- May 24, 2005
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http://recforums.prosoundweb.com/index.php/m/27065/0/?srch=pissed#msg_27065
Very long thread.......................
Just a snippet...
I am pissed because this thread is being taken over by salesmanship and ignorance of the basic design constraints of converters. Bob Ludwig knows better, he's got the tech chops. So I suspect you're taking him out of context.
If I gave you an endorsement, like Ludwig, Calbi and Sax, of how "great" the Apogee sounds with the Big Ben it is really a political spin of the converse. I really should be giving you a negative endorsement of how poorly it sounds WITHOUT THE BIG BEN.
By the way, I have nothing personally against you, Max, but my anger comes from that you approached this thread as a salesman and without concrete knowledge of how your own equipment works. Otherwise I would not be so confrontational. I hope you will learn something from this post; Apogee makes excellent converters, but there is great room for improvement once you learn the science and the facts and forget the hype....
Saying that a converter sounds better with a "great" external clock is attempting to justify poor engineering. You are rationalizing the purchase of a Big Ben when the whole purpose of a converter should be to AVOID the NEED for a Big Ben! It is a big Left-handed compliment to say that a converter sounds better with an external clock!
Let's remember how a PLL works and how an internal crystal works, as described clearly by Dan Lavry earlier in this thread.
I really don't care how much the Apogee is improved by the Big Ben. I can buy numerous well-designed converters which perform as well or better without it, and reject the jitter well-enough from external clocks so as not to need the Big Ben.
The very fact that it is IMPROVED is a demonstration that not enough attention was made to the internal design of the converter itself. That includes both the PLL and the internal crystal. Both of which should perform excellently without any external BANDAIDS, because that's what the Big Ben is, a BANDAID. The CURE, not the BANDAID, should have been within the converter's internal design not external to it. That includes the PLL and the crystal. The ABSOLUTE best performance of a well-designed converter MUST be that the internal crystal performance is indistinguishable from the external PLL performance. If the PLL performs one iota better than the crystal, then the designers have not done their homework.
For the record, I have auditioned two other Apogee converters post the AD-8000 and been underwhelmed by their sonics. I found the Rosetta and the PSX-100 to be colored and veiled, under blind tests, compared with a straight wire, analog sources, and against other models of converters. I am prepared to be impressed by the later designs; everyone makes a mistake sometime. But don't mess with me with this Big Ben Nonsense. The science and the basic principles of engineering design are against you. This is not-brand-specific. There is no mysterious "voodoo" about the Big Ben and what it is or is not doing for the Apogee or any other converter.
It costs about $35 in parts, coupled with good grounding, layout and power supply design, to build a crystal oscillator in your converter that will outperform any external Big Ben or whatever. So quit the hype, please.
Was it an economic decision to cripple the Apogee? I can understand if you want the consumers to save $600 (or whatever the Big Ben costs), buy the converter, get fair performance without it at a decent price (I assume). If you are willing to admit that it was an economic decision to design the converter in this way, then I have no quarrel with you. Every designer has to face economic compromises, and maybe the Apogee's clock circuit was one of those compromises.
Just don't tout the Big Ben as a big achievement when it is really the equivalent of a better PCV valve on a poorly-designed internal combustion engine!
Do you have FFT measurements of your converter's jitter performance on internal and external clock comparable to that of, for example:
DCS, Lavry, Benchmark, or TC system 6000.
All of the above converters do not require a Big Ben to demonstrate textbook-perfect jitter performance.
Let's see your measurements, stick to the facts and skip the hype. In a converter that sounds poorly or worse with poor external clocks, or poorly with internal clock, it will demonstrate poor jitter rejection and poor internal crystal performance. So you only get an A+ with Superman on the external wordclock. You'll have to justify that decision with economics. If the cost of the Apogee WITH Big Ben justifies its sonics, then ok... but it's not a good sign.
Very long thread.......................
Just a snippet...
I am pissed because this thread is being taken over by salesmanship and ignorance of the basic design constraints of converters. Bob Ludwig knows better, he's got the tech chops. So I suspect you're taking him out of context.
If I gave you an endorsement, like Ludwig, Calbi and Sax, of how "great" the Apogee sounds with the Big Ben it is really a political spin of the converse. I really should be giving you a negative endorsement of how poorly it sounds WITHOUT THE BIG BEN.
By the way, I have nothing personally against you, Max, but my anger comes from that you approached this thread as a salesman and without concrete knowledge of how your own equipment works. Otherwise I would not be so confrontational. I hope you will learn something from this post; Apogee makes excellent converters, but there is great room for improvement once you learn the science and the facts and forget the hype....
Saying that a converter sounds better with a "great" external clock is attempting to justify poor engineering. You are rationalizing the purchase of a Big Ben when the whole purpose of a converter should be to AVOID the NEED for a Big Ben! It is a big Left-handed compliment to say that a converter sounds better with an external clock!
Let's remember how a PLL works and how an internal crystal works, as described clearly by Dan Lavry earlier in this thread.
I really don't care how much the Apogee is improved by the Big Ben. I can buy numerous well-designed converters which perform as well or better without it, and reject the jitter well-enough from external clocks so as not to need the Big Ben.
The very fact that it is IMPROVED is a demonstration that not enough attention was made to the internal design of the converter itself. That includes both the PLL and the internal crystal. Both of which should perform excellently without any external BANDAIDS, because that's what the Big Ben is, a BANDAID. The CURE, not the BANDAID, should have been within the converter's internal design not external to it. That includes the PLL and the crystal. The ABSOLUTE best performance of a well-designed converter MUST be that the internal crystal performance is indistinguishable from the external PLL performance. If the PLL performs one iota better than the crystal, then the designers have not done their homework.
For the record, I have auditioned two other Apogee converters post the AD-8000 and been underwhelmed by their sonics. I found the Rosetta and the PSX-100 to be colored and veiled, under blind tests, compared with a straight wire, analog sources, and against other models of converters. I am prepared to be impressed by the later designs; everyone makes a mistake sometime. But don't mess with me with this Big Ben Nonsense. The science and the basic principles of engineering design are against you. This is not-brand-specific. There is no mysterious "voodoo" about the Big Ben and what it is or is not doing for the Apogee or any other converter.
It costs about $35 in parts, coupled with good grounding, layout and power supply design, to build a crystal oscillator in your converter that will outperform any external Big Ben or whatever. So quit the hype, please.
Was it an economic decision to cripple the Apogee? I can understand if you want the consumers to save $600 (or whatever the Big Ben costs), buy the converter, get fair performance without it at a decent price (I assume). If you are willing to admit that it was an economic decision to design the converter in this way, then I have no quarrel with you. Every designer has to face economic compromises, and maybe the Apogee's clock circuit was one of those compromises.
Just don't tout the Big Ben as a big achievement when it is really the equivalent of a better PCV valve on a poorly-designed internal combustion engine!
Do you have FFT measurements of your converter's jitter performance on internal and external clock comparable to that of, for example:
DCS, Lavry, Benchmark, or TC system 6000.
All of the above converters do not require a Big Ben to demonstrate textbook-perfect jitter performance.
Let's see your measurements, stick to the facts and skip the hype. In a converter that sounds poorly or worse with poor external clocks, or poorly with internal clock, it will demonstrate poor jitter rejection and poor internal crystal performance. So you only get an A+ with Superman on the external wordclock. You'll have to justify that decision with economics. If the cost of the Apogee WITH Big Ben justifies its sonics, then ok... but it's not a good sign.
