Zaikesman...Correct. This is a multichannel system, and digital outputs are not available. |
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Albertporter...That depends on the definition of "better". |
Albertporter...I am very sad to hear about Dave's death. We did have a most enjoyable conversation by E-Mail, and exchanged some CD's that we thought represented exceptional performances.
About vinyl...PLEASE don't consider any comment I might make as an "attack". There are few enough of us audiophiles that we don't need a circular firing squad. Debate, yes, but an argument, no.
Now I will go play the Joshua Bell/ Ashkenazy performance of the Tchaikovsky violin concerto which Dave sent to me, and raise a glass to his memory. |
Johnnantais...You are quite correct that there is great potential for improvement of vinyl-based audio. I know that, because I had DBX records and playback electronics, and I found that all the well known problems of vinyl were drastically reduced by this system. Audiophiles missed the boat on this one, although stupid marketing by DBX played a role. If I had to describe DBX records in a nutshell, I would say that it amounts to dynamic equalization to replace the RIAA curve. |
Albertporter...Texas is the land of big everything...even, I notice, opinions! I thought we agreed that some aspects of digital, like convenience, to pick a non-controversial aspect, are "better" than vinyl. I really don't see why people who can't agree with your view need to be personally vilified. |
Gregm...I agree that a live feed sometimes has a certain quality which I have not heard from any recorded media. However, FM radio has some limitations. As you may know, FM radio consists of two signals, a mono one up to 19KHz and a multiplexed one, (Left minus Right) above 20 KHz. The two signals (mono and demultiplexed L-R) are mixed to get Left and Right.
Have you ever listened to the L-R signal by itself? Even with a strong RF signal the L-R signal is pretty bad, and this gets mixed with the mono signal to get stereo. It's a wonder that it sounds as good as it does. Of course as the RF signal gets weaker the L-R signal goes from bad to awful, and we switch our receivers to mono.
I know that you said "improved" FM. Fat chance. What you will get is digital, and here we go again with the debate!
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Albertporter...Dolly Parton has very small feet. She explains this by "things don't grow well in the shade".
Psychicanimal...Do it and let us know what happens. I might do mine. |
Shadorne...How many bits you need depends on the size of the bits. Lets suppose that the analog signal dynamic range going in to the A/D is 0 to 1.5 volts. If I make each bit 0.5 volts I can cover the range (represent a 1.5 volt sine wave) with just three bits. (Sign and two bit magnitude).
0 1 1 ..... -1.5 volts
0 1 0 ..... -1.0 volts
0 0 1 ..... -0.5 volts
1 0 0 ..... +0.0 volts
1 0 1 ..... +0.5 volts
1 1 0 ..... +1.0 volts
1 1 1 ..... +1.5 volts
Obviously the resolution is terible! If I make each bit 0.05 volts the resolution will be better, but I will need a lot more bits.
Until you decide upon a particular bit scaling, and analog signal gain the dynamic range and number of bits are not related. |
Rauliruegas...I don't know why you CAN'T have more than 24 bits in a word...the missile guidance computer I used to work with used 32 bit words and much of the data and calculations were "double precision" 64 bit words. But as you say, HOW you use the bits is most important. Our music is "fixed point" data. When you play a quiet section of music through 24 bit digital converters you are actually only using perhaps 8 to 10 of the lowest bits. Not that great resolution. I have recently discovered the importance of keeping the analog signal up before the A/D of my Behringer DEQ2496 equalizer, although this requires me to attenuate the output going to my power amps. A better way to use the available bits, whether 16 or 24, would be "floating point". (A few bits are used to indicate the scaling of the remaining bits of data). This format provides the best resolution for signals of all amplitudes. In the DEQ2496 after the A/D input , a 32 bit floating point digital signal processing (DSP) module performs the equalization and other functions, so we know it can be done. Now we need a disc (or other digital media) that employs floating point. |
Zaikesman...There is no rule to the effect that the least significant bit (LSB) be equal to the analog noise level. Usually the LSB is smaller, so that several of the lowest bits toggle on and off due to noise. One might define the noise floor as the voltage corresponding to the bit which never changes unless there is a deliberate signal. The range from zero up to the maximum signal level can be divided up into as many steps as you like (within technology constraints). |
Three audiophiles agree on something!!! The planets must be aligned. |
Zaikesman...."subjective audition testing done in this area?" That is exactly what I did with my Behringer DEQ2496. I noticed that the input signal level, displayed by a string of LEDs, never got even half way up, meaning that only the lower bits of the A/D were being used. Upon consideration this is not surprising since the DEQ2496 is professional gear, and expects line level signals to be higher than typical consumer electronics. I have introduced attenuation between the output of the DEC2496 and my power amps, and cranked up the preamp gain so that the peak level for a complete CD (detected and loged by the DEC2496) is 6 dB or less below cliping. Now I am utilizing all the bits I paid for. In my subjective opinion, it sounds better. |
Shadorne....The number of D/A states is fixed for a device of a given number of bits. The voltage step from one state to the next (quantization) depends on how the D/A is designed. That said, the numbers you quote are about right for D/As used in audio applications. And with 0.03 mv for a CD and 0.2 microvolt for a DVDA one would think that either would follow a line level analog waveform darned well. However, don't forget that gain follows the D/A, and by driving the input harder the gain following can be less, so that one bit AT THE SPEAKER is a smaller voltage.
I notice much greater improvement by this adjustment of gains than with ceramic outlet covers :-) |
