OP amps are limited bandwidth, high gain devices that use feedback to shape their response as well. In this case, widening the frequency response.

"Remembering that these filters are analog, primary frequencies and intermodulation products are inevitably lost... Hence information removal."

>Got proof? Well, what about DACs? Is the digital to analog section have a common power supply? If so, then digital and analog signals are interfering with each other through the regulator. It isn't perfect.

>Maybe more than that, with both digital and analog in one chip, the magnetic fields due to current flow of both digital and analog interferes, feeds to each other by proximity. The higher the audio frequency the more the problem.

>To these ears, LPs beat digital from every player I have heard. Haven't tried from a computer yet.

mchale
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Re: Analog compression...


Quote:
"Starting off with a flat response an analog filter is used to remove 20db in the range of 20hz-1k and in the range from 1k-20k it is boosted by 20db. So what we end up with is a seriously stepped on signal that is transfered to the vinyl."

>Attentuation and phase shift. That is why there is a standard, so the deemphasis circuit results in a flat response and no phase shift.

>What about a volume control. Does it "remove" some signal? Afterall, it reduces the signal.

"To recover the curve the signal is blindly boosted at the low end and attenuated at the high end."

>That is why the standard. The result of pre and de is flat response. There is no "blindly" about it. Both pre and de works at specific time constants.

If the filter that shaped the signal before it went onto vinyl is the exact compliment of the one used to recover the signal, you are correct. Unfortunately as has been pointed out elsewhere even the type of solder used can make audible differences in the sound. The chances that the filter in your pre-amp compliments the one in the studio are, by this logic, nil. This happens even though both filters nominally meet the RIAA standard. Unfortunately they are both built from analog components - remember the solder!

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Re: Analog compression...


Quote:

Quote:
"Starting off with a flat response an analog filter is used to remove 20db in the range of 20hz-1k and in the range from 1k-20k it is boosted by 20db. So what we end up with is a seriously stepped on signal that is transfered to the vinyl."

>Attentuation and phase shift. That is why there is a standard, so the deemphasis circuit results in a flat response and no phase shift.

>What about a volume control. Does it "remove" some signal? Afterall, it reduces the signal.

"To recover the curve the signal is blindly boosted at the low end and attenuated at the high end."

>That is why the standard. The result of pre and de is flat response. There is no "blindly" about it. Both pre and de works at specific time constants.

If the filter that shaped the signal before it went onto vinyl is the exact compliment of the one used to recover the signal, you are correct. Unfortunately as has been pointed out elsewhere even the type of solder used can make audible differences in the sound. The chances that the filter in your pre-amp compliments the one in the studio are, by this logic, nil. This happens even though both filters nominally meet the RIAA standard. Unfortunately they are both built from analog components - remember the solder!

Same thing with any component, including DACs, phono stages, line preamps, amps, and speakers.

Some RIAA manufacturer's claim to be within 0.1db accurate. Hopefully, they are correct, or even closer.

As far as matching and solder, I think the thing to remember is to pick the phono stage, or line preamp as neutral as possible. As you point out, correctly, this is extremely difficult. But then it is also difficult with any component, whether tube or solid state, whether analog or digital is the format.

I guess this is what audio is all about, trying to get as close as possible to the holy grail.

mchale
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Re: Analog compression...


I guess this is what audio is all about, trying to get as close as possible to the holy grail.

Sure is.. I think we're on the same page

CECE
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Re: Analog compression...

LP beats digital everytime? Nope. Ever hear of DSD/SACD? Snap crackle pop, now that's realistic sound reproduction. vinyl has been made obsolete you know. How does a format with limited freq response, limited dynamic range, extremely high noise levels, physically imposing inconvient to use beat digital everytime. DSD/SACD wins all the time. Your ears need cleaning. Or surgery..cus' vinyl does not beat digital everytime. DSD sure do beat anyting all the time. Snap crackle pop, aaaahhh, those where the days. His master's voice, give me a nice mechanical groove to grind some sound from

tandy
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Re: Analog compression...

"LP beats digital everytime? Nope. Ever hear of DSD/SACD? Snap crackle pop, now that's realistic sound reproduction. vinyl has been made obsolete you know."

>Hmmmm. Who said everytime. I said the best LPs and best digital, I like the LPs better. Seems to me LPs sound a little more natural.

"How does a format with limited freq response,"

>Interesting, how high do CDs, dsd, sacd go in frequency response dup??? Need some numbers dup.

"limited dynamic range,"

>Didn't someone post a link that demonstrated that the Relative dynamic ratio was better with LPs than with digital? Maybe I am wrong though.

"extremely high noise levels,"

>I don't have that much problem. Besides, at a concert, I hear noises all the time.

>CDs are easier to use, granted that.

CECE
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Re: Analog compression...

DSD SACD go out ot around DC-100KHz. 120dB dynamic range, www.sa-cd.net see what they gots. LP is like the soon to be stopped being used in Europe, the incandescant lamp, banned to be in Australia...Vinyl is past it's prime, Large lamp companies, Philips, GE, Osram are working on eliminating the inefficent lamps in Europe, vinyl is the audio equivilent. Everyone seems to think incandescant is better color rendering, but it is actually a better room heater. CFL/LED modern reasons to not use obsolete lamps. DSD/sACD maodern reasons LP is obsolte. If ya gotta spend $100K on a TT to sound like a $300SACD player....it's gotta be Chinese....Sum Ting Wong. And i would say DSD sACD will still be better, snap crackle pop..oopps forgot to vacuum my records.....Do you think analog tv is better than digital HDTV? If you do you is nutz. Just like DSD versus Vinyl....Jumping up every 20 minutes to flip a record is also just a pain in the A++.

tandy
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Re: Analog compression...


