I found the OPPO marginal, and I had to modify it to make it sort of OK. I still don't play much digital, even though I have made a lot of progress in making it listenable to me.
When it comes to digital, I must admit that I have avoided it mostly for decades. Oh sure, I have the digital textbooks, but I just can't get into them seriously.
I first thought that just improving the I-V with a discrete fet stage would do wonders, coupled with better analog (at least) power supplies, but discussions with people who know more than I do have convinced me that I just don't have enough to offer at this time to go through the time and trouble to make a D-A converter playback at this time. It is better to depend on others for this. I don't want my name associated with another 'me too' D-A.
When it comes to digital, I must admit that I have avoided it mostly for decades. Oh sure, I have the digital textbooks, but I just can't get into them seriously.
I first thought that just improving the I-V with a discrete fet stage would do wonders, coupled with better analog (at least) power supplies, but discussions with people who know more than I do have convinced me that I just don't have enough to offer at this time to go through the time and trouble to make a D-A converter playback at this time. It is better to depend on others for this. I don't want my name associated with another 'me too' D-A.
What about their method is superior? Their choice of a non-audio DAC with glitch, and then failing to get good results out of it?
It is not superior, it is urban legend done poorly.
To add on to what Richard is proposing, John, look into using Roon as a file management system. They have just integrated Qobuz streaming which allow up to 192kHz/24 bit. I have been beta testing the integration and,sonically it is amazing.
The Roon Radio is a great way to discover music as it chooses between your own files and what Qobuz offers. Nothing less then 16/44.
After two day trials, I am hooked. High quality files will help you determine what circuit sounds better.
The Roon Radio is a great way to discover music as it chooses between your own files and what Qobuz offers. Nothing less then 16/44.
After two day trials, I am hooked. High quality files will help you determine what circuit sounds better.
You are being overly modest John.
As observed by Richard, Tournesol and others as well, "the analog portion was the most variable and audible". Your fans will be there when you are ready.
Depends what you mean by 'evaluate.' It isn't a new idea, actually. He is trying to reduce HF clock noise from some low cost current output dac chips so it doesn't cause too much distortion in I/V opamps. It likely works about like he says. Not something applicable to ESS Sabre dacs though, since it would increase distortion with them.
With a very different cursus in our lives (country, culture, professional experience etc...) may-be, it is because we have similar ways to approach the audio reproduction ?
Trying a keep a good balance between knowledge (with a lot of pinces of salt), sensibility of our senses (with a lot of mistrust), open mind, curiosity and care to be as less as possible under any kind of influence ?
It is reassuring to think that if others come to the same conclusions as ours, they might not be so wrong ?
I used to say to all the young people I trained: "Never believe, even about "science", check everything out of your own experience."
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John, how to say that with all the tenderness for your work that your passion and your talent can generate ?You are being overly modest John.
As observed by Richard, Tournesol and others as well, "the analog portion was the most variable and audible". Your fans will be there when you are ready.
Sometimes, it is by making love with a girl that we start to love her.
Digital is everywhere around. Do not you put yourself in a sarcophagus like a mummy.
Take the best DA converter you can find. (not the most expensive ;-) and make him love by all ends. I'm sure you will fall in love, we will benefit from your children, and it will be much more useful than to return in loop on vinyls, old courtesan at the end of career that nothing can surprise any more. What an interest to perfect diligences, nowadays ?
You had put your name on near everything analog in electronic for audio. preamplifiers, amplifiers, tape recorders. There is a wall where you have not yet put your tag: The digital. "The John Curl DA converter."
I'm sure it might interest some marketing prince and, for you, good time working on it.
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Understatement, they told me I was wrong. Dick was there, it was a LONG time ago. IIRC it was Small of Thiele-Small that said a 5534 with the 2000pF cap was all you need, nothing else would make a difference.
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It's an implementation of a passive filtering scheme.
This HF noise has been written is what makes opamp ICs unsuitable for the task (while discrete implementations survive )
George
Parasound P5 page and Stereophile review:
Model Halo P5 << Parasound
Parasound Halo P 5 2.1-channel D/A preamplifier | Stereophile.com
Now regarding Halo A21 power amplifier, my comments:
+ points:
- high power, it meets power specs, 400W/4ohm
- it meets most of the specs as shown at Parasound web and datasheet
- very good dynamic range
- points:
- though distortion is quite low, the distortion spectrum has a lot of high order harmonics that are slowly decaying. This might be a problem in the VAS or the driver circuit of the output pair? Please see measurement at 1kHz/100W/4om.
- distortion rises with frequency quite too much to my taste. Please see measurement of THD vs. frequency at 10W/4ohm.
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Yes, IIRC Mr. (Dr.?) Small claimed that he gave this idea to Phillips around day one. When I pointed out that the 5534 has a high output impedance at RF and the cap stops working he would have none of it. I presented my alternative (even Thorsten L. liked it). I ended up mentioning that I had no problem with folks that prefer SET's and horns and all hell broke loose (not quite)
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John, I thought you said they cut the bias back to have less quiescent power dissipation.
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