That's okay it really is just evening things out as one of the magazines I wrote for gave me a byline on an article I did not write!
Not bad delivery time to Oz.
I just this morning received Vol1 and noticed, as others have, the general improvements in publishing quality of this Bookzine over the first issue.
I haven't looked carefully at content yet, but it is great to see such in-depth treatments of audio topics and solid state designs in a periodical again.
Thanks for all the efforts, Jan and the authors. I think this is on the money!
I just this morning received Vol1 and noticed, as others have, the general improvements in publishing quality of this Bookzine over the first issue.
I haven't looked carefully at content yet, but it is great to see such in-depth treatments of audio topics and solid state designs in a periodical again.
Thanks for all the efforts, Jan and the authors. I think this is on the money!
Not bad delivery time to Oz.
I just this morning received Vol1 and noticed, as others have, the general improvements in publishing quality of this Bookzine over the first issue.
I haven't looked carefully at content yet, but it is great to see such in-depth treatments of audio topics and solid state designs in a periodical again.
Thanks for all the efforts, Jan and the authors. I think this is on the money!
Thanks Ian, I try my best. Must learn this trade!
BTW Your copy was shipped 26 March, so about 10 days to Oz seems indeed not bad. Thanks to the efficient German Postal Service.
I'm sure you'll like the contents, some great articles there!
(BTW All article abstracts can be read here).
jan
I'll take that as a "No!"
Figure 9 is an oscillator! The output stage inverts!
Anybody having problems with the presentation of the formulas on page 7?
For anyone worried about my pointing out the error(s), you should see the highlighter marks in most of my reference material. This issue has much fewer errors than any other publication I have looked at critically.
Jan,
I might do a very short article for the next volume on how global feedback effects the time it takes a signal to pass through an amplifier chain. If you are interested.
ES
That would require a lot of field research and after my comments on financing Jan would not pay for it. But I suspect the real problem is meaning. In some US slang a G-Pole is the pole used by "Exotic Dancers."
That would require a lot of field research and after my comments on financing Jan would not pay for it. But I suspect the real problem is meaning. In some US slang a G-Pole is the pole used by "Exotic Dancers."
Yeah, G-string, G-spot; I definitely wouldn't pay for that. I usually get it for free
jan
Yes indeed. Another entry for the futuire 'Oops!' menu.
Sounds intriguing, and would set straight a lot of anecdotal stories about the issue.
jan
I gave a lecture on the G-Pole priciple at ETF2010. It is an open baffle design with a twist.
It means Gerhard - Pol(e) because i wanted to diferentiate it from a mono-pol(e), di-pol(e),
bi-pol(e) and such. From the front it works like a conventional open baffle, from the back i use delay of the frequencies over ca. 1.5kHz to give the ouput combfiltering. That way the G-pole does not image from the back. A conventinal dipole does a phantom image when you stand in the back eg. producing another soundstage. Just walk through a dipole and listen. When you stand behind and turn around you can hear another stereo presentation. Standing behind a G-Pole you hear only difuse sound. The frequency response of that difuse sound is shaped in such a way so that the difuse sound has the same subjective tonal balance then the direct sound. You can find the curve for difuse incidence in the work of Zwicker. A sound that comes from the side is differently perceaved then a sound that comes from the front. The surprising outcome of my work makes placement of the open baffles much less critical as regards to the room boundaries. The setup of the G-poles at ETF needed only some minutes and was not tweeked in any way later. They where just sitting there where we put it and the sound in the rather big room was very musical right away.
It means Gerhard - Pol(e) because i wanted to diferentiate it from a mono-pol(e), di-pol(e),
bi-pol(e) and such. From the front it works like a conventional open baffle, from the back i use delay of the frequencies over ca. 1.5kHz to give the ouput combfiltering. That way the G-pole does not image from the back. A conventinal dipole does a phantom image when you stand in the back eg. producing another soundstage. Just walk through a dipole and listen. When you stand behind and turn around you can hear another stereo presentation. Standing behind a G-Pole you hear only difuse sound. The frequency response of that difuse sound is shaped in such a way so that the difuse sound has the same subjective tonal balance then the direct sound. You can find the curve for difuse incidence in the work of Zwicker. A sound that comes from the side is differently perceaved then a sound that comes from the front. The surprising outcome of my work makes placement of the open baffles much less critical as regards to the room boundaries. The setup of the G-poles at ETF needed only some minutes and was not tweeked in any way later. They where just sitting there where we put it and the sound in the rather big room was very musical right away.