Quote:
DSD SACD go out ot around DC-100KHz. 120dB dynamic range, www.sa-cd.net see what they gots. LP is like the soon to be stopped being used in Europe, the incandescant lamp, banned to be in Australia...Vinyl is past it's prime, Large lamp companies, Philips, GE, Osram are working on eliminating the inefficent lamps in Europe, vinyl is the audio equivilent. Everyone seems to think incandescant is better color rendering, but it is actually a better room heater. CFL/LED modern reasons to not use obsolete lamps. DSD/sACD maodern reasons LP is obsolte. If ya gotta spend $100K on a TT to sound like a $300SACD player....it's gotta be Chinese....Sum Ting Wong. And i would say DSD sACD will still be better, snap crackle pop..oopps forgot to vacuum my records.....Do you think analog tv is better than digital HDTV? If you do you is nutz. Just like DSD versus Vinyl....Jumping up every 20 minutes to flip a record is also just a pain in the A++.

>If the music sounds better, who cares about flipping an LP over every 20 minutes? Certainly not one looking for the best sonics.

>But even an SACD and DVD player has analog OP amps, with gobs of feedback, in the audio path. Plus cheap resistors, caps etc.

>And the cheap solid state mute circuits I have seen leave much to be desired. By pass it and the sound immediately improves. At least in my cd player.

CECE
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Re: Analog compression...

Cheap mute ckts? What kind of stuff do you listen to? Properly designed mute ckts have no effect on teh sound. Cheap caps and resistors, proper designed units have the components it needs to do teh job. Pricey parts doesn't mean it sounds any better. Just means you pay more than you should for no gain in performance. Using your logic, what price is then a good SACD palyer? If an SACD player has "cheap" analog outputs, what is coming off a TT, cheap analog output. I'm sure YOUR pre amp is the most accurate, perfect best components in the pre amp possible, working on that ANALOG signal. If you have to spend $100K on a platter with a motor to equal what a SACD player does for much much much less, it proves DSD/SACD is better. No vinyl has the freq response, the dynamic range, the incredible low noise, that DSD/SACD has. LP playback is listening to some high distortion, highly masked reproduction. How much do you have to spend on a cartridge to equal DSD/SACD? Accept it, vinyl is a dead format, nowhere near what DSD/SACD can do. And I have lotsa LP's it's still aan obsolete, dead format, with less to offer for superb reproduction. LP is like an incandescant lamp. Obsolete. Hey, matter o' fact didn't Edison work on both....yeah nothing like 1880 technology for 21st century sound reproduction. Mary had a little lamb......who wound up on a stick for shiskabab

tandy
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Re: Analog compression...

Interesting how dup twists, puts words into others mouths, and simply makes misleading statements.

"Cheap mute ckts? What kind of stuff do you listen to? Properly designed mute ckts have no effect on teh sound."

>Based on what dup? You have already basically admitted you haven't experimented. We know you haven't tried removing the ss mute circuit in your player. Even basic electronic knowledge would demonstrate problems with ss mute circuits. So you are providing info without any knowledge of the subject. So dup misleads again without any knowledge of electronics.

"Cheap caps and resistors, proper designed units have the components it needs to do teh job. Pricey parts doesn't mean it sounds any better."

>First, who said the parts are pricey? Second, since you haven't tried the parts, you have no idea.

All of us have repeatedly demonstrated your lack of knowledge and understanding, so are you stating things when you have no experience on the subject?

"Just means you pay more than you should for no gain in performance."

>Again, how would you know if you haven't done the research? So you are simply throwing out statements without varifying whether they are true or not.

"Using your logic, what price is then a good SACD palyer? If an SACD player has "cheap" analog outputs, what is coming off a TT, cheap analog output."

>Nope, the difference is the phono stage is separate, so one can upgrade. But with any player, one is pretty much stuck with what is included. And from what I have seen, carbon resistors just don't make it. (Remember, you stated newer is always better, so why the outdated carbon resistors from 40 years ago? Don't be a hypocrit dup.)

"If you have to spend $100K on a platter with a motor to equal what a SACD player does for much much much less, it proves DSD/SACD is better."

>There are plenty of great tt out there that are inexpensive. Don't be a nutcase by condemning the whole industry over a high priced tt.

"No vinyl has the freq response, the dynamic range, the incredible low noise, that DSD/SACD has."

>Unfortunately, you didn't mention tonality, naturalness. I have yet to hear an SACD that sounded as good as a good LP.

"LP playback is listening to some high distortion, highly masked reproduction."

>You must have some pretty poor equipment dup. The LP sounds more natural more open to me, and I have heard several systems at stores.

"How much do you have to spend on a cartridge to equal DSD/SACD? Accept it, vinyl is a dead format, nowhere near what DSD/SACD can do."

A $40 cartridge sounded just as good as the players I have heard.

"And I have lotsa LP's it's still aan obsolete, dead format, with less to offer for superb reproduction."

>Maybe you should try getting some good equipment?? By the way, LP sales are increasing, so why the misleading comment that LP is dead??

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