Of course, the wires you use in your amps for power, rails and speakers lines are <1mm² ?
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You are right Patrick. I use an open loop fet follower to buffer the DC voltages from the outside world, because this circuit has poor common mode rejection. Not a big problem, so long as you use clean power supplies.
The multitrack files are on Michael's HD, I will get a copy in the next couple of days.
Michael is back to Germany this weekend, and once there will do the mixdown and mastering.....final mastering will probably not be required.
We ran the system from a generator out in the carpark, and I used my Kikusui lab power supply/regenerator to power the desk, outboard, interface, laptop etc.....I came up with the album name 'Off Grid'.
The performance/PA sounded stunningly clean, clear and good, smiles all round from the small audience....ten from Perth and ten or so locals.
After the show we ran a rough mix back into the PA and took a listen.....jaw droppingly good.
We will have to wait for the final product, but the indications are that this indeed is a landmark recording, unusually if not uniquely clean clear and live with dynamics, groove and presence from heaven.
I am not sure how long the finalising will take, probably a couple of weeks....I can't wait to hear how it translates.
Dan.
Essentially a common-gate connection of the circuit you linked earlier? Looks a bit like Patrick's CEN, then. 🙂 Glad you're having fun.
With everything quiet, I might be able to elaborate on what many linear designers think is an important step in improving D-A performance.
Most of us who design serious audio equipment have found that the DIGITAL portion of the design appears to be very sophisticated, and highly developed. However, converting the output of these chips, with all the attendant 'trash' that is passed with the audio portion of the signal is a real challenge for conventional IC electronics. In fact, it might be 'impossible' with today's IC's to do a 'perfect' job, or what real experts can detect.
Many amateurs, and some interesting tube designs have already tried to make a 'perfect' output gain stage, and some might be very good. I decided to try for an 'ultimate' discrete, all fet gain stage, based on the Blowtorch line amp electronics, since it is the best that I know what to do, I have the fets, and it has been proven to work as a line stage and has, by design, a really high open loop bandwidth, class A in operation and at most, minimum open loop gain.
This gain stage differs from any designs that I normally design for Parasound, for example, because of the difficulty in matching and current biasing of this sort of design, but then I am trying to make a 'Ferrari' not a 'Ford' and the extra care might be worth it, as it has been proven to be with the Vendetta Research phono stage, CTC Blowtorch line stage, and other extremely hi end products.
Most of us who design serious audio equipment have found that the DIGITAL portion of the design appears to be very sophisticated, and highly developed. However, converting the output of these chips, with all the attendant 'trash' that is passed with the audio portion of the signal is a real challenge for conventional IC electronics. In fact, it might be 'impossible' with today's IC's to do a 'perfect' job, or what real experts can detect.
Many amateurs, and some interesting tube designs have already tried to make a 'perfect' output gain stage, and some might be very good. I decided to try for an 'ultimate' discrete, all fet gain stage, based on the Blowtorch line amp electronics, since it is the best that I know what to do, I have the fets, and it has been proven to work as a line stage and has, by design, a really high open loop bandwidth, class A in operation and at most, minimum open loop gain.
This gain stage differs from any designs that I normally design for Parasound, for example, because of the difficulty in matching and current biasing of this sort of design, but then I am trying to make a 'Ferrari' not a 'Ford' and the extra care might be worth it, as it has been proven to be with the Vendetta Research phono stage, CTC Blowtorch line stage, and other extremely hi end products.
I might add that we don't don't really know exactly what is 'wrong' with the conventional circuits, except that they do not sound 'right'. Most advanced audio linear designers think that it is something that our measuring equipment cannot actually measure, due to the fact that our measuring equipment itself is made of the very same IC's that we are trying to test. Almost 50 years ago, the late Richard Heyser first made this claim, even before the test equipment was made with IC's like they are today. I agree with him on this. I'm pretty sure that in future, we will have a better measurement method, just like we once had to make a better measurement for TIM distortion more than 40 years ago.
