John Curl's Blowtorch preamplifier part II

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A couple years ago Dark Side of the Moon was released on SACD and it sold 800,000 copies. CD sales have gone down but SACD has gone up. Check wiki SACD. 120 db dynamic range, 50Khz bandwidth etc. Multichannel capable. I guess it isnt dead after all -- still alive for jazz and classical music fans who appreciate quality sound. Support it or forever have MP3 quality everywhere.

And thank the great cosmic muffen for High Definition master digital downloads !

SACD is pretty dead, imo.

What is hot is the 24/192 download... looks like the future.
maybe it is just the present reality.

What I would like to see is this or a better format encoded onto a physical medium, like a CD or DVD disc. I am old school in that regard and have a mental fart at the thought of having a pile of "stuff" crammed into some hard drive or similar sort of thing bothers me on some level... dunno.

problem for me is that almost - not quite - everyone that I really want to hear in "high def" is boots up. :(

_-_-bear
 
Back 40 years ago, I worked with Bascom King and others with a company called 'Soundstorm'. With this system, you would have felt right at home, IF you can reference outside your own work. Lots of small cones, tubes and solid state, it did modest concerts in Santa Barbara, and I came along to help once or twice. One concert was with Doc. Watson (the blind folk guitarist). After the concert, Doc. Watson went out of his way to tell us that he appreciated the sound quality of the PA. Now that's FEEDBACK! However, when the Grateful Dead rented Soundstorm's system as an adjunct to the 'Wall of Sound', putting it on a delay line, and in the middle of the audience of an open air football stadium, I was told later that the system did not have enough 'juice' to do the job properly. Yet, for a folk group like: 'Old and in the Way' it was OK.

It is very good example John! :)

Like, you tried to use very nice system in the field that was not meant to it, the same way your Carlec Ambisonics will be used. People will try to use them where they use SM-80 and say how bad they are. Then they will complain that your microphones have to be wireless to be used. Then they will say that they are more expensive than Chinese copies of ancient German mikes, and so on. It is not enough to manufacture some revolutionary microphones to improve quality of records. You have to replace everything around that recording process, including skills of many audio engineers. And even artists!

Here is one more example: I tested a prototype of high-end PA on a bard-festival. It was the best place theoretically to test it: performers got used to play guitars and sing in front of people without any microphones, so it was normal for them to stay 3 feet from large diaphragm mikes, when listeners enjoyed top quality of sound. Everything was fine, until some famous bards come. They started complaining that they don't hear themselves. What does that mean? They got used to close miking, when they lick dynamic microphones and hear own distorted voices from floor monitors. Why it ever happened? Because such close miking become standard when drums were playing behind the singer. It was the necessity. But people got used to it, so it is hard to convince those who got used to what is alien to their genre, that it is alien to their genre!

Now, back to the initial question... If you are ready to start the revolution in recording you have to realize what you are facing...
 
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3 years ago I experimented with stereo microphone made of 5 Panasonic capsules, with corresponding matrix. It worked quite well, especially in headphones, you can hear what goes on around your head. No need for additional decoding, and full compatibility with existing equipment.

In marketing, timing is King. And ---- are headphones/earphones more popular now than ever before?! All the more reason that now is the time. We can do LTE to various mags -- like Broadcast Engineering and other recording mags as interested in better recordings and the soundfield mic technique in recording and musician mags --- LTE are read and they do respond to reader requests for articles.
 
In marketing, timing is King. And ---- are headphones/earphones more popular now than ever before?! All the more reason that now is the time. We can do LTE to various mags -- like Broadcast Engineering and other recording mags as interested in better recordings and the soundfield mic technique in recording and musician mags --- LTE are read and they do respond to reader requests for articles.

Theoretically I can quit the job. But I would need some income instead. And partners must understand that if I can't write the report what line on schematic I drew today, or which formula I calculated, that means I am stuck between multiple possibilities and can't get the decision right now, because it is not ready. But when ready it will be much better than if I took wrong direction, wasted time and material, but had good reports of work in process. :)

Wait, Edit: one more thing... Killing thing for Marketing... I can't predict how much time I need to complete the prototype.
 
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This is a test that would be fine for a first course in EE after a dozen lectures.

Now for those who have seen it before (Pavel, George, etc.) please wait a day before giving the answers.

The challenge is available to the rest.
 

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And others would simulate it, but there really are some neat issues here that would be missed by either of those approaches!

What neat issues? No neat issues. If you have current source with infinitely large output resistance you draw an equation for the current as the sum of 2 currents that always is equal to the supplied current. The rest is trivial.
 
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I have a Calrec schematic from the internet, this morning. Perhaps yours is different.
In any case, THINK what you could do to streamline and improve the ORIGINAL schematic. NO coupling caps everywhere, quad sims, quality surface mount, etc. Maybe a servo at the end, just to keep to accumulated DC offset to virtually zero.
Think of the quality bird call recordings you could make. You could just set up in the wilderness and go to lunch. Later, you could FIND and home in on the birds that are worth listening to!
and you would be transported to the exact spot where it was recorded. very nice realism.
 
Here is very good explanation of various surround microphone techniques

A Ambisonic-like mic- available for affordble price and great specs would sell now... in Guitar Center and all sorts of places. And, with mass marketing it would get popular. Then get magazine reviews and someone famous to endorse it. yadda yadda yadda. Just market the heck out of it.

Richard, who will design 4-ch per line consoles, effects, algorithms, etc for Ambisonic?
 
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