John Curl's Blowtorch preamplifier part III

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ahahaha what a crazy thinking. yes it can and does. Some day I will show you how those two instruments are used together. i have shown this setup on the equipment forum long ago. You are wasting everyones time.

No you cannot. There is no commercial ADC in the audio frequencies range on this planet that would provide -160dB THD+N, with or without a passive notch filter (that only helps with the dynamic range, not the distortion performance) and tricks like increasing the noise gain in the amplifier can only help so much. LIGO is using some -180dB in filtering the amplitude control of the laser. Talking about sources, Victor's fine oscillator is estimated between -140dB and -150dB distortions so no cigar for -160dB.

BTW, I have two of those Panasonic/Levear 7722A's and a Shibasoku AD725D + AG15C and the Shibasoku 2nd harmonic is not much better than -120dB. So unless you can come up with some solid data beyond "show me yours" photos, when it comes to measuring -160dB THD+N, I have to conclude you have no idea what you are talking about.

Meantime, you could consider an introductory lecture in ADC distortions definitions and types, and in particular about the effect of the ratio of sampling clock to the input frequency on the SFDR. Or ask about one of your 4 EEs working for you, I hope they have to knowledge and the guts to tell you the truth up front.
 
How am I supposed to know which way non-humans perceive anything? 🙂

Otoh the term "multidimensional" is also used when for example tasting something complex or comparing two tastes that differ in more than one perceptable dimension (means in different parameters).

Well, you mentioned music and humans, thought you may know something we don't 😉 I'm presuming you are referring to the kind or psychoacoustics that goes beyond what we all share?
 
Was it witty, or was he trying to be clever and condescending
I never found Jakob2 to be condescending.
I feel his answer to be in a very French humor: "Mot d'esprit". Sarcastic in appearance, but accomplice in the background, leading to reflection. I mean if we know a little what frequencies some animals can hear or see, how to know what they "feel" or think ?
I ask myself every day this question about my cat who managed to make me his willing slave.
He just protested rather dryly over the choice of his croquettes without more explanations: I changed his bowl.
 
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Have-you noticed that our audition is always correlated with our vision ? Listening to music on our hifi system, we imagine the concert hall and the musicians inside. We often use the word "Image " to figure out some of the aspect of our listening experiences.
Multidimensional.

No, never, and I doubt im the only one. So speak for your self. You constantly say these things like there universal truths, there not.
 
distortion magnifier and notch filter techniques easily do -180dB as Samuel Groner has shown. They keep wasting their time.

That's for opamps, not for audio power amplifiers... Distortion magnifier (e.g. use noise gain) makes sense at 140dB open loop gain. A conditionally stable audio power amplifier has all the chances in the world to start singing.
 
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No, never, and I doubt im the only one.
Don't you listen in stereo ?
It should be interesting to make a large-scale sample survey about this.
What i can say for sure is that is the first work of a sound engineer involved in mixing. Create a believable virtual listening room, and distribute the musician in this space.
If you are not sensible to this, may-I say you are loosing a part of this work ?
So speak for your self. You constantly say these things like there universal truths, there not.
Please, oh please consider that "truth" is not a word in my way to think, I'm not a believer.
I'm sorry if you have this feeling, despite all the (boring) care i take to add "omho", "i think", "in my book", "as i see the things" as often as possible.
It seems so obvious to me that, talking about human perceptions, all we can say is highly subjective by essence.
I have often explained that, if my way of expressing myself is a bit dry or rigid, you must understand that english is not the language of everyone here. A little indulgence?
By the way, a remark, isn't your answer also a little affirmative and definitive about your feelings about my little person ?

Friendly.
 
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Originally Posted by Tournesol View Post
Unless you record the instruments with proximity microphones, reproduce each with a separate speaker located in the same room and in the same localisation, with directivity curves identical to those of each instrument, we can never reproduce reality.
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Proximity mics wont work. Most instruments put out sound in all directions with different freq. rsponse for differnt directions. Sitting in front of a quartet with a french horn pointed backwards, most of the horn sound is bouncing off the back wall, hows a close mic going to recreate that.

The closest thing to being there is a dummy head recording ( you can make the ears copies of your own) over headphones. Guess what, people dont like the real thing, and most will tell you its not the same as being there untill you A/B the recording with the live show. Then they notice all the ( sometimes bad) reverb and echo, noise, and poor mix ( the trumpets too loud because its pointing right at me.) There are some exception like sitting close to a string quartet in a "chamber" but those are probably rare for most of us.
 
Guess what, people dont like the real thing, and most will tell you its not the same as being there untill you A/B the recording with the live show.
Ah, here I am forgiven. I’m not the only one who says things in a definitive way .
I would not comment* on the rest of your post on which we are in almost total disagreement.
Or agreement, if you re-read more carefully what I said.

* because it will not advance the subject of a millimeter.
 
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