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Let me give an example of a passive part that 'measures' OK with conventional test equipment. In fact it is often added at the INPUT of much of the test equipment available today that makes all the very low THD and IM measurements, and that is a MYLAR capacitor. It can be shown that a Teflon or Polystyrene input cap would have significantly lower dielectric absorption or DA, but the test equipment, mainly single or multiple sine waves, just doesn't notice DA, yet the ear apparently can. Practical engineers often go for the 'spec' so they go for the relatively cheap and space effective Mylar, because it isn't noticed with these test signals.
....yet the ear apparently can...
Can you post one and only proof( DBT result)?? Or only claims.. 🙄
Can you post one and only proof( DBT result)?? Or only claims.. 🙄
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Who gives a ****. Don't you know any other drums to beat on? If you think JC continuing claims is brutal, well if you could only take the outside perspective and see how annoying pestering him about it and making an ordeal for pages and pages is... it just isn't important. Discussions about things you do care about will continue once you stop trying to make this hella old dog change.
Have you looked at Abraxalito's work on filters for DAC's? You might want to dig into that. I'll be really frank and say that I think most filters are designed poorly and sound poorly despite their supposed quality in measuring. The horrid sound of the OPPO should be enough evidence that there is more going on.
I fail to see how the only possibility is some sort of golden ratio of bandwidth and gain loop is going to be the answer to everyone's prayers.
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Talk was about coupling caps (no AC across capacitor in audio band, simple use big enough value), not applications in. filters.
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I quoted JC and spoke to him about filters, I wasn't referencing you about filters. With you I purely mean to give the whole DBT thing with JC a rest. It just stops more interesting discussion, flat. If you don't like his cap choice, don't use it... He's on a roll, and we've got things to talk about. Losing our nuts over parts selection is for down the road when we have a reason to pick them. In all fairness, I don't really know why JC brought it up now. Maybe he's trolling you, but why take the bait?
I'm not worried about DBT. Claims over several decades now continue to come in from the four corners of the earth. Many things are accepted as It Works, so use it.
The ancient Egyptians 2400 years ago used willow bark as a remedy for aches and pains. Centuries later, in the 1850's did they know it was salicylic acid. And after that how it (aspirin) worked. JC says, it works, so I use it. same - same.
But, they still cant measure pain directly. They have to ask the person for thier opinion.
I can just see the look on the patients face when the doctor tells him/her that his blood tests show no problem and therefore you have no pain or head ache.
THx-RNMarsh
The ancient Egyptians 2400 years ago used willow bark as a remedy for aches and pains. Centuries later, in the 1850's did they know it was salicylic acid. And after that how it (aspirin) worked. JC says, it works, so I use it. same - same.
But, they still cant measure pain directly. They have to ask the person for thier opinion.
I can just see the look on the patients face when the doctor tells him/her that his blood tests show no problem and therefore you have no pain or head ache.
THx-RNMarsh
That reminds me........ I need about 20W average to reach 90db spl at my listening position. How much power in Watts is 0.1%.
[ 8 Ohms]
THx-RNMarsh
[ 8 Ohms]
THx-RNMarsh
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Sword slices both ways, so you can cut the righteous act. This outsider says it was troll bait. For what I've been able to tell, Benchmark's 9038-based DAC is an 49720-based IV, which might as well be John's antithesis. Certainly no one is calling that system anything but "high end" both in cost and perception.
I'm going to keep cheering for NP/EUVL (among many) who do things in their characteristic way because they like doing it in that fashion and acknowledge that it's their philosophy, but there's other ways to skin a cat.
Otherwise is just a bunch of hot air blown around.
John why do you switch subjects all the time? I was looking forward to a discussion you started about a new I/V converter topology, and now all of a sudden its DACs.
You are always stating that you hope 'to have a useful discussion on audio design' but then when it takes off you change subject. This way there's nothing useful ever coming out of anything.
Jan
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