Thanks Joachim,
Having attended your lecture at EFT2010 (although not totally sober; but neither were you
) it's good to have a review here.I'm sure you are aware of Siegfried Linkwitz Orion dipole, where he uses a rear-firing tweeter to make the whole speaker dipole from bottom to top octaves. He deliberately makes the rear wave have the same polar response as the forward wave (or as best he can). You deliberately make the rear wave diffuse. Does that mean that you can place a G-pole much closer to the rear wall, and what would that do to the room reflections? They will also be diffuse.
jan
Yes, the G-Pole can be put closer to the backwall and i did that at ETF. Where it does not help much is cancelation in the deeper regions. There can be a distance where the backwave is out of phase when it comes back to the front but being able to put the G-poles closer to the backwall i can shift that effect up in frequency where it is not that pronounced. A conventional dipole will not image well when too close to the backwall out of the mentioned reason that there is a second phantom or shaddow image. There is another speaker from John Kreskovsky, the Nao-Note that has a nearly perfect dipole character up to high frequencies. That and the Orion suffer from the same backwall problem though. In a big room with dipoles far from room boundaries this is fine but still the difuse sound from the back of those spaekers does not have the correct difuse field equalization. Provided that the room is not much damped the sound from the back has a freefield FRD with some loss in the treble and sounds tonally different then the sound from the front. Think about it. It´s not that easy as it seems. By the way, i was sober at that morning but holding a
seminar with a new content ( even for me ) at 9.00 in the morning is usualy the time when i am in a REM phase. It was taxing but i was really surprised that 80% of the population was there. That made me really happy. Those people are dedicated. I wish we had customers like that.
seminar with a new content ( even for me ) at 9.00 in the morning is usualy the time when i am in a REM phase. It was taxing but i was really surprised that 80% of the population was there. That made me really happy. Those people are dedicated. I wish we had customers like that.
Jan,
Lets talk about scary math. Most of what I see is usually just algebra, which we usually call arithmetic to indicate it is much easier than "real math."
It would just be arithmetic if values were given for all the numbers instead of symbols (X, Y, etc.) The way to keep useful knowledge from leaking out and frustrating newbies is of course to use a more complicated code such as Ic, Vbe, or Dss. That way when a newbie is confronted with a simple equation they really won't know what it means because they still have to learn the jargon.
That is why those folks who want to reveal the special secrets will make sure every term in an equation is defined in the article that uses it.
The second great way to conceal information is the use of "Identities." I know the Sin squared of X plus the Cos squared of x always equals 1. But for example when you simplify an equation by using such an "Identity" it is common practice not to mention this to again keep the newbies off balance. Of course in texts if they didn't just introduce the concept they would either show that step or mention it in a side bar.
So keep up the good work.
ES
Lets talk about scary math. Most of what I see is usually just algebra, which we usually call arithmetic to indicate it is much easier than "real math."
It would just be arithmetic if values were given for all the numbers instead of symbols (X, Y, etc.) The way to keep useful knowledge from leaking out and frustrating newbies is of course to use a more complicated code such as Ic, Vbe, or Dss. That way when a newbie is confronted with a simple equation they really won't know what it means because they still have to learn the jargon.
That is why those folks who want to reveal the special secrets will make sure every term in an equation is defined in the article that uses it.
The second great way to conceal information is the use of "Identities." I know the Sin squared of X plus the Cos squared of x always equals 1. But for example when you simplify an equation by using such an "Identity" it is common practice not to mention this to again keep the newbies off balance. Of course in texts if they didn't just introduce the concept they would either show that step or mention it in a side bar.
So keep up the good work.
ES
I'm not sure I agree there. If you wasnt to show the relation between, say, Vbe and Ic in an equation, you really should use Vbe and Ic. Using anything else and a 'translation list' is counter productive.
Yes, and Scott's article about low noise mic preamp design is a great example in case.
jan
I have no problems with using Vbe or Ic if you mention what they mean! It is when you say use Vdd without any other reference to it I think you have managed to reduce communication efficiency. Pg 7!
You know, these guys have no trouble grabbing the handles of the terms, any jargon in fact , and throwing them round the forums. I left a thread yesterday where a guy was showing a sim as having errors but he was just "pouring a plane" for earth to correct it. Hmm. I'm not so sure even the Math terms frustrate so much as make missiles to throw back.
Anyway, this sounds like a really good line of repellant you got here! Do you think it would work better on thread trolls even?
If you say so, I'll take a six-pack!
I think it's a fine line. On one extreme, you probably don't need to have explained that 'ohms' is a measure of resistance. Vdd? For me it's in the same class as 'Idd' or 'Vcc'.
But I got your point, I'll look out for it next time and try to avoid uncertainties here. Thanks for the heads-up.
jan didden